ANESTHESIA BOARD QUESTIONS 2015-2018
What is the onset of analgesia ollowing administration of epidural morphine 5 mg? (A) 30-60 minutes (B) 15-30 minutes (C) 5-15 minutes (D) >60 minutes Rationale: T e onset o epidural
(A) 30-60 minutes The onset o epidural morphine is 30 to 60 minutes. The duration of analgesia is 12 to 24 hours. Larger doses of epidural morphine are needed or analgesia. However, delayed respiratory depression may result.
What is the average weight of a 6-year-old? (A) 15 kg (B) 18 kg (C) 21 kg (D) 24 kg
(C) 21 kg A simple estimation of body weight by age is: 9 + (Age × 2).
What variables are needed to calculate systemic vascular resistance (SVR)? (A) Body surface area, cardiac output, and central venous pressure (B) Mean arterial pressure, heart rate, and pulmonary capillary wedge pressure (C) Mean arterial pressure, cardiac output, and pulmonary capillary wedge pressure (D) Mean arterial pressure, cardiac output, and central venous pressure.
(D) Mean arterial pressure, cardiac output, and central venous pressure. SVR = 80 x [MAP-CVP]/CO.
Which of the following opioids is unique in that it has both local anesthetic and narcotic properties? A. Morphine B. Nalbuphine C. Hydrocodone D. Meperidine E. Oxymorphone
(D) Meperidine in addition to its narcotic effects also demonstrates local anesthetic actions.
Which of the following agents will have the least effect on somatosensory-evoked potentials (SSEPs)? A. Vecuronium B. Propofol C. Fentanyl D. Nitrous oxide
A. Inhalational volatile anesthetics produce an increase in latency and decrease in amplitude of evoked potentials. Nitrous oxide produces a decrease in amplitude with no change in latency. Propofol decreases amplitude and an increase in latency of SSEPs. Muscle relaxants have no effect on SSEPs. Narcotics cause dose-dependent decrease in amplitude and increase in latency.
Regarding ventilation/perfusion mismatch (Select 2) A- HPV minimizes dead space B- Bronchioles constrict to minimize zone 1 C- Blood passing through under ventilated alveoli tends to retain pCÓ. D- The A-a gradient is small.
B- Bronchioles constrict to minimize zone 1 C- Blood passing through under ventilated alveoli tends to retain pCÓ.
According to the Modified Glasgow Coma Scale, a moderate head injury is associated with a score of: A-13 - 15 B-9 - 12 C-6 - 9 D-less than 6
B-9 - 12 According to the Modified Glasgow Coma scale, mild head injury is associated with a score of 13 - 15, moderate head injury is associated with a score of 9 - 12, and severe head injury is associated with a score of less than 8.
A woman with long-standing alcoholic cirrhosis (Child-Turcotte-Pugh B) presents to the emergency room for chronic shortness of breath and abdominal pain. A review of her lab findings reveal a hematocrit concentration of 36% (hemoglobin 12.4 g/dL) with an arterial blood gas revealing a PaÓ of 65 mm Hg breathing a FIÓ of 0.5 via face mask. Her vitals are a blood pressure of 135/60 mm Hg and a heart rate of 88 bpm. The most likely cause of her hypoxemia is' A. Intrahepatic arteriovenous shunts B. Intrapulmonary arteriovenous shunts C. Anemia D. Decreased cardiac output
B. Those with chronic liver disease are at increased risk of arterial-venous shunting. The presence of intrapulmonary shunting will result in hypoxemia.
When interpreting a CVP waveform, the beginning of systole is best represented by the A. A wave B. C wave C. V wave D. X decent
B. The A wave represents atrial contraction, the C wave represents bulging of the tricuspid valve into the atrium during the beginning of systole, the X decent occurs during systole and corresponds to atrial relaxation, the V wave represents filling of the atrium while the tricuspid valve is closed, and the Y descent occurs when the tricuspid valve opens and the atrium starts to empty.
Which of the following flowmeters is situated nearest to the gas outlet? A. Nitrous oxide B. Oxygen C. Air D. None of the above
B. The oxygen flowmeter is situated nearest to the gas outlet. This is because, if a leak develops in the flowmeter tubes, a hypoxic gas mixture can be delivered to the patient. To minimize this, the oxygen flowmeter is positioned downstream and nearest to the gas outlet.
When interpreting a CVP waveform, the end of systole best coincides with the A. A wave B. C wave C. V wave D. X decent
C. The A wave represents atrial contraction, the C wave represents bulging of the tricuspid valve into the atrium during the beginning of systole, the X decent occurs during systole and corresponds to atrial relaxation, the V wave represents filling of the atrium while the tricuspid valve is closed, and the Y descent occurs when the tricuspid valve opens and the atrium starts to empty.
Which cranial nerve (CN) provides sensation to the posterior 1/3 of the tongue? (A) CN I (B) CN V (C) CN IX (D) CN X
CN I (olfactory) provides innervation to the nasal mucosa; the superior and inferior surfaces o the hard and so t palate are innervated by fibers of CN V (trigeminal). CN IX (glossopharyngeal) innervates the posterior 1/3 of the tongue, whereas the lingual nerve provides sensation to the anterior 2/3 of the tongue. Areas of sensation below the epiglottis are innervated by CN X (vagus).
In patients receiving vecuronium, the greatest augmentation of neuromuscular blockade is seen with the use of: A-isoflurane B-sevoflurane C-desflurane D-nitrous oxide
C-desflurane Volatile agents decrease the nondepolarizer dosage requirements. The degree of the augmentation of blockade depends on the inhalational agent, with desflurane > sevoflurane > isoflurane > nitrous oxide.
Match each volatile agent with the number of fluorine atoms it contains. Isoflurane, 7 Desflurane, 5 Sevoflurante, 6
Isoflurane= 5 Desflurane= 6 Sevoflurane= 7
Side effects of intraspinal narcotics include:(Choose all the best answers). 1. Pruritus 2. Nausea and vomiting 3. Sedation 4. Urinary retention
(1,2,3,4) The most common side effect of intraspinal narcotics is pruritus (which appears unassociated with histamine release). Respiratory depression occasionally develops and is associated with a gradual progression of increasing sedation and decreasing respiratory rate. Nausea and vomiting, as well as urinary retention, are other untoward effects .
What is the maximal volume of solution that can be safely injected into the lumbar facet joint? (A) 1 mL (B) 2 mL (C) 3 mL (D) 4 mL
(A) 1 mL Intra-articular facet injection should be limited to 1-1.5 mL total volume to avoid damage to the capsule.
Which of these analgesic agents is a GABA agonist? (A) Baclofen (B) Pregabalin (C) Dexmedetomidine (D) Celecoxib
(A) Baclofen Baclofen is a GABA agonist
What are the benefits of the Bain circuit? (A) Decreases the circuit bulk and retains heat and humidity (B) Decreases resistance (C) Decreases fresh gas low (D) Scavenges waste gas
(A) Decreases the circuit bulk and retains heat and humidity. The Bain circuit incorporates the resh gas inlet tubing inside the breathing tube, which decreases the circuit bulk and retains heat and humidity.
Where does the spinal cord end in adults? (A) L1 (B) L2 (C) L3 (D) L4
(A) L1 : In adults the spinal cord ends at L1 and in some adults to L2. In children the cord ends at L3.
Which neuromuscular blocking drug is contraindicated during the care o a patient with Guillain-Barré syndrome? (A) Succinylcholine (B) Rocuronium (C) Atracurium (D) Pancuronium
(A) Succinylcholine THe risk oF severe hyperkalemia with succinylcholine is a contraindication
Following administration of spinal anesthesia the patient becomes hypotensive and bradycardic. What nerve fibers are affected? (A) T1- T4 (B) T5- T6 (C) T7- T8 (D) T10- T12
(A) T1- T4 Blocking the cardiac accelerator fibers results in bradycardia and hypotension.
What percentage of the total body water is extracellular (A) 67% (B) 33% (C) 25% (D) 100%
(B) 33% Extracellular uid (interstitial and intravascular) contains approximately 30% o the total body water. T e intracellular compartment is approximately 67% o the total body water
During an uncomplicated vaginal delivery, what is the expected blood loss? (A) 250 mL (B) 400 mL (C) 750 mL (D) 800 mL
(B) 400 mL The normal blood loss of vaginal delivery is 400-500 mL whereas the normal blood loss during cesarean section is 700-750 mL.
Where will you measure the blood pressure for patients undergoing surgery in the lateral decubitus position? (A) Nondependent arm (B) Both arms (C) Dependent arm (D) Right thigh
(B) Both arms Avoiding compression of the neurovascular bundle in the dependent arm is necessary. To determine perfusion to the extremity, monitor the blood pressure in the dependent arm intermittently. Checking a radial pulse is another sa ety measure.
What is your main anesthetic concern when caring for a patient taking anabolic steroids? (A) Myocardial in arction (B) Hepatotoxicity (C) Hypercoagulopathy (D) Stroke
(B) Hepatotoxicity Each of the responses may be linked to the use of anabolic steroids. Hepatotoxicity poses direct implications or the anesthetic plan speci cally regarding medications metabolized by the liver.
Which Mapleson circuit is most efficient or spontaneous ventilation? (A) Mapleson D (B) Mapleson A (C) Mapleson B (D) Mapleson C
(B) Mapleson A Because the fresh gas flow is equal to minute ventilation, the Mapleson A circuit is the most efficient or spontaneous ventilation.
Tachyphylaxis to local anesthetics is most closely related to which of the following? A. Speed of injection B. Dosing interval C. Temperature of local anesthetic D. Volume of local anesthetic E. pH of solution
(B) Tachyphylaxis is a well-known phenomenon associated with repetitive or continuous administration of local anesthetics. Several theories have been proposed to explain this tachyphylaxis, including increased uptake of drug from the epidural space, local edema, down-regulation of receptors, or spinal inhibition
The normal FEV1IFVC ratio is A. 0.95 B. 0.80 C. 0.60 D. 0.50 E. 0.40
(B) The forced expiratory volume in 1 second (FEV)) is the total volume of air that can be exhaled in the first second. Normal healthy adults can exhale approximately 75% to 80% of their forced vital capacity (PVC) in the first second. Therefore, the normal FEV)IFVC ratio is 0.80 or higher. In the presence of obstructive airway disease, the FEV)IFVC ratio is less than 0.80. This ratio can be used to determine the severity of obstructive airway disease and to monitor the efficacy of bronchodilator therapy
When the pressure gauge on a size "E" compressed-gas cylinder containing N20 begins to fall from its previous constant pressure of 750 psi, approximately how many liters of gas will remain in the cylinder? A. 200 B. 400 C. 600 D. 800 E. Cannot be calculated.
(B) The pressure gauge on a size "E" compressed-gas cylinder containing N20 shows 750 psi when it is full and will continue to register 750 psi until approximately three fourths of the gas has left the cylinder. A full cylinder of N20 contains 1590 L. Therefore, when 400 L of gas remain in the cylinder, the pressure within the cylinder will begin to fall.
Which estimation of blood volume per kilogram is correct or a 2-week-old? (A) 65 mL (B) 75 mL (C) 85 mL (D) 95 mL
(C) 85 mL Blood volume in the neonatal period is estimated to be between 80-90 mL/kg.
What do you anticipate during laparoscopic cholecystectomy? (A) Increased functional residual capacity (B) Increased closing capacity (C) Decreased functional residual capacity (D) Decreased peak inspiratory pressure
(C) Decreased functional residual capacity Due to insufflation with carbon dioxide, the functional residual capacity and closing capacity are decreased. The peak inspiratory pressure is increased
Which of the following occurs following administration of morphine? (A) Increased hypoxic drive (B) Decreased apneic threshold (C) Decreased hypoxic drive (D) Decreased PaCO
(C) Decreased hypoxic drive When administering narcotics, the hypoxic drive decreases as the PaCÓ increases along with the apneic threshold
The term luxury perfusion refers to a situation that occurs in the brain when A. Blood flow has resumed after a period of ischemia B. Blood flow is directed from a normal region of the brain to an ischemic region. C. Vasoparalysis exists D. The Robin Hood phenomenon exists E. A zone of ischemic penumbra exist.
(C) During acute focal cerebral ischemia, vasoparalysis results in impaired coupling between cerebral blood flow and metabolism. Consequently, cerebral blood flow is usually greater than cerebral metabolic rate and is passively associated with systemic arterial blood pressure. Under these circumstances, autoregulation and the reactivity of the cerebrovasculature to carbon dioxide is also disturbed. Thus, tight control of systemic arterial blood pressure is important in managing patients with focal ischemia, because cerebral perfusion is highly dependent on mean arterial blood pressure.
A 70-year-old patient with emphysema is undergoing an open cholecystectomy. What is the best anesthetic choice for this patient? (A) Spinal (B) Epidural (C) General (D) MAC
(C) General Regional anesthesia is used with caution for patients with pulmonary disease, specifically for surgical procedures above the umbilicus. The patient would benefit, however, from epidural analgesia.
What constitutes the eutectic mixture of local anesthetic? (A) Benzocaine and prilocaine (B) Prilocaine and tetracaine (C) Lidocaine and prilocaine (D) Prilocaine and nesicaine
(C) Lidocaine and prilocaine EMLA cream is 5% lidocaine and 5% prilocaine (1:1 mixture).
The highest trace concentration of N20 allowed in the OR atmosphere by the National Institute for Occupational Safety and Health (NIOSH) is A. 1 part per million (ppm) B. 5 ppm C. 25 ppm D. 50 ppm E. 100 ppm
(C) NIOSH sets guidelines and issues recommendations concerning the control of waste anesthetic gases. NIOSH mandates that the highest trace concentration of N20 contamination of the OR atmosphere should be less than 25 ppm.
Proper processing of platelet concentrates (to avoid future hemolytic transfusion reactions) before administration involves A. Type and cross match B. ABO and Rh matching C. Rh matching only D. ABO matching only E. Platelets can be administered without regard to any antigen system.
(C) Platelet concentrates contain a fair amount of plasma and white blood ceils (WBCs) but relatively few RBCs. Although ABO-compatible platelet transfusions are preferred (platelets survive better and crossmatching for subsequent RBCs is easier), in emergencies it has been noted that platelets often give adequate hemostatis without regard to ABO compatibility. Even though there are only small quantities of RBCs in platelets, the RBCs present can cause Rh immunization if Rh-positive platelet concentrates are injected into Rh-negative patients. Thus, until childbirth is no longer possible, Rh-negative females should only receive Rh-negative platelets.
When administering a spinal anesthetic, which nerve roots are easily blocked? (A) Smaller, unmyelinated (B) Larger, myelinated (C) Smaller, myelinated (D) Larger, unmyelinated
(C) Smaller, myelinated Smaller myelinated nerves are blocked easier than larger, unmyelinated nerve roots.
How would you classify a patient with repeated blood pressure measurements ranging from 160/100 to 179/109? (A) High normal (B) Stage 1 hypertension (C) Stage 2 hypertension (D) Stage 3 hypertension
(C) Stage 2 hypertension Rationale: Stage two or moderate hypertension is de ned as systolic pressure between 160 to 179 mmHg and diastolic pressure between 100 to 109 mmhg
Calculate the systemic vascular resistance (in dynes/sec/cm-5) from the following data: cardiac output 5.0 Umin, central venous pressure 8 mm Hg, mean arterial blood pressure 86 mm Hg, mean pulmonary arterial blood pressure 20 mm Hg, pulmonary capillary wedge pressure 9 mm Hg, heart rate 85 beats/min, patient weight 100 kg. A. 750 B. 1000 C. 1250 D. 1500 E. Cannot be calculated
(C) Systemic vascular resistance can be calculated using the following formula: SVR= MAP-CVP x80 CO where SVR is the systemic vascular resistance, MAP (mm Hg) is the mean arterial pressure, CVP (mm Hg) is the central venous pressure, CO (L/min) is the cardiac output, and 80 is a factor to convert Wood units to dynes-sec-cm-5• Calculation of SVR from the data in this question is as follows.
A size "E" compressed-gas cylinder completely filled with N20 contains how many liters? A. 1160 B. 1470 C. 1590 D. 1640 E. 1750
(C) The World Health Organization requires that compressed-gas cylinders containing N20 for medical use be painted blue. Size "E" compressed-gas cylinders completely filled with N20 contain approximately 1590 L of gas
How much blood loss is recommended for the use of cell salvage? (A) 250 mL (B) 500 mL (C) 750 mL (D) 1,000 mL
(D) 1,000 mL Cell salvage is used in large blood loss surgeries (1,000 mL or greater).
What is the blood-to-gas partition coeffcient of halothane? (A) 0.47 (B) 0.65 (C) 1.4 (D) 2.4
(D) 2.4
Which valvular disorder leads to the largest ventricular volume? (A) Mitral stenosis (B) Aortic stenosis (C) Mitral regurgitation (D) Aortic regurgitation
(D) Aortic regurgitation This question is an application of the left ventricular pressure-volume loops for patients with valvular heart disease. Aortic regurgitation causes volume overload of the left ventricle.
What sign is not an effect of hyperparathyroidism? (A) Hypertension (B) Ventricular arrhythmias (C) Muscle weakness (D) Hypochloremic metabolic acidosis
(D) Hypochloremic metabolic acidosis Hyperchloremic metabolic acidosis is a renal effect of hyperparathyroidism.
What is the hallmark laboratory finding associated with pyloric stenosis? (A) Hypokalemic hypochloremic metabolic acidosis (B) Hypokalemic hyperchloremic metabolic alkalosis (C) Hyperkalemic hypochloremic metabolic acidosis (D) Hypokalemic hypochloremic metabolic alkalosis
(D) Hypokalemic hypochloremic metabolic alkalosis Vomiting causes loss o stomach acid and electrolytes.
Which adrenergic agonist increases the heart rate the greatest? (A) Norepinephrine (B) Dobutamine (C) Ephedrine (D) Isoproterenol
(D) Isoproterenol Heart rate is affected least by phenylephrine and norepinephrine (decreased); and ephedrine (increased). Administering isoproterenol increases heart rate the greatest.
Baralyme granules are composed of :(Choose all that apply) 1. Calcium hydroxide 2. Sodium hydroxide 3. Water 4. Silica
1,3 Baralyme granules consist of 80% calcium hydroxide and 20% barium hydroxide, and contain water as the barium hydroxide octahydrate salt
CBF autoregulation is altered by::(Choose all of the questions that are correct). 1. Ischemia 2. Chronic hypertension 3. Halothane 4. N20
1. Ischemia 2. Chronic hypertension 3. Halothane
If a drug is usually 98% bound by plasma protein and the bound fraction is reduced to 96%, the free fraction will increase by:
100% % change= [(new value-old value)/old value] x100 =[(4-2)/2]x100 =2/2 x100 =1 x100 =100
Pulmonary hypertension is defined as a mean pulmonary artery pressure of at least : A- 25 mmhg B- 20 mmhg C- 15 mmhg D- 30 mmhg
A- 25 mmhg PTN is defined as a PAP of greather than 25.
Examples of Type IV hypersensitivity reactions include: A-contact dermatitis B-hemolytic transfusion reactions C-anaphylaxis D-angioedema
A-contact dermatitis Type IV hypersensitivity reactions are delayed and cell-mediated. Examples of Type IV reactions include contact dermatitis, tuberculin-type hypersensitivity and chronic hypersensitivity pneumonitis.
A maximal mid-expiratory flow rate (FEF25-75) of less than 70% is often the only abnormality seen in the early course of which disorders? (Choose 2 that apply) a. Cystic fibrosis b. Pulmonary edema c. Chronic Bronchitis d. Scarcoidosis
A;C Cystitic fibrosis, chronic bronchitis
In patients with chronic obstructive pulmonary disease (COPD)ipratopium acts by A . Competitive inhibition of cholinergic M3 receptors B. Noncompetitive inhibition of cholinergic M3 receptors C. Noncompetitive inhibition of cholinergic M2 receptors D. Competitive inhibition of B2 receptors E. Competitive inhibition of B1 receptors
ANSWER: A Ipratropium is a competitive inhibitor of cholinergic M3 receptors and is thus more eff ective at producing bronchodilation in patients with chronic bronchitis and emphysema than beta agonists, which are more effective in asthmatics.
Your patient tells you 10 minutes before his scheduled femoro-femoral bypass grafting that he has von Willebrand disease. He is unable to give you further information. The surgeon requests a general anesthetic. Your next action would be which of the following? A . Perform a history and physical, and if unremarkable, proceed to surgery. B. Postpone surgery and obtain a hematology consultation. C . Administer DDAVP and proceed with surgery. D. Administer platelets and von Willebrand factor and proceed with surgery. E. Check PT, PTT, and INR, and if normal, proceed with surgery.
ANSWER: B Von Willebrand disease (vWD) is the most common inherited bleeding disorder, with an estimated incidence of 1 in 100 to 1,000 people. Unlike hemophilia, it affects both males and females. There are three main types of vWD. Type 1 and 2 are inherited in an autosomal dominant fashion, while type 3 is autosomal recessive. An acquired vWD is seen in patients with auto-antibodies to von Willebrand factor (vWF) and certain patients with aortic stenosis. Most patients with vWD have the mildest and most common form, type 1, accounting for approximately 75% of all patients. A thorough history and physical, such as asking about bleeding after tooth extraction and other surgeries, nosebleeds, gingival oozing, hemarthrosis, petechiae, and bruises, can provide most of the risk stratification. An unremarkable history and physical would suggest a milder type of vWD, likely type 1. Patients with type 2 (defective vWF) and type 3 (generally absent vWF and low factor VIII levels) have more severe disease. Answers A and C suggest that the patient has vWD type 1. However, because management would be different based on the different subtypes, further information should be obtained regarding this patient's subtype before proceeding. Thus, further workup with a hematology consultation should be obtained to determine the subtype of vWD. Initial tests to evaluate for vWD may include vWF:RCo, vWF:Ag, and factor VIII activity. Administering vWF may help, especially if there is also factor VIII with it; however, this patient may not need this treatment. Platelet transfusions will not help in vWD. Similarly, the test of the intrinsic or extrinsic pathways will likely be normal.
Select the 3 indicators of increased dead space. A-LMA B- PPV C- Atropine D- Neck flexion E- Hypotension F- Endotracheal tube
B- PPV C- Atropine E- Hypotension
Anatomic dead space begins in the mouth and ends in the: A- Respiratory bronchioles B- Terminal bronchioles C- Alveolar duct D- Small airways
B- Terminal bronchioles
A 24-year-old female is scheduled for resection of a cerebral aneurysm. She has no other significant past medical history. Acceptable levels of hypotension would include a mean arterial pressure of: A-20 - 30 mm Hg B-35 - 45 mm Hg C-50 - 60 mm Hg D-90 - 100 mm Hg
C-50 - 60 mm Hg Healthy young individuals tolerate mean arterial pressures as low as 50 - 60 mm Hg without complications. Chronically hypertensive patients have altered autoregulation of cerebral blood flow and may tolerate a mean arterial pressure of no more than 20 - 30% below baseline.
The speed in an inhalation induction is slowed by right-to-left shunting. The change in the rate of induction is LEAST pronounced when using: A-nitrous oxide B-sevoflurane C-isoflurane D-desflurane
C-isoflurane With right-to-left shunting there is slowing of an inhalation induction. This effect is less pronounced with agents with high blood/gas solubilities.
During the administration of general anesthesia for a radical prostatectomy, the rhythm strip below is obtained. The most appropriate therapeutic measures at this time would include: A-initiation of a nitroglycerine infusion B-administration of metoprolol C-requesting the use of a bipolar cautery D-engage the artifact filter on the ECG monitor
C-requesting the use of a bipolar cautery This rhythm strip indicates a paced rhythm with clearly visible pacer spikes. Electrical interference from the electrocautery can be interpreted as myocardial activity and can suppress the pacemaker generator. The use of a bipolar cautery will reduce the electrical interference produced; if that is not possible, then pure cut is better than "blend" or "coag."
Extracorporeal shock wave lithotripsy therapy proceeds with the shock wave synchronized with what ECG phase of the cardiac cycle? A. The P wave B. The Q wave C. The R wave D. The S wave
C. Shock wave-induced cardiac arrhythmias occur in up to 10% to 14% of patients undergoing lithotripsy despite the fact that shock waves are purposefully synchronized with the patient's ECG and are delivered in the refractory period of the cardiac cycle (R wave)
The sural nerve supplies sensation for which part of the foot? A. Heel B. First 3 digits C. Lateral D. Medial
C. Lateral
Which of the following pulmonary function tests is least dependent on patient effort? A. FEV1 B. FVC C. FEFSOO-1200 D. FEF25%_75% E. MVV
D. FEF25%_75%
All of the following decrease cerebral blood flow (CBF), except: A. Etomidate B. Propofol C. Thiopental D. Ketamine
D. Propofol, barbiturates, and etomidate produce dose-dependent decreases in cerebral metabolic rate and CBF. Ketamine is the only induction agent that dilates the cerebral vasculature and thus increases CBF (50% to 60%).
Blood products are tested for all of the following, except A. Hepatitis C B. HIV C. West Nile virus D. Herpes virus
D. The incidence of infection from blood transfusions has markedly decreased. Although many factors account for the marked decreased incidence of transmission of infectious agents via blood transfusion, the most important one is improved methods for testing of donor blood. Currently, hepatitis C, HIV, and West Nile virus are tested by nucleic acid technology
Which of the following nerves must be separately blocked during an axillary approach to the brachial plexus? (A) Musculocutaneous (B) Ulnar (C) Medial brachial cutaneous (D) Median
During the axillary approach to the brachial plexus, the block is per formed in the axilla, where large terminal branches have formed. At this point the musculocutaneous nerve (MCN) lies deep within the coracobrachialis, having already left the sheath. A separate block is there ore essential to complete orearm and wrist anesthesia. T e MCN can be blocked by redirecting the needle, a ter completing the axillary block, superiorly and posterior to inject within the coracobrachialis.
Match each term with its definition a. endocrine function b. paracrine function c. autocrine function 1. hormone enters the blood & acts at distant site 2. hormone acts at site of origin 3. hormone acts adjacent to site of origin
Endocrine= distant site Paracrine= adjacent to site of origin Autocrine= site of origin
VEP> MEP> SSP> BSAEP
Name the order of resistance of electrophysological monitoring to anesthestics
An adult patient's platelet count is 25,000/µL. After trans using the patient with 2 units of apheresis platelets, what would you expect the platelet count to be? (A) 30,000-35,000/ µL (B) 55,000-85,000/ µL (C) 85,000-145,000/ µL (D) 145,000-165,000/µL
One unit of apheresis platelets will increase the platelet count by 30,000-60,000/µL. Two units of apheresis platelets will increase the platelet count by 60,000-120,000/µL. A single unit of platelets will increase the platelet count by 5,00010,000/µL.
Does "light" anesthesia promote wheezing?
Yes, if patint has a reactive airway.
Which drugs are noncompetitive antagonist? (select 2) a. phenoxybenzamine b. Nalbuphine c. Aspirin d. Atropine
a. phenoxybenzamine c. Aspirin
A patient has a right-to-left intracardiac shunt. The rate of rise of FA/FI of which of the following drugs will be least affected? a. Nitrous oxide b. Isoflurane c. Sevoflurane d. Desflurane
b. Isoflurane A R to L cardiac shunt slows the speed of induction with a volatile agent. Agents with high solubility (isoflurane) are affected least, while those with low solubility (desflurane) are affected the most.
5% EMLA cream consists of: (select 2) a. 5% benzocaine b. 5% procaine c. 2.5% prilocaine d. 2.5% lidocaine
c. 2.5% prilocaine d. 2.5% lidocaine
All of the following enhance renal perfusion except: a.PGE2 b. fenoldopam c. atrial natriuretic peptide d. thromboxane A2
d. thromboxane A2 it is a renal vasoconstrictor. its production is increased during renal ischemia
Match the pharmacodynamic effects of volatile anesthetics to the site of action: a. immobility b. amnesia c. analgesia d. unconsciousness 1. hippocampus 2. ventral horn 3. reticular activating system 4. spinothalamic tract
immobility= ventral horn amnesia= hippocampus analgesia= spinothalamic tract unconsciousness= reticular activating system
Patients with allergies to which food(s) have been reported to have latex cross-sensitivity? (Choose 3 that apply) a. bananas b. avocados c. kiwis d. eggs e. wheat products
a, b, c bananas, avocados, kiwis. Antibiotics that exhibit cross-sensitivity to latex have been demonstrated in people who also are allergic to bananas, kiwi, and or avocado.
Hypersensitivity Reactions: a- Type I 1. ABO incompatibility b- Type II 2. Contact Dermatitis c- Type III 3. Anaphylaxis d- Type IV 4. Serum sickness after snake bite
a,3 b, 1 c, 4 d, 2
Identify the drugs that undergo perfusion-dependent hepatic elimination (select 3) a. Lidocaine b. Diazepam c. Fentanyl d. Propofol e. Remifentanil f. Rocuronium
a. Lidocaine c. Fentanyl d. Propofol perfusion dependent hepatic elimination: fentanyl, lidocaine, propofol capacity dependent hepatic elimination: diazepam, rocuronium
MAC is reduced by: (select 2) a. N2O b. chronic alcohol consumption c. hyponatremia d. acute cocaine intoxication
a. N2O c. hyponatremia
All of the following contribute to hypertension in the obese patient except: a. decreased blood viscosity b. angiotensinogen c. hyperinsulinemia d. cytokines
a. decreased blood viscosity
The routine administration of succinylcholine is contraindicated in young children because of the possibility of: a. hyperkalemic rhabdomyolysis b. bradycardia c. trismus d. malignant hyperthermia
a. hyperkalemic rhabdomyolysis (in pts. with undiagnosed muscular dystrophy)
Hepatocytes produce: (select 3) a. thrombopoietin b. immunoglobulins c. alpha-1-acid glycoprotein d. factor III e. factor VII f. factor VIII
a. thrombopoietin c. alpha-1-acid glycoprotein e. factor VII VIII produced by sinusoids, III by vascular endothelium immunoglobulins by plasma
Identify the drugs that undergo metabolism by nonspecific esterases (select 3) a. succinylcholine b. remifentanil c. fospropofol d. tetracaine e. atracurium d. esmolol
b. remifentanil e. atracurium d. esmolol succ & tetracaine: pseudocholinesterase fospropofol: alkaline phosphatase
Common physiologic changes in the patient with cirrhosis include all of the following except: a. right to left shunt b. respiratory acidosis c. decreased glomerular filtration rate d. increased CO
b. respiratory acidosis pulmonary vasodilation, right to left shunt, hypoxemia; hyperventilate to offset reduced PaO2--resp alkalosis
Regarding the modern halogenated anesthetics in the adult at 1 MAC: a. minute ventilation increases b. respiratory rate increases c. dead space decreases d. airway diameter decreases
b. respiratory rate increases Vt decreases & RR increases leading to increased dead space ventilation airway diameter increased (bronchodilators- decreased resistance) MV is reduced
Volatile anesthetics produce unconsciousness by depressing the: a. spinothalamic tract b. reticular activating system c. pons d. hippocampus
b. reticular activating system
Which is the most important organ for metabolism of drugs? a - Lungs b- small intestine c- liver d- kidneys
c - liver [The liver is the primary site of production of the enzymes responsible for almost all drug metabolism].
Which level is designated by the interstial line ? a- C6 b- T4 c- T6 d- L4
d- L4 HORIZONTAL LINE FROM L3-L4
In which of the following circumstances is supplemental oxygen, less likely to increase arterial oxygenation? a- opioid overdose. b- copd c- pulmonary fibrosis d- pulmonary edema
d- pulmonary edema Pulmonary edema is an example of a right to left shunt. A right-to-left shunt that exceeds 50%, typically wont respond to increases in FiÓ.
What type of bond is formed when edrophonium binds o the anionic site on AChE? a. covalent b. ester c. hydrogen d. electrostatic
d. electrostatic AChE hydrolyzes Ache into choline & acetate; this enzyme can be inhibited at the anionic site &/or esteratic site--type of bond that is formed determines the drug's DOA. Edrophonium forms electrostatic bond at anionic site & hydrogen bond at esteratic site (weak bonds-short DOA) Neostigmine, pyridostigmine, physostigmine form a caramel ester at esteratic site (stronger bonds- longer DOA)
Match each local anesthetic with its maximum allowable dose in the adult a. ropivacaine ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,1. 200mg b. bupivacaine ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,2. 300mg c. lidocaine ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,3. 400mg d. mepivacaine ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,4. 175mg
ropivacaine= 200mg bupivacaine= 175mg lidocaine= 300mg mepivacaine= 400mg
The highest incidence of muscle pain following the use of succinylcholine is seen in: A-infants B-octogenarians C-outpatients D-pregnant patients
outpatients C-Myalgia following the use of succinylcholine is most commonly seen in females and outpatients. Pregnancy and extremes of age seem to be protective.
An increase in intraocular pressure has been associated with: (select 3) A-nitrous oxide administration B-succinylcholine administration C-opioid administration D-hyperventilation E-laryngoscopy F-hypoxemia G-sevoflurane administration
succinylcholine administration, hypoxemia, laryngoscopy Succinylcholine increases intraocular pressure by 5 - 10 mm Hg for 5 - 10 minutes after administration. This increase is primarily the result of prolonged contracture of the extraocular muscles from the depolarizing effects of succinylcholine. Nitrous oxide, volatile anesthetic agents and opioids have been associated with a reduction in intraocular pressure. Hypoxemia, hypercarbia, hypertension, hypervolemia, laryngoscopy and intubation have all been shown to increase IOP.
Match each type of pneumocyte with its role in the lung: type 1 type 2 type 3 provides surface for gas exchange promotes immunity produces surfactant
1= provides surface for gas exchange 2= produces surfactant 3= promotes immunity
A decrease in cerebral blood flow is seen after the administration of: A- isoflurane B- propofol C- desflurane D- ketamine
B-propofol The inhaled anesthetic agents and ketamine all increase cerebral blood flow (CBF). Benzodiazepines, etomidate, propofol and barbiturates all decrease CBF.
A patient with a DES presents for bunionectomy. What is the minimal amount of time that the patient should wait before she undergoes surgery? (answer in weeks)
52 weeks BMS- 30 days DES- 1 year
Match each disease to its underlying pathophysiology a. Addison's disease b. Conn's syndrome c. Cushing's syndrome 1. inadequate cortisol 2. excess aldosterone 3. excess cortisol
Addison's= inadequate cortisol Conn's= excess aldosterone Cushing's= excess cortisol
Which of the following local anesthetic concentrations is(are) isobaric? (Choose all that apply). 1. 2% Lidocaine 2. 0.5% Tetracaine 3. 0.5% Bupivacaine 4. 0.75% Bupivacaine
All of these local anesthetic concentrations are isobaric. Tetracaine 0.5% is prepared by mixing equal volumes of 1 % tetracaine and preservative-free saline. Hyperbaric solutions can be prepared by mixing equal volumes of 1% tetracaine and 10% dextrose, resulting in 0.5% tetracaine in 5% dextrose, or by mixing equal volumes of 0.75% bupivacaine with 10% dextrose, yielding a 0.375% solution of bupivacaine in 5% dextrose. Alternatively, factory-mixed preparations of 0.75% bupivacaine in 8.25% dextrose and 5% lidocaine in 7.5% dextrose are available. To prepare hypobaric tetracaine, 10 mg (1 mL of 1 % tetracaine) are mixed with 9 mL of sterile H20 to yield 10 mL of 0.1 % tetracaine. This has a baricity of 1.0
Which two lung pathologies are Forms of COPD? Select (2) two (A) Asthma (B) Chronic bronchitis (C) Aspiration pneumonitis (D) Emphysema
B) Chronic bronchitis D)Emphysema Rationale: Emphysema and chronic bronchitis provide the prototype o pathological changes in COPD.
Which initial intervention is correct i pulmonary embolism is suspected? (A) Discontinue intravenous Fluids (B) Increase FiO 2 (C) Extubate the patient (D) Discontinue inotropic support
B) Increase FiO 2 Rationale: Increase intravenous uids, keep the patient intubated, provide inotropic support, and increase FiÓ.
An increase in [HC03 -] of 10 mEq/L will result in an increase in pH of A. 0.10 pH units B. 0.15 pH units C. 0.20 pH units D. 0.25 pH units E. None of the above
B) There are several guidelines that can be used in the initial interpretation of ABGs that will permit rapid recognition of the type of acid-base disturbance. These guidelines are as follows: 1) a 1 mm Hg change in Pacó above or below 40 mm Hg results in a 0.008 unit change in the pH in the opposite direction; 2) the Pacó will decrease by about 1 mm Hg for every 1 mEqlL reduction in [HC03-] below 24 mEqlL; 3) a change in [HC03-] of 10 mEqlL from 24 mEqlL will result in a change in plf of approximately 0.15 pH units in the same direction.
When performing a transversus abdominis plane (TAP) block, the goal is to deposit/inject local anesthetic between which of the following two muscle layers? A. External oblique and internal oblique muscles B. Internal oblique and transversus abdominis muscles C. Transversus abdominis and external oblique muscles D. Rectus abdominis and external oblique muscles
B. The subcostal (T12), ilioinguinal (L1), and iliohypogastric (L1), and genitofemoral nerves are targeted when performing a TAP block. These nerves have a typical distribution between the internal oblique and transversus abdominis muscles.
What artery provides the majority to the blood supply to the anterior, lower 2/3 of the spinal cord? (A) Posterior spinal artery (B) Artery of Adamkiewicz (C) Posterior inferior cerebellar artery (D) Intercostal arteries
Blood flow to the posterior 1/3 of the spinal cord is provided by the posterior spinal artery. The posterior inferior cerebellar artery needs the posterior spinal arteries. The intercostal arteries provide blood flow to the anterior and posterior spinal arteries. The largest of the arteries supplying the spinal cord is the arteria radicularis magna (Artery of Adamkiewicz). Ref
The body mass index (BMI) associated with morbid obesity is: A > 30 B > 35 C > 40 D > 45
C > 40 Overweight and obesity are classified using the BMI. Overweight is defined as a BMI > 24, obesity as a BMI > 30, morbid obesity as a BMI > 40, super obesity as a BMI > 50 and super-super obesity as a BMI > 60. BMI is calculated with the following formula: BMI = Weight (kg) / Height (meters)2
High block with epidural or spinal anesthesia is characterize d by all of the following, except: A. Hypotension B. Bradycardia C. Tachypnea D. Respiratory insufficiency
C Tachypnea High spinal can affect the pons respiratory centers causing respiratory insufficiency or apnea while hypotension and bradycardia is from anesthesia reaching the brain stem and medullary hypoperfusion.
A 35-year-old Army captain who presents for a thoracotomy for right upper lobectomy secondary to tuberculosis has a mildly prolonged bleeding time on preoperative blood work drawn 1 week ago. Other lab results include white cell count 6, hematocrit 35, platelets 250K, and INR 1.0. Upon questioning, he denies spontaneous bleeding, easy bruising, excessive bleeding at the dentist, or a family history of bleeding disorders. His medications include atenolol, baby aspirin (stopped 1 week ago), and simvastatin. He does not take herbal supplements. Your physical examination is unremarkable. Th e surgeon and patient would both like an epidural for postoperative analgesia. Th e next appropriate step would be to: A. Repeat the bleeding time test. If the bleeding time is prolonged, skip the epidural. B. Not perform an epidural, as the bleeding risks outweigh the benefits. C. Perform the epidural, as bleeding times do not predict bleeding tendency and have uncertain value in the perioperative setting. D. Administer platelets, as the prolonged bleeding time implies abnormal hemostasis. E. Order a platelet aggregation test. If normal, place the epidural,
C The bleeding time is a test to assess platelet function. It is performed by making an actual cut on the forearm and observing the duration of bleeding until hemostasis occurs. A normal bleeding time generally ranges between 2 and 9 minutes. Th e most common causes of a prolonged bleeding time are aspirin, nonsteroidal anti-infl ammatories, or any other cyclooxygenase inhibitors. Other causes include von Willebrand disease, certain vascular diseases such as scurvy, thrombocytopenia, disseminated intravascular coagulation, and hypofi brinoginemia. Heparin and warfarin can also prolong the bleeding time while aff ecting the results of other coagulation tests. W hile a prolonged bleeding time in theory may indicate a vascular defect, platelet function defect, or thrombocytopenia, its role as a diagnostic and predictive test is questionable. A prolonged result is nonspecifi c and studies have not demonstrated a correlation between bleeding time, bleeding tendency, and blood loss. As such, the bleeding time by itself should not infl uence the decision to place an epidural S uspected bleeding problems can frequently be determined by the history and physical alone. Th e ASRA Consensus Conference states, "There is no wholly accepted test, including the bleeding time, which will guide antiplatelet therapy. Careful preoperative assessment of the patient to identify alterations of health that might contribute to bleeding is crucial. These conditions include a history of easy bruisability/excessive bleeding, female gender, and increased age." Given this patient's negative history and physical findings, along with aspirin ingestion, which could account for the prolonged bleeding time, it would be unlikely that he has a clinically significant bleeding disorder. Th us, repeating the bleeding time test is unnecessary, as is ordering a further workup with a platelet aggregation test. Th e platelet aggregation test involves drawing a specimen and using an aggrenometer to measure the turbidity of the plasma. It should be ordered in conjunction with a hematology consult if there is a clinical suspicion that there is a bleeding disorder. Placing a thoracic epidural for thoracotomy provides the benefits of improved analgesia in comparison to intravenous analgesia, and should be used when possible. Th ere is no clear indication for a platelet transfusion as the patient's platelet count is normal and there is no evidence of platelet dysfunction outside of aspirin use.
Select the FALSE statement concerning autonomic hyperreflexia. A. Distention of a hollow viscus below the level of the spinal cord transection can elicit autonomic hyperreflexia B. Up to 85% of patients with a spinal cord transection above the T6 dermatome will exhibit autonomic hyperreflexia under general anesthesia C. Propranolol is effective in treating hypertension associated with autonomic hyperreflexia D. Spinal anesthesia is effective in preventing autonomic hyperreflexia E. Cutaneous stimulation below the level of the spinal cord transection can elicit autonomic hyperreflexia.
C) Autonomic hyperreflexia is a neurologic disorder that occurs in association with resolution of spinal shock and a return of spinal cord reflexes. Cutaneous or visceral stimulation (such as distention of the urinary bladder or rectum) below the level of the spinal cord transection initiates afferent impulses that are transmitted to the spinal cord at this level, which subsequently elicits reflex sympathetic activity over the splanchnic nerves. Because modulation of this reflex sympathetic activity from higher centers in the central nervous system is lost (as a result of the spinal cord transection), the reflex sympathetic activity below the level of the injury results in intense generalized vasoconstriction and hypertension. Bradycardia occurs secondary to activation of baroreceptor reflexes. The incidence of autonomic hyperreflexia during general anesthesia depends on the level of the spinal cord transection. Approximately 85% of patients with a spinal cord transection above the T6 dermatome will exhibit this reflex during general anesthesia. In contrast, it is difficult to elicit this reflex in patients with a spinal cord transection below the T 10 dermatome. Treatment of autonomic hyperreflexia is with ganglionic blocking drugs (e.g., trimethaphan), a-adrenergic receptor antagonists (e.g., phentolamine), direct-acting vasodilators, (e.g., nitroprusside or nitroglycerin), and deep general or regional anesthesia. Patients with autonomic hyperreflexia should not be treated initially with propranolol or other ~-adrenergic receptor antagonists for two reasons. First, bradycardia can be potentiated by ~l-adrenergic receptor blockade; second, ~2-adrenergic receptor blockade in skeletal muscle will leave the a-adrenergic properties of circulating catecholamines unopposed, causing a paradoxical hypertensive response and possible congestive heart failure.
Effects of furosemide administration in the perioperative period include A. Hypernatremia B. Decreased risk for acute tubular necrosis C. Metabolic alkalosis D. Hyperkalemia
C. As with many diuretics, furosemide can cause dehydration and electrolyte imbalance, including loss of potassium, calcium, sodium, and magnesium. Excessive use of furosemide will most likely lead to a metabolic alkalosis due to hypochloremia and hypokalemia.
You are preparing for an emergent mitral valve repair that will need to be done on cardiopulmonary bypass (CPB). While on CPB A. A pulse oximeter can be used to monitor oxygen saturation B. A noninvasive blood pressure cuff can be used to monitor perfusion pressures C. An arterial line can be used to measure perfusion pressures D. None of the above
C. Both pulse oximetry and noninvasive blood pressure cuffs require pulsatile blood flow in order to obtain measurements. These monitors will not be effective during CPB when blood flow is artificially sustained with a more continuous flow. This can also be the case with some patients on left ventricular assist devices, and venous to arterial extracorporeal membrane oxygenation devices, where pulsatile flow is minimal.
When performing an axillary block of the brachial plexus for distal upper extremity surgery, which of the following nerves most often needs to be targeted separately? A. Ulnar B. Radial C. Musculocutaneous D. Median
C. The musculocutaneous nerve typically branches off more proximal to the axillary approach of brachial plexus blockade and is frequently not adequately anesthetized with a traditional axillary block of the plexus (local anesthetics are deposited around the axillary artery). Therefore, the musculocutaneous nerve must be targeted separately when performing an axillary block of the brachial plexus for distal upper extremity surgery.
Variables included in the law of Laplace include all of the variables except: A- radius B- tension C- Pressure D- Density
D- Density The law that states that as a structure expands, its radius, pressure and tension increases. The law of Laplace.
Select the drug with the most potent glucocorticoid property? A- Aldosterone B- Methylprednisone C- Prednisone D- Dexamethosone
D- Dexamethosone
7. Which of the following methods can be used to detect all leaks in the low-pressure circuit of any contemporary anesthesia machine? A. Oxygen flush test B. Common gas outlet occlusion test C. Traditional positive-pressure leak test D. Negative-pressure leak test E. No test can verify the integrity of all contemporary anesthesia machines.
D) Many anesthesia machines have a check valve downstream from the rotameters and vaporizers but upstream from the oxygen flush valve. When the oxygen flush valve button is depressed and the Y-piece (which would be connected to the endotracheal tube or the anesthesia mask) is occluded, the circuit will be filled and the needle on the airway pressure gauge will indicate positive pressure. The positive pressure reading will not fall, however, even in the presence of a leak in the low pressure circuit of the anesthesia machine. If a check valve is present on the common gas outlet, the positive-pressure leak test can be dangerous and misleading. In 1993, the United States Food and Drug Administration (FDA) named the FDA Universal Negative Pressure Leak Test. It was so named because it can be used to check all anesthesia machines regardless of whether they contain a check valve in the fresh gas outlet.
Maternal mortality associated with amniotic fluid embolization is: A-10 - 15% B-20 - 25% C-40 - 45% D-greater than 50%
D-greater than 50% Amniotic fluid embolism is rare with a occurrence of about 1:20,000. However, it carries a very high mortality; some studies quoting as much as 86%. Mortality within the first hour after onset is about 50%.
Maternal mortality associated with amniotic fluid embolization is: A-10 - 15% B-20 - 25% C-40 - 45% D-greater than 50%
D-greater than 50% Amniotic fluid embolism is rare with a occurrence of about 1:20,000. However, it carries a very high mortality; some studies quoting as much as 86%. Mortality within the first hour after onset is about 50%.
During surgical repair of a detached retina, 1 mL of sulfur hexafluoride is injected into the posterior chamber. If the patient is receiving 4% desflurane and a 2:1 ratio of N2O and Ó, the pressure-volume relationship of the bubble will approximately: A-decrease by one third B-remain the same C-double D-triple
D-triple A sulfur hexafluoride gas bubble is sometimes used to support the retina after detachment. Diffusion of nitrous oxide into the bubble will cause expansion as nitrous oxide equilibrates with the gas bubble. A sixty-seven percent nitrous oxide concentration will cause the bubble to triple in its pressure-volume relationship in about 30 minutes and may double the intraocular pressure (IOP). In addition, when nitrous oxide is discontinued, the bubble will return to normal size, causing a fall in IOP and possible extension of the retinal tear. For these reasons, it is recommended that nitrous oxide be discontinued at least 15 minutes prior to the injection of a posterior chamber bubble.
Compensatory mechanisms generally present in patients with congestive heart failure include: A-decreased sympathetic tone B-decreased plasma renin levels C-decreased plasma aldosterone levels D-ventricular hypertrophy
D-ventricular hypertrophy Major compensatory mechanisms present in patients with CHF include increased preload, increased sympathetic tone, activation of the renin-angiotensin-aldosterone system, release of ADH and ventricular hypertrophy.
In a CÓ-absorbent canister, the greatest amount of carbon monoxide is produced by which of the following volatile agents? A. Sevoflurane B. Halothane C. Isoflurane D. Desflurane
D. Desflurane produces the highest amount of carbon monoxide in the CÓabsorbent canister, which can increase carboxyhemoglobin blood concentration. Production of carbon monoxide is increased by using low fresh gas flow rates, high concentrations of volatile agent, and a dry absorbent.
The National Institute for Occupational Safety and Health (NIOSH) recommends limiting operating-room concentration of volatile inhalational agents to ______ ppm: A. 0.2 B. 0.5 C. 1 D. 2
D. 2 NIOSH recommends limiting operating-room concentration of volatile agents to 2 ppm. Minimizing operating-room pollution is important to prevent health-related effects in health-care providers. Waste-scavenging systems are utilized to decrease operating-room pollution
The administration of fresh frozen plasma (FFP) is best indicated for which of the following scenarios? A. A patient on chronic warfarin with a PT of 1.4 times normal for transurethral prostate resection B. A patient with an INR of 1.8 awaiting a liver transplant C. A patient coming to the operating room for an exploratory laparotomy following a gunshot wound D. A patient with hemophilia A undergoing a total knee replacement E. 5 hours into a L1-S1 fusion where the surgeon reports excessive oozing and the coagulation panel has not returned
Fresh fr ozen plasma (FFP) is indicated for the treatment of microvascular bleeding when the International Normalized Ratio (INR), aPPT, or PT is greater than 1.5 times normal. Patients undergoing multilevel spine fusion may develop a consumptive coagulopathy due to blood loss and pooling at the surgical site. If clinical suspicion of microvascular bleeding exists, transfusion of FFP is indicated to maintain hemostasis while awaiting the return of laboratory values. While reversing anticoagulation from warfarin is another indication for FFP administration, especially in acute situations like an expanding subdural hematoma, it would only be necessary for a PT greater than 1.5 times normal. Patients with cirrhosis frequently have elevated INRs of more than 1.5; however, FFP administration is not indicated while waiting for a liver transplantation, as this would cause only a transient improvement in the coagulation profile. FFP maybe indicated in patients awaiting liver transplantation if the INR is very high such that spontaneous intracranial hemorrhage may occur. FFP should not be used as a volume expander or to prophylactically treat coagulopathy in anticipation of massive transfusion. Assessment of clinical hemostasis and/or coagulation studies should help guide treatment in these situations. Patients with hemophilia A should receive specific factor VIII concentrates perioperatively in conjunction with hematology consultation. Cryoprecipitate, not FFP, may be indicated if factor VIII concentrates are unavailable.
Match each pancreatic hormone with the cell type that produces it. a. glucagon b. somatostatin c. insulin d. pancreatic polypeptide 1. beta cells 2. delta cells 3. PP cells 4. alpha cells
Glucagon= alpha cells Insulin= beta cells Somatostatin= delta cells Pancreatic polypeptide= PP cells
Match each oral hypoglycemic agent with its unique risk. a. Glyburide b. Pioglitazone c. Metformin 1. cross sensitivity with sulfa allergy 2. lactic acidosis 3. increased risk for CHF
Glyburide= cross sensitivity with sulfa allergy Pioglitazone= r/f CHF Metformin= lactic acidosis
An 18-year-old patient is brought to the intensive care unit after sustaining a cervical spine injury and quadriplegia during a motor vehicle accident. In the first 24 hours after the injury, the patient is at risk for: (Choose all of the questions that are correct). I. Pulmonary edema 2. Hypothermia 3. Hypotension 4. Autonomic hyperreflexia
I. Pulmonary edema 2. Hypothermia 3. Hypotension Acute spinal cord injury above T4-T6 produces a sympathectomy below the level of injury, which decreases systemic arteriolar and venous vasomotor tone, and abolishes vasopressor reflexes (Le., spinal shock). This pathophysiologic process may continue for up to 6 weeks after injury. As spinal shock resolves, patients with spinal cord injuries cephalad to T4-T6 may develop autonomic hyperreflexia (Le., acute generalized sympathetic hyperactivity as a result of stimulation below the level of injury). Neurogenic pulmonary edema may develop during either spinal shock or autonomic hyperreflexia. Thermoregulation is lost, resulting in poikilothermia, because the hypothalamic thermoregulatory center is unable to communicate with the peripheral sympathetic pathways. In the cool environment of the intensive care unit, spinal cord injury patients are unable to vasoconstrict below the level of injury and, thus, may experience hypothermia. Loss of sympathetic-mediated vasomotor tone also results in hypotension.
Rank the speed of local anesthetic uptake after injection into the following sites (1-fastest, 4-slowest) a. brachial plexus 1. 4 b. caudal 2. 3 c. intercostal 3. 2 d. sciatic 4. 1
Intercostal = 1 caudal = 2 brachial plexus = 3 sciatic = 4 The blood flow to the area where LA is injected affects DOA. If affects the concentration of LA in the blood & the risk of systemic toxicity
Region of the nephrite where most of the filtered sodium is reabsorbed?
Most of filtered Na (65%) is reabsorbed in proximal tubules. Water follows Na in the same proportion. -Loop of henle reabsorbs 20% of Na -distal tubule reabsorbs 5% Na -Collecting duct reabsorbs 5% of Na -Aldosterone fine tunes Na reabsorption in the principal cells i the distal tubules & collecting ducts
Which inhalational agent is a halogenated alkane? (A) Halothane (B) Nitrous oxide (C) Des lurane (D) Sevo lurane
Nitrous oxide is an inorganic anesthetic gas. Desflurane and sevofurane are halogenated with fluorine.
Administration of protamine to a patient who has not received heparin can result in: A. Anticoagulation B. Hypercoagulation C. Profound bradycardia D. Seizure E. Hypertension
Protamine is a basic compound isolated from the sperm of certain fish species and is a specific antagonist of heparin. The dose of protamine is 1.3 mg for each 100 units of heparin. If protamine is administered to a patient who has not received heparin, it can bind to platelets and soluble coagulation factors, producing an anticoagulant effect. There is no evidence that protamine has negative inotropic or chronotropic properties. Some persons (e.g., diabetics taking NPH insulin) may be allergic to protamine. Hypotension may occur when protamine is administered rapidly because it induces histamine release from mast cells.
A volatile anesthetic has a saturated vapor pressure of 360 mm Hg at room temperature. At what flow would this agent be delivered from a bubble-through vaporizer if the carrier-gas flow through the vaporizing chamber is 100 mL/min? A. 30 mL/min B. 60 mL/min C. 90 mL/min D. 120 mL/min E. 150 mL/min
The amount of anesthetic vapor (mL) in effluent gas from a vaporizing chamber can be calculated using the following equation: where VO is the vapor output (mL) of effluent gas from the vaporizer, CG is the carrier gas flow (mUmin) into the vaporizing chamber, SVP anes is the saturated vapor pressure (mm Hg) of the anesthetic gas at room temperature, and Pb is the barometric pressure (mm Hg)
A. The sciatic nerve supplies all of the motor innervation and the majority of the sensory innervation to the lower extremities below knee except the medial side of the lower extremity that is innervated by the saphenous nerve
The foot is supplied mainly by which of the following nerve(s)? A. Sciatic nerve B. Obturator and tibial nerves C. Femoral and lateral femoral cutaneous nerves D. Saphenous and common peroneal nerves.
When the SaÓ is 90%, what is the PaÓ? A. 50 mm Hg B. 60 mm Hg C. 70 mm Hg D. 80 mm Hg
Under idea conditions of normal pH, 2,3 DPG, and temp, the SaÓ of 90% corresponds to a PaÓ = 60 mmHg.
Re-order the list of inhaled agents below from highest vapor pressure to lowest (Highest vapor pressure agent at top of list): 1.Isoflurane 2.Sevoflurane 3.Nitrous Oxide 4.Desflurane
Vapor Pressure of Agents 3. Nitrous Oxide 4. Desflurane 1. Isoflurane 2. Sevoflurane At 20o C, the highest vapor pressure of the inhaled agents is possessed by nitrous oxide (38,700 mm Hg), followed by desflurane (669 mm Hg), isoflurane (238 mm Hg) and sevoflurane (157 mm Hg).
Absolute contraindications to the use of epidural anesthesia in the parturient include: (Select 2) A- inability of the patient to cooperate B- herniated lumbar disc C- multiple sclerosis D- patient refusal E- history of previous cesarean section F- aortic regurgitation
[A, D] Inability of the patient to cooperate, patient refusal Absolute contraindications to epidural anesthesia/analgesia in the parturient include infection over the injection site, coagulopathy, thrombocytopenia, marked hypovolemia, true local anesthetic allergy, patient refusal and inability of the patient to cooperate. Preexisting neurological disease and back disorders are relative contraindications. Patients with aortic regurgitation usually benefit from the reduction in afterload seen after neuraxial anesthesia.
What criteria are used to clinically diagnose chronic bronchitis? a. Mucous gland hypoplasia b. Mucous gland hyperplasia c. Mucosal edema leading to restrictive airway disease. d. Productive cough on most days of 3 consective months for at least 2 consecutive years.
[D] Productive cough on most days of 3 consective months for at least 2 consecutive years. (Chronic bronchitis is defined as an inflammatory process of the main airways that waxes and wanes and may continue for a long period of time. The disgnostic criteria are based on the presence of a cough with excess mucus production lasting > 3 months in at least 2 consecutive years unrelated to any other disease).
The triad of obesity, hypertension and type 2 diabetes is called what ? a - metabolic syndrome b- Prader-Willi syndrome c- emenating gut syndrome d- Pickwickian sydrome
a - metabolic syndrome
Which of the following are reduced with obesity? (select 2) a. vital capacity b. closing capacity c. expiratory reserve volume d. residual volume
a. vital capacity c. expiratory reserve volume -decreased FRC (decreased ERV & RV constant) -closing capacity unchanged
A patient with a dibucaine number of 20 received succinylcholine. This patient: a. will be paralyzed for 8 hours b. fails to produce pseudocholinesterase in sufficient quantity c. is heterozygous for pseudocholinesterase d. should receive FFP
a. will be paralyzed for 8 hours Homozygous for atypical PChE and will remain paralyzed for 4-8hours -whole blood, FFP, or purified human cholinesterase will restore plasma PChE levels in pt with atypical variant, post op mechanical ventilation & sedation is treatment of choice--safest and least expensive
Choose 4 pathways of drug metabolism: a- biotransformation b- reduction c- demethylation d- conjugation e- oxidation f- deamination g- hydrolysis h- phosphorylation
b,d,e,g [Drug metabolism typically involves alteration to the physical or chemical properties of the drug to make that drug more attractive to the physiological process to facilitate the drug removal. Drug metabolism i accomplished via four methods: oxidation, reduction, hydrolysis, and conjugation; the first methods typically prepare a drug to be further acted upon by the fourth, conjugation.
The largest fraction of carbon dioxide in the blood is in the form of : A-carbamino compounds B-bicarbonate C-dissolved gas D-carboxyhemoglobin
b-bicarbonate Nearly 90% of carbon dioxide in the blood is in the form of bicarbonate.
Which agent can produce tissue necrosis if it is administered into an artery? a. etomidate b. thiopental c. dexmedetomidine d. propofol
b. thiopental
A patient received a citrated, non-particulate antacid but the case has been delayed. How long after the inital dose, should a second dose be considered? a- 15 mins b - 30 mins c- 60 mins d- 120 mins
c- 60 mins Citrate anatacids increase the pH within 15 mins and last up to 7 hours. Some patients have rebound acidity so it is recommended to re-dose after 1 hour.
Following a motor vehicle accident, a 25-year-old male patient is brought to the operating room for repair of facial lacerations and fractures, and abdominal exploration. The patient is extremely micrognathic and weighs 328 pounds. Acceptable techniques for securing the airway include: (Choose all of the questions that are correct). 1. Awake fiberoptic intubation. 2. Blind nasal intubation . 3. Awake tracheostomy. 4. Direct laryngoscopy with rapid sequence induction.
1. Awake fiberoptic intubation 3. Awake tracheostomy. Nasal intubation should be avoided in patients with suspected basal skull (e.g., disruption of the cribriform plate of the ethmoid bone) fractures or sinus injuries. Because approximately 10% of head injury patients have associated cervical spine injuries, it is prudent to assume that all head injury patients have coexisting cervical spine injury until proven otherwise. Additionally, the patient described in this question may have abnormal airway anatomy because of extreme micrognathia, facial injuries, and obesity. Taken together, direct laryngoscopy with rapid sequence induction is probably not an acceptable technique for securing this patient's airway. In contrast, awake intubation by direct or fiberoptic laryngoscopy or performance of tracheostomy are considered appropriate techniques for tracheal intubation of this patient.
Treatment(s) for von Willebrand's disease may include :(Pick all that apply) 1. Desmopressin acetate (DDAVP) 2. Cryoprecipitate 3. Factor VIII concentrate 4. Factor IX concentrate
1. Desmopressin acetate (DDAVP) 2. Cryoprecipitate 3. Factor VIII concentrate Factor VIII is a complex of two parts, the procoagulant factor VIII and von Willebrand's factor (vWF). The procoagulant factor VIII is deficient in hemophilia A. In von Willebrand's disease there is a deficiency of vWF, which is important for adequate factor VIII activity and platelet function. These patients have prolonged bleeding times despite normal platelet counts. This disease is transmitted as an autosomal dominant trait and can affect both sexes. There are three major types of von Willebrand's disease. Type I (70% to 80% of all von Willebrand's disease) has a quantitative deficiency for vWF (i.e., level <40%). Type II (20% to 30% of von Willebrand's disease) has a qualitatively abnormal vWF (the actual level may be normal or decreased). Type II has several subtypes, including types IIA, lIB, and lIN. Type ill is very rare (about one per million) and has extremely low or undetectable levels of vWF. Treatment depends upon the type of von Willebrand's disease. The synthetic vasopressin analogue desmopressin (DDAVP) causes the release of vWF in type I and type llA patients and is quite effective in treating bleeding. However, DDAVP in contraindicated in type lIB because it can cause severe thrombocytopenia. Virus-inactivated factor vrn concentrate known to contain vWF is used in type III and type I patients when DDAVP has failed. Fresh frozen plasma and cryoprecipitate also contains vWF and have been used.
Anesthetics that increase ICP include:(Choose all of the questions that are correct). 1. Enflurane 2. N20 3. Halothane 4. Fentanyl-droperidol (lnnovar)
1. Enflurane 2. N20 3. Halothane In general, all volatile anesthetics are vasodilators that, with normocapnia, will increase CBF, CBV, and ICP. The order of vasodilator potency is approximately halothane » enflurane > isoflurane = sevoflurane = desflurane. As discussed in the response to question 731, opioids have little, if any, effect on CMR, CBF, or ICP. The effect of N20 on CBF, CBV, and ICP is controversial. In a number of animal and human studies, N20 increased CBF by 35% to 103%. Conversely, in other animal studies, N20 was consistently found to have only minimal effects on CBF. Differences between species may be one factor contributing to these conflicting results. Because N20 appears to increase CBF and CBV in humans, it seems prudent to discontinue N20 in patients in whom intracranial hypertension is not responsive to other therapeutic maneuver.
Drugs useful in the treatment of hemolytic transfusion reactions include 1. Furosemide (loop diuretic) 2. Sodium bicarbonate 3. Mannitol 4. Diphenhydramine
1. Furosemide (loop diuretic) 2. Sodium bicarbonate 3. Mannitol Hemolytic transfusion reactions can be immediate (at the time of transfusion) or delayed (a few days after the transfusion). In either case, with hemolysis free hemoglobin and other cellular materials are released into the serum. Signs and symptoms vary but include fever, chills, pain (at the infusion site, chest, back, abdomen), nausea, hypotension, shock, coagulopathy, hemoglobinuria, and later oliguria, renal failure, and in some cases death. Many of these signs are masked by general anesthesia. The first step in treating a hemolytic reaction is to stop the transfusion. Because most cases of hemolytic transfusion reaction involve clerical error, type O-negative blood is administered when blood is urgently needed (i.e., life-threatening situation) until further workup can be completed. The goal of treatment is both preventive (to avoid acute renal failure) and symptomatic. Acute renal failure may develop as a result of precipitation of free hemoglobin in the form of acid hematin in the distal renal tubules causing mechanical blockage and acute renal failure. To maintain renal function and good dilute urine output, generous administration of intravascular fluids, diuretics, and mannitol is recommended. In addition, sodium bicarbonate is administered to alkalinize the urine to prevent precipitation of acidic hematin. Hypotension is treated with fluids and dopamine if needed. Fresh frozen plasma, platelets, and cryoprecipitate may be needed if a coagulopathy develops. In cases of mild nonhemolytic allergic (urticarial) transfusion reactions, diphenhydramine is helpful. In severe forms of allergic transfusion reactions, epinephrine and/or corticosteroids may be needed.
The seizure threshold for local anesthetics is raised by: (Choose all that apply). 1. Hypokalemia 2. Hyperoxia 3. Hypocarbia 4. Acidosis
1. Hypokalemia 3. Hypocarbia Hyperventilation of the lungs and hypocarbia decrease cerebral blood flow, thus reducing delivery of local anesthetic to the brain. The alkalosis and hypokalemia that occur as a result of hyperventilation lead to hyperpolarization of the resting transmembrane potential of neurons, thus increasing the seizure threshold for local anesthetics. Conversely, acidosis and hypercarbia decrease the seizure threshold for local anesthetics. Hyperoxia does nothing to prevent seizures.
Anesthetic agents that both decrease the amplitude and increase the latency of SSEPs include::(Choose all of the questions that are correct). 1. Isoflurane 2. Etomidate 3. Diazepam 4. Nitrous oxide
1. Isoflurane 3. Diazepam Diazepam, like isoflurane, decreases amplitude and increases latency of the SSEP waveform
Which of the following agents is(are) effective topical anesthetics when applied to mucous membranes? (Choose all that apply). 1. Lidocaine 2. Cocaine 3. Tetracaine 4. Procaine
1. Lidocaine 2. Cocaine 3. Tetracaine Lidocaine, tetracaine, and cocaine are all effective topical anesthetics when applied to mucous membranes. Cocaine is unique among local anesthetics in that it is a vasoconstrictor. Procaine penetrates the mucous membranes poorly and is not useful as a topical agent
Conditions that are associated with cerebral aneurysms include:(Choose all of the questions that are correct). 1. Polycystic kidney disease 2. Fibromuscular dysplasia 3. Coarctation of the aorta 4. Hypertension
1. Polycystic kidney disease 2. Fibromuscular dysplasia 3. Coarctation of the aorta 4. Hypertension There are a variety of medical conditions associated with cerebral aneurysms and subsequent subarachnoid hemorrhage (SAH). These include hypertension, coarctation of the aorta, polycystic kidney disease, and fibromuscular dysplasia. Additionally, a recent study reported a significant association between cigarette smoking and SAH.
Branches of the sciatic nerve include: (Choose all that apply). 1. Posterior tibial 2. Common peroneal 3. Sural 4. Saphenous
1. Posterior tibial 2. Common peroneal 3. Sural There are four main nerves in the lower extremity: the sciatic, femoral, obturator, and lateral femoral cutaneous. The sciatic nerve is the largest of these and divides into the posterior tibial nerve and common peroneal nerve at the popliteal fossa. The common peroneal nerve divides further into the deep and superficial peroneal nerves. The tibial nerve divides into the posterior tibial and sural nerves. Thus, four of the five nerves that provide sensory innervation to the ankle arise from the sciatic nerve: deep peroneal, superficial peroneal, posterior tibial, and sural. The saphenous nerve is a branch of the femoral nerve and stands alone in this regard.
The incidence of postdural puncture headache is increased in which of the following situations? (Choose all that apply) 1. Pregnancy 2. Young age 3. Use of large-bore spinal needle 4. Use of paramedian instead of midline approach
1. Pregnancy 2. Young age 3. Use of large-bore spinal needle Patients who are at increased risk of headache after dural puncture include parturients and young patients. Use of large-bore needles and glucose-containing local anesthetics also can raise the risk of spinal headache. Spinal headaches result from leakage of CSF through the dural sheath. The headache is typically frontal or occipital in location and is worsened by sitting or standing up. There is some evidence that the incidence of spinal headache is less after a dural puncture made through the paramedian approach.
Epinephrine is effective in increasing the clinical duration of action of (Choose all that apply). 1. Procaine 2. Lidocaine 3. Tetracaine 4. Etidocaine
1. Procaine 2. Lidocaine 3. Tetracaine Epinephrine or phenylephrine is frequently added to local anesthetic solutions to produce vasoconstriction. This decreases systemic absorption of the local anesthetic and prolongs the duration of action of the local anesthetic. The extent to which epinephrine prolongs the block depends on both the site of injection and the specific local anesthetic. These beneficial effects are limited when vasoconstrictors are used with epidural etidocaine and bupivacaine.
Etomidate: (Choose all of the questions that are correct). 1. Reduces CMR02 2. Is a direct cerebral vasoconstrictor 3. Reduces CBF 4. Abolishes CÓ reactivity
1. Reduces CMR02 2. Is a direct cerebral vasoconstrictor 3. Reduces CBF The cerebral pharmacologic profile of etomidate is similar to that of thiopental in that it produces a dose-related decrease in the CMR and CBP (via direct cerebral vasoconstriction and coupling to decreased CMR). As noted after barbiturate administration, intravenous etomidate does not disturb cerebral autoregulation or CÓ reactivity.
A 62-year-old male patient presents for resection of a supratentorial meningioma. Intravenous induction with propofol is planned. Propofol shares which property(properties) with sodium thiopental?(Choose all of the questions that are correct). 1. Reduction in CMR 2. Reduction in CBP 3. Reduction in CBV 4. Reduction in ICP
1. Reduction in CMR 2. Reduction in CBP 3. Reduction in CBV 4. Reduction in ICP The effects of propofol on cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral metabolism (CMR), and intracranial pressure (ICP) are quite similar to those of barbiturates, that is, propofol causes reductions in CBF, CBV, CMR, and ICP (provided ventilation is not depressed.
Disadvantage(s) of the Bain anesthesia breathing circuit include. (Select all the correct answers). 1. Requirement for high fresh-gas inflow rates when used during spontaneous ventilation 2. Increased resistance to breathing 3. Unrecognized disconnection or kinking of the inner tube 4. Inability to scavenge waste anesthetic gases
1. Requirement for high fresh-gas inflow rates when used during spontaneous ventilation 2. Increased resistance to breathing 3. Unrecognized disconnection or kinking of the inner tube. The Bain anesthesia breathing circuit has an adjustable pressure-relief valve located near the reservoir bag. This design allows for ease of scavenging waste anesthetic gasses. The other choices are disadvantages of this breathing system.
Which of the following intravenous fluids can be used to decrease the viscosity of packed RBCs? (Pick all that apply) 1. Saline 2. D5W (5% dextrose in water) 3. 5% albumin 4. Lactated Ringer's solution
1. Saline 3. 5% albumin Both saline and 5% albumin can be used to dilute blood to make it easier to infuse. Five percent dextrose in water can cause RBC hemolysis. Lactated Ringer's solution, which contains calcium, may initiate coagulation and should not to be used to dilute RBCs.
Through which of the following would a spinal needle pass during a midline placement of a subarachnoid block in the L3-4lumbar space? (Choose all that apply) 1. Supraspinous ligament 2. Interspinous ligament 3. Ligamentum flavum 4. Anterior longitudinal ligament
1. Supraspinous ligament 2. Interspinous ligament 3. Ligamentum flavum
One minute following an inter scalene block, a 62kg pt. has a seizure. How much 20% lipid emulsion should you administer?
1.5ml/kg 1.5 x 62 = 93ml
The risk of paradoxical air embolism is increased in patients with a patent foramen ovale. The incidence of patent foramen ovale in the adult population is approximately: ___________ % (Enter numerical answer in box below. Click 'Next' when completed.)
10 - 25% The incidence of venous air embolism is highest during sitting crainotomies, with an incidence of 20 - 40%. The risk of paradoxical venous air embolization is increased in patients with patent foramen ovale, which has a reported incidence of 10 - 25% in the adult population.
The risk of paradoxical air embolism is increased in patients with a patent foramen ovale. The incidence of patent foramen ovale in the adult population is approximately: (Enter numerical answer in box below. Click 'Next' when completed.) %__________
10 - 25% The incidence of venous air embolism is highest during sitting crainotomies, with an incidence of 20 - 40%. The risk of paradoxical venous air embolization is increased in patients with patent foramen ovale, which has a reported incidence of 10 - 25% in the adult population.
At what plasma concentration would you expect lidocaine to produce seizures? (enter your answer as a whole number in mcg/ml)
10-15 mcg/ml Lidocaine can cause cardiac and neurologic toxicity. seizures are most likely to being when Cp= 10-15
In a 6-year-old, the appropriate length of an endotracheal tube from distal tip to incisors is: (Enter numerical answer in box below.) __________ cm
15 - 16.5 cm Several formulas exist to estimate the length of ETT insertion in patients aged 2 to 12 years. One of the most frequently used is: Age/2 +12
The loss of ventricular filling as a result of acute atrial fibrillation is approximately: (Enter numerical answer in box below. Click 'Next' when completed.) _______%
15-25% Passive flow accounts for about 75 - 85% of ventricular filling. The remaining 15 - 25% occurs as a result of atrial contraction, which is lost during atrial fibrillation.
The loss of ventricular filling as a result of acute atrial fibrillation is approximately?: (Enter numerical answer in box below. Click 'Next' when completed.)
15-25% Passive flow accounts for about 75 - 85% of ventricular filling. The remaining 15 - 25% occurs as a result of atrial contraction, which is lost during atrial fibrillation.
Order each drug in terms of its glucocorticoid potency (1=most) a. Aldosterone b. methylprednisolone c. cortisol c. dexmethasone
1= Dexmethasone 2= Methylprednisolone 3= Cortisol 4= Aldosterone
Rank each nerve fiber according to sensitivity. (1 most, 4 least) Large diameter A fibers B fibers Small diameter A fibers C fibers
1= Large A fibers 2= small A fibers 3= B fibers 4= C fibers
Assuming the amount of injected LA is the same, rank each injection site according to LA Cp that results (1 highest CP, 5 lowest) Brachial plexus caudal interpleural intercostal
1= interpleural 2= intercostal 3= caudal 4= brachial plexus
Rank anesthetic agents according to their potency (1 most, 4 least) 1-sevoflurane 2-isoflurane 3-N2O 4-desflurane
1= isoflurane 2= sevoflurane 3= desflurane 4= N2O
During intraoperative fluoroscopy, the patient receives 32 mR at a distance of 1 foot from the fluoroscopy tube. The maximum radiation dose possible to the anesthesia provider, standing at a distance of 4 feet from the fluoroscopy tube is: (Enter numerical answer in box below). _________ mR
2 mR Increasing the distance from the source of radiation is a very effective means of reducing dose. Dose rates increase or decrease according to the inverse square of the distance from the source. Using the inverse square law formula: I1D12 = I2D22 I = intensity, D = distance (32 mR)(1 ft)2 = (I2)(4 ft)2; I2 = 2 mR
Pick 2 of the following which do NOT cause SPÓ artifact. 1) fetal Hgb 2) bilirubin 3) Hgb < 7 4) carboxyhemoglobin 5) methemoglobin
2) bilirubin 3) Hgb < 7
Which of the following observations, after nerve injury, is correctly paired with the appropriate nerve? (Choose all that apply). 1. Inability to flex the forearm-radial nerve 2. Numbness in the index finger-median nerve 3. Inability to extend the forearm-musculocutaneous nerve 4. Numbness in the little finger-ulnar nerve.
2, 4 To check the setup of a brachial plexus block, one can perform the four P's (push, pull, pinch, pinch). Have the patient push or extend the forearm (triceps muscle is innervated by the radial nerve), pull or flex the forearm (biceps muscle is innervated by the musculocutaneous nerve), pinch the index or second finger (median nerve), pinch the little finger (ulnar nerve)
A 74-year-old patient undergoes a lumbar sympathetic block to improve blood flow after frostbite. Findings that suggest a successful lumbar sympathetic block include (Choose all that apply). 1. Inability to dorsiflex foot 2. Blushing in the toes 3. Numbness from the knee to the toes 4. Temperature increase in the legs
2,4 The completeness of a lumbar sympathetic block can be ascertained by skin temperature measurements and increases in blood flow. The latter can be determined by a number of techniques, including laser Doppler flowmeter, occlusion skin plethysmography, transcutaneous oxygen electrodes, and mass spectrometry. Numbness in the leg and inability to move it suggest an accidental subarachnoid or epidural injection, a rare but possible complication of this block.
The markings on compressed-gas cylinders designate:(Choose all that apply) 1. The contents of the cylinder 2. The maximal permissible pressure allowed within the cylinder 3. Dates of prior transportation of the cylinder 4. The size of the cylinder
2,4 The letters and numbers imprinted near the top of compressed-gas cylinders refer to the Department of Transportation (DOT) specification number, service pressure number, serial numbers of the purchaser, user, or manufacturer of the cylinder, the maximal permissible pressure, and the original and retest dates for pressure tolerance. In addition, the cylinders are designated by a letter indicating the size of the cylinder. The contents of the cylinder are designated by a detachable label and the color of the cylinder (green for 02' blue for N20, gray for CÓ, and yellow for air
Blood is routinely screened for which of the following? ( Choose all that apply). 1. Antibodies against hepatitis A 2. Antibodies against hepatitis B 3. Antibodies against CMV 4. Antibodies against human T-cell leukemia virus type I
2. Antibodies against hepatitis B 4. Antibodies against human T-cell leukemia virus type I Currently, eight screening tests for infectious disease are performed on each unit of donated blood. These tests are used to screen for syphilis, human immunodeficiency virus (HIV-l, HIV-2, HIV p24 antigen), human T-Iymphotropic virus (HTLV-l and HTLV-2), hepatitis B, and hepatitis C. The presence of antibodies against CMV and hepatitis A is not routinely determined.
Para-aminobenzoic acid is a metabolite of:(Choose all that apply) 1. Mepivacaine 2. Benzocaine 3. Bupivacaine 4. Tetracaine
2. Benzocaine 4. Tetracaine Para-aminobenzoic acid is a metabolite of the ester-type local anesthetics. Local anesthetics may be placed into two distinct categories based on their chemical structure: ester or amide. All of the amides contain the letter "i" twice, once in "caine" and once elsewhere in the name (e.g., lidocaine, etidocaine, prilocaine, mepivacaine, and bupivacaine). These are metabolized in the liver. The ester local anesthetics are cocaine, procaine, chloroprocaine, tetracaine, and benzocaine. These drugs are metabolized by the enzyme pseudocholinesterase found in the blood. Their half-lives in blood are very short, about 60 seconds. Para-aminobenzoic acid is a metabolic breakdown product of ester anesthetic and is responsible for allergic reactions in some individuals.
Local anesthetics metabolized by ester hydrolysis include: (Choose all that apply) 1. Lidocaine 2. Cocaine 3. Mepivacaine 4. Tetracaine
2. Cocaine 4. Tetracaine Cocaine and tetracaine are ester-type local anesthetics and are metabolized in part by ester hydrolysis in plasma by pseudocholinesterase
During spontaneous breathing through a circle system, the anesthesia bag contracts during inspiration. To flow from the anesthesia bag to the patient, Ó must pass through which of the following devices?(Select all the correct answers). 1. Fresh gas inlet (common gas outlet) 2. CÓ absorber 3. Ventilator bellows 4. Inspiratory valve
2. CÓ absorber 4. Inspiratory valve During spontaneous breathing through a circle system, Ó would pass through the CÓ absorber and the inspiratory valve on its way from the anesthesia bag to the patient.
Causes of sickling in patients with sickle cell anemia include (Choose all that apply) 1. Hyponatremia 2. Dehydration 3. Metabolic alkalosis 4. Hypothermia
2. Dehydration 4. Hypothermia Sickle cell anemia is an inherited disease that affects approximately 0.3% to I % of the black population in the United States. Affected patients are homozygous for hemoglobin S such that 70% to 98% of the hemoglobin found in their RBes is of the unstable S type, resulting in severe hemolytic anemia. Factors that favor the formation of sickle cells include arterial hypoxemia, acidosis, dehydrat.ion, and reductions in body temperature.
Five days after clipping of a cerebral aneurysm, a 68-year-old female patient develops clinical evidence of vasospasm. Therapy that is useful in the treatment of cerebral vasospasm includes :(Choose all of the questions that are correct). 1. Blood pressure reduction 2. Hemodilution 3. Diuretics 4. Calcium channel blockers
2. Hemodilution 4. Calcium channel blockers After subarachnoid hemorrhage (SAH), the incidence and severity of cerebral vasospasm have been reported to correlate with the amount and location of blood in the calvarium. Angiographic evidence of vasospasm has been noted in up to 70% of SAH patients. However, clinically significant vasospasm occurs in only 20% to 30% of SAH patients. The incidence peaks approximately 7 days after SAH. Calcium channel blockers (e.g., nimodipine) decrease the morbidity and mortality associated with vasospasm, but investigators have been unable to demonstrate any significant change in the incidence or severity of vasospasm. This suggests that the beneficial effects of nimodipine may be related to inhibition of primary and secondary ischemic cascades, rather than direct cerebral vasodilation. Treatment of vasospasm also includes "triple H therapy" (i.e., hypervolemia, induced hypertension, and hemodilution) and cerebral angioplasty. The rationale of induced hypervolemia and hypertension is that ischemic regions of brain have impaired autoregulation and, thus, CBF is perfusion pressure dependent. Hemodilution is thought to increase blood flow through the cerebral microcirculation (because of improved rheology and reactive hyperemia). One argument against hemodilution is that increases in CBF are offset by concomitant decreases in the oxygen-carrying capacity. Taken together, blood pressure reductions and diuretic use are incorrect responses to this question.
In patients with increased ICP, hyperventilation is typically limited to a Pacó of 25 mm Hg because additional hyperventilation: (Choose all of the questions that are correct). 1. Is virtually impossible 2. May result in clinically significant hypokalemia 3. Could result in paradoxical cerebral vasodilation 4. Could result in cerebral ischemia.
2. May result in clinically significant hypokalemia 4. Could result in cerebral ischemia.
During an emergency cesarean section, a 25-year-old primiparous female begins to bleed briskly. Blood that has undergone the first phase of crossmatch is brought to the operating room. A transfusion reaction involving which of the following antibodies is possible if this blood were transfused at this time? (Pick all that apply) 1. ABO 2. Rh 3. MN, P, and Lewis 4. Kell, Duffy, and Kidd
2. Rh 4. Kell, Duffy, and Kidd Crossmatching blood involves a "trial transfusion" of donor RBCs with recipient serum. It occurs in three phases. The first phase (immediate phase) takes less than 5 minutes to perform and mainly detects ABO, as well as MN, P, and Lewis incompatibilities. The second phase (incubation phase) mainly checks for Rh incompatibility and takes about 45 minutes to perform. The third phase (antiglobulin phase) detects incompatibilities to the Kell, Duffy, and Kidd antigens.
Which of the following nerves blocked at the ankle do not contain motor fibers? 1. Posterior tibial nerve 2. Saphenous nerve 3. Deep peroneal nerve 4. Sural nerve
2. Saphenous nerve 4. Sural nerve Five nerves are blocked when performing an ankle block. The saphenous, superficial peroneal, and sural nerves are all sensory below the ankle. At the ankle, stimulation of the posterior tibial nerve causes flexion of the toes by stimulating the flexor digitorum brevis muscles and abduction of the first toe by stimulating the abductor hallucis muscles. The posterior tibial nerve also is sensory to most of the plantar part of the foot. At the ankle, stimulation of the deep peroneal nerve causes extension of the toes by stimulating the extensor digitorum brevis muscles. The deep peroneal nerve has a small sensory branch for the first interdigital cleft. From the practical standpoint, many anesthesiologists perform a purely infiltration block of these nerves. If a nerve stimulator is used, it is mainly used to find the posterior tibial nerve, which can be hard to anesthetize if small volumes of local anesthetic are administered. The posterior tibial nerve can be difficult to stimulate in diabetics with diabetic neuropathy.
Factor(s) that determine the proportion of local anesthetic that exists in the un-ionized (freebase) and ionized (cation) forms include: (Choose all that apply) 1. Local anesthetic concentration 2. Tissue pH 3. Local anesthetic volume 4. pKa of the local anesthetic
2. Tissue pH. 4. pKa of the local anesthetic. Local anesthetics are weak bases with pKas ranging from 7.6 to 8.9. A low pH will result in the formation of the ionized species because more protons (hydrogen ions) are available to bind to the nitrogen atoms in the local anesthetics. Local anesthetic concentration and volume have nothing to do with the fraction of anesthetics in the ionized form.
Operation at high altitudes will affect the accurate function of which of the following devices? (Select all the correct answers). I. Mechanical ventilator 2. Vaporizer 3. CÓ absorber 4. Ó rotameter
2. Vaporizer 4. Ó rotameter Changes in atmospheric pressure will affect gas density. Because rotameters and vaporizers are calibrated at an atmospheric pressure of 760 mm Hg, use of these devices at an atmospheric pressure other than 760 mm Hg will alter their accuracy
The number of dichotomous divisions of the tracheobronchial tree from the trachea to the alveolar sacs is approximately: ___
20 - 25 Dichotomous division, each branch dividing into two smaller branches, of the tracheobronchial tree is estimated to involve 20 - 25 divisions.
A patient weighs 176 lbs. & stands 74 in. tall. Calculate the patient's BMI.
22 176/2.2= 80kg 74 x 2.54= 187.96--> 1.8796m ^2= 3.53289616 80/3.53289616= 22.64
During an anterior-posterior spinal fusion, in a 70-kg patient, the laboratory reports an intraoperative hematocrit of 21% with a hemoglobin of 7g/dL. Two units of packed red blood cells are administered over the course of 30 minutes. Upon completion of the transfusion, the anticipated hematocrit will be approximately: (Enter numerical answer in box below _______%
25 - 27% A commonly used rule of thumb states that each unit of PRBCs increases the hemoglobin 1 g/dL and the hematocrit 2% to 3%.
During rapid-sequence induction, cricoid pressure is applied to reduce the incidence of regurgitation. After loss of consciousness, the recommended amount of downward force applied to the cricoid cartilage is: _______ KG
3.0 - 4.4 kg Using cricoid yolk studies, the optimum force necessary to effectively occlude the esophagus without obstruction of the trachea is between 30 and 44 Newtons (3.0 - 4.4 kg). It is recommended that 2 kg of force be applied prior to loss of consciousness and that pressure be increased to 4 kg of force after loss of consciousness.
After administering an IV drug that distributes into a 1 compartment model, the patient's serum contains 6.25% of the original dose. How many half-lives have elapsed?
4 Elimination 1/2 life (t1/2) is the time required for the drug's plasma concentration to the decline by 50% 1= 50% 2= 25% 3= 12.5% 4= 6.25% 5= 3.125%
True statements concerning a closed scavenging system interface include which of the following?(Choose all that apply) 1. Failure to connect the system interface to the wall suction will result in barotrauma to the patient 2. Excessive wall suction will result in hypoventilation of the lungs 3. The scavenging system reservoir bag will distend during inspiration 4. The scavenging system reservoir bag will distend during expiration
4 ONLY, A scavenging system with a closed interface is one in which there is communication with the atmosphere through positive- and negative-pressure relief valves. The negative-pressure relief valve prevents the transfer of negative pressure from wall suction to the patient breathing circuit. The scavenging system reservoir bag should distend during expiration, not inspiration.
The pin-index safety system prevents:(Choose all that apply) I. Attachment of gas administration equipment to the wrong gas line. 2. Delivery of a hypoxic mixture from the rotameters to the patient. 3. Delivery of the wrong gas from the central supply source. 4. Incorrect yoke to compressed-gas cylinder connections.
4 only The pin-index safety system consists of two pins projecting from the inner surface of the yoke corresponding to holes in the valve casing of the compressed-gas cylinder. This system prevents the incorrect attachment of compressed-gas cylinders to the anesthesia machine
"Postspinal" headaches (Choose all that apply). I. Usually occur immediately following dural puncture 2. Are relieved 8 to 12 hours after an epidural blood patch is performed 3. Occur more frequently in nonpregnant compared with pregnant patients 4. Can be associated with neurologic deficits
4, Postspinal headaches are characterized by frontal or occipital pain, which worsens with sitting and improves with reclining. Postspinal headaches may be associated with neurologic symptoms such as diplopia, tinnitus, and reduced hearing acuity. The etiology of postspinal headaches is unclear; however, they are believed to be caused by a reduction in CSF pressure and resulting tension on meningeal vessels and nerves (which results from leakage of CSF through the needle hole in the dura mater). Factors associated with an increased incidence of postspinal headaches include pregnancy, size and type of needle used to perform the block, age of the patient, the number of dural punctures. Conservative therapy for a postspinal headache include bed rest, analgesics, and oral and intravenous hydration. If conservative therapy is not successful after 24 to 48 hours, it is recommended that an epidural "blood patch" with 10 to 20 mL of the patient's blood be performed. An epidural "blood patch" provides prompt relief of the postspinal headache.
True statements concerning local anesthetics include which of the following? (Choose all that apply). I. The un-ionized form of a local anesthetic binds to the nerve membrane to actually block conduction 2. If one node of Ranvier is blocked, conduction will be reliably interrupted 3. The ability of a local anesthetic to block nerve conduction is directly proportional to the diameter of the fi ber 4. The presence of myelin enhances the ability of a local anesthetic to block nerve conduction
4, The un-ionized form of the local anesthetic traverses the nerve membrane whereas the ionized form actually blocks conduction. About three nodes of Ranvier must be blocked to achieve anesthesia. The ability of a local anesthetic to block conduction is inversely proportional to the diameter of the fiber. The presence of myelin enhances the ability of a local anesthetic to block conduction, as does rapid firing.
Turbulent gas flow through a tube increases: (Choose all that apply) 1. Linearly with the pressure gradient down the tube 2. Linearly with the density of the gas 3. To the fourth power of the radius of the tube 4. Approximately to the square of the radius of the tube
4, The Hagan-Poiseuille Law of Friction does not apply when gas flow through a tube is turbulent. Turbulent gas flow increases approximately with the square of the radius of the tube (instead of the radius raised to the fourth power), the square root of the pressure gradient down the tube, and the reciprocal of gas density (instead of gas viscosity)
Nerves that originate from the sacral plexus include (Choose all that apply). 1. Femoral nerve 2. Obturator nerve 3. Lateral femoral cutaneous nerve 4. Sciatic nerve
4, The femoral, obturator, and lateral femoral cutaneous nerves arise from the lumbar plexus, whereas the sacral plexus gives rise to the sciatic nerve and its branches, the common peroneal, deep and superficial peroneal, posterior tibial, and sural
Autoregulation is abolished by: (Choose all of the questions that are correct). 1. Hyperbaric oxygen 2. Cardiopulmonary bypass with core temperature 27°C 3. Chronic hypertension 4. 3% isofluran
4. 3% isofluran Cerebral autoregulation is disturbed in a number of diseases (e.g., acute cerebral ischemia, mass lesions, trauma, inflammation, prematurity, neonatal asphyxia, and diabetes mellitus). The final common pathway of dysfunction, in its most extreme form, is termed vasomotor paralysis. Autoregulation is not, or minimally, affected by hyperoxia. During normothermic and moderate hypothermic (i.e., approximately 27°C) cardiopulmonary bypass, autoregulation is well preserved. Chronic hypertension causes a rightward shift of the autoregulation curve toward higher upper and lower cerebral perfusion pressure limits (also see explanation to question 778). Autoregulation is impaired by volatile anesthetics (e.g., isoflurane). At greater than 2 MAC, autoregulation is abolished
The duration of epidural anesthesia is affected by : (Choose all that apply). 1. Height of patient 2. Age of patient . Weight of patient 4. Addition of epinephrine (1 :200,000) to the local anesthetic
4. Addition of epinephrine (1 :200,000) to the local anesthetic Height, age, and weight of the patient do not determine the duration of epidural anesthesia. The concentration, dose, and volume of local anesthetic and whether a vasoconstrictor is added to the local anesthetic are important factors in determining the duration of action of epidural blockade.
The CBF autoregulatory curve is shifted to the right by:(Choose all of the questions that are correct). 1. Hypoxia 2. Volatile anesthetics 3. Hypercarbia 4. Chronic hypertension
4. Chronic hypertension shifts the CBP autoregulatory curve to the right. The clinical significance of this observation is that CBP could decrease and cerebral ischemia could occur at a higher mean systemic arterial blood pressure in patients with chronic hypertension compared to normal patients. Chronic antihypertensive therapy to control systemic blood pressures within the normal range will restore normal CBP autoregulation.
Ketamine (Choose all of the questions that are correct). I. Decreases CBF 2. Augments the CÓ responsiveness of the cerebral vasculal. 3. Reduces CMR 4. Increases CBV
4. Increases CBV Ketamine is thought to increase CBF and, consequently, CBV and ICP by two mechanisms: (1) there may be a direct effect on cerebral vascular smooth muscle to cause vasodilation, and (2) there may be a "coupled" effect caused by an increase in CMR. There is some controversy regarding the effect of ketamine on CBPICMR coupling. Animal studies in vivo indicate that CMR and CBP are increased proportionally in structures of the limbic system. In contrast, there is evidence from one human study that although ketamine increased CBP (up to 62%), CMR remained unchanged. Cerebral CÓ responsiveness and autoregulation are not altered by ketamine
An 89-year-old man with a history of transient ischemic attacks is scheduled to undergo a carotid endarterectomy under general anesthesia. Which of the following would be appropriate in the anesthetic management of this patient?(Choose all of the questions that are correct). 1. Hyperventilation of the lungs to a Pacó of 30 mm Hg to reduce ICP 2. Injection of a local anesthetic around the carotid body to prevent bradycardia 3. Initiation of deliberate hypotension after induction of anesthesia to reduce bleeding. 4. Induction of anesthesia with sodium thiopental.
4. Induction of anesthesia with sodium thiopental General anesthesia can be induced safely in patients with carotid artery disease using intravenous anesthetics, such as thiopental, midazolam, propofol, or etomidate. Isoflurane, in conjunction with N20 or opioids, is a good choice for maintenance of anesthesia in these patients, because critical CBP is reduced during isoflurane, sevoflurane, or desflurane anesthesia, which may provide some cerebral protection (also see explanation to question 752). Arterial blood pressure and Pacó should be maintained in the normal ranges for each patient because the vasculature within ischemic regions of the brain have lost the ability to autoregulate CBP and respond to changes in Pacó• Marked reductions in arterial blood pressure may reduce CBF (especially via collateral channels) to ischemic brain tissue. Theoretically, if Pacó is increased from normal, cerebral blood vessels surrounding the region of ischemia that retain normal CÓ responsiveness will dilate, diverting rCBF away from the ischemic brain tissue (i.e., steal phenomenon). Conversely, if the Pacó is reduced from normal, the cerebral blood vessels surrounding the ischemic brain tissue will constrict, diverting rCBF to ischemic areas of the brain (inverse steal phenomenon or Robin Hood effect). Hyperventilating the lungs in an attempt to produce the inverse steal phenomenon is not recommended because the actual effect may be unpredictable. The carotid sinus (not carotid body) baroreceptor reflex can be blunted by intravenous injection of atropine or by local infiltration of the area of the carotid sinus with a local anesthetic.
Which of the following alarms would sound if the anesthesia breathing circuit became disconnected from the patient's endotracheal tube? (Choose all that apply 1. High pressure alarm 2. Continuing pressure alarm 3. Subatmospheric pressure alarm 4. Minimum ventilation pressure alarm
4. Minimum ventilation pressure alarm Alarm systems are integrated into anesthesia machines to aid and assist the anesthesia provider in making diagnoses of abnormal functions of the anesthesia machine. The location of the alarm and the alarm method vary with the particular model of machine. With regard to ventilator alarm systems, a high pressure alarm occurs whenever the circuit pressure exceeds approximately 65 em H20. The subatmospheric pressure alarm is triggered when the pressure in the breathing circuit decreases to less than 10 em H20 below atmospheric pressure. The continuing pressure alarm alerts the anesthesia provider that the airway pressure remains above 18 cm H20 for more than 10 seconds. A continuing pressure situation can occur with a blocked or closed pop-off valve, a malfunctioning ventilator pressure-relief valve, or obstruction of the scavenging system interface. The minimum ventilation pressure or "disconnect" alarm is triggered when the amplitude of the pressure wave during the inspiration cycle does not achieve a preselected minimum value. Disconnection of the patient's endotracheal tube from the anesthesia breathing circuit would trigger this alarm
The cricothyroid muscle : (Choose all that apply). 1. Is an extrinsic muscle of the larynx Anatomy, Regional Anesthesia, and Pain Management 349 2. Receives innervation from the recurrent laryngeal nerve 3. Receives innervation from the internal branch of the superior laryngeal nerve 4. Tenses the vocal cords
4. Tenses the vocal cords The cricothyroid muscle is the only intrinsic muscle of the larynx that tenses the vocal cords. It is innervated by the external branch of the superior laryngeal nerve of the vagus. All other intrinsic muscles of the larynx receive motor innervation from the recurrent laryngeal nerve
Calculate the ideal body weight for a woman who is 5ft 3in tall. (enter in kg & round to nearest whole number)
55kg 63in x.2.54= 160.02cm 160.02- 105= 55 W: Ht (cm) - 105 M: Ht (cm) - 100
A 42-year-old man is undergoing a thoracoscopy. During the procedure an 8-minute period of apneic oxygenation is required. If the patient's PaCO2 is 40 mm Hg, the expected PaCO2 at the end of the apneic period would be: ___________ MMHG
67 to 74 mm Hg The apneic oxygenation technique affords adequate oxygen delivery, but progressive respiratory acidosis limits the use of this technique to 10 - 20 minutes in most patients. Arterial PaCO2 rises 6 mm Hg in the first minute followed by a rise of 3 - 4 mm Hg during each subsequent minute. In this patient this will produce a 27 - 34 mm Hg increase, resulting in a PaCO2 of 67 to 74 mm Hg.
Leukoreduction, or the removal of leukocytes from the transfused blood products, reduces the incidence of all of the following EXCEPT A . Febrile transfusion reactions B . Cytomegalovirus (CMV) infection C. Rate of HLA alloimmunization D . Allergic urticarial transfusion reactions E . Bacterial transmission
7. ANSWER: D Leukoreduction is the process of removing white blood cells from blood products. Th is can be performed prior to storage of blood products or through the use of bedside leukoreduction fi lters at the time of transfusion. Bedside leukoreduction fi lters, however, are not as eff ective or uniform in leukoreduction compared to prestorage techniques. Furthermore, they are not capable of removing cytokines produced by leukocytes during storage that may incite nonhemolytic febrile transfusion reactions. U rticarial reactions are mild allergic transfusion reactions that occur in as many as 1% to 3% of all transfusions.
Basal metabolic oxygen consumption in a 20-kg patient is approximately:
95 ml/min Basal metabolic oxygen consumption can be estimated using the following formula: VÓ = 10 KG ^3/4
Basal metabolic oxygen consumption in a 20-kg patient is approximately: (Enter numerical answer in box below. Click 'Next' when completed.) _________ mL/min
95 ml/min Basal metabolic oxygen consumption can be estimated using the following formula: VÓ = 10kg(3/4)
The pressure gauge of a size "E" compressed-gas cylinder containing air shows a pressure of 900 psi. Approximately how long could air be delivered from this cylinder at the rate of 10 L/min? A. 10 minutes B. 20 minutes C. 30 minutes D. 40 minutes E. 50 minutes
A size "E" compressed-gas cylinder completely filled with air contains 625 L and would show a pressure gauge reading of 1800 psi. Therefore, a cylinder with a pressure gauge reading of 900 psi would be half-full, containing approximately 310 L of air. A half-full size "E" compressed-gas cylinder containing air could be used for approximately 30 minutes at a flow rate of 10 L/min
When selecting a needle for spinal anesthesia, which type is most likely to cause a postdural puncture headache? (A) 20-g Quincke (B) 22-g Whitacre (C) 22-g Sprotte (D) 22-g Quincke
A) 20-g Quincke Cutting needles (Quincke) are more likely to cause postdural puncture headaches as compared to pencil point needles. Larger gauge needles are also more likely to cause postdural puncture headaches.
A patient with a history of reflux and diabetes mellitus is scheduled for a bowel obstruction. Which of the following fasting guidelines apply? (A) NPO for 8 hours (B) Clear fluids up to 2 hours (C) Light meal up to 6 hours (D) NPO for 4 hours
A) NPO for 8 hours The patient's comorbidities and surgery are associated with increased risk for delayed gastric emptying and aspiration. Fasting guidelines remain conservative for patients at increased risk for aspiration. Relaxed fasting guidelines including a light meal or clear liquids apply only to patients not at risk for delayed gastric emptying.
What is the underlying pathology of cor pulmonale? (A) Pulmonary hypertension (B) Decreased pulmonary vascular resistance (C) Systemic hypertension (D) Orthostatic hypotension
A) Pulmonary hypertension The underlying pathology of cor pulmonale is pulmonary hypertension.
The superior laryngeal nerve innervates (pick 2) A- cricothyroid muscles B- Underside of the epiglottis. C- Trachea. D- Posterior 1/3 of the tongue.
A,B cricothyroid muscles, Underside of the epiglottis. Whenever you think about innovation of the airways, 4 nerves should come to mind. 1. Recurrent Laryngeal n 2. Superior laryngeal n 3. Glossopharyngeal n 4. Trigeminal n
During hip replacement surgery, cardiopulmonary changes associated with the application of acrylic bone cement include: (Select 3) A- hypotension secondary to cement monomer absorption B-hypoxemia secondary to air embolization C-hypoxemia secondary to fat embolization D-hypocarbia E-decreased pulmonary artery pressure F-increased end-tidal carbon dioxide
A,B, C -hypotension secondary to cement monomer absorption, hypoxemia secondary to air embolization, hypoxemia secondary to fat embolization During hip replacement surgery, hypotension associated with the use of acrylic bone cement has been attributed to absorption of methyl methacrylate monomer, embolization of air and bone marrow, lysis of red cells and marrow and conversion of methyl methacrylate to methacrylic acid. Hypoxemia is common. Embolic events cause an increase in dead space with a reduction in ETCÓ with an increase in PaCÓ.
Signs of cardiac tamponade include: (Select 2) A- distended neck veins B- increased QRS voltage seen on ECG C- decreased central venous pressure D- bradycardia E- systemic vasoconstriction F- an increase in systolic blood pressure during inspiration
A,C distended neck veins, systemic vasoconstriction Cardiac tamponade is indicated by the presence of neck vein distention, hypotension, muffled heart sounds (Beck's triad) and a greater than 10 mm Hg decline in blood pressure during spontaneous inspiration (pulsus paradoxus). Tachycardia and systemic vasoconstriction are present to maintain blood pressure with the associated decreased stroke volume.
The cardiovascular effects of pancuronium are caused by: (Select 3) A-vagal blockade B-stimulation of cardiac muscarinic receptors C-ganglionic stimulation D-decreased catacholamine reuptake E-direct myocardial stimulation F-blockade of cardiac slow calcium channels G-central thalamic stimulation
A,C,D vagal blockade, ganglionic stimulation, decreased catecholamine reuptake The cardiovascular effects of pancuronium are caused by the combination of vagal blockade and sympathetic stimulation. The latter is due to a combination of ganglionic stimulation, catecholamine release and decreased catecholamine reuptake.
Which patient should receive a type and crossmatch instead of a type and screen prior to surgery? Select (3) three (A) A 48-year-old female scheduled or an endovascular stent of an aortic aneurysm (B) An obese 12-year-old male undergoing an emergency tonsillectomy. (C) A 22-year-old male with a history of multiple blood transfusions. (D) A pregnant Rh-positive patient with Rh- negative baby undergoing emergency surgery (E) An 80-year-old female scheduled a hip replacement with a positive type and screen
A,C,E Type and cross matches are often performed be ore the need to transfuse but only when the patient's antibody screen is positive or high risk for a positive screen (C), when the probability of transfusion is high (A and E), or when the patient is considered at risk for alloimmunization.
Physiologic derangements seen in the patient with scleroderma include: (Select 3): A-pulmonary hypertension B-esophageal dysmotility C-excessive oral secretions and salivation D-myocardial fibrosis E-hypotension F-spastic quadraparesis
A,D,E Scleroderma is an autoimmune disease with multi-organ involvement. It is characterized by excessive deposition of collagen and subsequent fibrosis of the skin and internal organs. Manifestations are most evident in the skin, but pulmonary, cardiac, vascular and renal involvement may also be present. Patients with scleroderma are frequently difficult intubations and are at high risk for aspiration. Systemic hypertension from renal disease is very common. Xerostomia and decreased lacrimation are a result of exocrine gland involvement.
The age group with the highest minimum alveolar concentration (MAC) of desflurane is: A-2 - 3 months B-1 - 2 years C-25 - 30 years D-greater than 75 years
A- 2 - 3 months The two-to-three-months-of-age group represents the highest MAC requirement. MAC subsequently decreases with advancing age.
When compared to the apex of the lungs, which of the following are higher at the bases (Se.lect 2). A- Blood Flow B- PaÓ C- PaCÓ D- V/Q ratio
A- Blood Flow C- PaCÓ
DOPA decarboxylase facilitates the conversion of: A- DOPA to dopamine B- DOPA to tyrosine C- Dopamine to DOPA D- tyrosine to DOPA
A- DOPA to dopamine 1st Tyrosine to DOPA (Tyrosine hydroxylase) 2nd DOPA to dopamine (DOPA decarboxylase) 3rd Dopamine to NE (Dopamine beta hydroxylase) 4th NE to Epi (Phentolamine, N-methyltransferase)
The Bourbon pressure gauge can be used to calculate the cylinder volume for (Select 2 ). A- Nitrogen B- Helium C- Nitrous oxide D- Carbon Dioxide
A- Nitrogen B= Helium Both exist as a liquid.
The perception of an ordinarily non-noxious stimulus as pain is referred to as: A- allodynia B- anesthesia dolorosa C- dysesthesia D- hyperalgesia
A- allodynia Allodynia is the perception of non-noxious stimuli as pain. Dysesthesia is an unpleasant sensation without a stimulus. Hyperesthesia is an increased response to a mild stimulus. Anesthesia dolorosa is pain in an area that lacks sensation.
Enoxaparin: A-causes less platelet inhibition than heparin B- is easily reversed with protamine C- has a half-life that is 35% less than that of heparin D- effects are monitored using the INR
A- causes less platelet inhibition than heparin Low molecular weight heparins (LMWH), such as enoxaparin, have greater activity against factor Xa than thrombin. As a result, the INR is not a reliable monitoring tool. The LMWHs cause less platelet inhibition and are associated with a lesser incidence of heparin induced thrombocytopenia.
Droperidol: A- has antiarrhytmic activity B- causes shortening of the QT interval C- causes peripheral vasoconstriction D- is effective for blood pressure control in patients with pheochromocytoma
A- has antiarrhytmic activity Droperidol has mild alpha-blocking activity and causes vasodilation and has antiarrhythmic properties with prolongation of the QT interval. As a result of the prolongation of the QT interval, droperidol has been associated with torsades de pointes and should not be given to patients with QT intervals measuring more than 440 ms. Patients with pheochromocytoma should not receive droperidol because it can induce catecholamine release.
Pulmonary changes associated with Duchenne's muscular dystrophy include: A-a restrictive ventilatory defect B-an obstructive ventilatory defect C-decreased pulmonary artery pressures D- increased residual volume
A- restrictive ventilatory defect The combination of marked kyphoscoliosis and degeneration of the respiratory muscles produces a severe restrictive ventilatory defect in patients with Duchenne's muscular dystrophy. Pulmonary hypertension is also commonly seen.
Correct statements concerning the use of benzodiazepines in the elderly include: A- volume of distribution is increased B- reduced pharmacodynamic sensitivity is observed C- the elimination half-life of diazepam, but not midazolam, is increased D- all of the above
A- volume of distribution is increased Aging increases the volume of distribution for all benzodiazepines, effectively prolonging their elimination half-lives. Enhanced pharmacodynamic sensitivity is also observed. The elimination half-lives of both diazepam and midazolam are increased.
The half-life of morphine is prolonged in neonates (6 to 9 hours). The elimination half-life decreases to adult values by what age? A-4 to 6 months B-8 to 9 months C-11 to 12 months D-16 to 18 months
A-4 to 6 months Morphine is metabolized by uridine 5′‐diphosphate glucuronosyltransferase (UGT) to morphine‐3‐glucuronide (M3G) and morphine‐6‐glucuronide (M6G). The clearance and elimination of morphine is age-dependent. The clearance of morphine is reduced during the neonatal period and increases with increasing age but there is significant inter-individual variability. Most studies suggest total body morphine clearance is 80% that of adult values by 6 months of age.
Portal hypertension is defined as sustained portal vein pressure greater than: A-5 mm Hg above hepatic vein pressure B-10 mm Hg above hepatic vein pressure C-15 mm Hg above hepatic vein pressure D-20 mm Hg above hepatic vein pressure
A-5 mm Hg above hepatic vein pressure Portal hypertension is defined as a sustained portal vein pressure of 5 mm Hg or greater above hepatic vein pressure. This leads to the formation of portal-systemic collateral venous channels.
A 34-year-old otherwise healthy woman presents for resection of an occipital glioma in the seated position. She takes no medications. Her preoperative INR is 1.5. What is the likelihood that the transfusion of 2 units of fresh frozen plasma (FFP) would normalize her INR? A-< 5% B-25% C-50% D-75% E->90%
A-< 5% Abdel-Wahab prospectively audited all fresh frozen plasma (FFP) transfusions for an INR of 1.1-1.85 at Massachusetts General Hospital over 13 months (324 transfusions had the necessary follow up data). Transfusion of FFP resulted in normalization of only PT-INR values in 0.8% of patients and decreased the INR halfway to normalization in 15% of patients. Interestingly, there was no significant relationship between pretransfusion INR and likelihood of achieving 50 percent correction of the INR after FFP transfusion). There was no dose-response effect, and increasing amounts of FFP did not appear to result in larger decrements in INR. Median decrease in INR was 0.07.
The most severe transfusion reactions are due to: A-ABO incompatibility B-Rh incompatibility C-febrile reactions D-non-ABO hemolytic reactions
A-ABO incompatibility The most severe transfusion reactions are due to ABO incompatibility. Naturally acquired antibodies can react against the transfused antigens, activate complement and result in intravascular hemolysis.
A 57-year-old woman with a history of hypertension, type 2 diabetes mellitus, obesity, severe asthma, and coronary artery disease presents for elective laparoscopic cholecystectomy. The patient arrives the morning of surgery and informs the anesthesiologist that she takes a daily metoprolol but did not take it this morning. Which of the following beta-blockers would be MOST appropriate to administer to the patient prior to surgery? A-Acebutolol B-Nadolol C-Pindolol D-Timolol
A-Acebutolol Patients with a history of known coronary artery disease who are taking a daily beta-blocker should continue the beta-blocker the day of surgery. Given that the patient has a history of severe asthma, it is most appropriate to administer a beta-1 selective beta-blocker. Of the above choices, only acebutolol is a beta-1 selective beta-blocker.
A previously healthy 32-year-old G1P0 patient at 39 weeks gestation is rushed to the operating room for cesarean delivery after fetal heart rate tracings display prolonged late decelerations. The patient is induced with propofol, intubated by rapid sequence with succinylcholine, and maintained with 1.8% isoflurane in 100% oxygen. The fetus is delivered safely, but the patient's blood pressure is noted to be 85/40 mmHg throughout the procedure, down from a baseline of 115/60 mmHg; it responds appropriately and transiently to ephedrine and phenylephrine boluses. The heart rate range is 70-90 bpm, SpO2 is 100% and blood loss is estimated at 900 mL. What is the most likely etiology of hypotension? A-Anesthetic overdose B-Amniotic fluid embolism C-Chorioamnionitis D-Postpartum hemorrhage
A-Anesthetic overdose Pregnant patients have decreased MAC requirements of 25-40% compared to non-pregnant women. Isoflurane at 1.8% would be a high dose even in non-pregnant patients (roughly 1.5 MAC), but adjusting for pregnancy it would be closer to 1.7- 2.0 MAC, or approximately the level at which the sympathetic system stops responding to stimuli (MAC-bar). Such hypotension should respond well to pharmacologic sympathetic stimulation with ephedrine or phenylephrine. In contrast, amniotic fluid embolism rapidly deteriorates to total cardiovascular collapse. The blood loss is typical for a cesarean delivery and since the heart rate is not increased, postpartum hemorrhage is less likely. Chorioamnionitis would likely have been present prior to induction of anesthesia, and associated with fever, tachycardia, and possibly hypotension prior to arrival in the operating room.
A previously healthy 32-year-old G1P0 patient at 39 weeks gestation is rushed to the operating room for cesarean delivery after fetal heart rate tracings display prolonged late decelerations. The patient is induced with propofol, intubated by rapid sequence with succinylcholine, and maintained with 1.8% isoflurane in 100% oxygen. The fetus is delivered safely, but the patient's blood pressure is noted to be 85/40 mmHg throughout the procedure, down from a baseline of 115/60 mmHg; it responds appropriately and transiently to ephedrine and phenylephrine boluses. The heart rate range is 70-90 bpm, SpÓ is 100% and blood loss is estimated at 900 mL. What is the most likely etiology of hypotension? A-Anesthetic overdose B-Amniotic fluid embolism C-Chorioamnionitis D-Postpartum hemorrhage
A-Anesthetic overdose. Pregnant patients have decreased MAC requirements of 25-40% compared to non-pregnant women. Isoflurane at 1.8% would be a high dose even in non-pregnant patients (roughly 1.5 MAC), but adjusting for pregnancy it would be closer to 1.7- 2.0 MAC, or approximately the level at which the sympathetic system stops responding to stimuli (MAC-bar). Such hypotension should respond well to pharmacologic sympathetic stimulation with ephedrine or phenylephrine. In contrast, amniotic fluid embolism rapidly deteriorates to total cardiovascular collapse. The blood loss is typical for a cesarean delivery and since the heart rate is not increased, postpartum hemorrhage is less likely. Chorioamnionitis would likely have been present prior to induction of anesthesia, and associated with fever, tachycardia, and possibly hypotension prior to arrival in the operating room.
A 63-year-old man with a history of type 2 diabetes mellitus and chronic renal insufficiency is scheduled to undergo a CT scan with contrast. Which of the following is MOST likely reduce the likelihood of contrast-induced nephropathy in this patient? A-Bicarbonate infusion B-Insulin C-Furosemide D-Mannitol
A-Bicarbonate infusion The most important step in the prevention of contrast nephropathy is limiting risk factors such as hypovolemia and high doses of contrast dye. Randomized trials have concluded that mannitol and furosemide increase the risk of contrast-induced nephropathy and thus have no role in its prevention. Sodium bicarbonate is commonly used to prevent contrast nephropathy. The theoretical benefit of sodium bicarbonate is decreased acidification of the urine and renal medullary environment, which may reduce free radical injury. The cornerstone of prevention of contrast nephropathy is appropriate risk stratification, intravenous hydration with normal saline or sodium bicarbonate, appropriate withholding of nephrotoxic medications, use of low or iso-osmolar contrast media, and various intraprocedural methods for iodinated contrast dose reduction.
A 57-year-old man with ESRD develops progressive bradycardia with peaked T-waves following reperfusion of the renal allograft during a kidney transplant. Which of the following is the MOST appropriate initial treatment? A-Calcium chloride 500-1000 mg IV B-Glucose 25-50g/Insulin 5-10 U IV C-Hyperventilation to PaCO2 30 mmHg D-Sodium bicarbonate 8.4 % 50 ml IV
A-Calcium chloride 500-1000 mg IV This patient has ECG changes that suggest symptomatic hyperkalemia. All the options listed would effectively lower serum potassium. Glucose/Insulin, hyperventilation, and bicarbonate all function by shifting potassium from the extracellular space into the intracellular space. Unfortunately, each of these interventions takes time (5-10 minute minimum) to be effective. Calcium is a physiologic antagonist and can temporarily stabilize the myocardium. Calcium is effective almost immediately and thus is the initial treatment of choice in this patient.
Which of the following is MOST correct regarding red blood cells in the capillary of an extremity when compared to red blood cells in the pulmonary veins? A-Carbonic acid-bicarbonate buffer equation shifts right B-Hemoglobin binds CÓ less avidly C-Levels of 2,3-DPG are decreased D-P50 is decreased
A-Carbonic acid-bicarbonate buffer equation shifts right RBCs possess many adaptations to facilitate maximal unloading of oxygen at peripheral tissues with maximal transport of CÓ back to the lungs. The Bohr effect facilitates the rightward shift of the oxyhemoglobin dissociation curve (thereby increasing the P50 of hemoglobin), where oxygen is more easily unloaded with increased levels of 2,3-DPG. Meanwhile, the Haldane effect refers to the increased affinity for CÓ that deoxyhemoglobin has when compared with oxyhemoglobin. This optimizes transport of CÓ from the periphery (deoxygenated hemoglobin picks up a maximum amount of CÓ at peripheral tissues), and also optimizes the amount of CÓ unloading that occurs in the lungs (oxygenated hemoglobin will have a lower affinity for CÓ and will therefore unload CÓ in the lungs). This change in affinity is made possible via a rightward shift in the carbonic acid-bicarbonate buffer equation such that H+ is produced, thus increasing the affinity of CÓ for hemoglobin.
A 60-year-old man is emergently brought to the OR for right a hemicraniectomy. The patient had a right middle cerebral artery stroke two days ago and now has clinical uncal herniation syndrome (coma with blown right pupil). What are the anesthetic considerations for this procedure? A-Control cerebral edema; avoid hypotension leading to further hypoperfusion injury; avoid cerebral vasodilatation with halogenated anesthetics. B-Minimizing delay; maintain hypovolemia to avoid increased cerebral edema; cerebral vasodilatation from propofol. C-Control cerebral edema; head down position to optimize cerebral perfusion; cerebral vasodilatation from inhalational agents. D-Avoid hypertension to minimize cerebral edema; hyperventilation to reduce cerebral blood volume selfstudyplus.
A-Control cerebral edema; avoid hypotension leading to further hypoperfusion injury; avoid cerebral vasodilatation with halogenated anesthetics. There is high-level evidence for the efficacy of hemicraniectomy in reducing morbidity and mortality from malignant middle cerebral artery strokes. In this setting, "malignant" refers to life-threatening cerebral edema. Patients have unilateral cerebral edema, may be developing herniation, and may have increased ICP. Intravenous anesthesia with maintenance of cerebral perfusion pressure (i.e., hypertension and euvolemia) is a preferred approach similar to any craniotomy for acute space occupying intracranial lesion. Hyperventilation and hyperosmotic therapy, with mannitol or hypertonic saline, are used concomitantly. The herniation syndrome makes the procedure in this patient an emergency. A pre-emptive hemicraniectomy, prior to clinical neurologic deterioration, would be handled as an urgent but not emergent case.
You are called to the NICU to perform an anesthetic on a 3.5 kg neonate with congenital diaphragmatic hernia. The patient is intubated with conventional mechanical ventilation. The most recent arterial blood gas reveals a pH 7.38, PaCO2 45 mmHg, PaO2 89 mmHg, HCO3 29 mEq/L, SaO2 of 97% on an FiO2 of 0.6. Peak airway pressures are 32 cmH2O with 5 cmH2O PEEP. Expiratory tidal volume is 45 ml. Which of the following is the MOST appropriate ventilatory management for this patient? A-Decrease peak airway pressure to 25 cmH2O B-Decrease FiO2 to 50% C-Increase FiO2 to 90% D-Increase PEEP to 7 cmH2O
A-Decrease peak airway pressure to 25 cmH2O Due to the concern of aggressive ventilation on both the short-term survival as well as long-term outcomes of congenital diaphragmatic hernia, ventilatory strategies that employ small tidal volumes with permissive hypercapnia have gained widespread acceptance. Boloker, et al. suggested preservation of spontaneous ventilation, acceptance of a pre-ductal oxygen saturation of 90-95% with >80% tolerated if the infant appears comfortable, permissive hypercapnia of 60-65 mmHg, and peak inspiratory pressures < 25 cm H20
You are called to the NICU to perform an anesthetic on a 3.5 kg neonate with congenital diaphragmatic hernia. The patient is intubated with conventional mechanical ventilation. The most recent arterial blood gas reveals a pH 7.38, PaCÓ 45 mmHg, PaÓ 89 mmHg, HCǑ 29 mEq/L, SaÓ of 97% on an FiÓ of 0.6. Peak airway pressures are 32 cmH2O with 5 cmH2O PEEP. Expiratory tidal volume is 45 ml. Which of the following is the MOST appropriate ventilatory management for this patient? A-Decrease peak airway pressure to 25 cmH2O B-Decrease FiÓ to 50% C-Increase FiÓ to 90% D-Increase PEEP to 7 cmH2O
A-Decrease peak airway pressure to 25 cmH2O Due to the concern of aggressive ventilation on both the short-term survival as well as long-term outcomes of congenital diaphragmatic hernia, ventilatory strategies that employ small tidal volumes with permissive hypercapnia have gained widespread acceptance. Boloker, et al. suggested preservation of spontaneous ventilation, acceptance of a pre-ductal oxygen saturation of 90-95% with >80% tolerated if the infant appears comfortable, permissive hypercapnia of 60-65 mmHg, and peak inspiratory pressures < 25 cm H20.
A 4-week-old infant presents with tachycardia and tachypnea and is refusing to take anything by mouth. Chest x-ray reveals congenital emphysema on the left. What would be the most likely findings on physical exam on the affected side? A-Decreased breath sounds, hyper-inflation, hyper-resonance. B-Decreased breath sounds, hyper-inflation, hypo-resonance. C-Increased breath sounds, hyper-inflation, hyper-resonance. D-Increased breath sounds, hyper-inflation, hypo-resonance.
A-Decreased breath sounds, hyper-inflation, hyper-resonance. Congenital lobar emphysema is a developmental anomaly of the lung that is characterized by hyperinflation of one or more of the pulmonary lobes. The left lung is more commonly involved and specifically the left upper lobe is the most commonly affected. Infants typically have tachypnea and increased work of breathing, and may have cyanosis. Recurrent pneumonia or poor feeding with failure to thrive are less frequent presentations that may occur in milder forms. Physical examination reveals decreased breath sounds and hyperresonance to percussion. A chest x-ray will reveal hyper-inflation.
A 3-month-old full term boy presents for right inguinal hernia repair. He experiences an intravascular injection during the administration of a caudal the test dose. Atropine was administered 5 minutes prior to the test dose. What is the EARLIEST clinical marker of this intravascular injection of epinephrine? A-HR increase greater than 10 bpm B-HR increase greater than 20 bpm C-SBP increase greater than 25 mmHg D-ST segment elevation greater than 25%
A-HR increase greater than 10 bpm The earliest sign of intravascular injection is T wave elevation greater than 25% (not ST segment elevation). Another very sensitive marker of intravascular injection is an elevation in HR of 10 or more bpm. Unlike adults, children are usually under anesthesia during the test dose and the sensitivity of epinephrine is reduced (especially when halothane was used) if the standard HR response of 20 bpm is expected. The administration of an anticholinergic and reducing the HR response to 10 bpm will increase the sensitivity of the test dose. In fact some evidence suggests that if atropine or glycopyrrolate is given prior to the test dose and a HR of 10 bpm is utilized, the sensitivity of 0.5 mcg/kg is 100%.
A 70-year-old man suffers a ruptured descending aortic aneurysm and presents for emergent open repair. Which of the following effects is MOST important after aortic cross-clamping in determining anticipated intraoperative hemodynamic changes? A-Level of the cross clamp B-Myocardial function C-Presence of aortoiliac occlusive disease D-Volume status
A-Level of the cross clamp. While all of the above answers have an effect on the patient's hemodynamics during the time of aortic cross-clamping, the major factor that determines the consequences of aortic cross clamping is the level of the clamp on the aorta. The majority of abdominal aortic aneurysmectomies are performed with an infrarenal cross-clamp, which produces the least effect hemodynamically. Juxtarenal, suprarenal and supraceliac clamps produce increasing hemodynamic effects, in respective order. There is arterial hypertension ABOVE the level of the clamp and hypotension BELOW the level of the clamp. A patient with aortoiliac occlusive disease lives in a chronically "clamped" state and has likely developed significant collateralization due to the nature of vascular disease. Those patients have the least hemodynamic change related to cross clamping. Volume status is very important in a patient with a ruptured aneurysm, but during the cross clamp, central venous pressure and preload are augmented usually due to blood volume redistribution from the splanchnic vascular bed. In addition, baseline myocardial function is vitally important. In patients with preserved myocardial function, aortic cross clamping is usually well tolerated, despite the increased ventricular afterload due to the clamp. In patients who have coronary artery disease, reduced coronary blood flow, aortic regurgitation or reduced myocardial reserve, placement of the aortic cross clamp may be met with decompensation, dilation and failure of the left ventricle, with resultant acute mitral regurgitation and pulmonary edema.
A 49-year-old man is resuscitated following an opioid-induced respiratory arrest followed by cardiac arrest in PACU. He has return of spontaneous circulation after CPR/ACLS and is intubated for airway protection. He has not awakened. What is the MOST appropriate next step in his care? A-Naloxone followed by therapeutic hypothermia B-Neurology consultation C-Therapeutic hypothermia D-Transfer to ICU for supportive care
A-Naloxone followed by therapeutic hypothermia The patient has persistent coma following an anoxic brain insult. Because you suspect that it may be opioid-induced, naloxone therapy is reasonable. If he does not become responsive to the point of following commands with naloxone therapy, therapeutic hypothermia should be initiated immediately. Cold IV fluids are the most rapid method to induce hypothermia. Target temperature is 32-34°C for 24
A 65-year-old man with a history of coronary artery disease and previous CABG has a 6 cm abdominal aortic aneurysm (AAA). He presents to the OR for elective open repair of his AAA. Which of the following medications will be MOST likely to improve his myocardial function during the aortic cross-clamping? A-Nitroprusside B-Phenoxybenzamine C-Epinephrine D-Norepinephrine
A-Nitroprusside Principles of hemodynamic management during the period of aortic cross-clamping in patients with decreased myocardial reserve include reduction in afterload with arteriolar dilators such as nitroprusside and reduction in preload with venodilators such as nitroglycerin. Phenoxybenzamine is longer-acting, orally administered alpha-blocker which is often used in treatment of hypertension in patients with pheochromocytoma. It is not appropriate for use in AAA repair. Care should be taken with reduction in blood pressure in order prevent worsening of visceral ischemia distal to the aortic occlusion. Vasoconstrictors such as norepinephrine and epinephrine may be useful with removal of the aortic cross-clamp in low vascular resistance states. Epinephrine is not usually required as it often increases heart rate and myocardial oxygen consumption while increasing myocardial contractility. Other helpful management options after the cross clamp is removed include volume administration, treatment for hyperkalemia, acidosis and arrhythmias.
A patient with an acute subdural hematoma is brought to the operating room for emergent clot evacuation. He is intubated and has a large, non-reactive right pupil suggestive of an uncal herniation syndrome. Which of the following anesthetic approaches is MOST appropriate? A-Propofol TIVA with vasopressors to maintain CPP B-Isoflurane titrated to burst suppression C-Pentobarbital load followed by continuous infusion D-Desflurane plus nitrous oxide
A-Propofol TIVA with vasopressors to maintain CPP Propofol has the best pharmacologic characteristics in this setting. It lowers cerebral metabolic rate, causes a reduction in cerebral vessel caliber and cerebral blood volume, and can readily be titrated to burst suppression if desired. Sevoflurane is the best of the three halogenated inhalational agents but still causes some cerebral vasodilatation. Keep in mind that this patient has a herniation syndrome that will be fatal if not promptly reversed. The overall management involves rapid delivery to the surgical "˜cure' (no delays), hyperventilation, anesthesia to avoid stimulation induced spikes in ICP (propofol-remifentanil for example), hyperosmotic therapy (mannitol 1gm/kg), and maintenance of cerebral perfusion pressure. A CPP target is just a guess since the patient does not have an ICP monitor and there is no currently available point-of-care cerebral blood flow monitor. Assuming an elevated ICP of 30mmHg, as a guesstimate in this patient, the target MAP would be 90 to provide a CPP of 60.
A 110 kg man presents for right upper lobectomy via a thoracoscopic approach for squamous cell carcinoma located in the right upper lobe. His preoperative exam is significant for micrognathia. Which of the following characteristics of a single lumen ETT used with a bronchial blocker instead of a double lumen endobronchial tube provides the GREATEST advantage in this patient? A-Relative ease of intubation with single lumen ETT B-Superior and reliable lung isolation C-Use of CPAP for operative lung D-Decreased cost
A-Relative ease of intubation with single lumen ETT Various techniques exist for lung isolation and one lung ventilation (OLV) during thoracoscopic lung resection. Either a double lumen endobronchial tube (DLT) or a single lumen ETT with a bronchial blocker can be successfully used to achieve OLV. Although better lung isolation is typically achieved with a DLT, single lumen ETT's with bronchial blockers do offer some advantages. Because the airway is secured with a single lumen tube, the actual act of intubation is typically easier (note, though, that it is not necessarily easier to achieve correct positioning of the bronchial blocker for lung isolation than it is for positioning of the DLT within the tracheobronchial tree, (Bauer et al. 2001).). Additionally, single lumen ETT's with bronchial blockers allow the isolation of individual lung segments, and should mechanical ventilation need to be continued post-operatively, tube exchange is not required. Bronchial blockers, however, are associated with a greater expense. It is not possible to apply CPAP or suction the operative lung through a bronchial blocker.
Regarding cardiopulmonary bypass, if pump outflow is occluded, excessive pressure can build proximal to the occlusion if which kind of pump is used? A-Roller pump B-Centrifugal pump C-Neither roller nor centrifugal pump D-Either roller or centrifugal pump
A-Roller pump During cardiopulmonary bypass, a mechanical pump is required to circulate blood through the circuit and then back to the patient. In general, 2 types of pumps are utilized for this purpose: roller pumps and centrifugal pumps. Flow of a roller pump is predictable and depends on the revolutions per minute of the pump. Although retrograde flow is not possible, if there is outflow occlusion to the pump, excessive pressure can build, causing the tubing to rupture or the tubing connections to separate. Of course, there are safety checks in place to prevent this from occurring.
A 30-year-old man with acromegaly undergoes the transsphenoidal resection of a pituitary adenoma. On postoperative day one, the patient develops a brisk diuresis. Which of the following laboratory measurements MOST supports the diagnosis of diabetes insipidus? A-Serum sodium 145 meq/L B-Serum sodium 135 meq/L C-Urine osmolarity of 300 mOsm/L D-Urine osmolarity of 450 mOsm/L
A-Serum sodium 145 meq/L Diabetes insipidus (DI) may be pituitary (central) or nephrogenic. Pituitary DI is characterized by a relative or absolute deficiency of antidiuretic hormone (ADH). Nephrogenic DI is characterized by kidneys that do not respond normally to ADH. In the context of pituitary surgery, pituitary DI is much more common. The relative or absolute deficiency of ADH results in the failure of the distal and collecting tubules to absorb water. This results in dilute urine and, most commonly, a rising serum sodium.
When do pharmacokinetic interactions occur? a- When one drug alters the absorption/distribution/metabolism/ excretion of another. b- Before a drug is administered or absorbed systematically. c- When one drug alters the sensitivity of a target receptor or tissue to the effects of a second drug. d- none of the above.
A-When one drug alters the absorption/distribution/metabolism/ excretion of another. [Pharmacokinetic interactions occur when more than one drug is administered and the interactions are dictated by the effects of one drug on the absorption, distribution, metabolism, and elimination of another drug. ]
Pulmonary changes associated with Duchenne's muscular dystrophy include: A-a restrictive ventilatory defect B-an obstructive ventilatory defect C-decreased pulmonary artery pressures D-ncreased residual volume
A-a restrictive ventilatory defect The combination of marked kyphoscoliosis and degeneration of the respiratory muscles produces a severe restrictive ventilatory defect in patients with Duchenne's muscular dystrophy. Pulmonary hypertension is also commonly seen.
Carbonic anhydrase inhibitors are used in the treatment of: A-acute glaucoma B-renal tubular acidosis C-diarrhea induced acidosis D-acidosis resulting from hypoventilation
A-acute glaucoma Carbonic anhydrase inhibitors decrease the ability of the kidneys to reabsorb bicarbonate, resulting a hyperchloremic acidosis. As a result, carbonic anhydrase inhibitors would be avoided in patients with acidosis, especially a normal-anionic-gap acidosis. Because bicarbonate is filtered by the ciliary process in the formation of aqueous humor, carbonic anhydrase inhibitors reduce the formation of aqueous humor and can be used to decrease intraocular pressure.
The perception of an ordinarily non-noxious stimulus as pain is referred to as: A-allodynia B-anesthesia dolorosa C-dysesthesia D-hyperalgesia
A-allodynia Allodynia is the perception of non-noxious stimuli as pain. Dysesthesia is an unpleasant sensation without a stimulus. Hyperesthesia is an increased response to a mild stimulus. Anesthesia dolorosa is pain in an area that lacks sensation.
The purpose of the ductus venosus in fetal circulation is to: A-allow umbilical vein blood to bypass the liver B-allow umbilical artery blood to bypass the liver C-bypass the pulmonary circulation D-divert portal vein blood to the placenta
A-allow umbilical vein blood to bypass the liver Up to 50% of the umbilical vein blood can pass directly into the inferior vena cava, bypassing the liver, through the ductus venosus. The remainder mixes with blood from the portal vein and passes through the liver prior to returning to the heart.
Congenital heart diseases associate with right-to-left shunting include: (Select 3) A- atricuspid atresia B- hypoplastic left heart syndrome C- aortopulmonary window D- patent ductus arteriosus E- tetralogy of Fallot F- subvalvular aortic stenosis G- ventricular septal defects H- atrial septal defects
A-atricuspid atresia, B-hypoplastic left heart syndrome, E-tetralogy of Fallot Right-to-left shunting (cyanotic) heart disease is associated with: Tetrology of Fallot, pulmonary atresia, triscupid atresia, transposition of the great vessels, truncus arteriosus, single ventricle, double-outlet ventricle, total anomalous pulmonary venous return and hypoplastic left heart. With tricuspid atresia, blood can flow out of the right atrium only via a patent foramen ovale (PFO). A PDA or VSD is necessary for the blood to flow from the left ventricle to the pulmonary circulation.
Neuroleptic malignant syndrome: A-can be precipitated with the use of metoclopramide B-carries a mortality of over 80% C-can be treated with physostigmine administration D-can be diagnosed with muscle biopsy
A-can be precipitated with the use of metoclopramide. Neuroleptic malignant syndrome is a rare complication of antipsychotic therapy. Meperidine and metoclopramide can also precipitate the disorder which appears to be secondary to dopamine blockade in the basal ganglia. The disease has many characteristics in common with MH including increased temperature, metabolic derangement and hyperthermia. The mortality is 20 - 30%. Treatment with dantrolene and dopamine agonist, bromocripitine, appears effective.
Examples of Type IV hypersensitivity reactions include: A-contact dermatitis B-hemolytic transfusion reactions C-anaphylaxis D-angioedema
A-contact dermatitis Type IV hypersensitivity reactions are delayed and cell-mediated. Examples of Type IV reactions include contact dermatitis, tuberculin-type hypersensitivity and chronic hypersensitivity pneumonitis.
Key elements in the AANA's definition of wellness include: (Select 3) A-effective adaptation B-resilience C-professionalism D-competence E-coping mechanisms F-compassion G-fortitude H-perseverance
A-effective adaptation, B-resilience, E-coping mechanisms The AANA defines wellness as a positive state of the mind, body, and spirit reflecting a balance of effective adaptation, resilience, and coping mechanisms in personal and professional environments that enhance quality of life.
Anesthetic implications of multiple sclerosis include: A-exacerbation induced by spinal anesthesia B-exacerbation induced by epidural anesthesia C-exacerbation of symptoms secondary to hypothermia D-the presence of significant peripheral neuropathy causing severe hyperkalemia after succinylcholine administration.
A-exacerbation induced by spinal anesthesia Spinal anesthesia has been reported to cause exacerbation of the disease. Epidural and other regional techniques appear to have no adverse effect, especially in obstetrics; however a lower concentration of local anesthetic should be used. Demyelinated nerve fibers are extremely sensitive to hyperthermia, but conduction is usually improved by mild hypothermia.
Anesthetic implications of multiple sclerosis include: A- exacerbation induced by spinal anesthesia B- exacerbation induced by epidural anesthesia C- exacerbation of symptoms secondary to hypothermia D- the presence of significant peripheral neuropathy causing severe hyperkalemia after succinylcholine administration.
A-exacerbation induced by spinal anesthesia Spinal anesthesia has been reported to cause exacerbation of the disease. Epidural and other regional techniques appear to have no adverse effect, especially in obstetrics; however a lower concentration of local anesthetic should be used. Demyelinated nerve fibers are extremely sensitive to hyperthermia, but conduction is usually improved by mild hypothermia.
Airway obstruction caused by the tongue falling posteriorly against the wall of the pharynx is secondary to relaxation of the: A-genioglossus muscle B-longitudinal muscle of the tongue C-palatoglossus muscle D-styloglossus muscle
A-genioglossus muscle The genioglossus muscle allows the tongue to be protruded and kept away from the posterior pharynx. It is innervated by the hypoglossal nerve. The palatoglossus muscle elevates the tongue and depresses the soft palate. The styloglossus muscle elevates and retracts the tongue. The superior longitudinal muscle of the tongue is an intrinsic muscle of the tongue that elevates the tip.
Forms of mechanical ventilation that produce tidal volumes at or below anatomic dead space include: (Select 2) A-high-frequency oscillation B-inverse I:E ratio ventilation C-airway pressure release ventilation D-differential lung ventilation E-high-frequency positive-pressure ventilation F-pressure support ventilation
A-high-frequency oscillation, E-high-frequency positive-pressure ventilation High-frequency oscillation (HFO) creates a to-and-fro gas movement in the airway at rates of 180 - 3000 times/min. High frequency positive-pressure ventilation is delivered at a rate of 60 - 120 breaths/min. Tidal volume is at or below anatomic dead space. High-frequency ventilation techniques may be useful in cases of bronchopleural and tracheoesophageal fistulas.
During hip replacement surgery, cardiopulmonary changes associated with the application of acrylic bone cement include: (Select 3) A-hypotension secondary to cement monomer absorption B-hypoxemia secondary to air embolization C-hypoxemia secondary to fat embolization D-hypocarbia E-decreased pulmonary artery pressure F-increased end-tidal carbon dioxide
A-hypotension secondary to cement monomer absorption B-hypoxemia secondary to air embolization C-hypoxemia secondary to fat embolization During hip replacement surgery, hypotension associated with the use of acrylic bone cement has been attributed to absorption of methyl methacrylate monomer, embolization of air and bone marrow, lysis of red cells and marrow and conversion of methyl methacrylate to methacrylic acid. Hypoxemia is common. Embolic events cause an increase in dead space with a reduction in ETCÓ with an increase in PaCÓ.
Deleterious effects of hypothermia include: (Select 2) A-impaired renal function B-right shift of the hemoglobin-oxygen saturation curve C-irreversible platelet dysfunction D-increased incidence of wound infection E-increased postoperative protein anabolism
A-impaired renal function, B-increased incidence of wound infection Deleterious effects of hypothermia include: increased PVR left shift of the hemoglobin-oxygen saturation curve reversible platelet dysfunction postoperative protein catabolism altered mental status impaired renal function decreased drug metabolism poor wound healing increased incidence of infection cardiac arrhythmias
Absolute contraindications to the use of epidural anesthesia in the parturient include: (Select 2) A-inability of the patient to cooperate B-herniated lumbar disc C-multiple sclerosis D-patient refusal E-history of previous cesarean section F-aortic regurgitation
A-inability of the patient to cooperate D-patient refusal Absolute contraindications to epidural anesthesia/analgesia in the parturient include infection over the injection site, coagulopathy, thrombocytopenia, marked hypovolemia, true local anesthetic allergy, patient refusal and inability of the patient to cooperate. Preexisting neurological disease and back disorders are relative contraindications. Patients with aortic regurgitation usually benefit from the reduction in afterload seen after neuraxial anesthesia.
In addition to providing analgesia, tramadol has been shown to: A-inhibit the reuptake of serotonin and norepinephrine. B-inhibit cholinesterase. C-significantly delay gastric emptying. D-cause comparable respiratory depression to morphine.
A-inhibit the reuptake of serotonin and norepinephrine. Tramadol is a synthetic opioid that also blocks neuronal reuptake of norepinephrine and serotonin. Tramadol is associated with significantly less respiratory depression and delay in gastric emptying as compared to other narcotics.
Electrolyte containing irrigation solutions are avoided during transurethral resection of the prostate because they: A-interfere with the use of the cautery B-can precipitate severe hyponatremia D-can cause hyperglycemia in diabetic patients E-are associated with elevated ammonia levels postoperatively
A-interfere with the use of the cautery Electrolyte containing solutions conduct electricity and interfere with cautery use during the resection of the prostate. Electrolyte solutions are commonly used in the postop period. Sorbitol solutions have been associated with hyperglycemia, especially in diabetic patients. Glycine solutions have been associated with elevated ammonia levels and transient postoperative visual syndrome. Sorbitol, glycine and distilled water have all been associated with TURP syndrome.
The elimination half-time of a drug: A-is inversely proportional to the clearance B-is inversely proportional to the volume of distribution C-is directly proportional to clearance D-is shortest in drugs that are rapidly redistributed
A-is inversely proportional to the clearance The elimination half-time of a drug is proportional to the volume of distribution and inversely proportional to the rate of clearance.
The potency of local anesthetics increases as the: A-lipid solubility increases B- pKa increases C-number of double bonds in the anesthetic molecule increases D-molecular weight decreases
A-lipid solubility increases Local anesthetic potency correlates directly with lipid solubility. In general, lipid solubility increases with an increase in the total number of carbon atoms in the molecule and by adding a halogen to the aromatic ring.
Highly specific preoperative screening tests have a: A-low incidence of false-positives results B-low incidence of false-negative results C-result that is specific for one pathologic process D--low sensitivity
A-low incidence of false-positives results The usefulness of a screening test depends on its sensitivity and specificity. Sensitive tests have a low rate of false-negative results, whereas specific tests have a low rate of false-positive results.
The most frequent manifestation of sickle cell disease is: A- pain B-splenic sequestration C- aplastic crisis D- right upper quadrant syndrome
A-pain The most frequent manifestation of sickle cell disease is pain. The pain is thought to be secondary to tissue ischemia and usually affects the back, chest, extremities and abdomen.
A decrease in pseudocholinesterase activity has been associated with the use of: (Select 3) A-pancuronium B-esmolol C-droperidol D-vecuronium E-metoclopramide F-magnesium sulfate G-dantrolene H-rocuronium
A-pancuronium, B-esmolol, E-metoclopramide The following drugs have been associated with a decrease in pseudocholinesterase activity: echothiophate, pyridostigmine, neostigmine, phenelzine, cyclophosphamide, metoclopramide, esmolol, pancuronium and oral contraceptives. Although both dantrolene and magnesium may alter the effects of neuromuscular blockers, neither causes inhibition of pseudocholinesterase.
A nonselective α-antagonist used in the preoperative preparation of a patient with pheochromocytoma is: A-phenoxybenzamine B-doxazosin C-propranolol D-terazosin
A-phenoxybenzamine Phenoxybenzamine is a nonselective α-antagonist used in the preoperative preparation of the patient with pheochromocytoma. Doxazosin and terazosin are selective α1-antagonists. Propranolol is a nonselective β-antagonist. In the preparation of patients with pheochromocytoma, α-blockade and intravascular volume replacement must precede β-blockade, so as to prevent the possibility of unopposed α-stimulation.
A nonselective α-antagonist used in the preoperative preparation of a patient with pheochromocytoma is: A- phenoxybenzamine B- doxazosin C- propranolol D-terazosin
A-phenoxybenzamine Phenoxybenzamine is a nonselective α-antagonist used in the preoperative preparation of the patient with pheochromocytoma. Doxazosin and terazosin are selective α1-antagonists. Propranolol is a nonselective β-antagonist. In the preparation of patients with pheochromocytoma, α-blockade and intravascular volume replacement must precede β-blockade, so as to prevent the possibility of unopposed α-stimulation.
Mortality after liposuction procedures most commonly is the result of: A-pulmonary embolism B-bowel perforation C-fat embolization D-reactions to anesthetic agents
A-pulmonary embolism The mortality rate from liposuction procedures is approximately 0.02%. The most common cause of mortality is pulmonary embolism accounting for 23.1% of the deaths.
Pulmonary changes associated with Duchenne's muscular dystrophy include: A-a restrictive ventilatory defect B-an obstructive ventilatory defect C-decreased pulmonary artery pressures D-increased residual volume
A-restrictive ventilatory defect The combination of marked kyphoscoliosis and degeneration of the respiratory muscles produces a severe restrictive ventilatory defect in patients with Duchenne's muscular dystrophy. Pulmonary hypertension is also commonly seen.
Correct location of the catheter tip of a central venous line is in the: A-superior vena cava B-right atrium C-right ventricle D-pulmonary artery
A-superior vena cava The CVP catheter tip should not be allowed to migrate into the heart chamber to avoid arrhythmias and perforation.
In the pressure-volume loop below, cardiac work is best represented by: A-the area of the curve B-the slope of the line from points C to D C-the distance of the line from points C to D D-the slope of a line from points A to D
A-the area of the curve Cardiac work is the product of pressure and volume and is linearly related to myocardial oxygen consumption. Cardiac work is best represented by the area of the curve of a pressure-volume loop.
Ninety percent of congenital diaphragmatic hernias occur: A-through the left posterolateral foramen B-through the right posterolateral foramen C-through the anterior foramen D-along the inferior vena cava
A-through the left posterolateral foramen Left-sided herniation through the posterolateral foramen of Bochdalek accounts for 90% of diaphragmatic hernias. Hypoxia, scaphoid abdomen and evidence of bowel in the thorax are the hallmarks of diaphragmatic herniation. Peak airway pressures should not exceed 30 cm H2O to minimize the risk of pneumothorax during surgical correction.
Correct statements concerning the use of benzodiazepines in the elderly include: A-volume of distribution is increased B-reduced pharmacodynamic sensitivity is observed C-the elimination half-life of diazepam, but not midazolam, is increased D-all of the above
A-volume of distribution is increased Aging increases the volume of distribution for all benzodiazepines, effectively prolonging their elimination half-lives. Enhanced pharmacodynamic sensitivity is also observed. The elimination half-lives of both diazepam and midazolam are increased.
While monitoring somatosensory-evoked potentials, an increase in amplitude is noted. Of the options listed below, the most likely medication to have caused this increase in amplitude would be: A. Etomidate B. Propofol C. Midazolam D. Sevoflurane
A. Etomidate is known to increase the amplitude of somatosensory-evoked potentials (SSEPs), and can sometimes be dramatic. Propofol is considered to have minimal to no effect on amplitude, and is commonly used as an infusion for the maintenance of anesthesia when monitoring SSEPs. Midazolam has been shown to decrease amplitude, and this should be kept in mind when used for premedication
Fluid resuscitation is done with 4 L of normal saline. The potential acid-base abnormality that can occur is: A. Hyperchloremic acidosis B. Metabolic alkalosis C. Hyperkalemic acidosis D. Respiratory alkalosis
A. Hyperchloremic acidosis is a well-recognized entity as a consequence of large volume administration of some intravenous fluids. Normal saline (0.9% sodium chloride solution) and colloids suspended in normal saline are often infused because they are easily available, and are isotonic with plasma. When a patient is given normal saline (a hyperchloremic solution), chloride levels can significantly increase. It is the chloride anion that is the ultimate cause of the acidosis. Consider this equation: sodium chloride combines with water: NaCl + H2O → HCl + NaOH. The strong acid (HCl) and the strong base (NaOH) should cancel each other out, with no effect on pH. However, because the normal concentrations of Na+ and Cl − in the serum are 140 and 100, respectively, adding normal saline (154 mEq Na and 154 mEq Cl) causes the chloride to increase proportionately more than the sodium. This increase in chloride tips the acid-base balance toward HCl, thereby causing a metabolic acidosis
During rapid-sequence induction of anesthesia for emergent laparotomy to explore multiple stab wounds, a 45-year-old man vomits a large quantity of undigested food particles. During intubation of the trachea, food particles are noted near the cords. After instituting ventilation with 100% oxygen, the most appropriate next step in this patient's management is A. Place patient in Trendelenburg position B. Ventilate with positive end-expiratory pressure of 15 cm H2O C. Administer corticosteroids D. Administer antibiotics
A. Initial management involves the recognition of a possible aspiration event when there are visible gastric contents in the oropharynx. Once diagnosis is suspected, the patient should be placed in Trendelenburg position to limit pulmonary contamination, followed by suctioning of the oropharynx. Empirical antibiotic therapy is strongly discouraged unless it is apparent that the patient has developed a subsequent pneumonia. Corticosteroids should not be given prophylactically, as there is no evidence to support this practice.
A patient with methemoglobinemia will have a pulse oximetry reading that A. Converges around a saturation of 85% B. Converges around a saturation of 65% C. Converges around a saturation of 45% D. Varies widely
A. Many different clinical situations will cause pulse oximetry to read in characteristic patterns. Methemoglobinemia absorbs both wavelengths of light and tends to converge around a saturation of 85%. Carboxyhemoglobin only absorbs red light, but not infrared light, and can vary widely in saturation readings. Methylene blue, a common dye used during surgery, tends to cause saturations to converge around 65%.
If somatosensory-evoked potentials change significantly, the anesthesia provider should consider: A. Increasing blood pressure B. Hyperventilating the patient C. Cooling the patient D. Hemodilution
A. Medications are not the only variables that affect somatosensory-evoked potentials, as changes in physiology can also alter latency and amplitude. Amplitude decreases during episodes of hypotension, hypoxia, and hyperthermia. Latency can be increased during hypothermia, hypocarbia, and hemodilution/anemia
Normal pulmonary vascular resistance ranges between ______ (dynes)(s)/cm5: A. 50 and 150 B. 300 and 600 C. 900 and 1500 D. 1800 and 2100
A. Normal pulmonary vascular resistance ranges between approximately 50 and 150 (dynes)(s)/cm5.
During a complex mitral valve replacement, it is determined that the patient will benefit from brief protective hypothermia. Of the options listed below, core temperature is best measured via the: A. Tympanic membrane B. Bladder C. Nasopharnyx D. Rectum
A. Numerous sites can be used to monitor temperature in the operating room. Of the most common, tympanic membrane (perfused by carotid artery) and pulmonary artery measurements tend to be the best reflectors of core temperature, followed by bladder temperatures. Rectal temperatures overall tend to be a poor substitute, while axillary and skin temperatures are highly prone to error.
A morbidly obese 60-year-old man with a 65-pack year history of tobacco smoking is awake after an uncomplicated general anesthetic with sevoflurane for routine endoscopy and colonoscopy screening. After 45 minutes in the recovery room (PACU), while breathing 6 L/min of oxygen via nasal cannula, his pulse oximetry drops to 88%. His rest of the vital signs are stable, and the lungs are clear to auscultation. The most effective management at this point is: A. Coughing with deep breathing B. Reintubation of the trachea C. Intravenous administration of doxapram D. Continuous positive-airway pressure
A. Postsurgical atelectasis is treated by physiotherapy, focusing on deep breathing while encouraging coughing. An incentive spirometer is often used to promote full expansion of the lungs. Ambulation is also highly encouraged to improve lung inflation. These measures are considered first-line options for his presumed microatelectasis. In the smoker, coughing will also clear the airways of mucous to improve aeration. Doxapram stimulates chemoreceptors in the carotid bodies, which in turn stimulates the respiratory center in the brain stem to increase tidal volume and respiratory rate.
Degradation of sevoflurane by soda lime results in the production of : A. Compound A B. Compound B C. Compound C D. Compound D
A. Sevoflurane is degraded by soda lime, resulting in the production of a potentially nephrotoxic compound A. Compound A production is increased by using low fresh gas flow rates, using high concentrations of sevoflurane, and for long hours (>6 hours).
A 40-year-old man undergoing an open resection of a pheochromocytoma under isoflurane general endotracheal anesthesia suddenly develops tachycardia, hypertension, and multifactorial ventricular ectopy. Each of the following could be considered an appropriate treatment option, except A. Switching from isoflurane to sevoflurane B. Intravenous vasodilator C. Intravenous α-blocker D. Intravenous lidocaine
A. Switching from isoflurane to sevoflurane is not an appropriate method to treat the catecholamine storm, which can occur during direct surgical manipulation of the tumor. An α-blocker, vasodilator, and lidocaine are appropriate options to counter the effects of catecholamine storm
The Tec 6 desflurane vaporizer : A. Is electrically heated to 39°C B. Is pressurized to 3 atm C. Is pressure-compensated D. All of the above
A. The Tec 6 desflurane vaporizer is electrically heated to 39°C and pressurized to 2 atm. This is done because desflurane boils at room temperature at sea level (1 atm). The heating and pressurization optimizes the delivery of desflurane
A 38-year-old woman is set to undergo extracorporeal shock wave lithotripsy to disintegrate a painful stone trapped in her upper ureter. The patient is requesting an epidural anesthetic and is choosing to be otherwise awake and cooperative with her positioning and procedure. 47. The step of the epidural placement that should be avoided in this patient is A. Loss of resistance to air B. Loss of resistance to hanging drop C. Test dose injection D. Bolus dose of local anesthetics
A. With epidural anesthesia, consider avoiding the use of loss of resistance to air for identifying the epidural space, as air will provide an interface and cause dissipation of shock wave energy resulting in local tissue injury. Animal experiments have shown epidural tissue damage following injection of air followed by exposure to shock waves.
All of the following nerves provide sensory innervation to the foot, except A. Lateral femoral cutaneous nerve B. Sural nerve C. Deep peroneal nerve D. Superficial peroneal nerve
A. An ankle block can be performed by providing anesthesia and blocking the five nerves that innervate the foot, namely, the superficial and deep peroneal nerve, saphenous nerve, sural nerve, and posterior tibial nerve
Gas flowmeters: A. Are gas-specific B. Have a gas flow rate which depends on viscosity at high turbulent flows C. Have a gas flow rate which depends on density at low laminar flows D. Are cylindrical in shape
A. Are gas-specific. Gas flowmeters are calibrated for a particular gas. Gas flow rate depends on its viscosity at low laminar flows, and its density at high turbulent flows. Flowmeters are tapered in shape, with the diameter the smallest near the bottom of the tube.
The highest content of soda lime is: A. Calcium hydroxide B. Potassium hydroxide C. Sodium hydroxide D. Silica
A. Calcium hydroxide The highest content of soda lime is calcium hydroxide (75%). Other constituents include sodium (3%) and potassium hydroxide (1%), water (20%), and silica, which is added to produce hardness. An indicator dye, such as ethyl violet, is added to indicate the degree of exhaustion
At the end of the case as the drapes are taken down, diffuse microvascular bleeding is noted in this patient who required 15 U of blood during his intraoperative course. Platelet count is 40,000/mm3, prothrombin time is 18 seconds, activated partial thromboplastin time (PTT) is 54 seconds, D-dimer is 2,000 ng/mL, and serum fibrinogen concentration is 40 mg/dL. The most likely cause of bleeding is A. Disseminated intravascular coagulation (DIC) B. Abnormal platelet function C. Depressed levels of factor VIII D. Citrate toxicity
A. Coagulopathy following massive transfusion is a consequence of posttraumatic and surgical hemorrhage. Bleeding following massive transfusion can occur due to hypothermia, dilutional coagulopathy, platelet dysfunction, fibrinolysis, or hypofibrinogenemia. Transfusion of 15 to 20 U of blood products causes dilutional thrombocytopenia contributing to the bleeding. Excessive fibrinolysis and low fibrinogen are further causes of bleeding in these patients. The hemostatic signatures of DIC are low platelets, low fibrinogen, prolonged prothrombin, prolonged PTT, elevated D-dimers, and low antithrombin.
Which of the following is considered the most sensitive indicator of impending traumatic renal failure? A. Decreased creatinine clearance B. Decreased central venous pressure C. Decreased fractional excretion of sodium D. Increased urine osmolality
A. Creatinine clearance test evaluates how efficiently the kidneys clear creatinine from the blood. Creatinine, a waste product of muscle energy metabolism, is produced at a constant rate that is proportional to the muscle mass of the individual. Because the body does not recycle it, all of the creatinine filtered by the kidneys in a given amount of time is excreted in the urine, making creatinine clearance a very specific measurement of kidney function
Complex regional pain syndrome type IT (causalgia) is differentiated from complex regional pain syndrome type I (reflex sympathetic dystrophy) by knowledge of its A. Etiology B. Chronicity C. Affected body region D. Type of symptoms E. Rapidity of onset
A. Etiology Complex regional pain syndrome type I (reflex sympathetic dystrophy) is a clinical syndrome of continuous burning pain usually occurring after an injury or surgery. Patients present with variable sensory, motor, autonomic, and trophic changes. Complex regional pain syndrome type II (causalgia) exhibits the same features of reflex sympathetic dystrophy, but the etiology is damage to a major nerve.
Etomidate in a dose of 0.2 mg/kg can lead to all the following, except A. Abolish ventilatory response to carbon dioxide B. Increase amplitude and latency of somatosensory-evoked potentials (SSEPs) C. Decrease cerebral metabolic oxygen demand D. Decrease cerebral blood flow (CBF)
A. Etomidate decreases cerebral metabolic rate, CBF, leading to a decrease in intracranial pressure. It enhances SSEP. It is a sedative hypnotic but lacks analgesic properties. Ventilation is affected to a lesser extent with etomidate when compared to barbiturates or benzodiazepines. Induction doses usually do not result in apnea.
A medical student asks you if "young" blood is better for critically ill patients. Which of the following statements regarding "young" blood is most correct? A. Fresher blood has better ability to deliver oxygen to tissues B. Blood from younger donors has lower risk of immunosuppression than blood donated by the elderly C. Older blood has a lower potassium content D. Fresher blood can be transfused more rapidly than older blood.
A. Fresher blood (<5 days of storage) has been recommended for critically ill patients in an effort to improve the delivery of oxygen (2,3-diphosphoglycerate concentrations are better maintained with fresher blood). More recently, some evidence suggests that administration of younger blood (i.e., stored <14 days) is associated with better outcomes including decreased mortality rate and fewer postoperative complications, especially with major surgery
A patient with chronic bronchitis will likely show signs and symptoms of which of the following (choose 2) A. Increased residual volume (RV) B. Increased PaCÓ C. Increased elastic recoil D. Decreased hematocrit E. Decreased total lung capacity
A. Increased residual volume (RV) B. Increased PaCÓ Asthma is a restrictive lung disorder that can result in trapping of gases in the alveoli. This trapping of gases leaves an increase volume in the lungs and decreased expulsion of CÓ, thus the arterial tension of carbon dioxide increases.
Treatment of a patient with mannitol can lead to all the following, except A. Oliguria B. Hypotension C. Hypervolemia D. Hypokalemia
A. Mannitol, a six-carbon sugar, is the most commonly used diuretic in neuroanesthesia practice. It is an osmotic diuretic and undergoes little or no reabsorption. It also improves renal blood flow. Side effects include an initial increase in circulatory volume, which can cause pulmonary edema. Diuresis attributed to mannitol can lead to hypovolemia and hypokalemia
The addition of a vasoconstrictor (e.g epinephrine) to a local anesthetic (LA) solution causes all of the following consequences except: A. More pronounced effect with a long acting LA. B. Decreased absorption of LA into the surrounding tissues. C. Enhanced analgesia D. Limiting of the toxic side of LA.
A. More pronounced effect with a long acting LA. Prolongation of the duration of action of local anesthetics by addition of a vasoconstricting agent is more evident and pronounced in shorter-acting local anesthetics agents.
Which ligament must be transversed to enter the sacral canal? A. Sacrococcygeal ligament B. Interosseous ligament C. Sacral Ligament D. Cornual ligament
A. Sacrococcygeal ligament
When you instill the test dose of 1.5% lidocaine with 1:200,000 epinephrine when placing an epidural, what 2 things are you testing for? A. Subarachnoid injection B. Intravascular injection C. Lidocaine allergy D. Misplaced epidural tip in ligamentum flavum.
A. Subarachnoid injection B. Intravascular injection
The diastolic blood pressure recorded with an automated blood pressure cuff using the oscillometric method will be A. Approximately 10 mm Hg higher when compared to: direct arterial measurement B. Approximately 10 mm Hg lower when compared to direct arterial measurement C. Equal to direct arterial measurement D. Random and unreliable
A. The DINAMAP (device for indirect noninvasive automatic mean arterial pressure) method for measuring blood pressure uses an automated cuff that measures oscillometric variations with reduction in cuff pressure to calculate systolic, mean, and diastolic pressures. In general, diastolic measurements with DINAMAP are about 10 mm Hg higher with automated as opposed to direct arterial measurement, whereas systolic and mean pressures tend to correlate well.
A 45-year-old male is seen in the preadmission testing for pituitary adenoma resection surgery. All the following would be expected if this adenoma was causing acromegaly, except: A. Hypotension B. Obstructive sleep apnea C. Difficult airway D. Hyperglycemia
A. The acromegalic patient suffers from general overgrowth of skeletal, soft, and connective tissues. This results in coarse facial features and enlarged hands and feet. Patients may also have a difficult airway because of overgrowth of soft tissues of upper airway, enlargement of tongue and epiglottis, overgrowth of mandible with increased distance from lips to vocal cords, and glottic and subglottic narrowing. These changes may also lead to obstructive sleep apnea. Patients also are prone to hyperglycemia, hypertension, congestive heart failure, increased lung volumes, increased ventilation-perfusion mismatch, peripheral neuropathy, skeletal muscle weakness, osteoarthritis, and osteoporosis.
An interscalene block will typically deposit the local anesthetic between which of the following two muscles? A. Anterior and middle scalene muscles B. Middle and posterior scalene muscles C. Anterior and posterior scalene muscles D. Sternocleidomastoid and anterior scalene muscles
A. The brachial plexus nerve root/trunk is usually positioned between the anterior and middle scalene muscles. When local anesthetics are placed between these two muscle bundles, it is commonly referred to as an interscalene block.
A 51-year-old patient was an unrestrained driver in a motor vehicle crash in which he sustained multiple traumatic injuries. He is on mechanical ventilation, and has received 8 units of packed red blood cells, 4 units of fresh-frozen plasma, and 6 units of platelets. His arterial blood gas reveals a metabolic alkalosis. The most likely explanation for this finding is A. Metabolism of citrate to bicarbonate B. Under-resuscitation C. Continued bleeding D. Hypoventilation
A. The citrate in the blood preservative is metabolized to bicarbonate by the liver and can cause a metabolic alkalosis following a large-volume transfusion. Underresuscitation and bleeding are likely to cause a metabolic acidosis, whereas hypoventilation causes a respiratory acidosis
Most sensitive method to detect air embolism is A. Transesophageal echocardiogram (TEE) B. Decreased end-tidal carbon dioxide C. Increased end-tidal nitrogen D. Mill wheel murmur.
A. The most sensitive intraoperative monitor for detecting venous air embolism is TEE. The second best monitor is precordial Doppler sonography, which can detect as little as 0.25 mL of air. Changes in end-tidal respiratory gas concentrations, such as nitrogen and carbon dioxide, and changes in pulmonary artery pressures are less sensitive. Hypotension and mill wheel murmur are late manifestations of venous air
A patient with cholestasis presents for preoperative evaluation with laboratory findings revealing normal aspartate aminotransferase (serum glutamic-oxaloacetic transaminase) and prothrombin time but with a markedly elevated alkaline phosphatase. He will need a muscle relaxant for upcoming colon surgery. Which of the following anesthetic scenarios should be considered? A. Prolonged duration of vecuronium action B. Increase intubating dose of atracurium C. Prolonged duration of succinylcholine action D. Shortened duration of pancuronium action
A. The pharmacokinetics of many nondepolarizing muscle relaxants in the presence of cholestasis and obstructive jaundice may be altered. The prolonged duration of action likely results from both inhibition of hepatic uptake by the accumulated bile salts and a general deterioration of liver transport function. Succinylcholine, atracurium, and cis-atracurium have theoretical advantages because their elimination occurs via plasma cholinesterases and Hofmann degradation, respectively, mostly independent of renal or hepatic function.
Which of the following body fluid volumes in the adult (based on percentage of total body weight) is correct? (Pick all that apply) 1. Total body water 60% 2. Extracellular water 20% 3. Plasma volume 4% 4. Intracellular water 40%
ALL (E) In the adult, total body water is approximately 60% of total body weight. Of this, approximately two thirds is located in the intracellular space (40% of total body weight) and one third is located in the extracellular space (20% of total body weight). Plasma volume equals about one fifth of extracellular volume or 4% of total body weight in adults
Hazards associated with laser surgery include:(Select all the correct answers). I. Endotracheal tube fire 2. Atmospheric contamination 3. Ocular injury 4. Venous gas embolism
ALL ARE CORRECT. The term LASER refers to light amplification by stimulated emission of radiation. This device is capable of producing very intense beams of light that can be focused to produce controlled coagulation, incision, or vaporization of tissues. The primary advantage of using laser light is that edema and damage to surrounding tissues is minimal; thus healing is rapid. All of the choices listed in this question are potential disadvantages and hazards associated with laser surgery. In addition to those listed, another potential complication is that the personnel may be struck by a misdirected beam of light, causing bums to the skin and mucous membranes. Additionally, corneal bums are a possibility, emphasizing the need for personnel to wear safety glasses. Venous gas embolism can occur from the coolant gas used in conjunction with the laser. Because endotracheal tubes not made of metal may be ignited by the laser beam, inhaled concentrations of oxygen are typically maintained at the lowest concentrations acceptable (approximately 40%) and nitrous oxide, which can support combustion, is not usually administered.
Factor(s) that influence systemic absorption of local anesthetics include (Choose all that apply). 1. Site of injection of the local anesthetic 2. Lipid solubility of the local anesthetic 3. Addition of vasoconstrictor substances to the local anesthetic 4. Concentration of the local anesthetic
ALL, All of the choices are correct. The amount of systemic absorption of a local anesthetic depends on the total dose injected, the vascularity of the injection site, the speed of injection, whether or not a vasoconstrictor is added to the local anesthetic solution, and the physicochemical properties of the local anesthetic, such as protein and tissue binding, lipid solubility, and the degree of ionization at physiologic pH. For all local anesthetics, systemic absorption is greatest after injection for intercostal nerve and caudal blocks, intermediate for epidural blocks, and least for brachial plexus and sciatic nerve blocks.
Upon evaluating your patient's epidural placed 3 days ago for a transhiatal esophagectomy, you notice that she is jaundiced with a mild fever of 38 degrees C. Her hemoglobin is 7 mg/dL. She looks well otherwise. She received two units of blood intraoperatively for an estimated blood loss of 700 mL. You suspect that she is having a delayed hemolytic transfusion reaction. Which of the following statements would be true about this patient? A. You gave her ABO-incompatible blood. B. Th e blood bank failed to detect antibodies. C. Th e transfused blood was old and largely hemolyzed. D. Th is patient is bleeding and will need to be re-explored. E. Th is is a very common phenomenon.
ANSWER : B This case describes a delayed hemolytic transfusion reaction , which usually occurs 3 to 7 days aft er transfusion. Common clinical signs include mild fever with or without chills, moderate jaundice, and an unexplained decrease in hemoglobin following transfusion. Its incidence is estimated to be less than 1 in 2,000 transfusions. Antibodies formed from either previous transfusion exposure or pregnancy (common) or through primary alloimmunization (less common) increase in the days aft er a transfusion, which then bind to the transfused red blood cells to form antigen-antibody complexes. These complexes are removed by the reticuloendothelial system with subsequent extravascular hemolysis, leading to increased bilirubin levels and jaundice. Because these antibodies are generally at low titers before transfusion, they are frequently missed by usual cross-matching procedures. Unlike immediate hemolytic transfusion reactions, delayed hemolytic transfusion reactions rarely progress to hemodynamic instability, renal failure, or disseminated intravascular coagulation. Th e transfusion of ABO-incompatible blood would result in immediate hemolysis and severe symptoms, mediated via IgM antibodies. Most of the blood released by the blood bank is considered "older" because near-expiring blood will be used fi rst. Nevertheless, all blood still must meet the FDA criteria of 75% transfused red blood cells surviving for 24 hours. Consequently, the hemolysis in "old" blood would not be signifi cant enough to cause this patient's jaundice. Th e patient appears to be stable without evidence of bleeding, and does not need to head back to the operating room for re-exploration. A direct antiglobulin test (Coombs test) should be sent and will be positive in nearly all instances of a delayed transfusion reaction.
A previously healthy 29-year-old G1P0 patient is admitted with the diagnosis of preeclampsia and is treated with an intravenous infusion of magnesium sulfate. Later, her serum magnesium level is found to be 10 mEq/L. Which of the following is MOST correct regarding magnesium? A-ECG changes associated with hypermagnesemia include prolongation of the P-R interval and widening of the QRS complex. B-Increased levels of magnesium are associated with vasoconstriction and exacerbation of hypertension. C-Magnesium is a substance that cannot be removed via dialysis. D-Should she require general anesthesia, her dose of non-depolarizing muscle relaxant should be increased by 25%.
ANSWER = A Pathologic increases in the levels of serum magnesium are frequently due to excessive intake (magnesium containing antacids, laxatives, or treatment during pregnancy induced hypertension and preeclampsia). Loss of deep tendon reflexes occurs at 10 mEq/L, with the risk of cardiac depression, ECG changes, and ultimately respiratory arrest increasing as levels rise. ECG changes are inconsistent, but frequently show a widening of the QRS complex and a prolongation of the P-R interval. Increased levels of magnesium are associated with a drop in SVR and hypotension, not hypertension. Magnesium interferes with the release of acetylcholine, thus potentiating neuromuscular blocking drugs so the dose would need to be decreased, not increased. Magnesium can be dialyzed if necessary.
Anatomic dead space for a 70-kg man is approximately: A. 140 mL B. 240 mL C. 350 mL D. 500 mL E. 630 mL
ANSWER: A In adults anatomic dead space is approximately 2 mL/kg. Dead space may be measured using Fowler's method, in which the subject takes a single breath of 100% oxygen and then exhales. Th e nitrogen concentration is measured continuously. As exhalation begins there is no nitrogen exhaled because the conducting airways contain 100% oxygen. As gas begins to empty from the alveoli, nitrogen levels rise steadily up to a plateau. Th e anatomic dead space is the volume of gas exhaled from the start of exhalation to the midpoint of the rising phase of the exhaled nitrogen
The ratio of carbon dioxide eliminated to oxygen consumed by the lungs is called A. Respiratory quotient B. Dead-space-to-tidal-volume ratio C. Alveolar ventilation D . Alveolar carbon dioxide equation E. Metabolic Equivalent
ANSWER: A The respiratory quotient is the ratio of carbon dioxide eliminated to oxygen consumed by the lungs. This ratio varies between 0.7 and 1.0 based on inputs to metabolism. When carbohydrates are consumed as energy, the ratio is 1 because 6 molecules of oxygen are consumed to make 36 ATP and 6 molecules of carbon dioxide. When fat is converted to ATP, 23 molecules of oxygen are consumed while 16 molecules of carbon dioxide are produced, which gives a respiratory quotient of 0.7. Th e respiratory quotient is assumed to be 0.8 for use in the alveolar gas equation. Dead-space-to-tidal-volume ratio measures the ratio of the volume that does not participate in gas exchange to the volume of a normal breath. Alveolar ventilation is the rate at which carbon dioxide is removed from the alveolus and is the volume of gas that participates in gas exchange. Th e alveolar carbon dioxide equation expresses the relationship between carbon dioxide production and alveolar ventilation. The Metabolic Equivalent (MET) is a concept expressing the energy cost of a given physical activity. As an example, watching television is a MET of 1; jumping rope is a MET of 10.
Please fill in the gaps. Increasing lung volumes will _____ airway length and will _____airway diameter, with net effect of _____ airflow resistance. A. Increase, increase, decreased B. Increase, not change, increased C. Decrease, decrease, decreased D . Not change, increase, decreased E. Not change, decrease, decreased
ANSWER: A Increasing lung volume will increase airway length as well as increase airway diameter. Th e net eff ect of this change is to decrease airflow resistance because, according to Poiseuille's law, resistance is proportional to changes in the length of a tube and inversely proportional to the fourth power of the radius. Thus, a small increase in the diameter of the airways will make a larger reduction in airway resistance than a small increase in length.
Compared to opiate-only epidural infusion, use of a combination of local anesthetic and opioid epidural infusion leads to: A. Increased incidence of motor blockade B. Increased incidence of pruritus C . Increased incidence of breakthrough pain D . Decreased incidence of hypotension E . Increased incidence of respiratory depression
ANSWER: A By adding a local anesthetic to the opiate in the epidural infusion, there is a decreased requirement of the opioid concentration, which will lead to overall decreased opioid use. Th is leads to decreased opiate side eff ects such as pruritus, nausea, and respiratory depression. Th e local anesthetic, on the other hand, can cause motor blockage and sympathectomy, which leads to an increased incidence of hypotension. Motor blockade and sympathectomy are not seen with opiate-only epidural infusion. Finally, the combination of opiates and local anesthetics leads to superior analgesia, including improved dynamic pain relief, leading to decreased breakthrough pain.
Compared to opiate-only epidural infusion, use of a combination of local anesthetic and opioid epidural infusion leads to: A. Increased incidence of motor blockade B. Increased incidence of pruritus C . Increased incidence of breakthrough pain D . Decreased incidence of hypo-tension E . Increased incidence of respiratory depression
ANSWER: A By adding a local anesthetic to the opiate in the epidural infusion, there is a decreased requirement of the opioid concentration, which will lead to overall decreased opioid use. Th is leads to decreased opiate side effects such as pruritus, nausea, and respiratory depression. Th e local anesthetic, on the other hand, can cause motor blockage and sympathectomy, which leads to an increased incidence of hypotension. Motor blockade and sympathectomy are not seen with opiate-only epidural infusion. Finally, the combination of opiates and local anesthetics leads to superior analgesia, including improved dynamic pain relief, leading to decreased breakthrough pain.
All of the following nerves can be blocked in the axilla EXCEPT : A. Axillary nerve B. Musculocutaneous nerve C. Median nerve D. Ulnar nerve E. Intercostal brachial nerve
ANSWER: A In the axilla, the radial, ulnar, and median nerves are oft en traveling with the axillary artery and are blocked individually or sometimes together. Th e musculocutaneous nerve can be blocked as it runs in the coracobrachialis muscle. Th e intercostobrachial nerve (T2), which is not part of the brachial plexus, can be blocked in the axilla by injecting a subcutaneous band of local anesthetic on the medial surface of the arm in the axilla. Th is aids with pain as a result of tourniquet application. Th ere is no motor innervation with the intercostobrachial nerve. The axillary nerve is one of five terminal branches of the brachial plexus, but is not blocked in the axilla
All of the following nerves can be blocked in the axilla EXCEPT A. Axillary nerve B. Musculocutaneous nerve C. Median nerve D.. Ulnar nerve E. Intercostal brachial nerve
ANSWER: A In the axilla, the radial, ulnar, and median nerves are often traveling with the axillary artery and are blocked individually or sometimes together. The musculocutaneous nerve can be blocked as it runs in the coracobrachialis muscle. Th e intercostobrachial nerve (T2), which is not part of the brachial plexus, can be blocked in the axilla by injecting a subcutaneous band of local anesthetic on the medial surface of the arm in the axilla. This aids with pain as a result of tourniquet application. There is no motor innervation with the intercostobrachial nerve. The axillary nerve is one of five terminal branches of the brachial plexus, but is not blocked in the axilla.
The ventilation/perfusion ratio throughout the lung can be described as A. Highest at the apex B. Highest in the middle of the lung C. Highest at the base D. Highest in lower two-thirds of the lung E. Constant throughout the lung
ANSWER: A In the normal, upright lung both ventilation and perfusion increase from the apex to the base. Th e base of the lung receives more ventilation than the apex because alveoli are smaller and more compliant, and it receives more perfusion than the apex because there is greater intravascular pressure and lower resistance at the base. Moving inferiorly down the lung there is a greater increase in perfusion than ventilation. Th erefore, the ventilation/perfusion ratio is greatest at the apex and lowest at the base.
All of the following laboratory tests may help confirm the presence of hemolysis EXCEPT A. Tryptase B. LDH C. Haptoglobin D. Bilirubin E. Hemoglobin
ANSWER: A Many of the tests for hemolysis , including LDH, reticulocyte count, haptoglobin, and bilirubin, are nonspecific, and abnormal values only help support clinical suspicion of hemolysis. Often the first clue is anemia, and thus the hemoglobin value is important. Erythrocyte adenylate kinase, a red cell enzyme released from red blood cells, has been shown to be highly sensitive and specific in vitro and in vivo. It can be measured by rapid electrophoresis or immunologic methods but has not been widespread, likely due to availability. There are other tests for hemolysis, including plasma hemoglobin and urine hemosiderin, both of which are not frequently ordered. The gold standard is the chromium red cell survival test, but it is not used because of slow result reporting. Lactate dehydrogenase is oft en a marker of tissue breakdown or turnover and is abundant in red blood cells. Although elevations of LDH could indicate hemolysis, it serves as a clinical marker for myocardial infarction, tissue turnover, Pneumocystis pneumonia, and differentiation of exudates from transudates. Haptoglobin, a serum protein that binds free hemoglobin, is usually decreased in hemolysis. As an acute phase reactant, levels can be elevated in any inflammatory process or stress response. A positive direct Coombs test, a direct antiglobulin test (DAT), would indicate an immunologic process in hemolysis. It is usually weakly positive because the transfused cells are small relative to the patient's blood volume. β -tryptase levels are elevated in most patients with anaphylaxis associated with hypotension. It is released with mast cells along with histamine but it diffuses more slowly, with a half-life of 1.5 to 2.5 hours, as opposed to histamine, which would return back to normal within 30 minutes. Tryptase levels may be elevated if the transfused blood caused anaphylaxis, but this question is looking for tests suggesting hemolysis.
Which of the following is NOT a side effect of neuraxial opioids in the obstetric patient? A . Neurotoxicity B. Pruritus C . Hypotension D. Respiratory depression E. Reactivation of oral HSV infection
ANSWER: A Neuraxial opioids can lead to sensory changes, as well as nausea and vomiting, pruritus, hypotension, respiratory depression as well as urinary retention. In one study, reactivation of oral HSV was found to occur in 10% of parturients who received epidural morphine and in only 1% of patients who did not receive epidural morphine. Parenteral opioids also cause delayed gastric emptying. Intrathecal administration of fentanyl produces greater delays in gastric emptying compared to epidural fentanyl administration. Neurotoxicity is not associated with intrathecal or epidural administration of opioids; however, concentrated local anesthetic (lidocaine) in the intrathecal space is associated with transient neurologic symptoms.
Which of the following statements is TRUE regarding a femoral nerve block? A. The femoral nerve is located below both the fascia lata and fascia iliaca. B . Stimulation of the sartorius muscle will lead to r eliable anesthesia in the femoral nerve distribution. C. The femoral nerve is approximately 1 cm medial to the femoral artery. D . A femoral nerve block can provide complete anesthesia for a femoral fracture. E. The needle entry point for a fascia iliaca block is at the intersection of the lateral two-thirds and the medial one-third of the line connecting the pubic tubercle and anterior superior iliac spine (inguinal ligament).
ANSWER: A Th e femoral nerve is located 1 cm lateral to the femoral artery, which is lateral to the femoral vein. Th e nerve is located deep to the fascia lata and fascia iliacus (two "pops") and can be blocked by performing a fascia iliaca compartment block. Stimulation of the sartorius muscle will not provide reliable anesthesia in the femoral distribution. A quadriceps twitch/patellar retraction is required for reliable anesthesia. A properly placed femoral block should provide anesthesia for a patellar fracture, but not necessarily a femoral fracture, as the femoral nerve supplies only the anterior thigh, but not lateral, medial, or posterior thigh. For a fascia iliaca block, the intersection of the medial twothirds and the lateral one-third of the line is used (well away from the femoral artery).
The subdural space: A. Exists between the dura mater and arachnoid mater B. Contains CSF C. Exists between the dura mater and ligamentum fl avum D. Can be easily found in all patients E. Will produce reliable anesthesia and analgesia
ANSWER: A Th e potential space between the dura mater and arachnoid mater is called the subdural space. It does not contain CSF, but may contain a very small amount of serous fl uid. Accidental subdural injection may occur during both attempted epidural and intrathecal injection and characteristically leads to a patchy block. It has been estimated to occur in less than 1% of intended epidural injections. Th e space between the dura mater and ligamentum flavum is the epidural space.
At any given pressure, lung volumes during deflation will be A. Greater than lung volumes during inflation B. Less than lung volumes during inflation C. Equal to lung volumes during inflation D. Independent of transpulmonary pressure E. Independent of surface tension.
ANSWER: A The compliance of the lung is greater during defl ation than during inflation. This behavior is called hysteresis. Hysteresis means that more than expected pressure is required during inflation, yet less than expected recoil pressure is present during deflation of the lungs. Th is is largely due to the effects of surface tension, which increases the energy needed to recruit alveoli during inspiration.
After receiving a local anesthetic injection for a sciatic nerve block, a patient develops tinnitus, circumoral paresthesia, and dizziness. Assuming equal-volume amounts, which of the following is MOST likely to have caused these symptoms? A. 0.75% bupivacaine B . 2% lidocaine C. 0.75% levobupivacaine D. 0.75% ropivacaine E. 2% mepivacaine
ANSWER: A The patient is exhibiting signs of CNS toxicity , most likely from local anesthetic administration. A doubleblind crossover study of volunteers showed no difference between levo(S−)bupivacaine and ropivacaine in terms of time to first onset of CNS symptoms and mean total volume of study drug administered at the onset of symptoms. Other studies have shown that 10% to 25% larger doses of levobupivacaine and ropivacaine than bupivacaine can be administered before signs of CNS toxicity occur. Lidocaine and mepivacaine are less likely than bupivacaine to produce CNS and cardiac toxicities.
After receiving a local anesthetic injection for a sciatic nerve block, a patient develops tinnitus, circumoral paresthesia, and dizziness. Assuming equal-volume amounts, which of the following is MOST likely to have caused these symptoms? A. 0.75% bupivacaine B . 2% lidocaine C. 0.75% levobupivacaine D. 0.75% ropivacaine E. 2% mepivacaine
ANSWER: A The patient is exhibiting signs of CNS toxicity , most likely from local anesthetic administration. A doubleblind crossover study of volunteers showed no difference between levo(S−)bupivacaine and ropivacaine in terms of time to first onset of CNS symptoms and mean total volume of study drug administered at the onset of symptoms. Other studies have shown that 10% to 25% larger doses of levobupivacaine and ropivacaine than bupivacaine can be administered before signs of CNS toxicity occur. Lidocaine and mepivacaine are less likely than bupivacaine to produce CNS and cardiac toxicities.
The relationship between pressure within a sphere and the tension in the wall is described by A Laplace's Law B. Dalton's Law C. Boyle's Law D. Poiseuille's Law E. Fick's Law
ANSWER: A Elastic recoil of the lung is influenced by the surface tension at the air-liquid interface of the alveoli. The relationship between this surface tension and the pressure within a sphere, such as an alveoli, can be described by Laplace's Law. According to Laplace's Law the pressure within the sphere ( P s ) is equal to two times the wall tension ( T ) divided by the radius of the sphere.
What is the most common noninfectious adverse reaction associated with blood product transfusion? A. Transfusion-related immunomodulation (TRIM) B. Transfusion-related acute lung injury (TRALI) C. Anaphylactic/anaphylactoid reactions D. Alloimmunization E . Acute hemolytic transfusion reactions
ANSWER: A With modern blood-banking practices, the infectious complications of transfusion have decreased to a point where noninfectious complications have become more prominent. The transfusion of blood products have been shown to have immunomodulatory effects since the 1970s, when blood transfusions improved graft survival aft er kidney transplantation. Transfusion-related immunomodulation (TRIM) may also have some sort of inflammatory effect, but its true clinical scope is uncertain. It is oft en thought to be a possible reason for cancer recurrence, postoperative infection, virus activation, and in organ dysfunction and mortality. Alloimmunization is the development of antibodies to the transfused blood products
Y our next patient for femoro-femoral bypass also has a bleeding disorder. Fortunately he has seen a hematologist, who has diagnosed him as having vWD type 3. What is the best treatment for this patient? A. DDAVP B . v WF/factor VIII concentrates C. Cryoprecipitate D. Fresh frozen plasma E. Platelets
ANSWER: B Patients with vWD type 3 have a severe deficiency in vWF and factor VIII. vWF/factor VIII concentrates, like Humate-P, have been used safely and eff ectively for treatment and prophylaxis of severe vWD disease for the past 20 years. Risks of using these concentrates include the potential for viral and prion transmission (as it is derived from plasma), and the potential for thromboembolic events. Although vWD is oft en categorized as a platelet disorder, neither the platelet number nor platelet function is reduced. Cryoprecipitate is derived from fresh frozen plasma but with higher concentrations of fi brinogen, vWF, and factor VIII. Thus, if specific factor concentrates were not available, cryoprecipitate is an alternative. Fresh frozen plasma does not contain much vWF or factor VIII, which makes it a poor treatment for vWD type 3. While DDAVP increases the factor VIII activity in vWD type 1, the most common (75%) and mildest form, it would not increase factor levels enough for vWD type 3. Plasma factor VIII is the most important determinant of surgical and soft -tissue bleeding, and replacement therapy monitoring may be needed every 12 hours.
Which of the following interventions would most likely increase hypoxic pulmonary vasoconstriction? A .Increase of pulmonary arterial PÓ B. Decrease of alveolar PÓ C . Increase of pulmonary arterial Pcó D. Increase of alveolar Pcó E. Decrease of alveolar Pcó
ANSWER: B Hypoxic pulmonary vasoconstriction (HPV) occurs in small pulmonary arterial vessels in response to a decrease of both pulmonary arterial PÓ as well as alveolar PÓ . Both pulmonary arterial and alveolar PÓ stimulate HPV; however, there is a larger influence from decreasing alveolar PÓ . Regional HPV helps divert pulmonary blood fl ow away from regions of the lung in which P Ó is low and is important in helping to maintain ventilation/perfusion relationships throughout the lung. An increased pulmonary or alveolar Pc ó can also increase HPV but to a lesser extent than pulmonary or alveolar Páo .
Which of the following would INCREASE diffusion of a gas across the alveolar-capillary surface? A . Decreased alveolar surface area B. Decreased molecular weight of the gas C. Decreased partial pressure difference of the gas D. Decreased solubility of the gas E. Decreased temperature of the gas
ANSWER: B Fick's law of diffusion states that the diffusion of a gas across a sheet of tissue is proportional to the surface area of the tissue ( A) , the diffusion constant for the specific gas ( D) , and the partial pressure difference on each side of the tissue ( P 1 -P 2 ), and is inversely related to the tissue thickness ( T ). Diff usion of gas α = [A × D × (P 1 -P 2 )]/T, where D = solubility/ √ molecular weight
Your patient for a total hip replacement under spinal anesthesia received 3 units of packed red blood cells over the past hour and started to scratch her skin repeatedly. You notice that she has developed hives. Her vital signs are stable and unchanged and she is afebrile. Which of the following statements is INCORRECT regarding allergic transfusion reactions? A. Hypotension, bronchospasm, edema, and angioedema are other possible signs and symptoms B. Leukoreduction may reduce the rates of allergic reactions. C. IgA deficiency is often associated with allergic reactions. D. Most anaphylactic and anaphylactoid reactions have no detectable cause. E. Transfusion should be discontinued.
ANSWER: B Leukoreduction decreases the frequency and severity of nonhemolytic febrile transfusion reactions (NHFTRs), not allergic transfusion reactions, following red blood cell and platelet transfusions. Allergic transfusion reactions are a diagnosis of exclusion and generally not life-threatening. It is caused by cytokines and/or recipient antibodies reacting with donor leukocytes in patients receiving frequent transfusions. Laboratory evaluation for acute hemolytic transfusion reactions, the most serious being the transfusion of ABO-incompatible red blood cells, includes the direct antigen test, urine and plasma hemoglobin, and tests for hemolysis (e.g., LDH, haptoglobin, bilirubin). IgA deficiency is associated with allergic reactions, and knowing a patient has IgA deficiency allows preparation for future blood transfusions. Distinguishing one type of transfusion reaction from another is difficult. Both urticaria and anaphylaxis are due to antibody-allergen interaction causing mast cell degranulation and other mediator responses. It is best to stop the transfusion in case this is an early anaphylactic reaction without hemodynamic compromise. Even under careful exploration, the cause of anaphylaxis may never be known. Thus, careful planning regarding future blood transfusions is warranted.
32-year-old G1P0 parturient at 36 weeks with a history of complete spinal cord transaction that occurred 6 months ago resulting in paraplegia presents to labor and delivery. Which of the following is TRUE? A. A labor epidural is not indicated if patient has a T5-level transaction if she has no motor or sensory function below T5. B. Autonomic hyperreflexia does not develop if the lesion is below spinal dermatome T7. C. Use of succinylcholine is contraindicated. D . Hypertension, flushing, and headaches are likely signs of preeclampsia in this patient. E. Because of lack of sensory connection to the cortex, a full bladder is well tolerated in this patient.
ANSWER: B A review of 300 patients with spinal cord injury has shown that autonomic hyperreflexia does not develop if the lesion is below T7. The trigger could be a cutaneous, proprioceptive, or visceral stimulus (full bladder is a common trigger) that leads to sympathetic discharge without upper-level inhibition. This results in hypertension, bradycardia, and headaches. Vasodilation occurs above the level of the lesion, resulting in flushing of the head and neck. The patient may develop these symptoms without experiencing any pain. An epidural is recommended to blunt the sympathetic discharge. The intermediate period, often quoted between 3 days to 6 months, is the period when marked hyperkalemia occurs as a result of succinylcholine administration.
A type and screen involves all of the following EXCEPT A. Mixing recipient serum with commercially available O − red blood cells with phenotypes for common antigens. B. Mixing recipient serum with donor red blood cells C. Mixing recipient serum with type A and B red blood cells D. Mixing recipient red blood cells with anti-A and anti-B antibodies E. Mixing recipient serum with Rh-positive red cells
ANSWER: B A type and screen involves determining the ABO-Rh type of the recipient and screening for antibodies in his or her sera. The sample is first spun down and separated into serum/plasma and red blood cells. The recipient's red blood cells are first mixed with serum containing anti-A and anti-B antibodies to determine ABO blood type. Confirmation of blood type is then performed by mixing the recipient's serum with red blood cells with known A and B antigen. The Rh type is determined next by mixing anti-D antibodies with the recipient's red cells. If the no agglutination occurs, the patient is Rh-negative. Because anti-D antibodies can be present in someone who is Rh-negative (i.e., a mother being sensitized by fetal red blood cells during a previous childbirth), the recipient's serum is then mixed with Rh-positive red cells to test for its presence. The antibody screen tests for antibodies in the recipient's serum that may cause a transfusion reaction or reduce survival of transfused red blood cells. It involves mixing the recipient's serum with commercially available O − red blood cells with phenotypes for common antigens such as Kell, Duff y, and Lutheran. A positive antibody test requires further investigation and identification of the specific antibody. The chances of a serious transfusion reaction from typed and screened blood are estimated to be less than 1 in 10,000. A type and cross-match involves mixing recipient serum with donor red cells both at room and physiologic (37 degrees C) temperatures. Incubation at physiologic temperature aids in the detection of incomplete antibodies that may bind to red blood cell antigens but do not cause agglutination. Although exceedingly uncommon, these incomplete antibodies can cause hemolytic transfusion reactions. Th us, the cross-match simulates the actual blood transfusion and confi rms compatibility of the donor unit.
. A 58-year-old, 90-kg man is scheduled to undergo an open repair of a 5.6-cm infra-renal abdominal aortic aneurysm. He is a Jehovah's Witness and refuses any blood products. His past medical history includes coronary artery disease with stable angina and non-insulin dependent diabetes mellitus. His Hgb level is 14. He asks whether acute normovolemic hemodilution would be an option. Which of the following factors would be the biggest concern in using this technique? A. His current hemoglobin level B. His history of coronary artery disease C. That he has not been started on erythropoietin D. His being a Jehovah's Witness E. His history of diabetes mellitus
ANSWER: B Acute normovolemic hemodilution (ANH) is a technique in which the patient's blood is removed while replacing it with an equal intravascular volume of crystalloid or colloid prior to surgery or surgical blood loss. Theoretically, less red blood cell mass and coagulation factors are lost per milliliter of blood compared to nondiluted blood. Absolute contraindications to ANH include severe sepsis, hypovolemia, uncompensated congestive heart failure, and anemia. Relative contraindications include moderate to severe cardiac, pulmonary, renal, or liver disease. The severity of the patient's comorbidities should guide the degree of hemodilution and type of monitoring to perform the technique safely. A starting hemoglobin of more than 11 to 12 is recommended for ANH. Th us, the patient's current hemoglobin should be adequate. Diabetes mellitus is not a contraindication to ANH. The patient's stable angina implies that there is an increased risk for myocardial ischemia. Withdrawing blood decreases oxygen-carrying capacity, thereby decreasing the margin of safety for adequate oxygen delivery. This, coupled with the increased myocardial demand during aortic cross-clamping, increases the risk of myocardial ischemia and cardiac comorbidity, and would be the biggest concern in using this technique.
Given equal-volume infiltrations for local anesthesia, which of the following would be associated with a higher risk for inducing cardiac arrhythmias? A. 0.5% racemic bupivacaine B. 0.5% R(+) bupivacaine C. 0.5% S(−) bupivacaine D . 0.5% levo-bupivacaine E . 0.5% ropivacaine
ANSWER: B All local anesthetics cause a dose-dependent prolongation of cardiac conduction, as evidenced by increased PR intervals and QRS durations on the EKG. This is related to persistent blockade of sodium channels, which predisposes the heart to re-entrant arrhythmias. Since the dissociation constant of bupivacaine is almost 10 times greater than that of lidocaine, bupivacaine is more likely than lidocaine to cause cardiac depression. Local anesthetics also affect potassium channel conduction, prolonging the QTc interval and enhancing inactivation of sodium channels. Th e dextrorotatory (R+) isomer of bupivacaine is 7 times more potent in blocking potassium channels than the levo-rotatory (S−) isomer. Cardiac toxicity is also related to the lipid solubility and potency of local anesthetics. R(+) bupivacaine has the highest cardiotoxic potency. Racemic bupivacaine is less cardiotoxic (a mixture of R and S), followed by S(−) bupivacaine, then ropivacaine. Ropivacaine is a single levorotatory isomer. Levo-bupivacaine is the same as S(−) bupivacaine. Th e "R" and "S" prefi xes specify the characteristics of a specifi c chiral center while the "D" and "L" refer to the physical property of rotating polarized light clockwise or counterclockwise, respectively.
All of the following statements are TRUE regarding cocaine EXCEPT: A. Cocaine acts as a sodium channel blocker. B. Cocaine causes release of catecholamines, leading to hypertension and tachycardia. C . Cocaine is an aminoester. D . Cocaine blocks reuptake of catecholamines, leading to cerebrovascular accidents, myocardial infarctions, and arrhythmias. E. Cocaine is metabolized by hepatic carboxylesterases.
ANSWER: B Cocaine is a local anesthetic, and all local anesthetics are sodium channel blockers. Th ere are two major classes of local anesthetics, aminoesters (cocaine, procaine, and tetracaine) and aminoamides (lidocaine, mepivacaine, ropivacaine, and bupivacaine). All amides are more stable in solution. Aminoesters are hydrolyzed by plasma esterases, except cocaine, which is metabolized by hepatic carboxylesterases. Aminoamides undergo enzymatic breakdown in the liver. Cocaine prevents reuptake of catecholamines, leading to hypertension, tachycardia, angina, myocardial infarctions, and strokes. It does NOT cause release of catecholamines
A patient breathing 100% oxygen has an alveolar- arterial (A-a) gradient of 200 mm Hg. Th is patient's estimated transpulmonary shunt is A. 5% B. 10% C. 15% D. 20% E. 25%
ANSWER: B When the arterial PÓ is greater than 150 mm Hg, the degree of venous admixture can be estimated as approximately 1% for every 20-mm Hg increase in the A-a gradient. In this example, 200 mm Hg would equate to a trans-pulmonary gradient of 10%.
Given equal-volume infiltrations for local anesthesia, which of the following would be associated with a higher risk for inducing cardiac arrhythmias? A. 0.5% racemic bupivacaine B. 0.5% R(+) bupivacaine C. 0.5% S(−) bupivacaine D . 0.5% levo-bupivacaine E . 0.5% ropivacaine
ANSWER: B All local anesthetics cause a dose-dependent prolongation of cardiac conduction, as evidenced by increased PR intervals and QRS durations on the EKG. This is related to persistent blockade of sodium channels, which predisposes the heart to re-entrant arrhythmias. Since the dissociation constant of bupivacaine is almost 10 times greater than that of lidocaine, bupivacaine is more likely than lidocaine to cause cardiac depression. Local anesthetics also affect potassium channel conduction, prolonging the QTc interval and enhancing inactivation of sodium channels. Th e dextrorotatory (R+) isomer of bupivacaine is 7 times more potent in blocking potassium channels than the levo-rotatory (S−) isomer. Cardiac toxicity is also related to the lipid solubility and potency of local anesthetics. R(+) bupivacaine has the highest cardiotoxic potency. Racemic bupivacaine is less cardiotoxic (a mixture of R and S), followed by S(−) bupivacaine, then ropivacaine. Ropivacaine is a single levorotatory isomer. Levo-bupivacaine is the same as S(−) bupivacaine. Th e "R" and "S" prefi xes specify the characteristics of a specifi c chiral center while the "D" and "L" refer to the physical property of rotating polarized light clockwise or counterclockwise, respectively.
You are caring for a 25-year-old otherwise healthy patient in the PACU who is currently breathing room air with an oxygen saturation of 85%. A blood gas study reveals an arterial PÓ of 55 mm Hg and an arterial Pcó of 70 mm Hg. Which of the following is the most likely cause of this patient's hypoxemia? A. Right-to-left intracardiac shunt B. Hypoventilation C. Atelectasis D. Pulmonary embolism E . Intrinsic lung disease
ANSWER: B Interpreting this patient's blood gas study is helpful in determining the etiology of the hypoxemia. Knowing that the patient is breathing room air, we are able to calculate the expected Pa ó using the alveolar gas equation: expected Pa ó = (P B − P H2O ) × FiO 2 − (Pa có /R). Assuming arterial Pc ó equals alveolar Pc ó and a respiratory quotient of 0.8, this patient's expected Pa ó is 62.5 mm Hg. We can then evaluate the patient's alveolar-arterial (A-a) gradient. In this case the A-a gradient is 62.5 − 55 = 7.5 mm Hg. Th is is a normal A-a gradient, adjusted for age using the formula (Age + 10)/4. Given a normal A-a gradient, it is most likely that this patient's hypoxemia is secondary to hypoventilation. Another potential cause of hypoxemia in the setting of a normal A-a gradient is decreased FiO 2 . Th e other causes of hypoxemia all cause a widened A-a gradient.
All of the following are TRUE regarding neuraxial anesthesia EXCEPT A. Neuraxial anesthesia blunts the body's stress response to surgery. B. Neuraxial anesthesia leads to increased bleeding due to vasodilation. C. Neuraxial anesthesia decreases the incidence of postoperative thromboembolic events. D. Neuraxial anesthesia decreases perioperative morbidity and mortality in high-risk patients. E. Neuraxial anesthesia can be used to extend analgesia into the postoperative period.
ANSWER: B Neuraxial anesthesia has been shown to decrease intraoperative blood loss, as well as decrease the body's stress response, decrease the incidence of thromboembolic events, and decrease perioperative morbidity and mortality. Both spinals and epidurals can be used to extend analgesia into the postoperative period. Injecting morphine into the intrathecal spaces as well as the epidural space prolongs analgesia beyond the intraoperative period. In addition, an epidural catheter may be used in the postoperative period to provide analgesia.
A 58-year-old man with advanced-stage pancreatic cancer is requesting evaluation in the pain clinic for palliation. Which of the following is INCORRECT? A. The celiac plexus contains afferent and efferent fibers from T5-T12 roots. B. The plexus is blocked just anterior to the T8 vertebral body. C. The celiac plexus innervates most of the abdominal viscera. D. A celiac plexus block perioperatively can decrease body stress and endocrine response to surgery. E. Complications include aspiration of blood, urine, or CSF from the needle.
ANSWER: B T he celiac plexus contains fibers from T5-12 and has no somatic fibers. A celiac plexus block is performed at the L1 level just anterior to the L1 vertebral body and leads to autonomic blockade, leading to decreased stress and endocrine response to surgery. The plexus innervates most of the abdominal visceral organs. Its side effects/ complications include diarrhea, hypotension, inadvertent injection into the intrathecal and epidural space, as well as puncture of kidneys, ureters, aorta, vena cava, and bowel.
A patient with a normal dead-space-to-tidal-volume ratio ( V D / V T) of 30% is breathing 12 times per minute with a tidal volume of 500 mL. The patient then suffers a pulmonary embolism with the resultant increase of V D / V T to 50%. To maintain constant alveolar ventilation, the patient will: A. Decrease tidal volume to 340 mL B Increase respiratory frequency to 16 breaths per minute C . Decrease respiratory frequency to 8 breaths per minute D. Maintain current tidal volume E . Maintain current respiratory frequency
ANSWER: B The patient's minute ventilation ( V T ) can be calculated, 500 mL × 12 breaths/min = 6 L/min. Dead space ( V D ) can then be calculated, V T × ( V D / V T ) ; thus, 6 L/min × 30% = 1.8 L. Alveolar ventilation is determined by subtracting dead space from tidal volume . V T of 6 L/min minus V D of 1.8 L yields alveolar ventilation of 4.2 L/min. Pulmonary embolism increases physiologic dead space because the alveoli affected by the embolism will continue to be ventilated but not perfused. Th is decreases the number of lung units participating in gas exchange, thus increasing dead space and the V D / V T. To maintain an alveolar ventilation of approximately 4 L/min the patient would need to maintain a minute ventilation of 8 L/min [alveolar ventilation (4 L/min) = V T (8 L/min) - 0.5 × V T (8 L/min)]. Th e other answer choices would decrease or not change minute ventilation, making them incorrect choices.
Which of the following will increase the P 50 of hemoglobin? A. Decreased 2,3-DPG B. Decreased temperature C. Decreased pH D . Increased concentration of fetal hemoglobin. E. Decreased concentration of adult hemoglobin.
ANSWER: C The P 50 represents the partial pressure at which hemoglobin is 50% saturated with oxygen. When the oxygen dissociation curve shift s to the right, the P 50 increases. A decrease in the pH will shift the oxygen dissociation curve to the right and therefore increase the P 50. Increasing the concentration of fetal hemoglobin will shift the oxygen dissociation curve to the left because fetal hemoglobin has greater affinity for oxygen than adult hemoglobin.
For a chronic respiratory acidosis an increase in Pacó of 30 mm Hg will result in a decrease in pH of A. 0.06 units B. 0.08 units C. 0.09 units D. 0.16 units E. 0.24 units
ANSWER: C In chronic respiratory acidosis the pH will change 0.03 units for every 10-mm Hg change in Pacó . This is in contrast to acute respiratory acidosis, in which the pH will change 0.08 units for every 10-mm Hg change in Pacó . The ability of the kidneys to compensate for chronic respiratory acidosis by excreting acids and retaining filtered bicarbonate accounts for this difference between acute and chronic respiratory conditions.
Anatomic dead space begins at the mouth and/or nose and ends at the: A. Lobar bronchi B . Respiratory bronchioles C . Terminal bronchioles D. Alveolar ducts E . Alveolar sacs
ANSWER: C Conducting airways do not participate in gas exchange because they contain no alveoli. Th e conducting airways begin at the mouth and/or nose and end at the end of the terminal bronchioles. Respiratory bronchioles do participate in gas exchange.
Which of the following statements is TRUE regarding diff erential nerve sensitivity to local anesthetics? A. Small nonmyelinated C fibers are most susceptible to local anesthetic blockade. B. Large myelinated A α and A β are most susceptible to local anesthetic blockade. C. Small myelinated B fibers are most susceptible to local anesthetic blockade. D. Fibers carrying proprioception are more susceptible than fibers carrying cold sensation. E. Small nerve fibers are more susceptible than larger fibers.
ANSWER: C Different fibers have different susceptibility to local anesthetic blockade. Small myelinated B fi bers are most susceptible, followed by small myelinated axons A γ (motor) and A δ (sensory). Next are large myelinated axons A α (efferent to muscles) and A β (proprioception), and finally the least susceptible are the small nonmyelinated C fi bers. Th e thought that local anesthetics block the smallest fibers first is incorrect.
Distribution of ventilation in the lung in a spontaneously breathing patient is: A. Greatest at the apex B Greatest in the mid-lung zone C Greatest at the base D. Greatest in the upper two-thirds of the lung E. Evenly distributed
ANSWER: C Distribution of ventilation is not even throughout the lung. Alveoli at the base receive a larger percentage of ventilation. At functional residual capacity, the basal alveoli are on the steeper portion of the pressure-volume curve and are therefore more compliant than apical segments because these alveoli are smaller due to larger (less negative) pleural pressures at the base. Therefore, they receive a larger volume for a given change in pressure
Which is the site of greatest airway resistance? A. Trachea B . Largest bronchi C . Medium-sized bronchi D. Small bronchi E. Alveoli
ANSWER: C In the normal lung most of the resistance to airfl ow occurs in the first eight airway generations, with the greatest resistance at the medium-sized bronchi.
All of the following can be measured with a spirometer EXCEPT A. Vital capacity B. Tidal volume C Functional residual capacity D. Inspiratory capacity E . Forced expiratory volume in 1 second (FEV 1 )
ANSWER: C Spirometry is unable to measure functional residual capacity (FRC), residual volume (RV), and total lung capacity (TLC). FRC may be measured using the inert gas dilution technique or body plethysmography. FRC is the volume of gas in the lung at the end of quiet expiration and is normally 35 mL/kg or approximately 2.5 L in adult men. FRC is composed of expiratory reserve volume (ERV) and RV. Induction of anesthesia and placement of an endotracheal tube is associated with a decrease in FRC of approximately 450 mL, or 15% to 20%. Th is decrease in FRC will promote atelectasis and hypoxemia if FRC decreases below closing capacity.
In individuals with normal lungs, residual volume is determined by: A . Outward force generated by inspiratory muscles equal to inward recoil of the chest wall B . Inward force generated by inspiratory muscles equal to outward recoil of the chest wall C . Inward force generated by expiratory muscles equal to outward recoil of the chest wall D . Outward force generated by expiratory muscles greater than inward recoil of the chest wall E. Inward force generated by inspiratory muscles greater than outward recoil of the chest wall
ANSWER: C Th e residual volume in young healthy lungs is reached when two competing forces are equal to one another. Th is occurs when the inward force generated by the muscles of expiration equals the outward recoil of the chest wall when residual volume is reached.
All of the following nerves at the ankle are terminal branches of the sciatic nerve EXCEPT A. Posterior tibial nerve B . Sural nerve C. Saphenous nerve D. Deep peroneal nerve E. Superfi cial peroneal nerve
ANSWER: C Th e saphenous nerve is a terminal branch of the femoral nerve. All the other nerves listed are terminal branches of the sciatic nerve.
Which of the following statements is TRUE regarding cervical plexus block? A. Phrenic nerve blockade is a rare complication of deep cervical plexus block. B. Th e superficial cervical plexus innervates the sternocleidomastoid muscle. C. A deep cervical plexus block is performed at the C4, C5, and C6 levels. D. A superficial cervical plexus block is performed at the anteromedial aspect of the sternocleidomastoid muscle. E. Th e only major blood vessels at risk during a deep cervical plexus block are the carotid artery and the jugular vein, and both can easily be avoided.
ANSWER: C The cervical plexus is made up of C4-6 nerve roots. A superficial cervical plexus block only aff ects sensory nerves and is done posterior to the sternocleidomastoid muscle. A deep cervical plexus block is done at the transverse processes of C4, 5, and 6 and frequently leads to phrenic nerve paralysis (C3-5) as well as paralysis of other muscles in the neck, including the sternocleidomastoid. Vertebral artery injection is a major vascular complication that may occur during the deep cervical plexus block; it may lead to CNS depression, seizures, and stroke. Spinal and epidural injections are also possible.
Which of the following factors would promote a change from turbulent to laminar airflow in a straight tube? A. Increasing average velocity of gas fl ow B. Increasing the radius of the tube C. Decreasing the density of the gas D . Decreasing the viscosity of the gas E. Independent of the Reynolds number
ANSWER: C The nature of gas fl ow through a straight cylinder can be determined using the Reynolds number (R e ). When the Reynolds number is less than 2,000, fl ow is predominantly laminar, whereas when the Reynolds number is greater than 4,000, fl ow is turbulent. Between R e 2,000 and 4,000, both types of flow exist. es of flow exist. The Reynolds number is a dimensionless value and can be calculated: R = 2rvd/n, w here r is the radius of the cylinder, v is the average velocity, d is density of the gas, and n is the viscosity of the gas. Therefore, R e will be lower with decreasing the density of the gas, which would promote a change to laminar flow. The density of helium is the lowest of any gas except hydrogen, which is why it may be used in combination with oxygen, as Heliox, to treat upper airway obstruction or stridor.
Which of the following remains in the lung after a tidal volume breath is expired? A . Expiratory reserve volume B . Residual volume C . Functional residual capacity D. Inspiratory capacity E . Total lung capacity
ANSWER: C The remaining lung volume aft er a tidal volume breath is the functional residual capacity, which is the expiratory reserve volume plus the residual volume.
ll of the following nerves at the ankle are terminal branches of the sciatic nerve EXCEPT A. Posterior tibial nerve B . Sural nerve C. Saphenous nerve D. Deep peroneal nerve E. Superficial peroneal nerve
ANSWER: C The saphenous nerve is a terminal branch of the femoral nerve. All the other nerves listed are terminal branches of the sciatic nerve.
Which of the following statements regarding the cardiotoxicity of lidocaine is INCORRECT? A. Lidocaine has a negative inotropic action on cardiac muscle in a dose-dependent fashion. B. Lidocaine has antiarrhythmic properties while bupivacaine exhibits arrhythmogenic properties. C. Bupivacaine depresses rapid depolarization in Purkinje fibers but lidocaine speeds up rapid depolarization. D . High local anesthetic concentrations can lead to an increased PR interval and width of the QRS complex. E. Lidocaine cardiac toxicity may be observed in cases involving tumescent anesthesia
ANSWER: C Both lidocaine and bupivacaine depress rapid depolarization in Purkinje fi bers; however, lidocaine depresses the depolarization to a lesser extent and has a more rapid rate of recovery. Th ese eff ects lead to pro- versus anti-arrhythmic properties of lidocaine and bupivacaine. All local anesthetics have a dose-dependent negative inotropic effect on cardiac myocytes and lead to prolonged conduction time, leading to an increased PR interval and widened QRS. Large doses of dilute lidocaine used in tumescent anesthesia (35 to 55 mg/kg) may lead to cardiac toxicity and death
Vital capacity consists of: A . Functional residual capacity + inspiratory capacity B . Expiratory reserve volume + inspiratory reserve volume C . Expiratory reserve volume + inspiratory capacity D. Tidal volume + inspiratory reserve volume E . Functional residual capacity + expiratory reserve volume
ANSWER: C Vital capacity is the volume expired after a maximal inspiration followed by maximal expiration. Vital capacity comprises inspiratory capacity, which is the volume of maximal inspiration (tidal volume plus inspiratory reserve volume), and expiratory reserve volume, which is the volume of maximal expiration.
Which of the following airway types contributes LEAST to overall airway resistance? A . Large airways (>2 mm in diameter, first eight airway generations) B . Medium-sized airways (lobar and segmental) C. Medium-sized airways (subsegmental bronchi) D. Small airways (bronchioles, <2 mm in diameter) E. All contribute equally.
ANSWER: D Small airways with a diameter of less than 2 mm contribute to approximately 20% of the total airway resistance. This apparent paradox is explained by the large number of small airways. At each new generation of airway branching the radius of the airway decreases, which increases the resistance. However, at each airway branching there is an exponential increase in the number of small airways that exist in parallel. Resistance in an individual airway can be quantified using Poiseuille's law :
Please fill in the gaps. Oxygen is primarily transported in the blood ______, while carbon dioxide is primarily transported_____. A. Dissolved in plasma; chemically bound to amino acids B. Bound to hemoglobin; dissolved C . Dissolved in plasma; as bicarbonate ions D. Bound to hemoglobin; as bicarbonate ions E. Bound to hemoglobin; chemically bound to amino acids
ANSWER: D The primary means of transporting oxygen is bound to hemoglobin with a minimal contribution made by dissolved oxygen. The presence of hemoglobin increases the oxygen carrying capacity of the blood by about 65-fold. Carbon dioxide is transported either physically dissolved, chemically bound to amino acids, or as bicarbonate ions, with the major contribution coming from the bicarbonate ions. When carbon dioxide diffuses from the tissue into plasma it quickly dissolves and then again diff uses from the plasma into red blood cells, establishing an equilibrium. In red blood cells carbon dioxide is quickly converted to bicarbonate ions via a reaction catalyzed by carbonic anhydrase and the bicarbonate ions diff use out of the cell in exchange for chloride ions.
You are 3 hours into an aorto-bifemoral bypass with an estimated blood loss of 2 L and your current fluid administration is 6 L of normal saline. Currently the blood pressure is 90/45 mm Hg, pulse is 95 bpm, and central venous pressure is 4 cm H 2 O. Appropriate choices for fl uid administration include all the following EXCEPT A . Albumin, because you wish to avoid fluid overload with crystalloid B. Ringer's lactated solution, as you are worried about hyperchloremic metabolic acidosis with normal saline C. Any crystalloid, as there is no mortality difference between crystalloid and colloids D . Administration of crystalloid and blood products to a central venous pressure of 16 and a SVO 2 of 90% E. Packed red blood cells, if the hemoglobin is 7 g/dL
ANSWER: D Although there is a growing movement toward intraoperative goal-directed therapy, as in septic shock, more studies are needed to determine benefi t. While the insertion of a pulmonary artery catheter to measure mixed venous oxygen saturation and fl uid status is reasonable, resuscitation to predefi ned supernormal values confers no benefi t and may actually be detrimental to the patient. Th e choice of crystalloid versus colloid administration for fl uid resuscitation continues to remain controversial. Extrapolating data from the intensive care unit to the operating room and vice versa can confuse the picture even more. Most large studies, like the SAFE trial, and meta-analyses, like the Cochrane database, suggest that there is no mortality diff erence in crystalloids versus colloids. Th us, most would choose crystalloids due to the signifi cantly increased expense of colloids. Nevertheless, if the patient is better served with less fluid intake due to other comorbid conditions, colloids may be a reasonable choice, with the understanding that mortality is unlikely diff erent. Hyperchloremic metabolic acidosis can occur in large-volume fl uid resuscitation with normal saline; however, it is uncertain whether its occurrence aff ects clinical outcomes. Switching to Ringer's lactate with less sodium and chloride would be a reasonable choice. Blood would be an appropriate choice for a patient who is anemic and hypotensive with ongoing blood losses.
All of the following are true pertaining to fevers associated with transfusion of blood products EXCEPT: A . It may represent a hemolytic transfusion reaction. B . It may represent bacterial contamination. C. It may be due to cytokines or antibodies to donor leukocytes. D . Routine pre-medication can decrease the incidence of fevers. E. Stopping transfusion is prudent in the absence of hypotension.
ANSWER: D Fever during transfusion should be investigated. It can be relatively abrupt, suggesting a more sinister cause such as an acute hemolytic transfusion reaction or bacterial contamination. Febrile non-hemolytic transfusion reactions (FNHTRs), generally a diagnosis of exclusion, may be another cause. Stopping the transfusion for further investias continued transfusion may lead to less desirable situations, including hypotension and shock. Th e ASA Committee on Transfusion Medicine recommends stopping transfusions in patients who have a 1 °C or greater temperature rise not explained by the patient's condition (e.g., sepsis). It is no longer recommended that patients routinely receive acetaminophen and diphenhydramine as premedication to treat allergic or febrile nonhemolytic transfusion reactions. It is estimated that routine premedication would need to be done 200 times to prevent one reaction, at the same time increasing the costs and risk of drug side eff ects. Furthermore, it may delay action if fevers caused by acute hemolytic transfusion reactions are suppressed.
Which of the following cardiopulmonary changes is NOT TRUE of a T8 epidural level produced by a local anesthetic-only epidural solution? A. Decreased stroke volume and cardiac output B. Decreased mean arterial pressure C. Decreased peripheral vascular resistance D. Decreased resting minute ventilation E. Unchanged dead space
ANSWER: D Mid-thoracic-level epidural anesthesia with local anestheticonly solution leads to decreased stroke volume, cardiac output, mean arterial pressure, and peripheral vascular resistance. If the solution contains epinephrine as well as local anesthetic, stroke volume and cardiac output both increase; however, the drop in peripheral vascular resistance and mean arterial pressure is more dramatic. A mid-thoraciclevel epidural block produces no change in lung volumes, resting minute ventilation, dead space, or shunt fraction
Which of the following could cause a prolonged partial thromboplastin time (PTT) but not prothrombin time (PT)? A . Warfarin treatment B. Thrombocytopenia C . Disseminated intravascular coagulation (DIC) D . Von Willebrand disease E . Factor V deficiency
ANSWER: D Prothrombin time (PT) measures the extrinsic and fi nal common pathways of the coagulation cascade. Th e PT, which is normally 11 to 14 seconds (depending on the control), measures the activity of fi brinogen, prothrombin, and factors V, VII, and X. Th e relatively short half-life of factor VII (4 to 6 hours) makes the PT useful in evaluating hepatic synthetic function of patients with acute or chronic liver disease. Partial thromboplastin time (PTT) evaluates the intrinsic and common coagulation pathways and adequacy of all coagulation factors except XIII and VII. PTT is usually abnormal if any factor level drops below 25% to 40% of normal, depending on the PTT reagent used. PTT is commonly used to monitor heparin therapy. PTT is increased in defi ciency of any individual coagulation factor except XIII and VII, presence of nonspecifi c inhibitor (e.g., lupus anticoagulant), specifi c factor inhibitor, von Willebrand disease (PTT may also be normal), hemophilia A and B, DIC, heparin, direct thrombin inhibitor (e.g., hirudin, argatroban), and warfarin. W arfarin measurement is likely the most common indication for measurement of PT. It is usually reported in conjunction with the International Normalized Ratio (INR), which provides a standardized measurement of PT across diff erent laboratories. Factor VII aff ects the PT the most. In the perioperative setting, the prolonged PT oft en is caused by poor or restricted nutritional intake and/or antibiotic treatment causing a defi ciency in vitamin K (factors II, VII, IX, and X are vitamin K-dependent). Besides factor defi ciency, other causes include the presence of an inhibitor, liver disease (low factor V), amyloidosis (factor X defi ciency), and myeloproliferative disease (factor V defi ciency). Classically DIC leads to an increased PT, PTT, and fi brin degradation products as well as decreased platelets and fibrinogen
Thirty minutes after being transfused, your patient in the intensive care unit experiences a drop in blood pressure to 70/30 mm Hg. There is no hematuria or obvious source of bleeding. You are concerned about a transfusion reaction. The last known hemoglobin is 7 mg/dL. Your first action would be which of the following? A. Start an epinephrine infusion. B. Transfuse 1 unit of O-negative blood. C . Give a bolus of 1 mg epinephrine IV. D. Quickly infuse 1 L of crystalloid. E . Give 100 mg of hydrocortisone.
ANSWER: D Th is patient likely has an anaphylactic or anaphylactoid transfusion reaction . The first step is to stop the blood transfusion. The second step is to support and treat the patient. Whether or not this is an anaphylactic or anaphylactoid reaction, quickly administering fluids such as crystalloid often stabilizes the situation. Although epinephrine is the treatment for an anaphylactic or anaphylactoid reaction, small initial doses such as 0.3 to 0.5 mL of epinephrine 1:1,000 (300 to 500 mcg) subcutaneously or 5- to 10-mcg IV increments should be administered before escalating to the ACLS dose of 1 mg IV. The same is true for starting an epinephrine infusion, because volume expansion can be performed more quickly than starting an infusion. Despite a low hemoglobin and hypotension, transfusion of blood is unwarranted unless you think this patient is actively bleeding rather than having a transfusion reaction. Giving O-negative blood may worsen the picture and may muddle the investigation as to what happened. While hydrocortisone may be beneficial in treating an anaphylactic or anaphylactoid-type reaction, its benefits will not be realized for several hours.
According to the Bohr effect, the affinity of hemoglobin for oxygen is INCREASED with: A. Increased temperature B. Increased 2,3-DPG C. Decreased 2,3-DPG D. Decreased P co 2 E. Decreased pH
ANSWER: D The Bohr effect refers to changes in hemoglobin's affinity for oxygen with changes in P có and pH. Th e affinity of hemoglobin for oxygen increases with a decrease in Pcó and/or an increase in pH. Th is effect enhances oxygen uptake in the lung and the reverse enhances oxygen delivery in the tissues.
The P 50 for normal adult hemoglobin is: A. 5 mm Hg B. 15 mm Hg C. 20 mm Hg D. 27 mm Hg E. 35 mm Hg
ANSWER: D The P 50 is the partial pressure at which hemoglobin is 50% saturated with oxygen. For normal adult hemoglobin the P50 is 27 mm Hg. As the hemoglobin dissociation curve shift s to the right in response to increasing temperature, increasing Pcó, increasing 2,3-DPG, or decreasing pH, the P 50 increases. As the hemoglobin dissociation curve shift s to the left (hypothermia, alkalosis, decreasing 2,3-DPG), the P 50 decrease
Th e following muscles of respiration are used for inspiration EXCEPT A. Diaphragm B. Scalene muscles C. External intercostal D. Internal intercostal E. Sternocleidomastoid
ANSWER: D The forces generated by the muscles of inspiration are needed to inflate the lung. These muscles principally include the diaphragm and the external intercostal muscles, which pull the ribs up and forward during inspiration. Accessory muscles of respiration, including the scalene muscles and the alae nasi, which elevate the sternocleidomastoid and cause nasal flaring respectively, help with respiratory efforts during exercise or significant airway obstruction. The pharyngeal muscles, the genioglossus, and the arytenoid muscles help maintain upper airway patency and are included as muscles of inspiration. Expiration, on the other hand, is passive during normal quiet breathing but becomes active with exercise. The muscles of the abdominal wall, including the internal and external obliques, transversus abdominis, and rectus abdominis, are used during active expiration in conjunction with the internal intercostal muscles, which pull the ribs down and inward.
All of the following are TRUE regarding an epidural test dose EXCEPT A. Hemodynamic changes that occur after an epinephrine-containing test dose solution lead to decreased uteroplacental perfusion in an obstetric patient. B. Injection of 15 mcg of epinephrine should yield a 15- to 20-bpm rise in heart rate if the catheter is intravascular. C. Injection of 1 mL of air and hearing a mill-wheel murmur over the right heart with a Doppler is an appropriate test for intravascular injection. D. Aspiration from a single-orifice catheter is more sensitive in detecting an intravascular epidural catheter compared to a multi-orifice catheter. E. Injection of lidocaine 100 mg without epinephrine is an appropriate test dose to detect intravascular and/ or intrathecal catheter placement.
ANSWER: D The most commonly used test dose is perhaps the lidocaine solution containing epinephrine. Injection of 15 mcg of epinephrine will oft en lead to a rise in heart rate by 15 to 20 bpm. In the obstetric patient, the pain from uterine contractions may lead to an increase in heart rate and false positive test results. Also, injection of epinephrine, if the catheter is indeed intravascular, will lead to decreased uteroplacental perfusion; however, these changes in perfusion are transient and perhaps of less duration compared to the decreased perfusion from uterine contractions. Injection of 1 mL of air and using a Doppler to listen for mill-wheel murmur over the right heart is an appropriate test for detecting an intravascular catheter. A multi-orifi ce catheter is 98% sensitive in identifying intravascular location. With a single-orifi ce catheter, aspiration reportedly fails to detect 34% to 81% of intravascular catheters. A lidocaine 100 mg injection without epinephrine is a large enough dose to produce dizziness, tinnitus, and perioral numbness if the catheter is intravascular, and an intrathecal catheter should produce a profound spinal anesthesia and is considered an appropriate test dose. The same is true for 25 mg of bupivacaine without epinephrine. The goal is to inject a subtoxic dose of a local anesthetic to cause symptoms with intravascular and intrathecal injections without causing systemic toxicity or a total spinal.
During your aorto-bifemoral bypass graft case, you give the patient 3 L of crystalloid, 1 unit of packed red blood cells, and 500 mL of 5% albumin. Estimated blood loss is 2 L. The patient's vital signs are blood pressure 85/40 mm Hg, heart rate 105, and oxygen saturation 85%. Ventilation requirements are increasing with worsening hypoxia. Current ventilator settings are tidal volume 600 mL, rate 14, FiÓ 1.0, and PEEP +8. Your blood gas analysis reveals a pH of 7.35, Pac ó 35, Pao 2 50, and oxygen saturation of 85%. You suspect this may be transfusion-related acute lung injury (TRALI) and decide not to extubate. What would be the best way to confirm this diagnosis? A. Leukopenia B. Obtaining a chest x-ray C. Inserting a pulmonary artery catheter to obtain PA pressures D. Sending a specimen to the blood bank for an antibody-antigen cross-match E. This is not TRALI.
ANSWER: D Transfusion-related acute lung injury (TRALI) is defined as an acute lung injury within 6 hours of transfusion with features of hypoxemia (with a Pa ó /FiO 2 < 300 mm Hg), bilateral pulmonary infi ltrates on chest radiograph, and lack of left atrial hypertension. It has been previously described as pulmonary hypersensitivity reaction and noncardiogenic pulmonary edema. Its reported incidence is 1 in 5,000 transfusions, but the actual incidence is unknown because of under-reporting and difficulty in distinguishing it from transfusion-associated circulatory overload (TACO). A "two-hit" hypothesis has been proposed for the etiology of TRALI, with comorbidities such as hematologic malignancies, cardiopulmonary bypass exposure, burns, sepsis, trauma, and massive transfusions being the initial "hit." Th e second insult is likely immunogenic, where passively transfused antibodies, biologic active lipids, or plasma breakdown products activate neutrophils that lead to oxidative and nonoxidative destruction of the pulmonary endothelium, causing pulmonary edema. TRALI can be induced in patients receiving as little as 10 to 15 mL of plasma. It is also more likely in patients who receive platelets compared to fresh frozen plasma and packed red blood cells. Treatment is generally supportive, with the use of lung-protective ventilation strategies and fluid minimization. Leukopenia is oft en seen, and fever is oft en associated with TRALI; however, its presence is oft en missed and is nonspecific by itself. Likewise, a chest x-ray is important in the diagnosis of TRALI, but it cannot distinguish it from other causes of hypoxemia, such as TACO and heart failure. Th e insertion of a pulmonary artery catheter to measure the pulmonary arterial occlusion pressure, not the pulmonary artery pressure, would be helpful in ruling out left atrial hypertension (where PAOP ≥ 18 mm Hg), and thus a cardiac etiology for the pulmonary insufficiency. Sending a patient specimen back to the blood bank for an antibody-antigen cross-match, especially to identify granulocyte and HLA donor antibodies, would be the best way to confi rm the diagnosis of TRALI. Nevertheless, TRALI is still a clinical diagnosis, and ruling out other cardiogenic and volume-induced pulmonary edema is important.
An axillary block is performed for a surgical procedure involving the hand. Which of the following is INCORRECT when evaluating the adequacy of the block for surgery? A. Median nerve block can be evaluated by testing the lateral aspect of the ring finger. B. Radial nerve block can be evaluated by testing the posterolateral aspect of the hand. C. Ulnar nerve block can be evaluated by testing the medial aspect of the ring finger. D. Median nerve block can be evaluated by testing the medial aspect of the palm. E. Radial nerve block can be evaluated by testing the lateral aspect of the dorsum of the hand.
ANSWER: D A median nerve block covers the palmar aspect of the thumb and index fi nger, the middle fi nger, and the lateral aspect of the ring fi nger, including the lateral palmar surface. The medial palmar surface as well as the medial aspect of the ring fi nger and the little finger is innervated by the ulnar nerve. Th e radial nerve innervates the lateral aspect of the dorsum of the hand and the proximal thumb and index and middle finger.
An axillary block is performed for a surgical procedure involving the hand. Which of the following is INCORRECT when evaluating the adequacy of the block for surgery? A. Median nerve block can be evaluated by testing the lateral aspect of the ring finger. B. Radial nerve block can be evaluated by testing the posterolateral aspect of the hand. C. Ulnar nerve block can be evaluated by testing the medial aspect of the ring finger. D. Median nerve block can be evaluated by testing the medial aspect of the palm. E. Radial nerve block can be evaluated by testing the lateral aspect of the dorsum of the hand.
ANSWER: D A median nerve block covers the palmar aspect of the thumb and index finger, the middle finger, and the lateral aspect of the ring finger, including the lateral palmar surface. The medial palmar surface as well as the medial aspect of the ring finger and the little finger is innervated by the ulnar nerve. Th e radial nerve innervates the lateral aspect of the dorsum of the hand and the proximal thumb and index and middle finger.
Which of the following factors affect dynamic compliance of the lung? A. Tidal volume B. Airway resistance C. Respiratory rate D .All of the above E. None of the above
ANSWER: D Dynamic compliance is the change in lung volume divided by the distending pressure measured during the course of breathing, as compared to static compliance, which is measured in a nonmobile lung. Dynamic compliance is very closely related to static compliance in normal individuals. However, there are three factors that will influence dynamic but not static compliance: tidal volume, airway resistance, and respiratory rate. At larger tidal volumes the larger change in alveolar surface area induces increased surfactant at the alveolar surface, which increases dynamic compliance compared to static compliance. Alveolar units with increased airway resistance require increased filling time in order to achieve the same volume compared to other alveolar units with the same compliance but less airway resistance. Th e alveolar units with increased resistance are referred to as having long time constants. As respiratory rate increases, the alveolar units with long time constants will have insufficient time to fill and will not participate in dynamic compliance. Therefore, as airway resistance and respiratory rate increase, dynamic compliance decreases compared to static compliance.
Which of the following therapies carries the least infectious risk? A. Whole blood B. Fresh frozen plasma C. Thawed plasma D. Platelets E. Albumin
ANSWER: E All blood products can carry infectious risks. Whole blood contains all the components of blood prior to separation. It is rarely used except on the battlefi eld or in the absence of a blood-banking system. Risks of disease transmission include bacterial, viral, parasitic, and prion diseases. Modern blood donation and banking practices, including screening and storage, have decreased much of the infectious transmission risks associated with blood products. Plasma, whether frozen or thawed, carries the same infectious risks. Platelets carry similar infectious risks. However, because they are stored at room temperature to optimize eff ectiveness for up to 5 days, platelets are also prone to increased bacterial contamination, including syphilis, compared to blood products stored at lower temperatures. A lbumin is pooled from a large human volunteer population and then undergoes pasteurization for 10 hours at 60 degrees C. Th is in vitro process essentially kills all enveloped and nonenveloped viruses, including HIV and hepatitis. Th ere have been reports that Creutzfeldt-Jakob disease, a prion disease, could be transmitted through albumin therapy. Albumin does not contain preservatives and is latex-free.
58-year-old woman with a recent diagnosis of endstage renal disease is scheduled for creation of an upperextremity fistula just proximal to the elbow. Her medical history includes insulin-dependent diabetes, hypertension, and a 80 pack-year history of smoking. Which of the following is TRUE? A. An axillary block would be the best option since it has least likelihood of complications, including pneumothorax. B. An interscalene block would be best to cover all sensory nerves to the upper arm, including the intercostobrachial nerve. C. A supraclavicular block is performed at the level of the cords and can effectively block the brachial plexus for the upper arm. D. An infraclavicular block is performed at the distal trunks and can be used to provide adequate sensory block for the surgery. E. The surgery can be performed with sedation and local infiltration of anesthesia provided by the surgeon
ANSWER: E An axillary block is not suitable for surgery of the upper arm. An interscalene block is performed at the level of the trunks and is the most proximal block of the brachial plexus, which is derived from C5-T1 nerve roots. The intercostobrachial nerve innervates the medial aspect of the upper arm and is derived from T2, and hence is not blocked with any brachial plexus block. A supraclavicular block is performed at the level of distal trunks/proximal divisions and NOT at the level of the cords. An infraclavicular block is performed at the level of the cords and NOT the trunks. Surgery for this patient can be performed by sedation and local infi ltration by the surgeon. Interscalene, supraclavicular, and infraclavicular blocks could all provide adequate analgesia for this procedure as well.
A 58-year-old woman with a recent diagnosis of endstage renal disease is scheduled for creation of an upperextremity fistula just proximal to the elbow. Her medical history includes insulin-dependent diabetes, hypertension, and a 80 pack-year history of smoking. Which of the following is TRUE? A. An axillary block would be the best option since it has least likelihood of complications, including pneumothorax. B. An interscalene block would be best to cover all sensory nerves to the upper arm, including the i ntercostobrachial nerve. C. A supraclavicular block is performed at the level of the cords and can effectively block the brachial plexus for the upper arm. D. An infraclavicular block is performed at the distal trunks and can be used to provide adequate sensory block for the surgery. E. Th e surgery can be performed with sedation and local infiltration of anesthesia provided by the surgeon
ANSWER: E An axillary block is not suitable for surgery of the upper arm. An interscalene block is performed at the level of the trunks and is the most proximal block of the brachial plexus, which is derived from C5-T1 nerve roots. The intercostobrachial nerve innervates the medial aspect of the upper arm and is derived from T2, and hence is not blocked with any brachial plexus block. A supraclavicular block is performed at the level of distal trunks/proximal divisions and NOT at the level of the cords. An infraclavicular block is performed at the level of the cords and NOT the trunks. Surgery for this patient can be performed by sedation and local infiltration by the surgeon. Interscalene, supraclavicular, and infraclavicular blocks could all provide adequate analgesia for this procedure as well
.The surgeon asks you to administer Dextran 40 to a patient undergoing carotid endarterectomy. What is the purpose of this? A . Increase intravascular volume B. Serve as an anti-inflammatory C. Affect glucose hemostasis D . Induce hypertension to maintain cerebral perfusion pressure E. Act as an anticoagulant
ANSWER: E Dextran is a branched-chain polysaccharide of varying chains used medicinally as an antithrombotic or a volume expander. It comes in two formulations, Dextran 40 and 70, based on its molecular weight. Although both formulations can be used as volume expanders, Dextran 40 is more commonly used in vascular and microvascular surgery because of its interaction with platelets, factor VIII, and endothelial cells to decrease platelet aggregation and blood viscosity. These perceived benefits are hypothesized to aid in maintaining graft patency and microcirculation, although its popularity and effectiveness have been questioned. The benefits of increased intravascular volume and induced hypertension are probably not realized at low infusion rates, usually between 30 and 50 mL/hr. Dextran 40 is not related to dexamethasone, a steroid, which has anti-infl ammatory properties, nor should it affect glucose control despite its sugar backbone.
Epidural blockade with 0.25% bupivacaine at mid- to high thoracic levels would be expected to: A . Reduce minute ventilation B. Increase the respiratory rate C. Increase the work of breathing D. Lower P a O 2 E . Reduce expiratory reserve volume
ANSWER: E Even with a high thoracic epidural block, lung volumes (tidal volume, vital capacity) and resting minute ventilation are mostly unchanged. In patients dependent on accessory muscle function to maintain adequate ventilation, a thoracic epidural could affect forced expiratory maneuvers. However, in a study by Gruber et al. involving patients with end-stage chronic obstructive pulmonary disease undergoing lung-volume-reduction surgery, thoracic epidural analgesia (T2-T8) with 0.25% bupivacaine did not adversely aff ect minute ventilation, tidal volume, respiratory rate, P a O 2 , P aC O 2 , peak inspiratory and expiratory f ow rates, and work of breathing. Historically, high spinal and epidural blockade have been shown to lead to reductions in
A 56-year-old man is receiving epidural analgesia aft er a laparotomy and resection of a pancreatic lesion. Which of the following is TRUE regarding the use of opiates in the epidural solution? A. Use of opiates in the epidural solution leads to a higher incidence of respiratory depression compared to a patient-controlled intravenous administration of opiates. B. Both fentanyl and hydromorphone infusion in equipotent doses provide the same analgesic potency in a lumbar epidural for this patient. C. Th e analgesic site of action for continuous infusion of a hydrophilic opioid is systemic. D. A bolus of hydrophilic opiate will provide a more rapid onset of analgesia than a bolus of a lipophilic opiate. E. A single bolus of fentanyl 100 mcg in the epidural space is an appropriate step in treating breakthrough pain in this patient.
ANSWER: E Neuraxial opiates lead to respiratory depression in a dosedependent manner; however, the incidence of respiratory depression is no more than with intravenous administration. Fentanyl and other lipophilic opiates provide less cephalad spread compared to hydromorphone and morphine and would be less useful in a lumbar epidural in this patient with a thoracic-level incision. Th e analgesic site of action for hydrophilic opiate infusions is primarily spinal. Th e analgesic site of action for lipophilic drugs depends on the mode of administration. It's been shown that epidural infusion of these drugs has primarily a systemic eff ect, while single boluses act primarily on the spine. A lipophilic opiate injection has a more rapid onset than a hydrophilic opiate in the epidural space; because of this, a single bolus of fentanyl 25 to 100 mcg is an appropriate step in treating breakthrough pain in this patient
22-year-old athlete is scheduled for an anterior cruciate ligament reconstruction in an ambulatory surgery center. He would like to avoid general anesthesia. Which of the following will lead to a most complete analgesia and speedy recovery and discharge? A. Spinal anesthesia with bupivacaine and morphine sulfate (Duramorph) B. Femoral and obturator nerve block C. Femoral and popliteal nerve block D. Fascia iliaca block E . Sciatic and femoral block
ANSWER: E Spinal anesthesia will lead to complete analgesia for the surgery; however, in the outpatient setting, bupivacaine may lead to prolonged difficulty with voiding. Also, Duramorph is reserved for inpatients, as there may be a delayed-onset (12-16 hours) respiratory depression. Femoral and obturator nerve blocks will cover the anteromedial aspect of the knee but not the posterior, which comes from the sciatic nerve. A nerve block in the popliteal fossa will likely not cover the pain. Th e sciatic nerve must be blocked more cephalad, above the bifurcation into the tibial nerve and the common peroneal nerve. A fascia iliaca block will also miss the posterior aspect of the knee.
What is the approximate oxygen content in blood if the blood gas study reveals a Páo of 95 mm Hg with a hemoglobin concentration of 10 g/dL and an oxygen saturation of 98%? A. 0.3 mL O 2 /dL blood B. 1.0 mL O 2 /dL blood C. 1.3 mL O 2 /dL blood D. 10 mL O 2 /dL blood E. 13 ml O 2 /dL blood
ANSWER: E Th e oxygen content in blood is the volume of oxygen contained per unit volume of blood. Oxygen is carried in the blood bound to hemoglobin, and as dissolved oxygen. Th e total oxygen content in blood is the sum of the bound oxygen and the dissolved oxygen. Th e oxygen bound to hemoglobin can be calculated because the oxygen-binding capacity for hemoglobin is 1.34 mL of oxygen per gram of hemoglobin. Th erefore, oxygen bound to hemoglobin = (1.34 mL O 2 /g Hgb) (10 g Hgb/dL) (98 % saturation/100) = 13.1 mL O 2 /dL blood. Th e dissolved O 2 content can also be calculated by multiplying the Pao 2 by the solubility of oxygen, which is 0.00304 mL O 2 /dL blood. Dissolved O 2 content = 95 mm Hg × 0.00304 mL O 2 / dL blood) = 0.3 mL O 2 /dL blood. T otal oxygen content = oxygen bound by hemoglobin + dissolved oxygen. In this example, total oxygen content = 13.1 mL O 2 /dL + 0.3 mL O 2 /dL = 13.4 mL O 2 /dL blood.
Which of the following is LEAST likely to be the cause of excessive bilirubin levels from hemolysis of red blood cells in the perioperative period? A. G6PD defifciency B . Sickle cell disease C. Prosthetic cardiac valves D. Massive blood transfusion E. Kidney failure
ANSWER: E The liver usually clears bilirubin from the blood by conjugation, and thus in liver failure, not kidney failure, there is often an increased bilirubin load. All the other disease states (answers A, B, C) can cause hemolysis of red blood cells: metabolic (G6PD deficiency), structural (sickle cell disease), and mechanical (prosthetic valves). Approximately 10% to 25% of transfused red cells can hemolyze within 24 hours. Hence, massive transfusion can result in increased bilirubin levels.
Which of the following neurohumoral factors has the LEAST effect of increasing airway resistance? A. Acetylcholine B. Prostacycline C. Serotonin D. Thromboxane Á E. cAMP
ANSWER: E Airway resistance is regulated by neurohumoral agents and autonomic neural input via their effects on the smooth muscle surrounding the airway. Stimulation of the parasympathetic nervous system causes airway smooth muscle constriction. Various neurohumoral agents will also cause smooth muscle constriction, including histamine, acetylcholine, thromboxane A 2 , serotonin, prostacycline, and leukotrienes. Cyclic AMP has a direct bronchodilating effect.
With respect to bupivacaine toxicity, which of the following is TRUE? A. CNS stimulation is often followed by CNS depression via blockade of inhibitory pathways. B. Th e ratio of dose required to induce cardiovascular collapse(CC) to the dose required for CNS effects [CC/CNS] is higher for bupivacaine than for lidocaine. C . Succinylcholine administration to a patient with a tonic clonic seizure may contribute to metabolic acidosis. D. Hyperventilation may lead to more CNS toxicity. E. Combined metabolic and respiratory acidosis may further exacerbate CNS toxicity.
ANSWER: E Hypercapnia increases cerebral blood fl ow and allows more bupivacaine to be delivered to the brain. Combined respiratory and metabolic acidosis decreases plasma protein binding of bupivacaine, which leads to a higher concentration in the plasma, leading to further exacerbation of toxicity. CNS stimulation occurs fi rst as the inhibitory pathways are blocked fi rst, allowing uninhibited discharge of neurons in the cerebral cortex. Th is is followed by CNS depression as both inhibitory and excitatory neurons are inhibited. Th e CC/CNS ratio is lower for bupivacaine, meaning there is a smaller difference in doses required to cause CNS toxicity and cardiovascular toxicity. Th is smaller diff erence leads to a concern that CNS toxicity is not always detected prior to devastating cardiac toxicity. Tonic clonic seizures may lead to severe skeletal muscle contractions, leading to acidosis. Administration of succinylcholine will prevent this from occurring.
With respect to bupivacaine toxicity, which of the following is TRUE? A. CNS stimulation is often followed by CNS depression via blockade of inhibitory pathways. B. The ratio of dose required to induce cardiovascular collapse(CC) to the dose required for CNS effects [CC/CNS] is higher for bupivacaine than for lidocaine. C . Succinylcholine administration to a patient with a tonic clonic seizure may contribute to metabolic acidosis. D. Hyperventilation may lead to more CNS toxicity. E. Combined metabolic and respiratory acidosis may further exacerbate CNS toxicity.
ANSWER: E Hypercapnia increases cerebral blood flow and allows more bupivacaine to be delivered to the brain. Combined respiratory and metabolic acidosis decreases plasma protein binding of bupivacaine, which leads to a higher concentration in the plasma, leading to further exacerbation of toxicity. CNS stimulation occurs fi rst as the inhibitory pathways are blocked fi rst, allowing uninhibited discharge of neurons in the cerebral cortex. Th is is followed by CNS depression as both inhibitory and excitatory neurons are inhibited. Th e CC/CNS ratio is lower for bupivacaine, meaning there is a smaller diff erence in doses required to cause CNS toxicity and cardiovascular toxicity. Th is smaller diff erence leads to a concern that CNS toxicity is not always detected prior to devastating cardiac toxicity. Tonic clonic seizures may lead to severe skeletal muscle contractions, leading to acidosis. Administration of succinylcholine will prevent this from occurring.
All of following statements are TRUE regarding plica mediana dorsalis EXCEPT A. It is a midline connective tissue band visualized on epiduroscopy. B. It extends from the dura mater toward the ligamentum flavum. C. It may lead to difficult catheter insertion. D. It may lead to unilateral epidural block. E . It may lead to unilateral spinal block.
ANSWER: E P lica mediana dorsalis has been visualized in epiduroscopies and epidurographies, but its clinical signifi cance has been debated. When present, it extends from the dura mater toward the ligamentum fl avum, and thus it can cause problems with threading the catheter or lead to a unilateral block. It will not result in a unilateral spinal block since it does not extend beyond the dura and is not present in the intrathecal space. Again, it does not appear to have major clinical significance.
Please fill in the gaps. Surfactant _____ surface tension, ______ compliance of the lung, ______ work of breathing, and is produced by _______ in the lung. A. Decreases, increases, decreases, endothelial cells B. Increases, increases, decreases, type 2 alveolar e pithelial cells C. Decreases, decreases, decreases, type 1 alveolar e pithelial cells D. Increases, decreases, increases, type 1 alveolar e pithelial cells E. Decreases, increases, decreases, type 2 alveolar e pithelial cells
ANSWER: E Surfactant is a mixture of phospholipids, lipids, fatty acids, and proteins produced by type 2 alveolar epithelial cells. Surfactant decreases surface tension and increases compliance of the lung, thereby decreasing work of breathing.
Match the impact of physiological and or pharmacological factors on MAC. a. Increase MAC 1. gender b. No change in MAC 2. Red heads c. Decrease MAC 3. pregnancy 4. Chronic ETOH 5. BP > 40 mmHG 6. Alpha 2 agonist 7. hyperthermia 8. increase catecholamines 9. lidocaine 10. hypernatermia
ANSWERS A = 2,7,8,10 B= 1,4,5 C= 3,6,9 The minimal alveolar concentration can be affected by a multitude of factors that alter uptake, absorption, distribution, and elimination of the volatile anesthestic agent.
Organs with the capability of autoregulation, that is, maintenance of blood flow in spite of changes in perfusion pressure, include: (Choose all that apply) 1. Heart 2. Kidney 3. Brain 4. Liver
All (1-4) Autoregulation is the intrinsic ability of a vascular system to adjust its resistance to maintain blood flow constant over a wide range of mean arterial pressures. Arterial systems that are autoregulated include the cerebral, renal, coronary, hepatic arterial, and intestinal systems, and muscle circulation
Viral hepatitis is a possible risk with administration of which of the following? (Pick all that apply) I. Fresh frozen plasma 2. Cryoprecipitate 3. Platelets 4. Albumin
All blood products are routinely screened for hepatitis B and hepatitis C, but not hepatitis A. Except for albumin, each of the blood products listed in this question has the potential to be infective, although the risk is very small. Albumin is prepared by fractionating pooled human plasma. Albumin is also heat treated for 10 hours at 60°C, which appears to kill viruses.
Which of the following may indicate moderate to severe asthma (Choose 2) a. FEV1 80% of predicted value. b. FEV1 values less than 80% of predicted value c. FEV1/FVC ratios increased greater than 5% d. FEV1/FVC ratios normal e. FEV1/FVC ratios decreased 5%
B, E FEV1 values less than 80% of predicted value. FEV1/FVC ratios decreased 5%
An increase in intraocular pressure has been associated with: (select 3) A-nitrous oxide administration B-succinylcholine administration C-opioid administration D-hyperventilation E- laryngoscopy F- hypoxemia G-sevoflurane administration
B, E, F succinylcholine, laryngoscopy, hypoxemia. Succinylcholine increases intraocular pressure by 5 - 10 mm Hg for 5 - 10 minutes after administration. This increase is primarily the result of prolonged contracture of the extraocular muscles from the depolarizing effects of succinylcholine. Nitrous oxide, volatile anesthetic agents and opioids have been associated with a reduction in intraocular pressure. Hypoxemia, hypercarbia, hypertension, hypervolemia, laryngoscopy and intubation have all been shown to increase IOP.
Changes found in banked blood include: (Select 2) A- increased levels of 2,3-DPG B - a left shift of the hemoglobin dissociation curve C- decreased levels of potassium D- formation of microaggregates E- alkalosis secondary to the presence of citrate F- increased intracellular ATP stores G- thrombocytosis
B,D Changes occurring in banked blood include: Depletion of 2,3-DPG Depletion of intracellular ATP Oxidative damage Increased adhesion to vascular endothelium Altered cell morphology Accumulation of microaggregates Hyperkalemia (as high as 17.2 mEq/L) Absence of platelets (after 2 days of storage) Hemolysis Accumulation of proinflammatory products
What is the normal V/Q ratio? (A) 1 (B) 0.8 (C) 2 (D) 0.5
B- 0.8 Normally, ventilation (V) is approximately 4 L/min, whereas pulmonary blood ow (Q) is approximately 5 L/min. T ere ore, the ventilationper usion ratio (V/Q) or the whole lung is 0.8.
Intracranial hypertension is defined as a sustained increase in intracranial pressure (ICP) above: A- 5 mm Hg B- 15 mm Hg C- 25 mm Hg D- 30 mm Hg
B- 15 mm Hg Intracranial hypertension is defined as a sustained increase in intracranial pressure (ICP) above 15 mm Hg. Uncompensated increases in tissue or fluid within the rigid intracranial vault produce the sustained pressure elevations.
A 24-year-old female is scheduled for resection of a cerebral aneurysm. She has no other significant past medical history. Acceptable levels of hypotension would include a mean arterial pressure of: A- 20 - 30 mm Hg B- 35 - 45 mm Hg C-50 - 60 mm Hg D- 90 - 100 mm Hg
B- 35 - 45 mm Hg Healthy young individuals tolerate mean arterial pressures as low as 50 - 60 mm Hg without complications. Chronically hypertensive patients have altered autoregulation of cerebral blood flow and may tolerate a mean arterial pressure of no more than 20 - 30% below baseline.
Active cooling for a patient that is expericeing malignan hyperthermia, should be discontinued when the patient's tempertute drops below what? A- 37 degrees Celsius B- 38 degrees Celsius C- 39 degrees Celsius D- 40 degrees Celsius
B- 38 degrees Celsius
According to the Modified Glasgow Coma Scale, a moderate head injury is associated with a score of: A- 13 - 15 B- 9 - 12 C- 6 - 9 D- less than 6
B- 9 - 12 According to the Modified Glasgow Coma scale, mild head injury is associated with a score of 13 - 15, moderate head injury is associated with a score of 9 - 12, and severe head injury is associated with a score of less than 8.
In the figure below, inspiratory capacity is best represented by: A- A B- A + tidal volume C- B D- B + tidal volume
B- A + tidal volume Inspiratory capacity is the sum of the inspiratory reserve volume (A) and the tidal volume. B represents the expiratory reserve volume, C represents the FRC, D represents the residual volume, E represents the vital capacity and F represents the total lung volume.
Current anesthesia apparatus checkout recommendations suggest which of the following prior to every case? A-Check oxygen cylinder supply B-Check the carbon dioxide absorber C-Performance of a machine low-pressure leak test D-Calibration of the oxygen monitor
B- Check the carbon dioxide absorber Verification of the adequacy of the carbon dioxide absorber is suggested prior to every case. If the same anesthesia machine is being used by the same provider, E-cylinder pressure checks, machine low-pressure leak testing and calibration of the oxygen sensor need not be repeated after an initial check.
When compared to the trachea, which of the following is increased in the terminal bronchioles? A- Airflow velocity B- Cross sectional area. C- Quantity of goblet cells. D- Amount of cartilage.
B- Cross sectional area.
A 62 year old male with a history of small cell carcinoma presents for mediastinoscopy. He complains of muscular weakness that improves with exercise. This patient: (Select 2) A- Has a defect at the postsynaptic nicotinic receptor at the NMJ. B- Is sensitive to succinylchline. C- Is resistant to reversal with neostigmine. D-Should be worked up for thymoma.
B- Is sensitive to succinylchline. C- Is resistant to reversal with neostigmine. Patients with Eaton-Lambert syndrome has a defect at the presynaptic receptor at the NMJ (2 little ACH is released). These patients are sensitive to the effects o depolarizing and non-depolarizing blockers. Additionally, they are resistant to reversal with a anticholinersterase agent.
Which of the following agents are oxy-barbituates? (Select 2) A- Thyamylal B- Methohexital C- Thiopental D- Phenobarbital
B- Methohexital D- Phenobarbital Barbituates are divided into 2 groups oxybarbituates and thiobarbituates. oxybarbituates have oxygen at the 2nd position and they are methoxhexital, pheonbarbital and secobarbital. The oxygroup are thiobarbituates and have a sulfur at the 2nd position. They are thyamylal and thiopental.
The Bourdon pressure guage can be used to calculate the cylinder volume for which gases (Select 2) A- Carbon dioxide B- Nitrogen C- Nitrous oxide D- Helium
B- Nitrogen D- Helium Nitrous oxide and carbon dioxide exist as liquids inside the cylinder. Only after the gas that is not in the liquid phase will the pressure begin to decline.
Neuraxial anesthesia is MOST appropriate for which of the following patients? A- A 32-year-old woman patient receiving a recombinant hirudin derivative (desirudin, lepirudin) due to previous heparin induced thrombocytopenia. B- A 55-year-old woman undergoing total hip arthroplasty who is receiving aspirin 325mg bid. C- A 70-year-old man who had a drug-eluting stent placed 6-months ago and continues on clopidogrel therapy. D- A 75-year-old man who stopped coumadin 3 days ago and the INR is pending.
B- Nonsteroidal anti-inflammatory drugs seem to represent no added significant risk for the development of spinal hematoma in patients having epidural or spinal anesthesia. Nonsteroidal anti-inflammatory drugs (including aspirin) do not create a level of risk that will interfere with the performance of neuraxial blocks. Caution should be used when performing neuraxial techniques in patients recently discontinued from long-term warfarin therapy. In the first 1 to 3 days after discontinuation of warfarin therapy, the coagulation status (reflected primarily by factor II and X levels) may not be adequate for hemostasis despite a decrease in the INR (indicating a return of factor VII activity). Adequate levels of II, VII, IX, and X may not be present until the INR is within reference limits. We recommend that the anticoagulant therapy must be stopped (ideally 4-5 days before the planned procedure) and the INR must be normalized before initiation of neuraxial block. On the basis of labeling and surgical reviews, the suggested time interval between discontinuation of thienopyridine therapy and neuraxial blockade is 14 days for ticlopidine and 7 days for clopidogrel. Recombinant hirudin derivatives, including desirudin (Revasc), lepirudin (Refludan), and bivalirudin (Angiomax) inhibit both free and clot-bound thrombin. Argatroban (Acova), an l-arginine derivative, has a similar mechanism of action. These medications are indicated for the treatment and prevention of thrombosis in patients with heparin-induced thrombocytopenia and as an adjunct to angioplasty procedures. There is no "antidote"; the antithrombin effect cannot be reversed pharmacologically. Although there are no case reports of spinal hematoma related to neuraxial anesthesia among patients who have received a thrombin inhibitor, spontaneous intracranial bleeding has been reported.
Naloxone is least likely to reverse opioid depression caused by A- hydromorphone B- buprenorphine C- meperidine D- nalbuphine
B- buprenorphine Buprenorphine binds to the mu receptor with an affinity 50 times that of morphine. Additionally, buprenorphine is slow to dissociate from the mu receptor. For these reasons, buprenorphine is highly reistanstant to compretitive antagonism by naloxone.
The primary mechanism of intraoperative heat loss resulting in hypothermia is: A- convection B- radiation C- conduction D- evaporation
B- radiation Radiation accounts for approximately 40% of intraoperative heat loss. Convection is the next most significant mechanism of loss accounting for 32%.
How many colony-forming units are required from a quantitative bronchoalveolar lavage (BAL) to make the diagnosis of pneumonia? A-1,000 CFU/mL B-10,000 CFU/mL C-100,000 CFU/mL D-1,000,000 CFU/mL
B-10,000 CFU/mL The cutoff point used for the diagnosis of pneumonia is 10,000 CFU/mL for BAL (for endotracheal aspirates the cutoff is 1,000,000 CFU/mL, and for a protected brush specimen the cutoff is 1,000 CFU/mL). Diagnosing a pneumonia with less than 10,000 CFU/mL based on a BAL runs the risk of inappropriately administering antibiotics, and theoretically runs the risk of increased antimicrobial resistance.
A 56-year-old man is undergoing a right carotid endarterectomy with intraoperative EEG monitoring. Which of the following cerebral blood flow rates BEST defines the range where signs of ischemia first appear on EEG? A-< 15 mL/min/100 gm B-15-20 mL/min/100 gm C-25-30 mL/min/100 gm D-40-45 mL/min/100 gm
B-15-20 mL/min/100 gm EEG provides evidence of electrical activity to cortical surface cells, which is an area vulnerable to ischemia. Regional cerebral blood flow is 50-55 mL/min/100gm brain tissue and ischemia begins at 18-20 mL/min/100gm and thus EEG deterioration becomes evident in the range of 15-20 mL/min/100gm. EEG signs of ischemia include slowing of the EEG in addition to amplitude reduction. In cases of severe ischemia, the EEG becomes isoelectric. There are some limitations to use of EEG to monitor neurologic status during carotid surgery and these include that deeper structures are not able to be monitored, preexisting deficits are not accounted for or may result in lack of intraoperative EEG changes. EEG changes are also affected by temperature, blood pressure, CÓ tension and anesthetic depth.
A 5 kg 3-month-old full term boy presents for right inguinal hernia repair. A caudal block is performed with 1 ml/kg 0.25% bupivacaine during sevoflurane anesthesia via an endotracheal tube. The infant's vital signs prior to injection reveal a HR of 133 bpm, SBP 83 mmHg, upright T-waves in lead II. Which of the following is the MOST appropriate test dose of epinephrine? A-1 mcg B-2.5 mcg C-10 mcg D-25 mcg
B-2.5 mcg The dose of epinephrine required to identify intravascular injection for pediatric regional anesthesia during inhaled anesthesia is 0.5 mcg/kg up to a max of 15 mcg. Sethna described HR and BP changes with intravenous injections of 0.5 and 0.75 mcg/kg of epinephrine in infants greater than 3 mo. 0.5 mcg/kg was almost identical to 0.75 mcg/kg regarding heart response. SBP was more consistently elevated in patients receiving 0.75 mcg/kg of epinephrine.
Which of the following is the current recommendation by the American Society of Anesthesiologists (ASA) for the minimum fasting period before surgery for breast milk? A-2 hours B-4 hours C-6 hours D-8 hours E-Overnight
B-4 hours Present guidelines are 4 hours for breast milk. Other guidelines include: Clear liquids - 2 hours, Infant formula - 6 hours, Nonhuman milk - 6 hours, Light meal - 6 hour
Which of the following is the current recommendation by the American Society of Anesthesiologists (ASA) for the minimum fasting period before surgery for breast milk? A-2 hours B-4 hours C-6 hours D-8 hours E-Overnight
B-4 hours Present guidelines are 4 hours for breast milk. Other guidelines include: Clear liquids - 2 hours, Infant formula - 6 hours, Nonhuman milk - 6 hours, Light meal - 6 hours
Average blood loss during a vaginal delivery is: A-100 - 200 ml B-400 - 500 ml C-700 - 800 ml D-1000 - 1500 ml
B-400 - 500 ml At term, blood volume has increased by 1000 - 1500 ml in most women allowing them to easily tolerate the blood loss associated with delivery. Average blood loss during vaginal delivery is 400 - 500 ml, compared with 800 - 1000 ml for cesarean section.
Average blood loss during a vaginal delivery is: A-100 - 200 ml B-400 - 500 ml C-700 - 800 ml D-1000 - 1500 ml
B-400 - 500 ml At term, blood volume has increased by 1000 - 1500 ml in most women allowing them to easily tolerate the blood loss associated with delivery. Average blood loss during vaginal delivery is 400 - 500 ml, compared with 800 - 1000 ml for cesarean section.
The maximum recommended occupational whole-body exposure to radiation is: A-1 rem/year B-5 rem/year C-10 rem/year D-20 rem/year
B-5 rem/year The intraoperative use of imaging equipment exposes anesthesia providers to ionizing radiation. The maximum recommended whole-body exposure to radiation is 5 rem/year.
During emergent transtracheal jet ventilation using a 14 gauge catheter, generation of sufficient gas flow requires a driving pressure of: A- 20 cmH2O B-50 cmH2O C- 25 psi D-50 psi
B-50 psi After proper location of the catheter is confirmed by aspiration air, jet ventilation may be achieved with intermittent pulses of oxygen at 50 psi.
A 12-year-old girl presents for a posterior spine fusion. Except for idiopathic scoliosis, she is healthy and weighs 50 kg. Which of the following is the MOST appropriate dose of methadone? A-4 mg B-8 mg C-12 mg D-16 mg
B-8 mg Typical pediatric dosing of methadone includes a bolus of 0.1-0.2 mg/kg followed by 0.05 mg/kg every 6-8 hours.
A 9-month-old infant presents to the OR for a right inguinal hernia repair. The newborn screening was positive for beta-thalassemia major. Which of the following MOST accurately defines this condition? A-Absence of one of the beta-globin proteins B-Absence of both of the beta-globin protein C-Absence of one of the alpha-globin proteins D-Absence of both of the alpha-globin proteins
B-Absence of both of the beta-globin protein Normal hemoglobin has two alpha and two beta globin protein chains. A deficiency or absence of the alpha chain results in Alpha-thalassemia and a deficiency or absence of one or more of the beta chains results in Beta-thalassemia. The beta chain requires a gene from each parent to produce the correct quality and quantity of beta globin. If the gene from one parent is missing or incomplete, the child will develop Beta-thalassemia minor. If the gene from both parents is missing, the child will develop Beta-thalassemia major or Cooley's anemia.
A 55-year-old previously healthy woman presents with trigeminal neuralgia. Which of the following agents is the MOST appropriate first-line pharmacologic treatment? A-Amitriptyline B-Carbamazepine C-Oxycodone D-Phenytoin
B-Carbamazepine Trigeminal neuralgia is characterized by intense, stabbing pain in the distribution of the trigeminal nerve. The symptoms are usually unilateral. The patient may experience exacerbations with more frequent attacks, followed by remissions with fewer and less frequent attacks. Carbamazepine is the first line treatment for trigeminal neuralgia.
Which of the following would be LEAST likely to decrease mixed venous oxygen saturation (SVO2)? A-Anemia B-Cyanide poisoning C-Hypoxemia D-Shivering
B-Cyanide poisoning Cyanide poisoning results in the cell's inability to utilize oxygen for ATP production, thus the body's oxygen consumption (VO2) is low. SVO2 is inversely related to VO2, thus SVO2 would be expected to be high in cyanide poisoning. Shivering would result in the opposite -- an increase in VO2 and therefore a decrease in SVO2. Anemia and hypoxemia both result in a lower SVO2.
A 75-year-old man has had an infrarenal open abdominal aortic aneurysm repair under general anesthesia. His baseline preoperative creatinine, prior to surgery, was 1.1 mg/dL. On postoperative day 2, his creatinine increases to 2.0 mg/dL with a concomitant reduction in urine output. Which of the following physiologic changes is MOST associated with a reduction in renal function after aortic aneurysm surgery? A-Increase in renal cortical blood flow B-Decrease in renal cortical blood flow C-Decrease in renal vascular resistance D-Increase in glomerular filtration rate
B-Decrease in renal cortical blood flow The effects of the aortic cross-clamp on the kidneys are mediated by both the renin-angiotensin-aldosterone system as well as the sympathetic nervous system. There is an increase in renal vascular resistance, decrease in renal cortical blood flow and decrease in glomerular filtration rate. An infrarenal cross clamp can decrease renal blood flow by 40% whereas a thoracic level aortic clamp decreases renal blood flow by as much as 80-90%. These changes persist for a long period of time after the cross clamp is removed. In addition, the decrease in renal blood flow is not necessarily associated with decreased cardiac output or decreased mean arterial blood pressure (although those changes would certainly not improve renal function or prevent the decrement).
An 80-year-old man undergoes an abdominal aortic aneurysm repair with an oximetric pulmonary artery catheter. The mixed venous oxygen saturation (SvÓ) increases from 70 to 80% after the aortic cross-clamp is placed. Which of the following MOST likely accounts for the increase in mixed venous oxygen saturation? A-Decreased carbon dioxide production B-Decreased oxygen consumption C-Increased afterload D-Increased preload
B-Decreased oxygen consumption During the time period of the aortic crossclamp, there is increased mixed venous oxygen saturation as there is a reduction in total body oxygen consumption and decreased total body oxygen extraction. Other factors that impact mixed venous oxygen saturation include arterial oxygen saturation, hemoglobin concentration and cardiac output. During aortic cross-clamping these variables may also change, but they likely would be responsible for decreasing the mixed venous oxygen saturation (in the case of arterial desaturation, bleeding, decreased cardiac output).
An otherwise healthy 25-year-old G1P0 is taken emergently to the OR for cesarean delivery. She receives a bolus of 30 mL of 2-chloroprocaine through an existing epidural catheter. Which of the following is MOST correct regarding the use of 3% 2-chloroprocaine? A-Its rapid onset is a result of its high pKa. B-Efficacy of epidurally administered opioids may be decreased. C-It is rapidly metabolized by the liver and kidneys. D-Fetal acidosis leads to high levels in fetal circulation.
B-Efficacy of epidurally administered opioids may be decreased. 2-Chloroprocaine is considered a safe and favorable choice for emergent/urgent dosing of an epidural for cesarean section. It is favorable because of its rapid onset, which is independent of its pKa (based on pKa alone, one would expect a very slow onset). The rapid onset is thought to be due to the high concentrations that are used. It is safe because it is metabolized by plasma cholinesterases (it is an ester local anesthetic), so intravascular injection is clinically inconsequential. A down side of its use is its relatively short duration; repeat boluses must be given about every 30 minutes to maintain surgical anesthesia. The use of 2-chloroprocaine is associated with a decreased efficacy of subsequent epidural opioids, rather than increased efficacy.
A patient with diabetic ketoacidosis is scheduled for an emergent laparotomy. Which of the following best explains the decrease in serum potassium concentration that occurs in this patient following administration of insulin? A-Dilutional hypokalemia follows free water retention from decreased osmotic diuresis B-Extracellular potassium is actively transported with glucose into cells C-Insulin enhances renal excretion of potassium D-Intracellular potassium is exchanged for extracellular glucose
B-Extracellular potassium is actively transported with glucose into cells
In acute hemorrhage and resuscitation, which of the following coagulation factors is MOST likely to reach a critically low level first? A-Factor VIII B-Fibrinogen C-Platelets D-Thrombin (Factor IIa)
B-Fibrinogen Fibrinogen will reach a critical level (i.e., below 100 mg/dL) after loss of about 1.5 blood volumes. Other coagulation factors typically reach critical levels after about 2 to 2.5 blood volumes.
A patient with severe mitral stenosis presents for mitral valve replacement. Which of the following statements is LEAST correct regarding the management of this patient? A-Hemodynamic goals include increasing preload, decreasing heart rate, and maintaining SVR. B-Following PA catheter placement, one would expect to see giant V waves on pulmonary capillary wedge tracing C-During TEE examination, one would expect a mean pressure gradient >10 mm Hg calculated across the stenotic mitral valve. D-Pulmonary capillary wedge pressure reflects left atrial pressure but not LV filling pressures.
B-Following PA catheter placement, one would expect to see giant V waves on pulmonary capillary wedge tracing. Mitral stenosis produces large A-waves on the pulmonary capillary wedge pressure tracing while mitral regurgitation produces giant V waves. All of the other statements above are true regarding the management of a patient with severe mitral stenosis.
Which of the following describes the MOST current management of cerebral perfusion pressure in patients with aneurysmal subarachnoid hemorrhage and cerebral vasospasm? A-HHH Therapy (Hypertensive, Hypervolemic, Hemodilutional) B-Hypertensive Euvolemia C-Hypotensive therapy to minimize cerebral edema D-Normotension with nicardipine infusion to dilate cerebral vessels.
B-Hypertensive Euvolemia HHH therapy has now become hypertensive therapy in the management of cerebral vasospasm. While we want to avoid hypovolemia, it is clear that hypervolemia carries significant morbidity, such as pulmonary complications. Blood pressure is titrated upward until neurologic symptoms subside. The exact blood pressure goal is subjective and tailored to the individual patient. Typical SBP values range from 160-200 mmHg.
Which of the following anomalies is MOST likely to be associated with congenital diaphragmatic hernia? A-Horseshoe kidney B-Hypoplastic left heart C-Radial limb anomalies D-Vertebral anomalies
B-Hypoplastic left heart A congenital diaphragmatic hernia (CDH) is an early developmental defect that results in the extrusion of intraabdominal organs (i.e. stomach, small intestines, kidney, liver) into the thoracic cavity. Significant cardiac disease is associated with at least 10% of of patients with CDH. Survival for patients with cardiac disease is significantly lower than for patients with normal cardiac anatomy. Patients with CDH and univentricular cardiac anatomy have a poor prognosis.
A 74-year-old man with chronic atrial fibrillation is brought to the emergency room four hours after the acute onset of left hemiparesis. A CT angiogram reveals a right middle cerebral artery (M1 segment) occlusion. He is unable to get IV t-PA within the required window and is brought to the neurointerventional suite for endovascular clot extraction. Which of the following complications is MOST associated with a general anesthetic technique for this procedure? A-Anesthetic neurotoxicity B-Hypotension/hypoperfusion C-Inability to examine the patient during the procedure D-Aspiration pneumonia and urosepsis
B-Hypotension/hypoperfusion The use of general anesthesia for acute stroke interventions is requested by many endovascular neurosurgeons, but recent retrospective data points to an association between the use of GA and worse outcome (Froehler, 2012). Prospective studies are needed. In the interim, it appears that hypotension in the setting of GA is the most likely culprit (Davis, 2012). Other possibilities include time delay in mobilizing anesthesia resources, and/or placing a patient on a critical care treatment pathway with associated morbidities (such as ongoing intubation, ventilator associated pneumonia, etc.).
An otherwise healthy 75-year-old man taking no medications undergoes an uneventful spinal anesthetic with lidocaine for an outpatient cystoscopy. The next day, the patient calls complaining of excruciating lower back pain that radiates down both legs. Which if the following is MOST appropriate action? A-Have the patient see his urologist for examination, as the pain is secondary to the lithotomy position. B-If no other symptoms are present, reassure the patient that this pain will improve in a few days C-Order a spine MRI D-Obtain an immediate neurological consultation.
B-If no other symptoms are present, reassure the patient that this pain will improve in a few days. These are common symptoms associated with TNS (transient neurologic symptoms) and are associated with lidocaine spinals, specifically in the lithotomy position. The symptoms usually improve with NSAIDs and resolve in a few days. An MRI would be the most useful test if you suspect a neuraxial hematoma. A neuraxial hematoma is extremely rare, especially in patients with no risk factors and those not receiving anticoagulants. Symptoms of a neuraxial hematoma are generally increased sensory/motor block and/or bowel and bladder dysfunction. Neuraxial hematomas do not typically present with severe radicular pain. The patient should be encouraged to call his urologist or anesthesiologist if the pain does not improve or worsens over the next day or two.
Which of the following physiologic changes that improve oxygen delivery to the fetus during normal pregnancy is LEAST likely? A-Increased cardiac output B-Increased hematocrit C-Increased PaO2 D-Maternal hyperventilation
B-Increased hematocrit Several physiologic alterations normally occur to create favorable conditions for oxygen delivery to the fetus. Minute ventilation and PaO2 increase via increased tidal volume and respiratory rate, to compensate for the increase in oxygen consumption and carbon dioxide production. Oxygenated hemoglobin is delivered swiftly in larger amounts as a result of increased cardiac output. Although the number of intravascular red cells is increased 30%, a concurrent 45% increase in blood volume at term results in relative hemodilution. Thus, although higher total amounts of red cells and hemoglobin are produced for oxygen delivery, there is actually a decreased hematocrit ("physiologic anemia of pregnancy").
Which of the following physiologic changes that improve oxygen delivery to the fetus during normal pregnancy is LEAST likely? A-Increased cardiac output B-Increased hematocrit C-Increased PaÓ D-Maternal hyperventilation
B-Increased hematocrit Several physiologic alterations normally occur to create favorable conditions for oxygen delivery to the fetus. Minute ventilation and PaÓ increase via increased tidal volume and respiratory rate, to compensate for the increase in oxygen consumption and carbon dioxide production. Oxygenated hemoglobin is delivered swiftly in larger amounts as a result of increased cardiac output. Although the number of intravascular red cells is increased 30%, a concurrent 45% increase in blood volume at term results in relative hemodilution. Thus, although higher total amounts of red cells and hemoglobin are produced for oxygen delivery, there is actually a decreased hematocrit ("physiologic anemia of pregnancy").
You are taking care of a 6-week-old infant with congenital lobar emphysema. He was born full term and was doing well at home until he developed respiratory distress. He is scheduled for a left upper lobe resection via a thoracotomy. He has been NPO for breast milk for 6 hours and he is now in the operating room. After the placement of standard ASA monitors, what is the MOST appropriate immediate anesthetic plan? A-Inhalation induction, controlled ventilation, double lung ventilation. B-Inhalation induction, spontaneous ventilation, single lung ventilation. C-Intravenous induction, controlled ventilation, single lung ventilation. D-Intravenous induction, spontaneous ventilation, double lung ventilation.
B-Inhalation induction, spontaneous ventilation, single lung ventilation. Congenital lobar emphysema is a developmental anomaly of the lung that is characterized by hyperinflation of one or more of the pulmonary lobes. In patients with congenital lobar emphysema, an inhalation induction that maintains spontaneous ventilation is preferred. Positive pressure ventilation may cause respiratory compromise or pneumothorax. After the induction of anesthesia the airway is secured with an endotracheal tube. Lung isolation is recommended to minimize inflation of the emphysematous lung. This can be achieved with an endobronchial intubation, bronchial blocker or a Fogarty catheter.
Which of the following drugs is included in Step 1 in the World Health Organization (WHO) analgesic ladder? A-Codeine B-Ketoprofen C-Propoxyphene D-Tramadol
B-Ketoprofen The World Health Organization (WHO) analgesic ladder was established in 1986 to guide physicians developing treatment plans for cancer pain. In general terms, Step 1 includes Non-opioid analgesics, with or without adjuvants. Step 2 includes "weak" opioids (such as codeine, propoxyphene, and tramadol), with or without adjuvants. Step 3 includes "strong" opioids (such as morphine, fentanyl, and methadone) and non-opioids, without or without adjuvants. Ketoprofen is the only non-opioid listed.
Which of the following ligaments is traversed when using a paramedian approach to the neuraxis? A-Interspinous ligament B-Ligamentum flavum C-Posterior longitudinal ligament D-Supraspinous ligament
B-Ligamentum flavum The supraspinous and interspinous ligaments are both midline structures and are not traversed in a paramedian approach. The only structure traversed in both midline and paramedian approaches is the ligamentum flavum. The posterior longitudinal ligament is anterior to the spinal cord and not traversed in either the paramedic or midline approaches.
A 28-year-old woman with a grossly infected ingrown toe nail presents for debridement of the affected area. The great toe is swollen, with red streaks radiating up the foot. The orthopedic surgeon plans to inject local anesthetic directly into the infected area prior to debriding the toe. Which of the following BEST explains why the injection of local anesthetics into an abscess is LESS effective than an ankle block? A-More highly protein bound in acidotic tissue B-More highly ionized in acidotic tissue C-More highly lipid soluble in acidotic tissue D-More rapidly metabolized in acidotic tissue
B-More highly ionized in acidotic tissue Onset of action is largely dependent on the Pka of the local anesthetic and the total dose administered. Nonionized forms of local anesthetics pass more easily through lipid bilayer; therefore, in an acidic environment there will be more local anesthetic in the ionized form and the onset will be slower and patchy.
Small amounts of opioids are often used to supplement the analgesic and anesthetic effects of local anesthetics administered in the epidural space. In the obstetric patient, which of the following is the MOST common side effect of 100 mcg of epidural fentanyl? A-Difficulty "pushing" if administered too close to delivery B-Pruritus C-Respiratory depression D-Uterine atony
B-Pruritus Intrathecal fentanyl results in profound visceral pain relief. As fentanyl is highly lipophilic, it rapidly leaves cerebrospinal fluid and penetrates the spinal cord as well as the systemic circulation. In contrast to local anesthetics, fentanyl does not contribute to motor block or difficulty pushing. Unlike the more hydrophilic morphine, fentanyl does not have significant rostral spread within the intrathecal space and is therefore not thought to contribute to maternal respiratory depression. Common side effects of intrathecal fentanyl include pruritus (especially of the nose and trunk) and nausea, although pruritus is the most common. Epidural administration of fentanyl also results in significant systemic absorption. It can cross the placenta and result in a transient decrease in fetal heart rate variability, which can make interpretation of fetal heart rate patterns challenging. It is not thought to contribute to newborn respiratory depression under normal circumstances. Santos AC, Bucklin BA. Local Anesthetics and Opioids. In: Chestnut DH, ed. Obstetric Anesthesia. 4th ed. Philadelphia: Mosby Elsevier, 2009:247-282.
The arteria radicularis magna, or artery of Adamkiewicz, most commonly arises from: A-T4 - T8 B-T8 - L2 C-L2 - L4 D-L4 - S1
B-T8 - L2 A major complication of thoracic aortic surgery is paraplegia, occurring in up to 20% of elective cases, and is secondary to spinal cord ischemia. The arteria radicularis magna supplies blood to the anterior spinal artery. The arteria radicularis magna has a variable origin from aorta, arising between T5 - T8 in 15%, between T9 - T12 in 60% and between L1 - L2 in 25% of individuals.
Which of the following pacemaker modes would be MOST appropriate in the PACU for a bradycardic patient with chronic atrial fibrillation? A-AVI B-VVI C-DDI D-VAT
B-VVI A fibrillating atrium cannot be paced, therefore pacemaker codes with the 1st letter (chamber paced) of 'A' or 'D' would not be appropriate. Additionally, it would not be desirable to transmit the atrial signal to the ventricle, so codes with the 2nd letter (chamber sensed) of 'A' or 'D' are not the best answer. Sensing the ventricle and inhibiting the pacemaker when a signal is present to avoid the 'R on T' phenomenon would be most appropriate.
Renal blood flow: (Select 2) A-is largely determined by renal oxygen consumption. B-accounts for 20 - 25% of the cardiac output C-is distributed mostly to juxtamedullary nephrons D-can be directed away from cortical nephrons by sympathetic stimulation. E-is not autoregulated
B-accounts for 20 - 25% of the cardiac output, D-can be directed away from cortical nephrons by sympathetic stimulation. The kidneys are the only organ for which oxygen consumption is determined by blood flow; the reverse is true in other organs. The kidneys receive 20 - 25% of the cardiac output with only 10 - 15% going to the juxtamedullary nephrons and 80% going to cortical nephrons. However, blood flow can be redirected to juxtamedullary nephrons by increased levels of catecholamines and angiotensin II. Autoregulation of RBF occurs between mean arterial pressures of 80 - 180 mm Hg.
Safety features that prevent filling of the vaporizer with an incorrect agent include: A-the pin index safety system B-agent-specific keyed filling ports C-the diameter index safety system D-counter-threading of the bottle attachment
B-agent-specific keyed filling ports Modern vaporizers offer agent-specific keyed filling ports to prevent filling with an incorrect agent. The pin-index safety system is found on e-cylinders to prevent incorrect tank placement.
Correct statements concerning the use of antidepressants in pain management include: A-analgesic effects require a higher dose than that needed for antidepression. B-analgesic effects appear to be secondary to the blockade of serotonin and norepinephrine reuptake. C-antidepressants are not effective in neuropathic pain. D-newer SSRIs are more effective analgesics than the older tricyclic antidepressants.
B-analgesic effects appear to be secondary to the blockade of serotonin and norepinephrine reuptake Antidepressants demonstrate an analgesic effect at doses lower that those needed for antidepressant effect. Both actions appear secondary to the block of the reuptake of serotonin and norepinephrine. Older tricyclic antidepressants seem more effective analgesics than the newer SSRIs. Antidepressants are most useful in patients with neuropathic pain.
Release of aldosterone by the adrenal cortex is stimulated by: (select 3) A-angiotensin I B-angiotensin II C-hypokalemia D-pituitary ACTH E-congestive heart failure F-hypervolemia
B-angiotensin II, D-pituitary ACTH, E-congestive heart failure Aldosterone release is stimulated by the renin-angiotensin system, but specifically by angiotensin II. Other causes of aldosterone release include hyperkalemia, ACTH release, hypovolemia, hypotension, CHF and the stress response.
The most consistent clinical manifestation of aspiration pneumonitis is: A-bronchospasm B-arterial hypoxemia C-pulmonary vasoconstriction D-tachypnea
B-arterial hypoxemia Inhaled gastric fluid is rapidly distributed throughout the lungs, leading to destruction of surfactant-producing cells, damage to the pulmonary capillary endothelium and resultant atelectasis and pulmonary edema. Arterial hypoxemia is the most consistent clinical finding associated with aspiration pneumonitis. Tachypnea, bronchospasm and pulmonary vasoconstriction with secondary pulmonary hypertension may also be present.
Local anesthetic solutions that are isobaric with the cerebrospinal fluid include: (Select 2) A-tetracaine 0.5% in 5% dextrose B-bupivacaine 0.75% in normal saline C-procaine 10% in sterile water D-lidocaine 2% in normal saline E-bupivacaine 0.3% in sterile water F-lidocaine 5% in 7.5% dextrose
B-bupivacaine 0.75% in normal saline, D-lidocaine 2% in saline
Sinus arrhythmia: A- is mediated through sympathetic innervation of the AV node B- causes an increase in heart rate with inspiration C- is indicative of SA node ischemia D- is the primary cause of premature atrial contractions
B-causes an increase in heart rate with inspiration Sinus arrhythmia is a cyclic variation in heart rate that corresponds to ventilation, increasing with inspiration and decreasing with expiration. Sinus arrhythmia is a normal cardiac rhythm and is due to cyclic changes in vagal tone.
Concerning preoperative informed consent: A-it should disclose only life-threatening complications B-charges of assault and battery are possible if it is not obtained C-oral consent is insufficient D-it is not necessary if the procedure is done in an office setting
B-charges of assault and battery are possible if it is not obtained Any procedure performed without the patient's consent can constitute assault and battery. Oral consent may be sufficient, but written consent is advisable for medicolegal purposes. It is generally accepted that not all risks need to be detailed, but risks that are realistic and have resulted in complications in similar patients should be disclosed.
Concerning preoperative informed consent: A-it should disclose only life-threatening complications. B-charges of assault and battery are possible if it is not obtained. C-oral consent is insufficient. D-it is not necessary if the procedure is done in an office setting.
B-charges of assault and battery are possible if it is not obtained. Any procedure performed without the patient's consent can constitute assault and battery. Oral consent may be sufficient, but written consent is advisable for medicolegal purposes. It is generally accepted that not all risks need to be detailed, but risks that are realistic and have resulted in complications in similar patients should be disclosed.
The synthesis of acetylcholine from acetylcoenzyme A and choline is catalyzed by: A-free acetate anion B-choline acetyltransferase C-acetyl cholinesterase D-pseudocholinesterase
B-choline acetyltransferase The synthesis of acetylcholine occurs in the cholinergic nerve terminal. Acetyl Co-A and choline combine to form acetylcholine. This reaction is catalyzed by the enzyme choline acetyltransferase.
Parasympathetic preganglionic fibers are found in: (Select 3) A-cranial nerve IV B-cranial nerve VII C-cranial nerve IX D-cranial nerve XI E-thoracic nerve 9 F-thoracic nerve 11 G-sacral nerve 1 H-sacral nerve 2
B-cranial nerve VII, C-cranial nerve IX, H-sacral nerve 2 Parasympathetic preganglionic fibers are found in cranial nerves III, VII, IX and X as well as sacral nerves 2, 3 and 4.
Renal effects of nitrous oxide include: A-decreased renal blood flow secondary to decreased cardiac output. B-decreased renal blood flow secondary to increased renal vascular resistance. C-increased renal blood flow secondary to sympathetic stimulation D-increased glomerular filtration with increased reabsorption
B-decreased renal blood flow secondary to increased renal vascular resistance Nitrous oxide appears to decrease renal blood flow by increasing renal vascular resistance. This results in decreased glomerular filtration and decreased urine output.
Termination of the effects of succinylcholine at the neuromuscular junction occurs as a result of: A-succinylcholine hydrolysis by acetylcholinesterase. B-diffusion of succinylcholine away from the receptors C-succinylchoine hydrolysis by hepatic esterases D-the competition of succinylcholine with acetylcholine
B-diffusion of succinylcholine away from the receptors. Because depolarizing muscle relaxants are not metabolized by acetylcholinesterase, they diffuse away from the neuromuscular junction and are hydrolyzed in the plasma by pseudocholinesterase.
During mediastinoscopy the risk of air embolization is greatest: A-when the patient is supine B-during spontaneous ventilation C-immediately after closure of the incision D-in the postoperative period
B-during spontaneous ventilation Air embolization is seen with mediastinoscopy as a result of the 30o elevation of the head. This risk is increased if the patient is spontaneously ventilating, secondary to the negative intrathoracic pressures generated during inhalation.
Nerves blocked with a fascia iliaca block include the: A-sciatic nerve B-femoral nerve C-pudendal nerves D-anterior tibial nerve
B-femoral nerve The fascia iliaca block utilizes a deposition of local anesthetic in the fascia iliaca compartment to block the femoral, lateral femoral cutaneous, obturator and genitofemoral nerves.
Nerves blocked with a fascia iliaca block include the: A-sciatic nerve B-femoral nerve C-pudendal nerves D-anterior tibial nerve
B-femoral nerve The fascia iliaca block utilizes a deposition of local anesthetic in the fascia iliaca compartment to block the femoral, lateral femoral cutaneous, obturator and genitofemoral nerves.
Nerves blocked with a fascia iliaca block include the : A-sciatic nerve B-femoral nerve C-pudendal nerves D-anterior tibial nerve
B-femoral nerve The fascia iliaca block utilizes a deposition of local anesthetic in the fascia iliaca compartment to block the femoral, lateral femoral cutaneous, obturator and genitofemoral nerves.
Selective adrenergic stimulation of the β2-receptor results in: A-increased heart rate B-increased insulin secretion C-detrusor muscle contraction D-pupillary constriction
B-increased insulin secretion β2-receptor stimulation results in: increased insulin secretion, bronchodilation, increased salivary gland secretion, decreased upper GI motility, gluconeogenesis, pupillary dilation and detrusor muscle relaxation. Increased heart rate is a result of β1-receptor stimulation. Pupillary constriction (miosis) is the result of parasympathetic stimulation.
The addition of bicarbonate to a local anesthetic solution: A- delays the onset of blockade B- increases the concentration of the nonionic form of the local anesthetic. C-causes a fall in the pH of the solution D- should only be done when using bupivacaine
B-increases the concentration of the nonionic form of the local anesthetic The onset of neural blockade depends on the penetration of the nerve cell membrane by the nonionic form of the anesthetic. Increasing the pH of the anesthetic solution increases the concentration of the nonionic form and thereby hastens the onset of the block. Bicarbonate is usually not added to bupivacaine, since it can cause precipitation if the pH is raised above 6.8
The addition of bicarbonate to a local anesthetic solution: A-delays the onset of blockade B-increases the concentration of the nonionic form of the local anesthetic C-causes a fall in the pH of the solution D-should only be done when using bupivacaine
B-increases the concentration of the nonionic form of the local anesthetic The onset of neural blockade depends on the penetration of the nerve cell membrane by the nonionic form of the anesthetic. Increasing the pH of the anesthetic solution increases the concentration of the nonionic form and thereby hastens the onset of the block. Bicarbonate is usually not added to bupivacaine, since it can cause precipitation if the pH is raised above 6.8.
Dantrolene: (Select 2) A-depends on an extracellular mechanism to achieve muscle relaxation. B-inhibits calcium ion release from the sarcoplasmic reticulum. C-can also be used in the treatment of thyroid storm. D-therapy should not be repeated after an MH episode has terminated. E-has a half-life of approximately 12 hours
B-inhibits calcium ion release from the sarcoplasmic reticulum. C-can also be used in the treatment of thyroid storm. Dantrolene binds with the Ryr1 receptor and inhibits calcium ion release from the sarcoplasmic reticulum. Dantrolene's effects are intracellular and may result in muscle weakness and ventilatory insufficiency. The half-life of dantrolene is approximately 6 hours. Dantrolene has also been used to treat neuroleptic malignant syndrome and thyroid storm.
Physiologic effects of electroconvulsive therapy (ECT) include an: A-initial sympathetic response with sustained tachycardia. B-initial sympathetic discharge followed by a sustained parasympathetic response. C-initial parasympathetic discharge followed by a sustained sympathetic response. D-initial parasympathetic response with sustained bradycardia.
B-initial parasympathetic discharge followed by a sustained sympathetic response. An initial parasympathetic discharge followed by a sustained sympathetic response is immediately seen after the induction of a seizure. Marked bradycardia with increased secretions can occur, which is then followed by hypertension and tachycardia. Patients scheduled for ECT are routinely given anticholinergic medication preoperatively.
Highly specific preoperative screening tests have a: A-low incidence of false-positives results B-low incidence of false-negative results C-result that is specific for one pathologic process D- low sensitivity
B-low incidence of false-positives results The usefulness of a screening test depends on its sensitivity and specificity. Sensitive tests have a low rate of false-negative results, whereas specific tests have a low rate of false-positive results.
Ulnar nerve injury: A-results in wrist drop and loss of sensation in the web space between the thumb and index finger B-occurs more frequently in males C-manifests itself in the immediate postoperative period D- is most commonly seen in the patient with a BMI of less than 18
B-occurs more frequently in males Three attributes which are highly associated with development of postoperative ulnar nerve injury are: 1) male sex - various reports suggest that 70 - 90% of patients with postoperative ulnar neuropathy are men 2) high body mass index - BMI > or = 38 3) prolonged postoperative bed rest. Many patients with postoperative ulnar neuropathy have a high frequency of contralateral ulnar nerve dysfunction, suggestive of a pre-existing abnormality. Patients may not develop symptoms of ulnar neuropathy until more than 48 hours postoperatively. Wrist drop and loss of sensation of the web space between the thumb and index finger are associated with radial nerve injury.
Ulnar nerve injury: A-results in wrist drop and loss of sensation in the web space between the thumb and index finger. B-occurs more frequently in males. C-manifests itself in the immediate postoperative period. D-is most commonly seen in the patient with a BMI of less than 18.
B-occurs more frequently in males. Three attributes which are highly associated with development of postoperative ulnar nerve injury are: 1) male sex - various reports suggest that 70 - 90% of patients with postoperative ulnar neuropathy are men 2) high body mass index - BMI > or = 38 3) prolonged postoperative bed rest. Many patients with postoperative ulnar neuropathy have a high frequency of contralateral ulnar nerve dysfunction, suggestive of a pre-existing abnormality. Patients may not develop symptoms of ulnar neuropathy until more than 48 hours postoperatively. Wrist drop and loss of sensation of the web space between the thumb and index finger are associated with radial nerve injury.
An occurrence malpractice insurance policy: A-offers coverage if the policy was in place at the time of the incident, regardless of when the claim is filed. B-offers coverage if the policy is in place at the time the claim is filed. C-is activated at the time of the need to pay a claim that exceeds the limits of coverage on the standard malpractice policy. D-is the most common form of malpractice insurance in place today.
B-offers coverage if the policy was in place at the time of the incident, regardless of when the claim is filed. An occurrence policy offers coverage of an incident resulting in a claim, whenever that claim might be filed. The much more common claims-made policy covers claims that are filed only while the insurance is in force. Umbrella coverage is activated at the time of the need to pay a claim that exceeds the limits of coverage on the standard malpractice policy.
A decrease in cerebral blood flow is seen after the administration of: A-isoflurane B-propofol C-desflurane D-ketamine
B-propofol The inhaled anesthetic agents and ketamine all increase cerebral blood flow (CBF). Benzodiazepines, etomidate, propofol and barbiturates all decrease CBF.
A decrease in cerebral blood flow is seen after the administration of: A isoflurane B- propofol C- desflurane D- ketamine
B-propofol The inhaled anesthetic agents and ketamine all increase cerebral blood flow (CBF). Benzodiazepines, etomidate, propofol and barbiturates all decrease CBF.
The formation of active metabolites has NOT been associated with the use of: A-vecuronium B-rocuronium C-pancuronium D-succinylcholine
B-rocuronium The 3-OH metabolites of both vecuronium and pancuronium possess about 50% of the neuromuscular blocking activity of parent compound. Succinylcholine is metabolized to choline, succinic acid and succinylmonocholine. Succinylmonocholine also has some neuromuscular blocking activity. A small amount of rocuronium is metabolized to the 17-OH compound, which lacks activity. Most rocuronium is excreted by the kidneys and liver as intact drug.
The rhythm strip below is indicative of: A-first degree block B-second degree block, type I C-second degree block, type II D-bifascicular block
B-second degree block, type I Second degree block, type I, shows a progressive lengthening of the PR interval with each cycle until a QRS complex is dropped. This type of block indicates AV nodal disease and associated bradycardia usually responds to the administration of atropine.
Reactants that are regenerated during the absorption of carbon dioxide by soda lime include: A-carbonic acid B-sodium hydroxide C-calcium hydroxide D-calcium carbonate
B-sodium hydroxide Both water and sodium hydroxide are initially required during the absorption of carbon dioxide by soda lime, but then are regenerated.
Reactants that are regenerated during the absorption of carbon dioxide by soda lime include: A-carbonic acid B-sodium hydroxide C-calcium hydroxide D-calcium carbonate
B-sodium hydroxide Both water and sodium hydroxide are initially required during the absorption of carbon dioxide by soda lime, but then are regenerated.
A 5-day-old male is scheduled for a pyloromyotomy. The patient has experienced two episodes of apnea since birth. Anesthetic management shown to reduce the incidence of postoperative apnea includes: A-the use of ketamine as the sole anesthetic agent B-the intravenous administration of caffeine C-use of desflurane as the sole anesthetic agent D-the avoidance of nitrous oxide
B-the intravenous administration of caffeine. Both caffeine and theophylline have been shown to reduce the incidence of postoperatitive apnea in infants at increased risk. Caffeine is favored because of its wider therapeutic margin. The recommended loading dose is 10 mg/kg caffeine base.
Venous irritation associated with the injection of diazepam and lorazepam is secondary to: A-the high degree of water solubility of these agents B-the presence of propylene glycol as a solvent C-the presence of metabisulfite as a preservative D-the low pH of these agents
B-the presence of propylene glycol as a solvent The insolubility of diazepam and lorazepam in water requires that parenteral preparations contain propylene glycol, which has been associated with venous irritation.
During fetal monitoring, Type III decelerations are thought to be related to: A-head compression B-umbilical cord compression C-uteroplacental insufficiency D-placental abruption
B-umbilical cord compression Type III, or variable, decelerations are the most common type of decelerations. They are thought to be related to umbilical cord compression and intermittent decreases in umbilical blood flow.
An anxiolytic herbal medication associated with a decrease in the requirement of inhaled anesthetic agent (MAC) is: A-echinacea B-valerian C-ginkgo D-ephedra
B-valerian Both valerian and kava have been shown to have a GABA-mediated hypnotic effect and by this mechanism decrease MAC. Acute withdrawal after chronic use may result in an increase in MAC.
You are taking over a case from another anesthesia provider with a patient in the beach chair position and a history of moderate carotid artery disease. You are told during pass-off that the patient's blood pressures have consistently been 90/50 mm Hg. You notice the blood pressure cuff on the left arm is one or two sizes small and barely stays on the patient. A blood pressure cuff that is too small will A. Incorrectly underestimate the true blood pressure B. Incorrectly overestimate the true blood pressure C. Randomly both over- and underestimate the true blood pressure D. Not give an incorrect blood pressure, but will be uncomfortable in an awake patient
B. A properly-sized noninvasive blood pressure cuff should encompass 40% of the circumference of the arm. A cuff that is too small will result in a reading that is incorrectly high, whereas a cuff that is too large will result in a lower-than-accurate pressure. This is particularly worrisome in this patient when considering her cerebral perfusion pressure, since she already has a history of carotid artery disease and is in the beach chair position.
If you notice that the CÓ absorbent is exhausted during the surgical procedure, which of the following minimal fresh gas flows (L/min) will make the CÓ absorbent unnecessary? A. 3 B. 5 C. 7 D. 10
B. Advantages of a circle system include the use of low fresh gas flow rates because of the presence of a CÓ-absorbent canister. However, if the CÓ absorbent is exhausted during a surgical procedure, the fresh gas flow rate has to be increased. A minimum fresh gas flow rate of 5 L/min will make the use of the absorbent unnecessary. Newer anesthesia machines allow changing the CÓ-absorbent canister during the surgical procedure, if necessary.
Insertion of a pulmonary artery catheter can be beneficial in the management of all of the following cases, except A. Helping to determine cardiogenic versus: noncardiogenic pulmonary edema B. Following cardiac output in an unstable patient with acute-onset tricuspid regurgitation C. Following the response to therapy in a patient with severe pulmonary hypertension D. Following response to therapy in an unstable septic patient using mixed venous oxygen tension
B. As well as knowing some valuable indications, it is important to know some of the limitations of a pulmonary artery catheter before subjecting a patient to risks. For example, the measurement of cardiac output in patients with tricuspid regurgitation or ventricular septal defects is inaccurate due to dilution of the injectate. Pulmonary artery occlusion pressure can also inaccurately represent left ventricular end diastolic pressure in patients with mitral stenosis, left atrial myxomas, pulmonary venous obstruction, elevated alveolar pressures, and decreased left ventricular compliance. Other common errors in measurement that are not patient dependent can include an inaccurate volume or temperature of the injectate solution
Cerebral perfusion pressure (CPP) (mm Hg) in a patient with intracranial pressure (ICP) of 12 mm Hg, central venous pressure (CVP) of 15 mm Hg, and mean arterial pressure (MAP) of 70 mm Hg will be A. 58 B. 55 C. 52 D. 48
B. CPP = MAP − ICP or CVP, whichever is higher. Thus, CPP = 70 − 15 = 55 mm Hg
An initial bolus of pancuronium was administered to a patient with end-stage liver disease with associated ascites for general anesthesia. Appropriate anesthetic considerations include all of the following, except A. Increased sympathomimetic activity due to vagolysis B. Intense histamine release immediately after administration C. Larger volume of distribution requiring initial larger doses D. Longer duration of action requiring smaller maintenance doses
B. Chronic liver disease may interfere with the metabolism of drugs due to decreased number of functional hepatocytes or decreased hepatic blood flow that typically accompanies cirrhosis of the liver. Prolonged elimination half-life times for morphine, diazepam, lidocaine, pancuronium, and, to a lesser degree, vecuronium have been demonstrated in this population. Cirrhotic patients will require a larger initial dose of pancuronium due to increased volume of distribution for this hydrophilic agent with smaller maintenance doses for prolonged duration of action. Pancuronium has slight vagolytic activity resulting in increased heart rate and cardiac output. Mivacurium and atracurium are associated with histamine release.
Current ASA standards require that during anesthesia, systemic blood pressure and heart rate be evaluated at least every: A. 3 minutes B. 5 minutes C. 7 minutes D. 10 minutes
B. During the delivery of anesthesia, the current standard of care is to measure systemic blood pressure and heart rate every 5 minutes at a minimum. The clinical scenario and phase of the operation may mandate more frequent monitoring, which is up to the judgment of the anesthesia provider.
Consider that the patient opens his eyes and is extubated in the operating room. However, 15 minutes after arriving to the recovery room (PACU) he is unable to maintain adequate ventilation and oxygenation. Physical exam reveals profound global weakness with absent reflexes. The specific electrolyte abnormality that should be evaluated considering his TPN requirement is A. Potassium B. Phosphate C. Sodium D. Glucose
B. Ensuring the presence of normal serum phosphate levels in the patient receiving TPN is essential, as hypophosphatemia has been associated with acute respiratory failure due to profound areflexic muscle weakness.
Each of the following is hemodynamic change associated with hypercarbia, except A. Arrhythmias B. Bradycardia C. High cardiac output D. Low systemic vascular resistance (SVR)
B. Hypercarbia causes hemodynamic changes by its direct action on the cardiovascular system and indirect actions through the sympathetic nervous system. Manifestations while under general anesthesia include tachycardia, arrhythmias, high cardiac output, increased arterial blood pressure, and low SVR with flushed skin
Lead II of an ECG is represented by placing the: A. Positive electrode on the right arm and the negative electrode on the left leg B. Negative electrode on the right arm and the positive electrode on the left leg C. Positive electrode on the right arm and the negative electrode on the left arm D. Negative electrode on the right arm and the positive electrode on the left arm
B. Lead I correlates with the placement of the negative electrode on the right arm and the positive electrode on the left arm. Lead II correlates with the placement of the negative electrode on the right arm and the positive electrode on the left leg. Lead III correlates with the placement of the negative electrode on the left arm and the positive electrode on the left leg
The National Institute for Occupational Safety and Health (NIOSH) recommends limiting operating-room concentration of nitrous oxide to ______ ppm: A. 10 B. 25 C. 50 D. 100
B. NIOSH recommends limiting operating-room concentration of nitrous oxide to 25 ppm. Minimizing operating-room pollution is important to prevent health-related effects in health-care providers. Waste-scavenging systems are utilized to decrease operating-room pollution
A 26-year-old male patient with Alport syndrome requires hemodialysis (every third day) and presents for an arteriovenous fistula creation. His last dialysis treatment was yesterday. Patient requests general anesthesia for this procedure. Which of the following drugs will have a prolonged duration of action? A. Fentanyl B. Neostigmine C. Atracurium D. Methadone
B. Succinylcholine, atracurium, and cis-atracurium have theoretical advantages because their elimination occurs via plasma cholinesterases and Hofmann degradation, respectively, mostly independent of renal or hepatic function. Fentanyl and methadone are also considered relatively safe in renal failure as they have no active metabolites. Methadone has limited plasma accumulation in renal failure as it is primarily eliminated in the feces. In terms of reversal agents, renal excretion accounts for approximately 50% of the clearance of neostigmine and approximately 75% of elimination of edrophonium and pyridostigmine. Renal failure allows some protection against residual neuromuscular blockade because renal elimination half times of anticholinesterase drugs is prolonged.
For the removal of a complex spinal cord tumor, the surgeon expresses concern of damage to the anterior spinal artery. The monitoring that would be helpful to determine viability of the anterior spinal cord intraoperatively would include: A. Electroencephalography B. Motor-evoked potentials C. Somatosensory-evoked potentials D. Bispectral index or Sedline monitoring
B. The corticospinal tracts responsible for motor function travel along the anterior spinal cord, and can be monitored using motor-evoked potentials. Sensory tracts, on the other hand, travel along the posterior spinal cord, and can be monitored using somatosensory-evoked potentials. Electroencephalography is commonly used to measure cerebral activity during neurovascular surgeries, such as carotid endarterectomies, looking for decreased cerebral blood flow. Bispectral index or Sedline monitoring is somewhat controversial, but is used to monitor the adequacy of depth of anesthesia.
During epidural placement using a midline approach, the epidural needle penetrates all the following anatomical layers, except A. Ligamentum flavum B. Subarachnoid membrane C. Supraspinous ligament D. Intraspinous ligament
B. To perform an epidural block, the needle passes through several layers, including skin, subcutaneous tissue, supraspinous ligament, intraspinous ligament, and ligament flavum. To perform a spinal anesthesia, the needle goes deeper to penetrate the dura and frequently the subarachnoid membrane.
Variable bypass vaporizers should be located: A. Between the common gas outlet (upstream) and the flowmeters (downstream) B. Between the flowmeters (upstream) and the common gas outlet (downstream) C. Between the gas pipeline and the flowmeters D. Inside the circle system
B. Vaporizers are located between the flowmeters (upstream) and the common gas outlet (downstream). In other words, vaporizers are located outside the circle system. This decreases the likelihood of delivery of high vapor concentrations when using the oxygen-flush valve.
The risk of complication from pulmonary artery catheter placement is less than A. 0.05% B. 0.5% C. 5% D. 15%
B. While the incidence of complications is infrequent, some of the complications can carry severe morbidity and mortality risks. In addition to universal complications associated with central line placement, some additional pulmonary artery catheter complications include dysrhythmias (most common), catheter knotting, cardiac valve injury, pulmonary artery rupture, development of complete heart block in a patient with preexisting left bundle branch block, pulmonary thromboembolism or air embolism, bacteremia, endocarditis, and sepsis
True statement about autonomic hyperreflexia is: A. Lesions below T10 is responsible for the reflex B. It can be treated with deep general anesthetic C. It is associated with vasoconstriction above the site of injury D. It can be provoked by thermal stimulation
B. Autonomic hyperreflexia is seen in patients with spinal cord injury at or above T6. It is characterized by acute generalized sympathetic hyperactivity in response to a triggering stimulus. The triggering stimulus can be any stimulus occurring below the level of the lesion, and is most commonly a distension of hollow viscera (bowel or bladder). Clinical signs include severe hypertension, bradycardia, arrhythmias, profuse sweating, vasodilation above the level of lesion, and pallor and vasoconstriction below the level of lesion. Antihypertensives may have to be utilized to treat the hypertension. Spinal anesthesia (not preferred because of technical difficulty and unpredictable level) or deep general anesthesia has been used in preventing autonomic hyperreflexia.
A 45-year-old healthy male is scheduled for bilateral elbow open reduction interior fixation secondary to a motor vehicle accident. Successful bilateral supraclavicular blocks were planned and performed under ultrasound guidance, with 20 mL 0.5% ropivacaine injected for each block on each side. In the operating room, the patient is receiving 25 μg/kg/min of a propofol infusion and oxygen via a non-rebreather bag. The patient also received 2 mg of midazolam, but no opioids. Thirty minutes after incision, the patient is experiencing progressive respiratory depression, and the oxygen saturation decreases from 100% to 85%. The most likely diagnosis is : A. Local anesthetic systemic toxicity (LAST) B. Dysfunction of the diaphragm (diaphragm palsy) C. Methemoglobinemia D. Aspiration pneumonia
B. Bilateral supraclavicular blockade can significantly increase the risk of symptomatic phrenic nerve palsy. Methemoglobinemia can happen in patients with certain local anesthetics, but usually not from ropivacaine administration. LAST can occur from administration of toxic doses of any local anesthetic, but is most often an acute event from systemic administration.
Of the choices listed, which may make caudal anesthesia difficult in the elderly? A. Only children have a sacral hiatus B. Calcification of the sacrococcygeal ligament. C. Intrathecal injection risk is too high. D. Caudal blocks are only partially effective in adults..
B. Calcification of the sacrococcygeal ligament.
When shining a light into a patient's eye during a neurological exam, which cranial nerve is being tested for a pupillary reflex? A. Cranial nerve X B. Cranial nerve III C. Cranial nerve II D. Cranial nerve IV
B. Cranial nerve III Motor control of the iris- regulation of the size of the pupil comes from cranial nerve 3 also called occulomotor nerve.
All of the following are examples of restrictive airway disease except. A. Negative pressure pulmonary edema B. Cystic fibrosis C. Sarcoidoisis D. Flail chest.
B. Cystic Fibrosis
After placing a central line in an unstable patient in the ICU, you notice the initial CVP tracing shows very prominent C-V waves. If an echocardiogram was then obtained, you might expect to find: A. Cardiac tamponade B. Significant tricuspid regurgitation C. Atrial fibrillation D. AV dissociation
B. During systole in a patient with tricuspid regurgitation, part of the ejected volume flows backward into the atrium. Instead of seeing a small C wave that normally represents the bulging of the tricuspid valve, a much larger C wave would be seen as blood flows retrograde into the right atrium and toward the transducer. This retrograde blood flow would continue throughout the systole, and would, therefore, also increase the V wave size, since this is a systolic component of the CVP trace. During cardiac tamponade, there will be elevated pressures throughout the entire waveform, as well as loss of the Y descent. In patients with atrial fibrillation, there will be a loss of the A wave, since there is no longer a uniform atrial contraction, and an overall increase in the C wave size, since filling pressures elevate to compensate and improve ventricular filling. With AV dissociation, there are large and exaggerated A waves (often called "cannon" A waves), which represent atrial contraction against a closed tricuspid valve. 19. A. See the answer explanation of Question 18. It would be highly unlikely to have
An absolute contraindication for electroconvulsive therapy (ECT) is A. Hypertension B. Pheochromocytoma C. Aortic aneurysm D. Stroke
B. ECT is commonly used for treatment of refractory major depression. It involves using electricity to shock one or both cerebral hemispheres to induce a seizure lasting 30 to 60 seconds. Contraindications to ECT include pheochromocytoma, recent myocardial infarction (<3 months), recent stroke (<1 month), intracranial mass or increased ICP, angina, poorly controlled heart failure, significant pulmonary disease, bone fractures, severe osteoporosis, pregnancy, glaucoma, and retinal detachment.
Select the FALSE statement. A. If a Magill forceps is used for a nasotracheal intubation, the right nares is preferable for insertion of the nasotracheal tube B. Extension of the neck can convert an endotracheal intubation to an endobronchial intubation . C. Bucking signifies the return of the coughing reftex D. Postintubation pharyngitis is more likely to occur in females E. Stenosis becomes symptomatic when the adult tracheal lumen is reduced to less than 5 mm.
B. Extension of the neck can convert an endotracheal intubation to an endobronchial intubation. Complications of tracheal intubation can be divided into those associated with direct laryngoscopy and intubation of the trachea, tracheal tube placement, and extubation of the trachea. The most frequent complication associated with direct laryngoscopy and tracheal intubation is dental trauma. If a tooth is dislodged and not found, radiographs of the chest and abdomen should be taken to determine whether the tooth has passed through the glottic opening into the lungs. Should dental trauma occur, immediate consultation with a dentist is indicated. Other complications of direct laryngoscopy and tracheal intubation include hypertension, tachycardia, cardiac dysrhythmias, and aspiration of gastric contents. The most common complication that occurs while the endotracheal tube is in place is inadvertent endobronchial intubation. Flexion, not extension, of the neck or change from the supine to the head-down position can shift the carina upward, which may convert a mid-tracheal tube placement into a bronchial intubation. Extension of the neck can cause cephalad displacement of the tube into the pharynx. Lateral rotation of the head can displace the distal end of the endotracheal tube approximately 0.7 cm away from the carina. Complications associated with extubation of the trachea can be immediate or delayed. The two most serious immediate complications associated with extubation of the trachea are laryngospasm and aspiration of gastric contents. Laryngospasm is most likely to occur in patients who are lightly anesthetized at the time of extubation. If laryngospasm occurs, positive-pressure mask-bag ventilation with 100% 02 and forward displacement of the mandible may be sufficient treatment. However, if laryngospasm persists, succinylcholine should be administered intravenously or intramuscularly. Pharyngitis is another frequent complication after extubation of the trachea. This complication occurs most commonly in females, presumably because of the thinner mucosal covering over the posterior vocal cords compared with males. This complication usually does not require treatment and spontaneously resolves in 48 to 72 hours. Delayed complications associated with extubation of the trachea include laryngeal ulcerations, tracheitis, tracheal stenosis, vocal cord paralysis, and arytenoid cartilage dislocation.
A 56-year-old woman is scheduled for a right total knee replacement. She has a medical history of hypertension, diabetes mellitus, obesity, and is status post L1-L5 vertebral fusion. The regional anesthetic technique that will provide her the most optimal perioperative pain management is A. A femoral nerve block and an epidural B. A femoral and proximal sciatic nerve block C. Both a femoral and popliteal sciatic nerve block D. A sciatic nerve block and a spinal
B. Femoral and proximal sciatic nerve block together can often provide for excellent perioperative pain control and can facilitate physical therapy with a reduced incidence of interference with ambulation. These peripheral regional techniques can be particularly useful in patients with difficulty or contraindications to neuraxial blockade.
7. A 71-year-old female develops a severe case of diarrhea with multiple loose bowel movements since awakening this morning. When she arrives preoperatively for her surgery, an arterial blood gas (ABG) is obtained. The most likely finding would be A. pH = 7.30, PaCÓ = 50, PaÓ = 60, HCǑ − = 24 B. pH = 7.35, PaCÓ = 32, PaÓ = 85, HCǑ − = 18 C. pH = 7.45, PaCÓ = 30, PaÓ = 80, HCǑ − = 28 D. pH = 7.40, PaCÓ = 45, PaÓ = 85, HCǑ − = 15
B. Gastrointestinal secretions, including diarrhea and intestinal fistulas, are rich in bicarbonate and, therefore, losses will cause a metabolic acidosis. However, respiratory compensation for metabolic processes will occur almost immediately by increasing ventilation to blow off CÓ to reduce the acidosis, effecting change in as quick as 15 to 30 minutes. Therefore, one would expect ABG findings of a metabolic acidosis with full respiratory compensation.
The most correct statement regarding the appropriate use of ultrasound equipment during performance of regional anesthesia is A. Higher frequency ultrasound probes are used for deeper penetration B. High-frequency ultrasound probes provide for higher image resolution C. Liner array probes are typically used for imaging deeper anatomical structures D. The curvilinear probe is designed to best image superficial structures.
B. High-frequency ultrasound probes are typically manufactured with a liner probe design and provide high image resolution used for superficial anatomical structures. Low-frequency ultrasound probe equipment is typically produced with a curvilinear probe design and reveals a lower image resolution, but is used for visualizing deeper anatomical structures secondary to better penetration
Which of the following is the most useful in improving neurologic oUlcome after cardiac arrest? A. Steroids B. Hypothermia C. Barbiturates D. Ibuprofen E. Calcium
B. Hypothermia Global brain ischemia occurs when there is an inadequate supply of oxygen and nutrients to the entire brain. Global ischemia may be stratified into incomplete (e.g., systemic shock with persistent low blood now to the brain) or complete (e.g., cardiac arrest). In contrast, focal brain ischemia occurs when there is ischemia to only a portion of the brain (e.g., classic stroke). Although corticosteroids are thought to possess antioxidant properties, investigators evaluating their effectiveness during cardiac arrest have reported either no improvement or a worsening of neurologic outcome. Worsening of outcome is thought to be due to corticosteroid-induced hyperglycemia. During focal brain ischemia, barbiturates provide neuronal protection by decreasing cerebral metabolism (i.e., EEG activity) and redistributing regional CBF. However, because the EEG becomes isoelectric (i.e., maximal depression of electrical activity and metabolism) within 20 seconds of cardiac arrest and there is no CBr to redistribute, studies demonstrating barbiturate-mediated brain protection during or after cardiac arrest are lacking. Use of ibuprofen for brain protection has not been demonstrated in cardiac arrest patients. During ischemia, calcium accumulates within neurons and contributes to irreversible cell death. Thus, in the setting of a disrupted blood brain barrier, intravenous calcium may worsen postischemic neurologic outcome. Hypothermia, at the time of either focal or global brain ischemia, has consistently been demonstrated to provide brain protection during cardiac arrest. The mechanisms of hypothermia-mediated brain protection are discussed in the following reference.
Signs and symptoms of raised intracranial hypertension include all the following, except : A. Hypertension B. Tachycardia C. Bradycardia D. Irregular respiration
B. Increased intracranial pressure (ICP) can lead to altered mental status, intractable vomiting, and focal or global neurological deficits. Clinical signs include hypertension, bradycardia, irregular respiration, and pupillary changes (papilledema may be seen on fundoscopy). Cushing triad consists of raised ICP, hypertension, and bradycardia
Anesthetic management of a patient with multiple sclerosis (MS) includes A. Avoiding hypothermia B. Avoiding hyperthermia C. Spinal anesthesia is safe D. Use of succinylcholine can result in hypokalemia
B. MS is characterized by progressive demyelination in the brain and spinal cord. Stress, anesthesia, and surgery can have detrimental effects on the course of the disease. Elective surgery should be avoided in acute relapse of MS. Regarding the effect of anesthetic technique on MS, spinal anesthesia can exacerbate MS symptoms, epidural anesthesia usually does not affect MS, succinylcholine should be avoided to prevent hyperkalemia, and hyperthermia should be avoided as an increase in temperature may block nerve conduction. Advanced MS may be associated with autonomic dysfunction.
Typical mixed venous oxygen tension in a healthy adult is A. 25 mm Hg B. 40 mm Hg C. 55 mm Hg D. 75 mm Hg
B. Mixed venous oxygen tension can provide valuable information on the balance between oxygen consumption and delivery. Typical mixed venous oxygen tension in a healthy adult is 40 mm Hg, yielding a saturation of approximately 75%. Reduction in oxygen delivery can be due to a reduction in oxygen content per deciliter leaving the left ventricle, or a reduction in overall cardiac output. Increased oxygen consumption (low mixed venous oxygen) occurs during periods of elevated metabolic states, such as during vigorous exercise or sepsis
The principal site of action of local anesthetics placed into the epidural space is the: A. Spinal cord B. Nerve roots C. Epidural space D. Subarachnoid space
B. Nerve roots. Major site of action of neuraxial blockade takes place on the nerve roots. Local anesthetics act on nerve roots in the subarachnoid space in the case of a spinal blockade and on the nerve roots in the epidural space in the case of epidural anesthesia.
Administration of large volumes of normal saline can lead to: A. A metabolic alkalosis B. A hyperchloremic-induced nongap metabolic acidosis C. An anion gap lactic acidosis D. None of the above
B. Normal saline (0.9% NaCl) is slightly hypertonic and contains more chloride than extracellular fluid. Administration of large volumes of normal saline solution can lead to a hyperchloremic non-anion gap metabolic acidosis. Administration of large amounts of lactated Ringer solution may result in a metabolic alkalosis because of increased bicarbonate production from the metabolism of lactate.
Total normal cerebral blood flow (CBF) is A. 25 mL/100 g/min B. 50 mL/100 g/min C. 100 mL/100 g/min D. 150 mL/100 g/min
B. Normal total CBF is about 50 mL/100 g/min. CBF below 20 mL/100 g/min is associated with cerebral ischemia. CBF is modulated by various factors, which include PaCÓ, PaÓ, blood pressure, intracranial pressure, etc.
When evaluating flow at a specific point during echocardiography, you would use: ' A. Continuous-wave Doppler B. Pulse-wave Doppler C. Color Doppler D. Pulse-wave or continuous-wave Doppler
B. Pulse-wave Doppler is used to capture flow at a specific point. During pulsewave Doppler, a single crystal is used to both emit and receive ultrasound energy, and the location of the signal can be calculated. Continuous-wave Doppler, on the other hand, uses two separate crystals to send and receive ultrasound energy. This allows the echo machine to detect higher velocities and energy shifts; however, the exact location of the signal cannot be determined. Color-wave Doppler is used to examine regurgitant lesions.
An 80-year-old female comes to the ER with closed distal radial fracture. On further questioning, she gives a history of stroke about 2 weeks ago. How long should one wait before it can be assumed that her risk of perioperative stroke is same as a healthy 80-year-old? A. 6 days B. 6 weeks C. 6 months D. 6 years
B. Regional blood flow and metabolic rate are normal after 2 weeks following a stroke. Alterations in CÓ responsiveness and blood-brain barrier abnormalities require more than 4 weeks to be corrected. Thus, most clinicians postpone elective surgery for at least 6 weeks following stroke.
While performing a femoral nerve block guided with a nerve stimulator, you observe a strong sartorius muscle twitch that disappears at 0.2 mA. What does this mean and how should you proceed further? A. The stimulating block needle tip is in the correct position, and the local anesthetic can be injected B. The needle tip is likely superficial to the femoral nerve, and the block needle needs to be readjusted (twitch may not be from stimulation of the femoral nerve) prior to local anesthetic injection C. Sartorius muscle twitch indicates that the needle tip is in the correct location, but you need to get closer to the nerve as 0.2 mA stimulus is too high D. The block needle needs to be repositioned more medially, and a paresthesia must be elicited prior to local anesthetic injection
B. Sartorius muscle twitch could be secondary to stimulation of a small branch from the femoral nerve that innervates the sartorius muscle or secondary to direct muscle stimulation. The femoral nerve is usually positioned more lateral and deeper to this small branch that originates from the femoral nerve which innervates the sartorius muscle.
Sciatic nerve blockade provides sensory loss of the A. Anterior and lateral thigh B. Posterior thigh and majority of the leg below the knee C. Medial and posterior thigh D. Medial leg below the knee
B. Sciatic nerve blockade provides sensory loss to the posterior thigh by blocking the posterior cutaneous nerve along with everything below the knee, except for the medical lower leg, which is innervated by the saphenous nerve.
The afferent input for somatosensory-evoked potentials is carried by which spinal cord tract A. Corticospinal B. Dorsal columns C. Spinothalamic D. Spinocerebellar
B. Somatosensory-evoked potentials are transmitted through the following pathway: peripheral stimulus → peripheral nerve → dorsal root ganglia → first-order fibers in the ipsilateral posterior column to dorsal column nuclei → second-order fibers crossing to the opposite side → medial lemniscus to the thalamus → third-order fibers continuing to the frontoparietal sensory-motor cortex.
While performing an ultrasound-guided axillary nerve block along with a nerve stimulator, your needle tip is imaged inferior to the pulsating axillary artery, and you see evidence of flexion of fourth and fifth digits. The stimulating needle tip is in closest proximity to which of the following peripheral nerve branches of the brachial plexus? A. Median B. Ulnar C. Musculocutaneous D. Radial
B. Some anatomical variation can exist, but the ulnar nerve is frequently positioned inferior to the axillary artery. Stimulation of the ulnar nerve will cause wrist flexion, flexion of the fourth and fifth digits, and thumb adduction.
A 26-year-old male patient with Alport syndrome requires hemodialysis (every third day) and presents for an arteriovenous fistula creation. His last dialysis treatment was yesterday. Patient requests general anesthesia for this procedure. Which of the following drugs will have a prolonged duration of action? A. Fentanyl B. Neostigmine C. Atracurium D. Methadone
B. Succinylcholine, atracurium, and cis-atracurium have theoretical advantages because their elimination occurs via plasma cholinesterases and Hofmann degradation, respectively, mostly independent of renal or hepatic function. Fentanyl and methadone are also considered relatively safe in renal failure as they have no active metabolites. Methadone has limited plasma accumulation in renal failure as it is primarily eliminated in the feces. In terms of reversal agents, renal excretion accounts for approximately 50% of the clearance of neostigmine and approximately 75% of elimination of edrophonium and pyridostigmine. Renal failure allows some protection against residual neuromuscular blockade because renal elimination half times of anticholinesterase drugs is prolonged.
Which of the following approaches to blockade of the brachial plexus is associated with the highest incidence of a pneumothorax? A. Interscalene and axillary approaches B. Supraclavicular and interscalene approaches C. Infraclavicular and axillary approaches D. Axillary and interscalene approaches
B. Supraclavicular approach to blockade of the brachial plexus carries a high risk of pneumothorax followed by the interscalene approach. This pneumothorax risk has decreased and is believed to be secondary to the more frequent use of ultrasoundguided regional anesthesia. Now the supraclavicular approach to blockade of the brachial plexus is commonly performed with ultrasound guidance.
A supraclavicular approach for brachial plexus blockade would deposit local anesthetics at which of the following anatomical levels of the plexus? A. Branches B. Trunks/Divisions C. Cords D. Roots
B. Supraclavicular blockade of the brachial plexus is often referred to as the "spinal anesthesia" of the upper extremity. It provides anesthesia of the brachial plexus distal to the roots and proximal to the cords of the plexus. There has been an increased practice of performing the supraclavicular approach to blockade of the brachial plexus secondary to the introduction of ultrasound into clinical practice as anesthesiologists can now appreciate a decreased incidence of pneumothorax under real-time ultrasound guidance.
The most incorrect statement regarding transversus abdominis plane (TAP) block is A. TAP blocks can provide analgesia following hernia repair surgeries B. TAP blocks can often alleviate both somatic and visceral pain C. One potential complication includes liver injury D. Unilateral TAP blocks never cross over the midline
B. TAP blocks can provide analgesia for peripheral somatic pain of the abdomen and can be associated with a low yet potential risk of bowel perforation and liver injury. For midline ventral hernia surgery, performing bilateral TAP blocks are often needed. TAP blocks do not cover crappy, visceral pain
The accuracy of pulse oximetry can be significantly reduced by all of the following, except: A. Intravenous bolus of methylene blue B. Intravenous bolus of heparin C. Severe acidosis D. Low blood flow
B. The accuracy of pulse oximetry can be affected by many factors. These include but are not limited to low blood flow conditions, patient movement, ambient light, dysfunctional hemoglobin molecules, dyes such as methylene blue and indigo carmine, and altered relationships in the hemoglobin dissociation curve (severe acidosis). Intravenous heparin bolus is not known to distort the accuracy of pulse oximetry.
While performing an axillary brachial plexus block, all of the following nerves are spared, except A. Musculocutaneous nerve. B. Ulnar nerve. C. Lateral brachial cutaneous nerve. D. Medial brachial cutaneous nerve.
B. The musculocutaneous and medial brachial cutaneous nerves branch from the brachial plexus at a more proximal location than can be consistently anesthetized with an axillary nerve block approach of the brachial plexus. Therefore, these nerve branches need to be blocked separately if they innervate the planned surgical area. The lateral brachial cutaneous nerve is a branch of musculocutaneous nerve
You successfully perform a right supraclavicular nerve block for a right wrist open reduction interior fixation. You are called to the post-anesthesia care unit 2 hours later because the patient is complaining of pain on the back of the wrist, which extends distal to the index, middle, and ring fingers on the dorsal surface of the hand. You consent the patient to perform a terminal branch nerve block to supplement the initial block. The nerve that would be needed to be blocked is A. Median nerve B. Radial nerve C. Infraclavicular nerve D. Interscalene nerve
B. The sensory distribution on the dorsal surface of the hand described in the question matches the innervation provided by the radial nerve. Therefore, a terminal nerve block anywhere along the distribution of the radial nerve proximal to the wrist would be an appropriate place to supplement the initial brachial plexus block
The storage time for packed red blood cells at temperatures of 1 to 6°C is A. 7 to 10 days B. 21 to 35 days C. 60 to 80 days D. 120 days
B. The storage time (70% viability of transfused erythrocytes 24 hours after transfusion) is 21 to 35 days, depending on the storage medium. Changes that occur in blood during storage reflect the length of storage and the type of preservative used.
Select the correct order from greatest to least for the sensitivity of the following neurophysiologic monitoring techniques to volatile anesthetics (SSEP [somatosensory evoked potential]; VEP [visual evoked potential]; BAEP [brainstem auditory evoked potential]). A. SSEP > VEP > BAEP B. VEP> SSEP > BAEP C. BAEP > VEP > SSEP D. SSEP> BAEP > YEP E. SSEP = VEP > BAEP
B. VEP> SSEP > BAEP Many of the commonly used anesthetic agents can alter the characteristics of evoked potential waveforms. In general, volatile anesthetics cause a dose-dependent increase in the latency and decrease in the amplitude of SSEPs. BAEPs are the most resistant to the depressant effects of volatile anesthetics, whereas VEPs are the most sensitive. In general, up to I MAC of isoflurane, enfturane, or halothane is compatible with adequate SSEP monitoring
When performing the oscillometric method to measure blood pressure, for example, when you do not have a stethoscope or automated blood pressure cuff, it is important to remember that you will not be able to measure the : A. Systolic blood pressure B. Diastolic blood pressure C. Mean arterial pressure D. Diastolic or mean arterial blood pressure
B. When using the oscillometric method to measure blood pressure, the cuff is inflated until no oscillations on the sphygmomanometer are seen. The cuff is then slowly deflated until oscillations are seen, which represents the systolic blood pressure. As the cuff continues to be deflated, you note the point where maximal oscillations occur. This point of maximal oscillation represents the mean arterial pressure. It is not possible to measure a diastolic blood pressure with the oscillometric method.
Loss of deep tendon reflexes is most likely a consequence of: A. Hypomagnesia B.. Hypermagnesia C. Hypocalcemia D. Hypercalcemia
B.. Hypermagnesia Loss of deep tendon reflexes is the 1st sign of a high magnesium level.
Factors increasing the affinity of hemoglobin for oxygen include: (Select 2) A- increased carbon dioxide levels B-increased 2,3-DPG levels C- increased pH D- the presence of fetal hemoglobin E- increased body temperature F- the presence of hemoglobin-S
C, D -increased pH, presence of fetal hemoglobin Factors that increase the affinity of hemoglobin for oxygen would cause a leftward shift of the hemoglobin dissociation curve and a decrease in the P50. These factors include alkalosis, decreased CÓ levels, and decreased 2,3-DPG levels. Hemoglobin-S, found in patients with sickle cell disease, has a decreased affinity for oxygen. Fetal hemoglobin, however, has an increased affinity for oxygen to help in oxygen transfer from the mother to the fetus.
Pathophysiologic changes associated with ALI/ARDS include: (Select 2) A-hypoxemia responsive to oxygen therapy B-increased static compliance of the chest wall C-diffuse alveolar edema D-high dead space fraction E-reduced mean pulmonary artery pressure F-decreased intrapulmonary shunt
C,D -diffuse alveolar edema, high dead space fraction ALI and ARDS are syndromes of acute, hypoxemic respiratory failure, with resulting increased lung permeability and diffuse alveolar edema. Clinically, ARDS and ALI are characterized by reduced static thoracic (lung and chest wall) compliance and severe impairment of gas exchange, including high intrapulmonary shunt and dead space fraction with pulmonary hypertension. The high level of intrapulmonary shunt results in hypoxia, which is relatively unresponsive to oxygen therapy
Laminar flow in the airway occurs in the: (Select 2) A-trachea B-main stem bronchi C-terminal bronchiole D-3rd generation bronchus E-respiratory bronchiole
C,E- terminal bronchiole, respiratory bronchiole Flow in the larger airways is mostly turbulent. Laminar flow normally occurs only distal to small bronchioles (< 1mm). The Reynolds number is used to predict the type of airway flow; a low Reynolds number (< 1000) is associated with laminar flow, whereas a high value (> 1500) is associated with turbulent flow.
A 46-year-old male is scheduled for an emergent laparotomy for small bowel obstruction. His history is complicated by the acute onset of hepatitis B four days earlier and he presents with significant scleral jaundice. The perioperative mortality in this patient is approximately: A-2% B- 5% C- 10% D- 25%
C- 10% Patients with acute hepatitis should have elective surgery postponed until the acute hepatitis has resolved. Studies indicate increased perioperative morbidity (12%) and mortality (10% with laparotomy) during acute hepatitis.
The National Institute for Occupational Safety (NIOSH) recommends limiting the operating room concentration of nitrous oxide to: A- 0.5 ppm B- 5 ppm C- 25 ppm D- 50 ppm
C- 25 ppm NIOSH recommends limiting the room concentration of nitrous oxide to 25 ppm and halogenated agents to 2 ppm (0.5 ppm if nitrous oxide is also being used.
Bronchial Blockers: A- Are placed without a fiberoptic bronchoscope. B- Permit ventilation of the isolated lung. C- Can be used in children. D- Are contraindicated when nasotracheal intubation is required.
C- Can be used in children. Brochial blockers are used in patient's requiring lung separation. It can be used in Children < 12 years of age. Requring nasotracheal intubation,. Having a tracheostomy. Having a single lumem ETT in place. Avoiding having to change a DLT to a SLT after surgery.
What is the most significant effect of sevoflurane at 0.1 MAC? A- Skeletal muscle weakness B- Myocardial depression C- Impaired response to hypoxia. D- Impaired response to hypercarbia.
C- Impaired response to hypoxia. All inhaled anesthestics, including nitrous impair th peripheral chemoreceptors response to acute hypoxia for up to several hours after anesthesia.
What is the most likely cause of death related to liposuction? A- Local anesthetic systemic toxicity B- Fluid overload C- Pulmonary embolism D- Epinephrine overdose
C- Pulmonary embolism Liposuction is associated with a mortality rate of 19.1 per 100,000 procedures. Of these, pulmonary embolism is the most common cause of death. Other causes of mortality include perforation of the abdominal viscera, infection, hemorrhage, and anesthesia related causes. Remember that the maximum dose of lidocaine for liposuction is 55 mg/kg.
When is the patient with coronary artery disease at greatest risk for a myocardial infarction. A- The morning of surgery. B- During surgery. C- Within 2 days after surgery. D- Within 1 week after surgery.
C- Within 2 days after surgery. Most perioperative MI's are undiagnosed. According to the POISE study, most occur with 48 hours after surgery. Of these 65.5 % did not report any symptoms.
Dextran 40 has been shown to improve microcirculation by: A- reducing blood density B-increasing blood density C- decreasing blood viscosity D- increasing blood viscosity
C- decreasing blood viscosity Dextran 40 has been shown to improve microcirculation presumably by decreasing blood viscosity thereby improving laminar flow in the microcirculatory beds. Both Dextran 40 and Dextran 70 possess antiplatelet effects and may interfere with blood typing.
Sensory innervation of the trachea and larynx below the vocal cords is supplied by the: A- internal laryngeal nerve B- external laryngeal nerve C-recurrent laryngeal nerve D- glossopharyngeal nerve
C- recurrent laryngeal nerve The vagus nerve provides sensation to the airway below the epiglottis. The superior laryngeal branch of the vagus divides into an external (motor) and internal (sensory) laryngeal nerve that provide sensory supply to the larynx between the epiglottis and the vocal cords. Another branch of the vagus, the recurrent laryngeal nerve, innervates the larynx below the vocal cords and trachea.
During the administration of general anesthesia for a radical prostatectomy, the rhythm strip below is obtained. The most appropriate therapeutic measures at this time would include: A- initiation of a nitroglycerine infusion B-administration of metoprolol C- requesting the use of a bipolar cautery D-engage the artifact filter on the ECG monitor
C- requesting the use of a bipolar cautery This rhythm strip indicates a paced rhythm with clearly visible pacer spikes. Electrical interference from the electrocautery can be interpreted as myocardial activity and can suppress the pacemaker generator. The use of a bipolar cautery will reduce the electrical interference produced; if that is not possible, then pure cut is better than "blend" or "coag."
After the unintentional intravascular injection of bupivacaine during an attempted caudal, a 3-month-old 5 kg full term boy develops local anesthetic toxicity. Resuscitation is initiated with chest compressions, ventilation, and epinephrine. What is the MOST appropriate dose of 20% intralipid? A-1 ml IV bolus B-2.5 ml IV bolus C-10 ml IV bolus D-20 ml IV bolus
C-10 ml IV bolus The most appropriate management is a 1.5 mL/kg bolus of 20% intralipid followed by 0.25 mL/kg/min according to Guy Weinberg [founder of LipidRescue]. In older textbooks, some authors have recommended 4 ml/kg but the dose recommended by Dr Weinberg and ASRA is 1.5 ml/kg. Propofol is NOT an appropriate substitute
According to the 2010 American Society of Regional Anesthesia (ASRA) guidelines, epidural catheter placement in obstetric patients should be delayed for at least how long after administration of a therapeutic dose of low-molecular weight heparin? A-6 hours B-12 hours C-24 hours D-48 hours
C-24 hours Pregnancy is a state of relative hypercoagulability. Pregnant patients needing anticoagulation are often treated with low-molecular weight heparin (LMWH) due to its efficacy, maternal safety, ease of administration, and lack of placental transfer to the fetus. Anticoagulated patients are at increased risk for the development of epidural and spinal hematoma following neuraxial anesthetics. Although there is no definitive data linking absolute time since LMWH administration with the development of epidural and spinal hematoma, consensus guidelines have been created in an attempt to decrease the risk of this catastrophic complication. Patients receiving higher therapeutic doses of LMWH are at increased risk compared to patients receiving lower prophylactic doses of LMWH. ASRA guidelines state that neuraxial placement should occur no sooner than 24 hours following a therapeutic dose of LMWH. Neuraxial placement should occur no sooner than 10-12 hours following a prophylactic dose of LMWH.
The National Institute for Occupational Safety (NIOSH) recommends limiting the operating room concentration of nitrous oxide to: A-0.5 ppm B-5 ppm C-25 ppm D-50 ppm
C-25 ppm NIOSH recommends limiting the room concentration of nitrous oxide to 25 ppm and halogenated agents to 2 ppm (0.5 ppm if nitrous oxide is also being used).
What is the maximal reduction in the cerebral metabolic requirement for oxygen (CMRÓ) achievable exclusively through the use of high-dose barbiturates? A-10% B-25% C-50% D-75% E-90%
C-50% At best, high-dose barbiturates can only reduce the CMRÓ by approximately 50%. Barbiturates, as most anesthetics, are only able to reduce that proportion of the CMRÓ that is responsible for electrical activity. As electrical activity accounts for only about 50% of the CMRÓ, barbiturates can only reduce it by an equivalent amount. Further reductions in CMRÓ are really only possible with hypothermia.
The phrenic nerves arise from the: A-nucleus ambiguous:' B-C1 - C2 nerve roots C-C3 - C5 nerve roots D-C6 - T2 nerve roots
C-C3 - C5 nerve roots The phrenic nerves arise from the C3 - C5 nerve roots. Unilateral phrenic nerve palsy only modestly reduces most indices of pulmonary function (about 25%). Bilateral phrenic nerve palsies produce more severe impairment, but accessory muscles may maintain adequate ventilation. Cervical cord injuries above C5 are incompatible with spontaneous ventilation.
Two days after resection of a brain tumor through a right frontal craniotomy, a 70-year-old man has persistent postoperative delirium with waxing-waning mental status. His sodium is 136 mEq/L and glucose is 123 mg/dL. A head CT reveals some residual pneumocephalus but no hemorrhage. Which of the following is the MOST appropriate next step in his care? A-Brain MRI B-Transcranial Doppler C-Continuous EEG monitoring D-High flow oxygen (FiÓ 1.0)
C-Continuous EEG monitoring The basic differential diagnosis for a patient with neurologic decline post-craniotomy is the following: 1. Hemorrhage 2. Tension pneumocephalus 3. Venous or arterial stroke 4. Hydrocephalus 5. Infection (urinary, pulmonary, CNS) 6. Seizures 7. Metabolic (usually sodium abnormalities). 8. Retraction injury/surgical injury. Items 1-4 are "ruled out" with a CT scan to a large extent. Infection is a consideration and should be considered, especially if the patient is on high dose dexamethasone. Surgical injury to the brain (whether avoidable or unavoidable) is possible, but generally should not produce fluctuating encephalopathy after resection of a unilateral frontal lobe tumor. Therefore, seizure activity should be highly suspected and investigated.
A patient with severe mitral stenosis presents for mitral valve replacement. Which of the following statements is LEAST correct regarding the management of this patient? A-Hemodynamic goals include increasing preload, decreasing heart rate, and maintaining SVR. B-Following PA catheter placement, one would expect to see giant V waves on pulmonary capillary wedge tracing C-During TEE examination, one would expect a mean pressure gradient >10 mm Hg calculated across the stenotic mitral valve D-Pulmonary capillary wedge pressure reflects left atrial pressure but not L.V filling pressures
C-During TEE examination, one would expect a mean pressure gradient >10 mm Hg calculated across the stenotic mitral valve. Mitral stenosis produces large A-waves on the pulmonary capillary wedge pressure tracing while mitral regurgitation produces giant V waves. All of the other statements above are true regarding the management of a patient with severe mitral stenosis.
A 5-year-old with Duchenne's muscular dystrophy presents to preoperative clinic before elective bilateral lower extremity tendon lengthening. After conducting a careful history and physical exam, which of the following is the MOST important for further preoperative assessment of this child? A-Complete blood count B-Serum electrolytes C-Electrocardiogram and echocardiogram D-Urine electrolytes
C-Electrocardiogram and echocardiogram Duchenne's muscular dystrophy (DMD) is the most common and severe form of muscular dystrophy and is an X-linked recessive disease resulting in a mutation in the dystrophin gene. DMD has effects on many organ systems in addition to skeletal muscle, including the heart. Patients frequently develop a dilated cardiomyopathy from fatty infiltration of the myocardium. This may present initially on ECG as prominent Q waves, inverted T waves, or other changes. Echocardiography will show LV wall motion abnormalities as fibrosis progresses and indicates the disease is advancing. Some form of cardiac involvement is present in up to 90% of patients; therefore, a cardiac workup is most appropriate for this patient preoperatively.
A 5-year-old with Duchenne's muscular dystrophy presents to preoperative clinic before elective bilateral lower extremity tendon lengthening. Which of the following is the MOST important for further preoperative assessment of this child? A-Complete Blood Count B-Electrolyte panel C-Electrocardiogram and echocardiogram D-History and Physical Exam
C-Electrocardiogram and echocardiogram Duchenne's muscular dystrophy (DMD) is the most common and severe form of muscular dystrophy and is an X-linked recessive disease resulting in a mutation in the dystrophin gene. DMD has effects on many organ systems in addition to skeletal muscle, including the heart. Patients frequently develop a dilated cardiomyopathy from fatty infiltration of the myocardium. This may present initially on ECG as prominent Q waves, inverted T waves, or other changes. Echocardiography will show LV wall motion abnormalities as fibrosis progresses and indicates the disease is advancing. Some form of cardiac involvement is present in up to 90% of patients; therefore, a cardiac workup is most appropriate for this patient preoperatively.
An otherwise healthy 45-year-old woman is seen at an ambulatory surgical center for release of Dupuytren's contracture. A brachial plexus block is performed using the axillary approach. Assuming that no other nerve blocks are performed, and that the axillary block successfully achieves a complete motor and sensory block in its intended distribution, which of the following motor responses in the blocked extremity would MOST likely still be present? A-Wrist flexion B-1st-5th digit adduction C-Forearm supination D-Extension of the MCP joints
C-Forearm supination At the level of the axillary artery, the brachial plexus has divided into three cords (medial, lateral, and posterior), which are named in relationship to the axillary artery. These three cords travel with the axillary artery within the axillary sheath. The musculocutaneous nerve, however, as a terminal branch of the lateral cord, travels separately and is NOT located inside the axillary sheath. Thus, it must be blocked separately from an axillary brachial plexus block. Assuming that a musculocutaneous nerve block has not been performed, we would not expect to see a motor block of the biceps muscle, and elbow flexion and forearm supination, as well as cutaneous sensation to the lateral forearm, would be intact.
A 28-year-old G1P0 woman with a history of multiple sclerosis presents to the labor and delivery unit after rupture of membranes. She is currently suffering from lower extremity sensory changes and requires an urgent cesarean section. Which of the following is the BEST option for her anesthetic? A-Combined spinal epidural anesthesia B-Epidural anesthesia C-General anesthesia D-Spinal anesthesia
C-General anesthesia Multiple sclerosis is an autoimmune disease involving demyelination of the central nervous system. The disease can either be progressive or relapsing and remitting in its course. General anesthesia is frequently thought to be the safest technique in these patients. However, they do have an increased risk of hyperkalemia following succinylcholine for muscle paralysis so this medication is best avoided. Non-depolarizing blockers are safe, although these patients may have altered sensitivity. In terms of neuraxial anesthesia, some studies have implicated spinal anesthetics in post-op disease flares that may be due to the neurotoxic effects of local anesthetics. Although the evidence is inconclusive, in patients with an active flare they are probably best avoided. Finally, in a patient with active neurologic changes epidural anesthesia is also probably also best avoided.
A 4-week-old neonate with Pierre Robin Sequence is scheduled for a direct laryngoscopy and bronchoscopy to evaluate his airway obstruction. In addition to micrognathia and airway obstruction, what additional feature defines this sequence? A-Cleft lip B-Craniosynostosis C-Glossoptosis D-Maxillary hypoplasia
C-Glossoptosis Pierre Robin sequence (PRS) is characterized by: 1) Small mandible (micrognathia); 2) Posterior displacement of the tongue (glossoptosis); and, 3) Airway obstruction. It is often, but not always associated with a cleft lip and/or palate. Pierre Robin is called a "sequence" (as opposed to a "syndrome") because everything occurs as a result of mandibular undergrowth in utero. Pierre Robin sequence may occur in isolation, but is often associated with an underlying disorder. The most common syndromes associated with PRS are Stickler syndrome, velocardiofacial syndrome, and Treacher-Collins syndrome.
A 70 kg adult man presents for emergent exploratory laparotomy after free air is seen on abdominal imaging. In addition, his serum sodium is 160 mEq/L. Which of the following is NOT true? A-A relatively higher concentration of sevoflurane will be needed for adequate anesthesia. B-The fastest rate at which his sodium should be corrected is 1.5 mEq/L/h. C-His condition would likely be worsened by administration of demeclocycline. D-Rapid correction of his sodium level could result in permanent neurologic deficit.
C-His condition would likely be worsened by administration of demeclocycline. In general, plasma sodium concentration should not be decreased faster than 0.5 mEq/L/h. Rapid correction of hypernatremia can result in permanent neurologic damage, as well as seizures and brain edema. Hypernatremia increases the minimum alveolar concentration for inhaled anesthetics. Demeclocycline is a tetracycline antibiotic that interferes with the action of ADH. By blocking ADH at its receptor, demeclocycline impairs the ability of the kidneys to concentrate urine, and therefore may worsen hypernatremia. Because of this effect, demeclocycline is used as off label treatment for SIADH. Hypernatremia increases the MAC of volatile anesthetics.
Which of the following is MOST correct regarding the most common cause of transfusion related mortality? A-It is due to clerical error B-It is due to gram-negative bacteria C-It is due to neutrophilic immune response D-It is due to platelet-mediated response
C-It is due to neutrophilic immune response Transfusion-related acute lung injury (TRALI) is the most common cause of transfusion related mortality, causing more deaths than acute hemolytic reactions from ABO blood type error. Acute hemolytic reactions are most frequently due to clerical error. Infectious complications such as sepsis occur usually from bacterial infection most common after transfusion of platelets due to storage at room temperature to maintain platelet function. Gram-negative bacteria are frequent causes of transfusion-associated sepsis as well. TRALI involves an immune response of recipient antibodies directed against donor human leukocyte antigens (anti-HLA) or human neutrophil antigens (anti-HKA) and causes an influx of neutrophils into the lungs, with subsequent activation of neutrophils and release of inflammatory mediators with the development of increased pulmonary microvascular permeability. Clinically, it is indistinguishable on chest X-ray from ARDS.
Central Retinal Artery Occlusion (CRAO) is a common cause of postoperative visual dysfunction. Which of the following statements about CRAO is MOST correct? A-An edematous optic disc is the only abnormality noted on examination of the fundus. B-It commonly associated with long (>4 hour) procedures in the prone position. C-It is normally associated with external pressure on the globe. D-It is normally bilateral. E-Most patients report some (albeit mild) improvement in visual acuity with time.
C-It is normally associated with external pressure on the globe. Although CRAO can be associated with surgery in the prone position, it is almost always associated with external pressure on the globe, regardless of patient position. Historically, the first 8 cases of perioperative CRAO were all cervical laminectomies carried out with the patient's head in the "horseshoe" headrest. This increases intraocular pressure. Thus, it is modern practice to "pin" patients in the Mayfield headrest. CRAO is unilateral 95% of the time and visual acuity does not improve. Examination reveals a pale retina and often a "cherry red" spot on the macula.
The area of myocardium most vulnerable to ischemia is the: A-left ventricular epicardium B-right ventricular epicardium C-left ventricular subendocardium D-right ventricular subendocardium
C-Left ventricular subendocardium The subendocardium of the left ventricle is most vulnerable to ischemia since this is an area of greater systolic shortening. In addition, left ventricular subendocardium perfusion is almost entirely restricted to diastole, in contrast to the subendocardium of the right ventricle that receives most of its perfusion during systole.
Which of the following would MOST likely be present after 24 hours of continued hyperventilation of an otherwise normal subject? A-PaCÓ < normal; CSF PCÓ < normal; CSF pH > normal; CBF < normal B-PaCÓ < normal; CSF PCÓ < normal; CSF pH > normal; CBF = normal C-PaCÓ < normal; CSF PCÓ < normal; CSF pH = normal; CBF = normal D-PaCÓ < normal; CSF PCÓ = normal; CSF pH = normal; CBF = normal
C-PaCÓ < normal; CSF PCÓ < normal; CSF pH = normal; CBF = normal After 24 hours of continuous hyperventilation, the patient's PaCÓ would, by definition, be low. As the blood brain barrier (BBB) is freely permeable to CÓ, the PCÓ of the CSF would also be low; however, the pH of the CSF would have normalized. This would result in normal cerebral blood flow, despite continued hyperventilation.
A 25-year-old, 90 kg man sustained a pelvic fracture in a motor vehicle accident. He has been receiving subcutaneous heparin 5,000 units twice daily for 7 days to prevent deep venous thrombosis. His last dose was 12 hours ago. He complains of terrible pain and desires and epidural for analgesia. Which of the following laboratory tests is MOST valuable prior to placing an epidural? A-Bleeding time B-INR C-Platelet count D-PTT
C-Platelet count Patients who are exposed to heparin are at risk for the development of heparin-induced thrombocytopenia. Heparin-induced thrombocytopenia occurs when IgG antibodies to platelet factor 4 are formed. Development of antibodies takes approximately 5 days. The tail of the antibody binds to the FcγIIa receptor on platelets leading to platelet activation and the formation of platelet microparticles that initiate the formation of blood clots. Thrombocytopenia occurs and the patient is at risk of thrombosis due to platelet activation.Patients receiving heparin for greater than 4 days, even with low dose (5000 IU subcutaneously twice daily) heparin, may have heparin-induced thrombocytopenia. ASRA Guidelines recommend that patients receiving heparin for longer than 4 days have their platelet count assessed prior to neuraxial blockade or removal of epidural catheters based upon Class 1C evidence.
Which of the following factors is LEAST likely to be associated with uterine atony? A-Infection B-Polyhydramnios C-Recent ketorolac D-Tocolytic therapy
C-Recent ketorolac Uterine atony is not only the leading cause of postpartum hemorrhage, but it is also the most common indication for a peripartum blood transfusion. Postpartum hemostasis involves the release of endogenous uterotonic factors, and atony results when there is failure of adequate uterus contraction after delivery. This can occur for various reasons including pre-delivery use of oxytocin (via receptor down-regulation), over-distension of the uterus due to polyhydramnios or multiple gestations, and chorioamnionitis. Tocolytic therapy relaxes uterine muscle, making it more difficult to contract after delivery. Although non-steroidal anti-inflammatory drugs can inhibit platelet function, they have minimal effect on uterine muscle tone.
A 26-year-old woman presents for laparoscopic cholecystectomy. She has a family history of sudden death and was found to have hypertrophic cardiomyopathy (HCM). Which of the following is a MOST correct regarding hypertrophic cardiomyopathy? A-Decreased systemic vascular resistance following induction can be beneficial since it increases cardiac output. B-Beta blockers will worsen stroke volume in HCM. C-Reverse Trendelenburg position during laparoscopy can worsen the systolic anterior motion of the mitral valve leaflet. D-The gradient across the aortic valve will be likely to be higher than the gradient across left ventricular outflow tract
C-Reverse Trendelenburg position during laparoscopy can worsen the systolic anterior motion of the mitral valve leaflet. Asymmetric left ventricular hypertrophy is characteristic of HCM, which can be diagnosed by echocardiography. Hypertrophy is more common in the upper interventricular septum, below the aortic valve leading to left ventricular outflow tract (LVOT) obstruction. High velocity blood flow across the LVOT during systole can result in venturi effect leading to suctioning of anterior mitral leaflet into LVOT (known as systolic anterior motion of mitral valve leaflet or SAM). Factors that increase the velocity of blood across LVOT such as decreased systemic vascular resistance, decreased preload, and increased myocardial contractility can result in SAM and a worsening in the LVOT obstruction. Since the obstruction is at level of the LVOT, the gradient is higher across LVOT than at the level of aortic valve. However, the obstruction is dynamic compared to a fixed obstruction such as aortic valve stenosis. The beneficial role of beta-blockers is due to the decreased heart rate with resultant prolongation of diastole and increased time for passive ventricular filling.
Which of the following cardiac findings during pregnancy is MOST ABNORMAL? A-Cardiomegaly on chest x-ray B-Right bundle branch block C-S4 heart sound D-Tricuspid regurgitation
C-S4 heart sound Cardiovascular changes in pregnancy revolve around the themes of increasing cardiac output and extension of blood flow to the placenta. Heart rate and stroke volume increase, while systemic vascular resistance decreases to reduce afterload and maintain a normal blood pressure. As a result of the increased volumes occupying the heart, a mild but normal increase in heart size can be seen and a third heart sound (S3) can be heard. Dilation of the heart can also cause new regurgitant murmurs, particularly tricuspid regurgitation, with a resulting systolic murmur. The dilation can temporarily alter conduction in the heart, leading to right-axis deviation and right bundle branch block. An S4 heart sound is almost always pathologic, and this holds true in pregnant women: it should be investigated fully if present.
Which of the following anesthetic techniques is associated with the LOWEST failure rate for spinal cord stimulator placement? A-General anesthesia B-Local only C-Spinal anesthesia D-Epidural anesthesia
C-Spinal anesthesia Spinal cord stimulator placement often requires both extensive surgical dissection and an awake patient for intra-operative testing to optimize the surgical result. The stimulators are placed over the spinal cord in the thoracic epidural space in most cases (the spinal cord ends at L1/2 in adults). Awake spinal cord stimulator placement is associated with a much lower failure rate. Viable anesthetic approaches include spinal anesthesia, local anesthesia with conscious sedation, and thoracic epidural anesthesia (single shot).
In which of the following clinical scenarios is the transfusion of cryoprecipitate LEAST appropriate? A-A patient with ongoing blood loss and a fibrinogen 140 mg/dl B-A trauma patient with massive hemorrhage who has received 10 units PRBCs. C-Spontaneous bleeding in a patient with Christmas D-Disease (Hemophilia B) Spontaneous bleeding in a patient with Hemophilia A
C-Spontaneous bleeding in a patient with Christmas D-Disease (Hemophilia B). Cryoprecipitate contains factor VIII, fibrinogen, vWF, and factor XIII. It does not contain factor IX, which is the missing clotting factor in hemophilia B. Although DDAVP and factor concentrates are the preferred treatment in von Willebrand's disease, cryopreciptate is an acceptable therapy if the others are not available. Hypofibrinogenemia and massive resuscitation which leads to relative fibrinogen deficiency and potentially worsened clinical bleeding are indications for administration of cryoprecipitate (or fibrinogen concentrates if available).
A 3-month-old full term boy presents for right inguinal hernia repair. If, during placement of a caudal anesthetic, the infant were unintentionally administered 1 ml/kg 0.25% bupivacaine intravenously, what would be the MOST likely INITIAL sign of cardiac toxicity? A-Supraventricular tachycardia B-Sinus tachycardia C-Ventricular tachycardia D-Third degree heart block
C-Ventricular tachycardia The most common arrhythmia observed with bupivacaine local anesthetic toxicity is a wide complex ventricular rhythm. In a dog model, bupivacaine lowered the ventricular tachycardia threshold and caused polymorphic ventricular tachycardia.
In the CVP waveform, the v wave is caused by: A-atrial contraction B-ventricular contraction C-atrial filling D-opening of the tricuspid valve
C-atrial filling In the normal CVP tracing, the a wave is due to atrial systole. The c wave coincides with ventricular contraction. The v wave is the result of atrial filling prior to the opening of the tricuspid valve. The x descent is thought to be due to the pulling down of the atrium by ventricular contraction. The y descent corresponds to the opening of the tricuspid valve.
Drugs that inhibit coagulation through direct inhibition of thrombin include: A-heparin B-warfarin C-bivalirudin D-aprotonin
C-bivalirudin Bivalirudin, hirudin, lepirudin and argatroban are anticoagulants that directly inhibit thrombin. These agents are most commonly used for cardiopulmonary bypass when heparin is contraindicated. No specific reversal agent is available and termination of effect occurs as a result of renal elimination of the drug.
Positive end expiratory pressure (PEEP): A-decreases dead space B-increases venous return to the heart C-decreases intrapulmonary shunting D-decreases extravascular lung water
C-decreases intrapulmonary shunting The major effect of PEEP is to increase FRC and tidal ventilation above the closing capacity. This results in a decrease in intrapulmonary shunting. Neither PEEP nor CPAP decrease extravascular lung water. By increasing intrathoracic pressure, PEEP decreases venous return to the heart.
During pregnancy, the minimum alveolar concentration (MAC): A-decreases until the 20th week B-increases until the 20th week C-decreases throughout the pregnancy D-increases throughout the pregnancy
C-decreases throughout the pregnancy The MAC progressively decreases during pregnancy, at term by as much as 40%. MAC returns to normal by the third day after delivery.
Pathophysiologic factors affecting the anesthetic management of patients with hypothyroidism include: A-hypernatremia B-hyperglycemia C-difficulty with intubation and airway management D-increased blood viscosity due to elevated hematocrit
C-difficulty with intubation and airway management Potential problems of hypothyroidism include hypoglycemia, anemia, hyponatremia and difficulty during intubation because of a large tongue or the presence of a goiter. Hypothermia secondary to a low metabolic rate is a common postoperative complication.
An increase in the plasma concentration and a prolongation of the elimination half-life of etomidate is seen with the concomitant administration of: A- midazolam B-rocuronium C-fentanyl D-succinylcholine
C-fentanyl Fentanyl has been shown to increase the plasma level of etomidate as well as prolong the elimination half-life of the drug.
An increase in the plasma concentration and a prolongation of the elimination half-life of etomidate is seen with the concomitant administration of: A-midazolam B-rocuronium C-fentanyl D-succinylcholine
C-fentanyl Fentanyl has been shown to increase the plasma level of etomidate as well as prolong the elimination half-life of the drug.
An increase in the plasma concentration and a prolongation of the elimination half-life of etomidate is seen with the concomitant administration of: A-midazolam B-rocuronium C-fentanyl D-succinylcholine
C-fentanyl Fentanyl has been shown to increase the plasma level of etomidate as well as prolong the elimination half-life of the drug.
A 82-year-old female is scheduled for a total hip replacement under spinal anesthesia. She has been receiving enoxaparin for deep vein thrombosis prophylaxis. Current recommendations regarding the dosing of enoxaparin state that the drug be: A-continued without interruption as scheduled B-held for 4 - 6 hours prior to the spinal anesthetic C-held for 10 - 12 hours prior to the spinal anesthetic D-held for not less than 24 hours prior to the spinal anesthetic.
C-held for 10 - 12 hours prior to the spinal anesthetic Patients receiving fractionated low-molecular weight heparin are to be considered at increased risk of spinal hematoma. Patients receiving these drugs should have the drug held for 10 - 12 hours preoperatively according to the Consensus Statement from the American Society for Regional Anesthesia and Pain Medicine.
The primary causative factor in the development of persistent pulmonary hypertension (PPH) in the neonate is: A- cystic fibrosis B-pregnancy-induced hypertension C- hypoxemia D-right-to-left shunting through a patent ductus arteriosus
C-hypoxemia Hypoxia or acidosis during the early neonatal period may predispose the infant to return to fetal circulation. This serious condition, previously known as persistent fetal circulation (PFC), is currently known as persistent pulmonary hypertension (PPH). Hypoxemia and/or acidosis promotes an increase in pulmonary vascular resistance which ultimately causes right to left shunting through the ductus arteriosus, foramen ovale, or both. Shunting causes continued hypoxemia, leading to a continued increase in pulmonary vascular resistance, and a vicious cycle ensues. Primary causes of hypoxemia in the neonate include pneumonia and meconium aspiration.
Pulmonary complications from advanced hepatic disease with cirrhosis include: A-an obstructive ventilatory defect B-respiratory acidosis C-increased intrapulmonary shunting D-increased functional residual capacity
C-increased intrapulmonary shunting Pulmonary manifestations associated with cirrhosis include: increased intrapulmonary shunting, decreased FRC, pleural effusions, restrictive ventilatory defect and respiratory alkalosis.
Factors increasing the affinity of hemoglobin for oxygen include: (Select 2) A-increased carbon dioxide levels B-increased 2,3-DPG levels C-increased pH D-the presence of fetal hemoglobin E-increased body temperature F-the presence of hemoglobin-S
C-increased pH D-presence of fetal hemoglobin Factors that increase the affinity of hemoglobin for oxygen would cause a leftward shift of the hemoglobin dissociation curve and a decrease in the P50. These factors include alkalosis, decreased CO2 levels, and decreased 2,3-DPG levels. Hemoglobin-S, found in patients with sickle cell disease, has a decreased affinity for oxygen. Fetal hemoglobin, however, has an increased affinity for oxygen to help in oxygen transfer from the mother to the fetus.
Mechanisms of renal compensation during acidosis include: A-decreased reabsorption of filtered bicarbonate B-decreased excretion of hydrogen ions C-increased production of ammonia D-increased elimination of carbon dioxide
C-increased production of ammonia The renal response to acidemia is: increased reabsorption of bicarbonate anion increased excretion of hydrogen ion in the form of titratable acids increased production of ammonia Although increased carbon dioxide elimination is a compensatory mechanism in acidemia, it is accomplished by increased alveolar ventilation.
Disodium edetate or sodium metabisulfite is added to formulations of propofol to: A-enhance drug solubility B-adjust pH C-inhibit bacterial growth D-ncrease drug potency
C-inhibit bacterial growth Current formulations of propofol contain 0.005% disodium edetate or 0.025% sodium metabisulfite to help retard the rate of microorganism growth.
Of the following, the block associated with the highest blood level of local anesthetic per volume injected is the: A-epidural block B-spinal block C-intercostal block D-caudal block
C-intercostal block Blood concentration of local anesthetic is dependent on the total volume and concentration injected. However, with the exception of airway blocks, the intercostal block results in the highest blood levels of local anesthetic per volume injected.
Of the following, the block associated with the highest blood level of local anesthetic per volume injected is the: A-epidural block B-spinal block C-intercostal block D-caudal block
C-intercostal block Blood concentration of local anesthetic is dependent on the total volume and concentration injected. However, with the exception of airway blocks, the intercostal block results in the highest blood levels of local anesthetic per volume injected.
Pathophysiologic changes associated with hypercortisolism include: (Select 2)' A-hyperkalemia B-plasma volume depletion C-metabolic alkalosis D-hypoglycemia E-hypotension F-osteoporosis G-hyponatremia
C-metabolic alkalosis, F-osteoporosis The clinical picture of hypercortisolism includes central obesity, hypertension, glucose intolerance, weakness, bruising and osteoporosis. Mineralocorticoid effects include fluid retention and hypokalemic alkalosis.
MAC-BAR is the: A-partial pressure of an anesthetic required to abolish movement in 50% of patients. B-partial pressure of an anesthetic at which subjects will open their eyes. C-partial pressure of an anesthetic at which autonomic blockade occurs. D-partial pressure of an anesthetic at which amnesia occurs.
C-partial pressure of an anesthetic at which autonomic blockade occurs MAC-BAR is the minimum alveolar concentration that blocks autonomic reflexes. MAC-BAR is considerably greater than MAC, particularly in the absence of opioids. It has been estimated that MAC-BAR is approximately 50% above standard MAC.
Cholinesterase inhibitors that freely cross the blood-brain barrier include: A-neostigmine B-pyridostigmine C-physostigmine D-edrophonium
C-physostigmine Physostigmine is a teritary amine and has a carbamate group, but no quaternary ammonium. Therefore, it is lipid soluble and is the only clinically available cholinesterase inhibitor that freely passes the blood-brain barrier.
Cholinesterase inhibitors that freely cross the blood-brain barrier include: A-neostigmine B-pyridostigmine C-physostigmine D-edrophonium
C-physostigmine Physostigmine is a teritary amine and has a carbamate group, but no quaternary ammonium. Therefore, it is lipid soluble and is the only clinically available cholinesterase inhibitor that freely passes the blood-brain barrier.
The essential component of cardioplegia solutions is: A-mannitol B-magnesium C-potassium D-corticosteroid
C-potassium High concentrations of potassium (20 - 30 mEq/L) are used in cardioplegia solutions. These solutions result in an increase in extracellular potassium and reduce transmembrane potential. This progressively interferes with the normal sodium currents of depolarization and eventually the sodium channels are completely inactivated.
Sensory innervation of the trachea and larynx below the vocal cords is supplied by the: A- internal laryngeal nerve B- external laryngeal nerve C- recurrent laryngeal nerve D- glossopharyngeal nerve
C-recurrent laryngeal nerve The vagus nerve provides sensation to the airway below the epiglottis. The superior laryngeal branch of the vagus divides into an external (motor) and internal (sensory) laryngeal nerve that provide sensory supply to the larynx between the epiglottis and the vocal cords. Another branch of the vagus, the recurrent laryngeal nerve, innervates the larynx below the vocal cords and trachea.
The effects of barbiturates on ischemic areas of the brain include: A-vasoconstriction B-vasodilation C-redirection of blood flow to the ischemic areas D-redirection of blood flow away from ischemic areas
C-redirection of blood flow to the ischemic areas Barbiturates cause cerebral vasoconstriction in normal areas. These agents tend to redistribute blood flow to ischemic areas in what is sometimes referred to as a reverse steal phenomenon or Robin Hood effect. Ischemic areas remain maximally dilated and unaffected by the barbiturate.
Serotonin has vasodilatory properties in the: (Select 2) A-renal vasculature B-hepatic vasculature C-skeletal muscle vasculature D-pulmonary vasculature E-coronary vasculature
C-skeletal muscle vasculature, E-coronary vasculature Serotonin is a vasoconstrictor in most vascular beds, but has vasodilatory properties in the vasculature of the heart and skeletal muscle.
Which of the following statements regarding fresh-frozen plasma (FFP) is correct? A. Contains all of the clotting factors except factor VIII B. Should not be used in patients with antithrombin III deficiency C. Carries the same infection risk as a unit of whole blood D. Is contraindicated in the case of isolated-factor deficiencies.
C. FFP is the fluid portion obtained from a single unit of whole blood that is frozen within 6 hours of collection. All coagulation factors, except platelets, are present in FFP, which explains the use of this component in the treatment of hemorrhage. FFP is also indicated in antithrombin III deficiency and isolated-factor deficiencies. A transfusion of FFP carries the same risk of infection as transfusing a whole blood.
The incidence of distal ischemia resulting from arterial cannulation is less than A. 10% B. 1% C. 0.1% D. 0.01%
C. Complications from arterial cannulation include distal ischemia (<0.1%), infection, and hemorrhage. Common sites for cannulation include radial, brachial, axillary, dorsalis pedis, and femoral arteries. Common indications for direct blood pressure monitoring include cardiopulmonary bypass, when wide swings in BP are expected, when rigorous control of BP is necessary, and when there is need for multiple arterial blood gas measurements.
During cervical spine surgery for the resection of an intradural mass, the patient begins to cough. The concentration of isoflurane is subsequently increased. With respect to somatosensory-evoked potential (SSEP) monitoring, you would expect: A. Amplitude and latency to decrease B. Amplitude and latency to increase C. Amplitude to decrease and latency to increase D. Amplitude to increase and latency to decrease
C. Halogenated anesthetics as well as nitrous oxide (especially when combined together) can decrease amplitude and increase latency. For this reason, it is recommended to minimize the use of volatile anesthetics to below 1 MAC, or to use a total intravenous technique when monitoring SSEPs.
Major benefits of a neuraxial block in a Whipple procedure include all the following, except A. Decreases the incidence of atelectasis B. Leads to earlier return of GI function C. Decreases the risk of urinary retention D. Reduces the risk of pulmonary embolism or deep-vein thrombosis.
C. Neuraxial blocks in upper abdominal and thoracic procedures offer advantages of decreased pulmonary and cardiac complications in high-risk patient populations, promote peristalsis, and reduce conditions for a hypercoagulation state perioperatively. However, urinary retention is one of the potential major side effects associated with neuraxial blockade.
Approximately 30 minutes after the induction of general anesthesia in a healthy adult patient, you notice that core body temperature has dropped by a full degree Celsius. This is most likely due to: A. Conduction B. Convection C. Redistribution D. Radiation
C. On average, core temperature declines by approximately 1 to 1.5°C after the induction of general anesthesia. This initial drop in core body temperature is primarily due to redistribution (core to periphery) from the vasodilating properties of many anesthetics. Temperature may continue to drop as processes of heat loss, such as conduction, convection, radiation, and evaporation, occur (as opposed to redistribution).
An alcoholic 62-year-old male patient is noted to have jaundice one day after a laparoscopic cholecystectomy under halothane/fentanyl general endotracheal anesthesia. Bilirubin and alkaline phosphatase are elevated, but alanine aminotransferase (serum glutamic-pyruvic transaminase [SGPT]) and aspartate aminotransferase (serum glutamic-oxaloacetic transaminase [SGOT]) are within normal ranges. Of note, all values were within normal limits in this patient preoperatively. The most likely cause of his jaundice is: A. Idiopathic halothane hepatic injury B. Worsening of underlying chronic liver dysfunction C. Posthepatic biliary obstruction D. Intravenous acetaminophen administration
C. Postoperative liver dysfunction is common, but is generally mild and asymptomatic (Table 14-2). Mild transient increases in serum levels of liver enzymes (SGOT/SGPT) are often seen within hours of surgery, but rarely persist >2 days. Subclinical hepatocellular injury can occur in up to 50% of those receiving an inhaled anesthetic with halothane. Though volatile anesthetics are often implicated as the cause of postoperative jaundice, there are many other causes to consider. A surgical cause is likely if the operation involved the liver or biliary tract. Drugs, including antibiotics, and other metabolic or infectious causes must also be ruled out.
An important consideration in using the subclavian approach for central venous access includes the A. Ease of compressibility if a hematoma or laceration develops B. Lower risk of pneumothorax when compared to internal jugular approach C. Ability of the vessel to remain patent in the setting of hypovolemia D. Increased risk of damaging the brachial plexus when compared to internal jugular approach
C. Risks and benefits of different central cannulation sites are important for an anesthesia provider to understand. The internal jugular approach has good landmarks, predictable anatomy, and the convenience of being easily accessible at the head of the bed. Disadvantages include risk of carotid artery puncture, trauma to the brachial plexus, and risk of pneumothorax with lower placements. The left internal jugular vein carries the added risk of damage to the thoracic duct, and can be more difficult to pass a pulmonary artery catheter when needed. The external jugular vein can also be cannulated, and its superficial location makes it an easy target, but it can be more difficult to thread a catheter centrally. The subclavian approach has the benefit of also having good landmarks, as well as remaining relatively patent in a hypovolemic patient. The subclavian however does carry the highest risk of pneumothorax, and can be difficult to compress if a hematoma or laceration occurs.
The probability of developing anti-D antibodies after a single exposure to the Rh antigen is A. <1% B. 5% to 10% C. 50% to 70% D. >80%
C. The Rh blood group is second in importance only to the ABO blood group in the field of transfusion medicine. It has remained of primary importance in obstetrics, being the main cause of hemolytic disease of the newborn. The significance of the Rh blood group is related to the fact that the Rh antigen (D antigen) is highly immunogenic. In the case of the D antigen, individuals who do not produce the D antigen will produce anti-D if they encounter the D antigen when transfused with RBCs (causing a hemolytic transfusion reaction). For this reason, the Rh status is routinely determined in blood donors, transfusion recipients, and mothers-to-be
A leftward shift of the oxyhemoglobin dissociation curve may be related to A. Low levels of 2,3-DPG in packed red blood cells B. Hypothermia resulting from transfusion of blood C. Both A and B D. None of the above
C. The level of 2,3-DPG in stored blood is reduced, causing decreased oxygen unloading to the tissues. Hypothermia also causes a leftward shift of the oxyhemoglobin dissociation curve (Fig. 5-1).
During the course of a complicated cardiac case, the surgeon informs you that he is worried about damage to the right coronary artery in a patient with a right-dominant coronary system. During reperfusion, you are looking for signs of ischemia, and are most interested in leads A. V1-V3 B. V4-V6 C. II, III, and AvF D. I and AvL
C. The understanding of coronary anatomy and regions of ischemia on an ECG is fundamental. The right coronary artery provides perfusion to the inferior of the heart in approximately 80% of patients who are considered to be right-dominant (the posterior descending artery is supplied by the right coronary artery in a rightdominant system). This inferior distribution is represented by leads II, III, and AvF. The anterior wall is supplied by the left anterior descending artery, and is represented roughly by leads V1-V4. The lateral wall of the heart is supplied primarily by the left circumflex artery, and is represented by I, AvL, V5, and V6
Use of lead V5 alone on ECG results in the detection of _____ (%) of ischemic episodes: A. 35 B. 55 C. 75 D. 95
C. The use of the V5 lead results in the detection of 75% of ischemic episodes. This can be increased to 90% with the addition of the V4 lead, and up to 96% with the addition of leads II and V4.
The trauma team in the ICU did not want a thoracic epidural placed on a trauma patient with bilateral rib fractures secondary to concerns about the potential hemodynamic instability that may result. Therefore, both right T7 and left T5 continuous paravertebral catheters were successfully placed for this patient under ultrasound guidance. Twenty minutes following the administration of 10 mL of 0.2% ropivacaine administered through each catheter (following evidence of negative aspiration), the systolic blood pressure dropped by 50 mm Hg. The most likely diagnosis is A. Performance of paravertebral blockade creates identical concerns about potential hemodynamic compromise as do thoracic epidural blocks B. Local anesthetic toxicity as the paravertebral space is very vascular C. Possible epidural spread of local anesthetics from either one or both the paravertebral catheters D. Venous bleeding into the paravertebral space resulting in large volumes of local anesthetic absorption from the paravertebral blocks
C. A potential advantage of paravertebral blockade compared to neuraxial blockade is a reduced incidence of creating an intense sympathectomy resulting in hemodynamic compromise. However, when bilateral paravertebral blocks are performed, the potential exists that epidural spread could be significant, resulting in an observation of a moderate BP decrease.
Anatomical location of the musculocutaneous nerve in the upper forearm is most frequently found within which of the following muscles? A. Triceps brachii B. Biceps brachii C. Coracobrachialis D. Brachialis
C. Although some anatomical variation can be found with the brachial plexus at the level of the axilla, the musculocutaneous nerve is most commonly positioned within the coracobrachialis muscle or between the bellies of the biceps and coracobrachialis muscles.
Which of the following statements would be considered false with regard to extracorporeal shock wave lithotripsy (ESWL)? A. Delivery of the shock wave is timed to coincide with the ventricular refractory phase B. Neuraxial anesthesia up to T2 sensory level is adequate C. If able to control ventilation, use high tidal volumes and low respiratory rate D. Removal of the patient from the bath water can be accompanied by a decrease in the blood pressure
C. An advantage of providing a general anesthetic for ESWL is that ventilatory parameters can be controlled using high frequency and low volumes to decrease stone movement with respiration.
All of the following fluids are generally considered to be isotonic, except A. Lactated Ringer B. Normal saline C. D5 normal saline D. D5¼ normal saline
C. An intravenous solution's effect on fluid movement depends in part on its tonicity. This term is sometimes used interchangeably with osmolarity, although they are subtly different. Osmolarity is the number of osmoles or moles of solute per liter of solution. Tonicity is the effective osmolality and is equal to the sum of the concentrations of the solutes which have the capacity to exert an osmotic force across the membrane. A solution is isotonic if its tonicity falls within (or near) the normal range for blood serum—from 275 to 295 mOsm/kg. A hypotonic solution has lower osmolarity (<250), and a hypertonic solution has higher osmolarity (>350)
Performing an infraclavicular approach for brachial plexus blockade would deposit local anesthetics at which of the following anatomical levels of the plexus? A. Trunks B. Divisions C. Cords D. Roots
C. At the infraclavicular level, the brachial plexus forms three cords in relation to axillary artery and named according to their position around the artery: medial, lateral, and posterior cords.
The most reliable monitor for neurologic monitoring in a patient undergoing carotid endarterectomy is A. Electroencephalogram B. Jugular venous oxygen saturation C. Awake neurologic exam D. Stump pressure
C. Awake neurological status is the most reliable method to detect cerebral ischemia. In patients undergoing carotid endarterectomy under local anesthesia and mild sedation, global and focal neurological status can be continuously assessed. In patients undergoing carotid endarterectomy under general anesthetic indirect methods to detect cerebral ischemia can be used. These include EEG monitoring, transcranial Doppler, arteriography, and measurement of blood flow using xenon.
Which of the following is the most important effect of adding epinephrine to local anesthetics for digit block? A. Prolonged block B. There is no difference C. Compromised blood flow to the digit D. Decrease in local anesthetic vascular update
C. Compromised blood flow to the digit. Addition of a vasoconstrictor can seriously compromise blood flow to the digit and should not be used.
The P50 when the oxyhemoglobin dissociation curve shifts to the left. A. Stays the same. B. Increases C. Decreases.
C. Decreases. A left-shift in the oxyhemoglobin curve indicates that oxygen is less readily released from the oxyhemoglobin complex. The P50 (oxygen tension) at which the hemoglobin complex is 50% saturated. Therefore, as physiological conditions cause the P50 to decrease the oxyhemoglobin curve complex holds the oxygen molecule more tightly.
Which of the following choices is NOT consistent with a limb affected by complex regional pain syndrome? A. Osteoporosis B. Allodynia C. Dermatomal distribution of pain D. Atrophy of the involved extremity E. Hyperesthesia
C. Dermatomal distribution of pain. Complex regional pain syndromes are associated with trauma. The main feature is burning and continuous pain that is exacerbated by normal movement, cutaneous stimulation, or stress usually weeks after the injury. The pain is not anatomically distributed. Other associated features include cool, red, clammy skin and hair loss in the involved extremity. Chronic cases may be associated with atrophy and osteoporosis.
You have just administered a bolus of 2% lidocaine (25 mL) through an epidural catheter that has been working well for labor analgesia in preparation for emergency cesarean section for fetal distress in an otherwise-healthy 35-year-old woman. Shortly after administration of lidocaine, the patient complains of nausea, and you notice that her heart rate has decreased from 99 to 38 bpm. The most likely cause is A. Anaphylactic reaction to lidocaine B. Pneumothorax C. Epidural level is higher than T4 D. Amniotic fluid embolus
C. Epidural level is higher than T4. A large local anesthetic bolus to a parturient with an anticipated epidural space reduced in size secondary to engorged epidural veins and enlarged uterus can cause a higher level of epidural blockade than anticipated. If the block level reaches higher than T4 and influences T1-T4 (cardiac accelerator fibers), patients may have bradycardia, hypotension, anxiety on physical exam and report symptoms such as nausea, vomiting, and headache, and even paresthesia in the upper extremities
The sacral canal is the sacral continuation of which spinal structure. A. Subarachnoid space. B. Subdural space. C. Epidural space. D. Intraspinous space.
C. Epidural space.
Which of the following clotting factors has the shortest half-life? A. Factor II B. Factor V C. Factor VII D. Factor IX E. Factor X
C. Factor VII Factor Vll is one of the four vitamin-K-dependent clotting factors (factors II, Vll, IX, and X). It also has the shortest half-life of all the clotting factors (4 to 6 hours) and is the first factor to become deficient in patients with severe hepatic failure, Coumadin anticoagulation therapy, and vitamin K deficiency. The PT is most sensitive to decreases in factor Vll
The most common cause of an acute hemolytic transfusion reaction is A. An error during type and screen B. An error during type and crossmatch C. Misidentification of the patient, blood specimen, or transfusion unit D. Defective blood filter
C. Hemolytic reactions occur when the wrong blood type is administered to a patient. The immediate signs of acute hemolytic transfusion reactions include lumbar and substernal pain, fever, chills, dyspnea, flushing of the skin, and hypotension. The appearance of free hemoglobin in plasma or urine is presumptive evidence of a hemolytic reaction. Acute renal failure reflects precipitation of stromal and lipid contents (not free hemoglobin) of hemolyzed erythrocytes in distal renal tubules. Acute hemolytic transfusion reactions are usually due to ABO blood incompatibility, and the most common cause is misidentification of the patient, blood specimen, or transfusion unit (clerical error).
All of the following solutions contain potassium, except A. Lactated Ringer solution B. PlasmaLyte C. Hespan D. Packed red blood cells
C. Hespan is colloid containing starch and saline. All of the other options contain potassium. Many patients with hyperkalemia, including patients with renal failure, routinely receive normal saline because it contains no potassium
The following fluid should be avoided in a patient undergoing craniotomy A. Lactated Ringerés B. Normal saline C. Dextrose 5%—normal saline D. Hetastarch
C. In a patient undergoing craniotomy, intravenous fluid replacement should be performed by using glucose-free isotonic crystalloid or colloid solutions. Hyperglycemia is known to worsen ischemic brain injury.
An 85-year-old male is scheduled for a right distal radius and ulnar open reduction interior fixation at the wrist. Medical history is significant for chronic obstructive pulmonary disease dependent on 2 L of oxygen, hypertension, diabetes mellitus, and coronary artery disease with a stent inserted one year ago. Given that the surgeon plans to use a forearm tourniquet, the regional anesthesia technique that would be most appropriate for this patient is A. An interscalene brachial plexus block plus an intercostal brachial nerve block B. A supraclavicular approach to the brachial plexus plus an intercostal brachial nerve block C. An infraclavicular block of the brachial plexus at the cords plus an intercostal brachial nerve block D. Superficial cervical plexus blockade plus an intercostal brachial nerve block
C. In a patient with severe pulmonary compromise, performing either an interscalene or supraclavicular block of the brachial plexus should be approached with caution secondary to the increased risk of an ipsilateral phrenic nerve palsy. Placement of an interscalene block for wrist surgery may also not be optimal as it may not effectively block the ulnar nerve distribution to the wrist. A superficial cervical plexus block (C1-C4) will not effectively provide anesthesia/analgesia to the wrist. Both infraclavicular and axillary approaches to the brachial plexus would be appropriate for wrist surgery, along with a reduced incidence of adverse effects on the phrenic nerve. Intercostobrachial nerve blockade is added to cover the T2 dermatome distribution that is not included in a properly performed brachial plexus block and will contribute to alleviating tourniquet discomfort in the medial portion of the upper arm.
You are caring for an 18-year-old female trauma patient who was emergently transported to the operating room for control of massive bleeding. Due to the acuteness of the patient's bleeding, there was no time for blood typing and she has received 3 units of O-negative packed red blood cells. The blood bank notifies you that the patient's blood type is A-positive. If the patient requires further transfusion, which of the following should be administered? A. A-positive RBCs B. A-negative RBCs C. O-negative RBCs D. RhoGAM
C. In an emergency situation that requires transfusion before type and compatibility testing can be performed, O-negative packed red blood cells may be administered. Even if the patient's blood type becomes known and available, after 2 units of type O-negative packed red blood cells have been transfused, subsequent transfusions should continue with O-negative blood. RhoGAM is not indicated since the patient's blood type is Rh+.
Normal systemic vascular resistance ranges between ______ (dynes)(s)/cm5: A. 50 and 150 B. 300 and 600 C. 900 and 1500 D. 1800 and 2100
C. Interpreting physiologic data from a pulmonary artery catheter and guiding therapy requires having an intimate knowledge of baseline values. On average, normal physiologic vascular resistance falls between 900 and 1500 (dynes)(s)/cm5
The primary determinant of local anesthetic potency is A. pKa B. Molecular weight C. Lipid solubility D. Concentration E. Protein binding
C. Lipid solubility Potency of local anesthetics is directly related to its lipid solubility. Speed of onset is related to the pKa. The degree of protein binding is important for toxicity and metabolism.
The primary determinant of local anesthetic potency is A. pKa B. Molecular weight C. Lipid solubility D. Concentration E. Protein binding
C. Lipid solubility. Potency of local anesthetics is directly related to its lipid solubility. Speed of onset is related to the pKa. The degree of protein binding is important for toxicity and metabolism
All of the following patients should have a cardiology consult prior to non-cardiac surgery except: A. Unstable angina B. Atrial fibrillation with ventricular rate of 105 C. Mild tricuspid regurgitation D. New-onset heart failure
C. Mild tricuspid regurgitation
18. Which of the following statements regarding transfusion of packed red blood cells is most correct? A. The hematocrit of 1 unit is usually 30% to 40% B. Transfusion of a single unit will increase an adult's hemoglobin concentration about 4 g/dL C. May cause clotting if the transfused packed red blood cells are mixed with lactated Ringer solution D. Their principle use as that of a volume expander.
C. Mixing of packed red blood cells with lactated Ringer solution can cause clotting as the citrate in the blood product can bind with calcium in the lactated Ringer. The other options are all false. The hematocrit of 1 unit of packed red blood cells is 70% to 80%. Transfusion of a single unit will increase an adult's hemoglobin concentration by about 1 g/dL. The objective in transfusion of packed red blood cells is to increase the blood's oxygen-carrying capacity. Although transfusion of packed red blood cells increases intravascular fluid volume, they should not be used routinely for this purpose given the risks associated with transfusion.
After performing an axillary peripheral nerve block, your ultrasound probe moves to scan laterally and you see what appears to be an oval and hyperechoic nerve structure within the belly of the coracobrachialis muscle. When the needle tip is advanced closer to this structure and the nerve stimulator is activated, you notice that the elbow begins to flex. The most likely nerve branch that is being stimulated is A. Median nerve B. Triceps brachii nerve C. Musculocutaneous nerve D. Radial nerve
C. Musculocutaneous nerve is frequently found within coracobrachialis muscle and/or between the biceps and coracobrachialis muscles. Stimulation of the musculocutaneous nerve will characteristically cause elbow flexion.
The cardiac index in a healthy adult ranges between ______ L/min/m2: A. 0.8 and 1.2 B. 1.4 and 2.0 C. 2.2 and 4.2 D. 4.4 and 6.0
C. Normal cardiac index in a healthy adult ranges between 2.2 and 4.2 L/min/m2. Cardiac index is often used over cardiac output in estimating cardiac function, since it is more reliable with extremes of height
Bacterial infection due to a contaminated blood product is most likely with transfusion of: A. Packed red blood cells B. Fresh-frozen plasma C. Platelets D. Cryoprecipitate
C. One of the leading causes of transfusion-related fatalities in the United States is bacterial contamination, which is most likely to occur in platelet concentrates. Platelet-related sepsis can be fatal and occurs as frequently as 1 in 5,000 transfusions. Platelets are stored at 20 to 24°C instead of 4°C, which probably accounts for the greater risk of bacterial growth than with other blood products. Any patient in whom a fever develops within 6 hours of receiving platelet concentrates should be considered to be possibly manifesting platelet-induced sepsis, and empirical antibiotic therapy should be instituted.
A 65-year-old female is scheduled for a right total shoulder replacement. Under ultrasound guidance, you perform a right interscalene nerve block and place a catheter for continuous local anesthetic infiltration planned for 3 days. One week later, the patient complains of persistent parasthesia of the entire right arm, including the wrist, hand, and all fingers (from the shoulder to the fingers). An MRI shows a diffuse swelling of the brachial plexus at the level of the cords. The most likely diagnosis is:: A. Direct nerve injury/trauma from the block needle used B. Irritation of the brachial plexus at the level of the branches from the continuous peripheral nerve catheter C. Surgical trauma/manipulation of the brachial plexus at the level of the cords D. Local anesthetic toxicity of the brachial plexus at the level of the roots/trunks
C. Shoulder surgery is one of the upper extremity procedures that can often be associated with nerve injuries secondary to patient pathology, surgical manipulation(s), surgical trauma, brachial plexus nerve stretching or compression, etc. If such an injury was due to performance of the peripheral nerve block and/or catheter placement, it often tends to involve more isolated nerve roots/trunks of the brachial plexus from the interscalene approach rather than diffuse influences at more distal levels of the plexus. Surgical complications of the brachial plexus often tend to be more diffuse and less selective. Nerve-conduction studies and EMG should be considered rather than merely delineating an etiology of the injury.
A pulmonary artery catheter is placed to help guide management of an obese patient with a known history of poorly controlled obstructive sleep apnea who is admitted with refractory hypotension. Cardiac output and pulmonary artery occlusion pressures are markedly decreased, while central venous and pulmonary artery pressures are markedly increased. Of the options listed below, the most beneficial intervention at this time would be to A. Administer volume B. Begin diuresis C. Start an infusion of milrinone D. Start an infusion of epinephrine
C. Start an infusion of milrinone The patient's history and clinical scenario suggest right heart failure due to pulmonary hypertension. Milrinone may be beneficial in decreasing pulmonary vascular resistance as well as increasing cardiac output.
A spinal neuraxial anesthetic was given 20 minutes earlier to a 28-year-old G3P2 parturient scheduled for repeat cesarean section. Alcohol swab exam revealed that she has lost temperature sensation up to T2 level. At what level do you anticipate the block will reach to provide adequate pain control? A. T2 B. T3 C. T4 D. T5
C. T4 In spinal and epidural anesthesia, differential blockade is frequently reported to observe the "two segments rule," namely, sympathetic block is two segments higher than sensory block, and sensory block is two segments higher than motor block. In this spinal block, alcohol swab tested the level of sensory/sympathetic blockade
The artery of Adamkiewicz most frequently arises from the aorta at which spinal level? A. TI-T4 B. T5-T8 C. T9-T12 D. LI-L4 E. L5-S3
C. T9-T12 The artery of Adamkiewicz is also called the arteria radicularis magna and is one of the "feeder" arteries for the anterior spinal artery. Damage to this artery can lead to ischemia in the thoracolumbar region of the spinal cord. The origin of this artery is variable as follows: T9-T12 in 60% of cases; T5-T8 in 14% of cases; and below Ll in 20% of cases.
True statement regarding cerebral physiology is: A. Normal cerebral metabolic oxygen consumption is 5 mL/100g/min B. Normal Intracranial pressure (ICP) is approximately 15 mm Hg C. Normal cerebral blood flow (CBF) is 50 mL/100g/min D. Cerebral autoregulation is strictly maintained at blood pressures between 60 and 150 mm Hg in all patients
C. The cerebral metabolic rate is reflected by oxygen consumption, which is about 3 to 3.8 mL/100 g/min. Total CBF averages 50 mL/100 g/min. In normal individuals, CBF remains nearly constant between mean arterial pressures of about 60 and 160 mm Hg. The cerebral autoregulation curve is shifted to right in patients with chronic arterial hypertension. ICP by convention means supratentorial CSF pressure measured in the lateral ventricles or over the cerebral cortex, and the normal CSF pressure is 10 mm Hg or less.
The most appropriate statement regarding the function of the saphenous nerve is: A. It serves as both a motor nerve and a sensory nerve B. It is the motor terminal branch of the femoral nerve C. It is the sensory terminal branch of the femoral nerve D. It is a sensory terminal branch of the sciatic nerve
C. The saphenous nerve is a terminal sensory nerve branch of the femoral nerve with NO motor components. Under certain clinical situations, the saphenous nerve is preferentially blocked to avoid motor blockade of the anterior quad muscles that can result from performance of a femoral nerve block (increased risk of fall
The tip of a pulmonary artery catheter typically enters the pulmonary artery at approximately A. 15 to 25 cm B. 25 to 35 cm C. 35 to 45 cm D. 45 to 55 cm
C. The tip of the pulmonary artery catheter typically enters the pulmonary artery at around 35 to 45 cm. This can vary from patient to patient, especially with patients at the extremes of height.
Which of the following types of neuro-monitoring can be done in a patient undergoing transsphenoidal resection of a pituitary tumor? A. EEG B. Motor-evoked potentials C. Visual-evoked potentials D. Auditory-evoked potentials
C. The transsphenoidal or bifrontal craniotomy approach may be used to gain access to pituitary gland. The former (transsphenoidal approach) has several advantages including elimination of frontal lobe retraction, microsurgical removal of small adenomas, reduced blood loss, and shorter hospital stay. Patients are intubated endotracheally (oral), and oropharyngeal packing is done to prevent bleeding into the esophagus. Additionally, epinephrine or cocaine may be injected submucosally to reduce bleeding. The cavernous sinus forms the lateral border of the sella turcica and includes the internal carotid artery, venous structures, and cranial nerves III, IV, V, and VI. Therefore, visual-evoked potentials may be monitored in the OR for early detection of visual pathway damage.
A patient is undergoing craniotomy for subdural hematoma. During the procedure, the surgeon requests lowering the intracranial pressure. All the following can be used, except A. Mannitol B. Hyperventilation C. Steroids D. Furosemide
C. Treatment of intracranial hypertension includes hyperventilation to PaCÓ of 25 to 30 mm Hg, improving CSF drainage by elevating the head by 30 degrees or surgical placement of CSF drain, using an osmotic diuretic (mannitol), hypertonic saline, decompression craniectomy, barbiturates, and corticosteroids. The latter have been used to decrease cerebral edema, and take a few hours to have effect, but routine use of corticosteroids in managing intracranial hypertension is not recommended.
he body mass index (BMI) associated with morbid obesity is: A- > 30 B-> 35 C-> 40 D-> 45
C> 40 Overweight and obesity are classified using the BMI. Overweight is defined as a BMI > 24, obesity as a BMI > 30, morbid obesity as a BMI > 40, super obesity as a BMI > 50 and super-super obesity as a BMI > 60. BMI is calculated with the following formula: BMI = Weight (kg) / Height (meters)2
Match each local anesthetic with its pKa. a. Chloroprocaine ,,,,,,,,,,,,,,,,,,,,,,,1. 7.6 b. Ropivacaine k,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,2. 7.9 c. Lidocaine ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,3. 8.7 d. Mepivacaine,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, 4. 8.1
Chloroprocaine= 8.7 Ropivacaine= 8.1 Lidocaine= 7.9 Mepivacaine= 7.6
A patient experiences low vision following a lumbar laminectomy in the prone position. What is the etiology? (A) Decreased intracranial pressure (B) Decreased venous pressure (C) Increased cerebral blood low (D) Decreased ocular perfusion pressure
D) Decreased ocular perfusion pressure Physiological changes in the prone position include increased intracranial pressure; increased venous pressure and decreased cerebral blood ow. Postoperative vision loss is due to increased ocular venous pressure as well as decreased ocular perfusion pressure.
Each of the following statements concerning rotameters is true EXCEPT A. Rotation of the bobbin within the Thorpe tube is important for accurate function B. The Thorpe tube increases in diameter from bottom to top C. Its accuracy is affected by changes in temperature and atmospheric pressure D. The rotameter for N20 and CÓ are interchangeable E. The rotameter for Ó should be the last in the series
D) Rotameters consist of a vertically positioned tapered tube that is smallest in diameter at the bottom (Thorpe tube). Gas enters at the bottom of the Thorpe tube and elevates a bobbin or float, which comes to rest when gravity on the float is balanced by the fall in pressure across the float. The rate of gas flow through the tube depends on the pressure drop along the length of the tube, the resistance to gas flow through the tube, and the physical properties (density and viscosity) of the gas. Because few gases have the same density and viscosity, rotameters cannot be used interchangeably.
During a general anesthetic you suspect an episode o malignant hyperthermia (MH). What will you do first? (A) Call the MHAUS hotline. (B) Administer dantrolene. (C) Inform the surgeon. (D) Turn of inhalational agents
D) Turn of inhalational agents When suspicion of an episode of malignant hyperthermia exists, each of the responses is in order; however, turning of the inhalational agents is the first priority.
Which of the following is correct about using DDAVP perioperatively? A . DDAVP reduces blood transfusions in patients without bleeding disorders. B. DDAVP treats nephrogenic diabetes insipidus. C . DDAVP treats factor deficiency in hemophilia B. D. DDAVP is useful to reduce bleeding in uremic patients. E. DDAVP can be used in all patients with von Willebrand disease.
D). DDAVP is useful to reduce bleeding in uremic patients. Desmopressin, or DDAVP , is an analog of antidiuretic hormone (ADH). When administered, it stimulates the release of stored von Willebrand factor and factor VIII from the vascular endothelium within 30 to 60 minutes for a continued effect of up to 24 hours. It is indicated for the treatment of central diabetes insipidus, control of bleeding in mild hemophilia A where the factor VIII activity is more than 5%, and certain subtypes of von Willebrand disease. Its use as a treatment for uremic patients in acute or chronic renal failure has been shown to reduce bleeding. It is given as a one-time dose of 0.3 mcg/kg, as repeated doses can cause tachyphylaxis. In addition to DDAVP, erythropoietin, cryoprecipitate, and estrogen have also been shown to help treat uremic bleeding. DDAVP has not been shown to reduce the need for blood transfusions in patients without bleeding disorders. DDAVP has no effect on increasing levels of factor IX, the defi cient factor in hemophilia B. Use of DDAVP in von Willebrand disease has a variable response. While it is helpful in increasing levels when there is a mild quantitative defi ciency of vWF, such as the most common type I subtype, it can be detrimental and cause severe thrombocytopenia in patients with subtype IIB. N ephrogenic diabetes insipidus has partial to complete resistance to ADH, and thus exogenous administration may not be helpful. Dietary changes, thiazide, and potassiumsparing diuretics and a trial of nonsteroidal anti-infl ammatories are the fi rst line of treatment in nephrogenic diabetes insipidus.
Sickle hemoglobin: (Select 2) A-has a lower P50 than hemoglobin A. B-releases oxygen less readily than hemoglobin A. C-is present in about 30% of African Americans. D-readily polymerizes and precipitates in the red cell. E-results from a single amino acid substitution on the α-chain. F-has decreased solubility as compared to hemoglobin A
D, F Readily polymerizes and precipitates in the red cell, has decreased solubility as compared to hemoglobin A. Sickle hemoglobin (HbS) has a lower affinity for oxygen and an elevated P50 (31 mm Hg) as compared to hemoglobin A (27 mm Hg). HbS also has decreased solubility and readily polymerizes and precipitates in the red cell producing the sickled appearance of the cell. HbS results from the substitution of valine for glutamic acid on the β-chain.
A 34-year-old female is undergoing tumescent liposuction of the abdomen and flanks. Peak serum levels of local anesthetic from the tumescent solution are most commonly seen in: A- the first 2 hours B- 4 to 6 hours C-7 to 9 hours D- 12 to 14 hours
D- 12 - 14 hours Tumescent liposuction is commonly done with large volumes of tumescent solution consisting of normal saline with 1:1,000,000 epinephrine and 0.025 - 0.1% lidocaine. Peak serum levels of lidocaine occur 12 - 14 hours after injection and decline over the next 6 - 14 hours.
During emergent transtracheal jet ventilation using a 14 gauge catheter, generation of sufficient gas flow requires a driving pressure of: A- 20 cmH2O B- 50 cmH2O C- 25 psi D- 50 psi
D- 50 psi After proper location of the catheter is confirmed by aspiration air, jet ventilation may be achieved with intermittent pulses of oxygen at 50 psi.
Which of the following is a source of airway obstruction when the tensor palatine muscle is relaxed? A- tongue B- Hard palate C- Epiglottis D- Soft palate
D- Soft palate. Tensor palate relaxation effects = soft palate. Genioglottus relaxation effects - tongue Hyoid muscle relaxtion effects = epiglottis
The rapid shallow breathing index (RSBI) is useful in predicting successful weaning from mechanical ventilation. Prior to extubation this index should be: A- between 300 and 400 B- between 200 and 300 C- between 100 and 200 D- less than 100
D- less than 100 RSBI is frequently used to help predict who can be successfully weaned from mechanical ventilation. With the patient breathing spontaneously, the ventilatory rate is divided by the tidal volume (liters). Successful extubation can be predicted by an RSBI of less than 100.
During emergent transtracheal jet ventilation using a 14 gauge catheter, generation of sufficient gas flow requires a driving pressure of: A-20 cmH2O B-50 cmH2O C-25 psi D-50 psi
D-50 psi After proper location of the catheter is confirmed by aspiration air, jet ventilation may be achieved with intermittent pulses of oxygen at 50 psi.
A 62-year-old otherwise healthy woman loses 1000 mL of blood rapidly during a partial hepatectomy. After adequate volume resuscitation, including the initiation of packed red blood cell transfusion, she becomes increasingly hypotensive and tachycardic. Her vital signs are BP 64/42 mmHg, HR 136 bpm, SpO2 98%, temperature 38.4°C. What is the MOST appropriate next step in management? A-Continue packed red blood cell transfusion B-Initiate fresh frozen plasma transfusion C-Continue volume resuscitation with tetrastarch D-Discontinue transfusion
D-Discontinue transfusion This patient has signs suggestive of an acute transfusion reaction. Despite adequate volume resuscitation and control of surgical bleeding, she is hypotensive, tachycardic and febrile after the initiation of packed red blood cell transfusion. The transfusion should be discontinued and the blood sent back to the blood bank for testing. Febrile transfusion reactions occur in 0.5% of RBC transfusions and 30% of platelet transfusions and are thought to be due to recipient antibodies directed against HLA antigens on donor WBC or platelets. Cytokines released from WBC in stored blood product (especially platelets) may also be a contributing factor. Patients experiencing a febrile reaction have increase in temperature of > 1 C as well as headache and back pain (not obvious in patient under general anesthesia) in addition to signs similar to allergic reaction. The febrile reaction is usually delayed up to 2 hours after the transfusion but is treated successfully with acetaminophen and diphenhydramine. Leukoreduction helps to reduce febrile transfusion reactions. An acute hemolytic transfusion reaction is usually the result of ABO blood group incompatibility and may be fatal. Patients having acute hemolytic reaction present with fever, dyspnea, chest pain, low back pain and sudden hypotension. Under general anesthesia only hypotension and fever may be apparent. Acute renal failure may result; the transfusion should be stopped and volume resuscitation with addition of mannitol or furosemide should be considered.
Systemic levels of mepivacaine would MOST likely be the greatest 10 minutes after which of the following regional techniques using an equal volume of 1.5% mepivacaine? A-Brachial plexus B-Caudal C-Epidural D-Intercostal
D-Intercostal Systemic absorption of a local anesthetic is determined by the site of injection, the concentration and volume of local anesthetic, the addition of vasoconstricting additives, and the pharmacologic profile of local anesthetic. Generally speaking, the more vascular the region the higher the blood levels after injection. Absorption from the intercostal space is rapid, with plasma concentrations peaking as quickly. Many people use the acronym "ICE-BS" (Intercostal -- Caudal -- Epidural - Brachial plexus - Spinal) to remember fastest to slowest systemic absorption.
A 24-year-old man with a history of T4 paraplegia is undergoing his first anesthetic for a urinary diversion due to a neurogenic bladder. As the surgeon makes the incision, his BP reaches 220/110 mmHg with a heart rate of 45 bpm. Which of the following is the MOST appropriate first step in treatment? A-Atropine B-Dantrolene C-Fentanyl D-Nitroprusside
D-Nitroprusside In a patient with a history of a spinal cord lesion higher than T7, marked hypertension and bradycardia is concerning for autonomic hyperreflexia. Normally, descending inhibitory impulses travel down the spinal cord to block reflex arcs to cutaneous, visceral, or proprioceptive stimuli. This arc is disrupted in spinal cord injury and can lead to autonomic instability, most notably severe hypertension followed by a sustained vagal response including bradycardia, vasodilation, and cutaneous flushing. Treatment is supportive, including stopping the inciting stimulus (ask surgeons to pause) and lowering the blood pressure to normal levels via vasodilators and assuring adequate levels of anesthesia.
Which of the following conditions is MOST associated with excessive neck flexion in the seated position? A-Central retinal artery occlusion (CRAO) B-Decreased airway pressure C-Decreased intracranial pressure D-Quadriplegia
D-Quadriplegia The seated position, although providing optimal surgical conditions in certain cases, places the patient at some specific risks associated with the position itself. Specifically, neck flexion in the seated position poses certain risks. Quadriplegia has been reported and is thought to be due to compression of the cervical spinal cord in combination with lowered perfusion pressure. Patients who have pre-existing spinal stenosis are predisposed to this complication. Increased airway pressure can occur as a result of occlusion of an endotracheal tube from neck flexion. While the seated position may be associated with decreased intracranial pressure (ICP), neck flexion in the seated position may cause increased ICP due to occlusion of venous drainage via compression of the internal jugular veins. Central retinal artery occlusion is most commonly associated with prone positioning and increased pressure on the ocular globe.
Which of the following conditions is MOST associated with excessive neck flexion in the seated position? A=Central retinal artery occlusion (CRAO) B-Decreased airway pressure C-Decreased intracranial pressure D-Quadriplegia
D-Quadriplegia The seated position, although providing optimal surgical conditions in certain cases, places the patient at some specific risks associated with the position itself. Specifically, neck flexion in the seated position poses certain risks. Quadriplegia has been reported and is thought to be due to compression of the cervical spinal cord in combination with lowered perfusion pressure. Patients who have pre-existing spinal stenosis are predisposed to this complication. Increased airway pressure can occur as a result of occlusion of an endotracheal tube from neck flexion. While the seated position may be associated with decreased intracranial pressure (ICP), neck flexion in the seated position may cause increased ICP due to occlusion of venous drainage via compression of the internal jugular veins. Central retinal artery occlusion is most commonly associated with prone positioning and increased pressure on the ocular globe.
A 70 kg adult man presents for emergent exploratory laparotomy after free air is seen on abdominal imaging. In addition, his serum sodium is 160 mEq/L. Which of the following is NOT true? A-A relatively higher concentration of sevoflurane will be needed for adequate anesthesia. B-The fastest rate at which his sodium should be corrected is 1.5 mEq/L/h. C-His condition would likely be worsened by administration of demeclocycline. D-Rapid correction of his sodium level could result in permanent neurologic deficit
D-Rapid correction of his sodium level could result in permanent neurologic deficit. In general, plasma sodium concentration should not be decreased faster than 0.5 mEq/L/h. Rapid correction of hypernatremia can result in permanent neurologic damage, as well as seizures and brain edema. Hypernatremia increases the minimum alveolar concentration for inhaled anesthetics. Demeclocycline is a tetracycline antibiotic that interferes with the action of ADH. By blocking ADH at its receptor, demeclocycline impairs the ability of the kidneys to concentrate urine, and therefore may worsen hypernatremia. Because of this effect, demeclocycline is used as off label treatment for SIADH. Hypernatremia increases the MAC of volatile anesthetics.
A 67-year-old, 96-kg man underwent ultrasound-guided supraclavicular blockade for a 2-hour right wrist surgery. Forty ml of 0.5% bupivacaine was injected under ultrasound guidance. In the recovery room the patient reports that his breathing does not feel "normal" and you notice that his pupil diameter is unequal with the right pupil being smaller. Vital signs include HR 65 bpm, BP 117/68 mmHg, SpÓ 98% on room air. Which of the following is the BEST course of action? A-Initiate an intralipid infusion B-Obtain an upright Chest X-Ray C=Perform an emergent needle decompression of the right lung D-Reassure the patient
D-Reassure the patient Although pneumothorax is possible during ultrasound supraclavicular blockade, it is a very rare occurrence. With traditional landmark based supraclavicular block, it is estimated that pneumothorax occurred in 0.5% to 5%. The most common side effects during supraclavicular block are Horner's syndrome (ipsilateral eye ptosis, miosis and anhidrosis) and phrenic nerve blockade. These occur less frequently compared to an interscalene nerve block and are estimated to occur in 30% to 50% of supraclavicular blocks and are more likely when local anesthetic volumes >20 cc are used. Reassure the patient that the symptoms will resolve as the block resolves. This is clearly not local anesthetic toxicity and therefore intralipid infusion would not be helpful.
A 67-year-old, 96-kg man underwent ultrasound-guided supraclavicular blockade for a 2-hour right wrist surgery. Forty ml of 0.5% bupivacaine was injected under ultrasound guidance. In the recovery room the patient reports that his breathing does not feel "normal" and you notice that his pupil diameter is unequal with the right pupil being smaller. Vital signs include HR 65 bpm, BP 117/68 mmHg, SpÓ 98% on room air. Which of the following is the BEST course of action? A-Initiate an intralipid infusion B-Obtain an upright Chest X-Ray C-Perform an emergent needle decompression of the right lung. D-Reassure the patient.
D-Reassure the patient. Although pneumothorax is possible during ultrasound supraclavicular blockade, it is a very rare occurrence. With traditional landmark based supraclavicular block, it is estimated that pneumothorax occurred in 0.5% to 5%. The most common side effects during supraclavicular block are Horner's syndrome (ipsilateral eye ptosis, miosis and anhidrosis) and phrenic nerve blockade. These occur less frequently compared to an interscalene nerve block and are estimated to occur in 30% to 50% of supraclavicular blocks and are more likely when local anesthetic volumes >20 cc are used. Reassure the patient that the symptoms will resolve as the block resolves. This is clearly not local anesthetic toxicity and therefore intralipid infusion would not be helpful.
According to the American College of Cardiology/American Heart Association 2009 Expert Consensus Document on pulmonary hypertension, the diagnosis of pulmonary arterial hypertension does NOT require which of the following? A-Resting mPAP > 25mmHg B-PVR > 3 Wood units C-PCWP/LAP less than or equal to 15mmHg D-Right ventricular hypertrophy
D-Right ventricular hypertrophy. In order to make the diagnosis of pulmonary hypertension, the ACC/AHA expert consensus document requires right heart catheterization and confirmation of all 3 of the following hemodynamic findings: 1) Resting mPAP >25mmHg; 2) PCWP/LAP < 15 mmHg; and 3) PVR > 3 Woods units. Right ventricular hypertrophy is not required.
A 3-month-old full term boy presents for right inguinal hernia repair. He experiences an intravascular injection during the administration of a caudal the test dose. Atropine was administered 5 minutes prior to the test dose. What is the EARLIEST clinical marker of this intravascular injection of epinephrine? A-HR increase greater than 10 bpm B-HR increase greater than 20 bpm C-SBP increase greater than 25 mmHg D-ST segment elevation greater than 25%
D-ST segment elevation greater than 25% The earliest sign of intravascular injection is T wave elevation greater than 25% (not ST segment elevation). Another very sensitive marker of intravascular injection is an elevation in HR of 10 or more bpm. Unlike adults, children are usually under anesthesia during the test dose and the sensitivity of epinephrine is reduced (especially when halothane was used) if the standard HR response of 20 bpm is expected. The administration of an anticholinergic and reducing the HR response to 10 bpm will increase the sensitivity of the test dose. In fact some evidence suggests that if atropine or glycopyrrolate is given prior to the test dose and a HR of 10 bpm is utilized, the sensitivity of 0.5 mcg/kg is 100%.
A 67-year-old man with a history of coronary artery disease, diabetes and hypertension is undergoing coronary artery bypass grafting. After the induction of anesthesia, the patient becomes hypotensive with a blood pressure of 85/47 mmHg. Which of the following monitors is the MOST sensitive for detecting myocardial ischemia? A-Central venous pressure B-Electrocardiogram C-Pulmonary artery occlusion pressure D-Transesophageal echocardiography
D-Transesophageal echocardiography Transesophageal echocardiography (TEE) is an effective tool in detecting myocardial ischemia as manifested by left ventricular systolic dysfunction. In fact, echocardiographic evidence of wall motion abnormalities has been shown to precede ECG evidence of ischemia. Furthermore, TEE has also been shown to be sensitive in the detection of ischemia. Central venous pressure and systolic pulmonary artery pressure may change during ischemia, but neither is sensitive nor specific for ischemia.
Which of the following is LEAST likely to occur following a celiac plexus block? A-Diarrhea B-Orthostatic hypotension C-Retroperitoneal hemorrhage D-Urinary incontinence
D-Urinary incontinence The celiac plexus contains preganglionic sympathetic fibers from greater and lesser splanchnic nerves and postganglionic sympathetic and preganglionic parasympathetic fibers. It provides sensory innervation and sympathetic outflow to the stomach, liver, spleen, pancreas, kidney, and GI tract up to splenic flexure. Thus, blockade of the celiac plexus results in a loss of sympathetic innervation. The loss of sympathetic outflow can result in both diarrhea and orthostatic hypotension. During performance of the block, inadvertent puncture of the aorta or vena cava can result in a retroperitoneal hemorrhage; however, this is less common. Urinary incontinence does not occur and the urinary tract is not innervated by the celiac plexus.
An otherwise healthy 45-year-old woman with IgA deficiency undergoes a multi-level spinal fusion operation in which anticipated blood loss is > 2L. Which of the following is a necessary precaution prior to transfusion of red blood cells? A-Irradiation B-Leukocyte reduction C-Steroid pre-medication D-Washing product
D-Washing product Anti-IgA antibodies may develop in patients who lack IgA, and the administration of blood products (whole blood, PRBCs, platelets, FFP, cryoprecipitate, granulocytes, and IVIG) containing IgA can cause anaphylaxis. Because of this, red blood cells should be washed with normal saline prior to administration to remove as much of the contaminating IgA as possible. If there are no other complicating clinical factors, irradiation, leukocyte reduction and steroid premedication are not indicated (although most blood products in the USA are leukocyte reduced).
An otherwise healthy 45-year-old woman with IgA deficiency undergoes a multi-level spinal fusion operation in which anticipated blood loss is > 2L. Which of the following is a necessary precaution prior to transfusion of red blood cells? A-Irradiation B-Leukocyte reduction C-Steroid premedication D-Washing product
D-Washing product Anti-IgA antibodies may develop in patients who lack IgA, and the administration of blood products (whole blood, PRBCs, platelets, FFP, cryoprecipitate, granulocytes, and IVIG) containing IgA can cause anaphylaxis. Because of this, red blood cells should be washed with normal saline prior to administration to remove as much of the contaminating IgA as possible. If there are no other complicating clinical factors, irradiation, leukocyte reduction and steroid premedication are not indicated (although most blood products in the USA are leukocyte reduced).
In patients with a history of hypertrophic cardiomyopathy, intraoperative management should include: A-a nitroglycerine infusion B-inotropic support C-afterload reduction D-maintenance of adequate preload
D-maintenance of adequate preload In patients with outflow obstruction, myocardial depression and maintenance of preload and afterload are desirable.
The line isolation monitor: A-provides a source of ungrounded electrical power B-reduces the risk microshock C-monitors the integrity of the isolated power system D-monitors the integrity of equipment grounding wires
D-monitors the integrity of the isolated power system The line isolation monitor continuously monitors the integrity of the isolated power system. The line isolation transformer provides ground isolation. Microshock hazards occur with the delivery of 100 microamps or less of current directly to the endocardium. These small amounts of current are well below the sensing range of the ground isolation monitor. The LIM is unable to detect a faulty grounding connection in the equipment attached to the circuit.
Reduction of heart rate seen with the administration of opiates is mediated through the: A- sigma receptors B- delta receptors C-kappa receptors D- mu receptors
D-mu receptors The cardiovascular effects of narcotics appear to be mediated through the mu receptors. In addition, these receptors seem, at least in part, to be responsible for the ventilatory depression associated with narcotic admnistration.
The dibucaine number: A- is normally less than 60%. B-is a quantitative assessment of pseudocholinesterase activity. C-is inversely proportional to pseudocholinesterase function. D-reflects inhibition of pseudocholinesterase by dibucaine.
D-reflects inhibition of pseudocholinesterase by dibucaine.. Dibucaine, a local anesthetic, inhibits normal pseudocholinesterase. Homozygous patients with abnormal pseudocholinesterase characteristically have a dibucaine number of about 20%, heterozygous patients have numbers of 40 - 60% and normal patients usually have a dibucaine number of 80%. The dibucaine number is proportional to pseudocholinesterase function, but is independent of the amount of the enzyme.
Opioids currently NOT approved for epidural or intrathecal use include: A-fentanyl B- sufentanil C-morphine D-remifentanil
D-remifentanil Remifentanil is prepared in a solution of glycine, a known inhibitory neurotransmitter. Currently, remifentanil is not approved for epidural or intrathecal use.
Correct statements regarding cerebral metabolism include: A-the brain can only utilize glucose as an energy source B-forty percent of brain glucose consumption is anaerobically metabolized C-hyperglycemia can reduce the damage from focal hypoxic injury D-the adult brain consumes approximately 50 ml/min of oxygen
D-the adult brain consumes approximately 50 ml/min of oxygen. The adult brain consumes about 20% of the total body oxygen (50 ml/min). Neuronal cells normally utilize glucose as their energy source, but can also utilize ketone bodies and lactate. Hyperglycemia has been shown to worsen global and focal hypoxic brain injury.
Anesthetic management of the patient with the aortic stenosis should include: A-maintenance of a heart rate of < 50 B-spinal or epidural anesthesia if possible C-vasodilator therapy D-treatment of hypotension with phenylephrine
D-treatment of hypotension with phenylephrine Patients with severe aortic stenosis have a fixed stroke volume, and cardiac output is rate dependent. Both tachycardia and bradycardia are poorly tolerated. Vasodilation from regional anesthesia or volatile agents may precipitate severe hypotension. Treatment of hypotension should be prompt and accomplished with small doses of an alpha-stimulant such as phenylephrine.
Factors that can affect the level of an epidural anesthetic include: A. Patient weight, amount of local anesthetic injected, patient position B. Patient height, amount of local anesthetic injected, patient position C. Patient age, amount of local anesthetic injected, patient position D. B and C
D. It is currently believed that body weight alone does not influence the level of an epidural block (although extreme obesity may). Patient height (vertebral levels covered decrease with height) and age (vertebral levels covered increase with age) along with local anesthetic volume (about 1 to 2 mL local anesthetic medication per segment) and patient position (theory of gravity) can play significant roles.
To help encourage universal quality and safety practices, the ASA has adopted and mandates the use of all the following monitors during general anesthesia, except A. An oxygen analyzer B. Capnography C. Continuous visual display of an ECG D. A peripheral nerve stimulator
D. ASA standards mandate the use of pulse oximetry, capnography, an oxygen analyzer in the breathing system, disconnect alarms, a visual display of an ECG, systemic blood pressure and heart rate monitoring, and temperature monitoring (when clinically indicated) for all cases. The use of a peripheral nerve stimulator is not a mandated monitor.
You are consulted as to when a patient would be an appropriate candidate for a neuraxial block following administration of the following anticoagulant medications (patient does not have any other coagulopathies, and does not take other medications that could influence coagulation). The most correct statement is A. Last dose of ticlopidine (Ticlid) 7 days ago B. Last dose of clopidogrel (Plavix) this morning C. Last dose of abciximab (ReoPro) 24 hours ago D. Last dose of eptifibatide (Integrilin) 12 hours ago
D. According to the ASRA guidelines, waiting period for the commonly used antiplatelet agents are as follows: ticlopidine (Ticlid) 14 days, clopidogrel (Plavix) 7 days, abciximab (ReoPro) 48 hours, and eptifibatide (Integrilin) 8 hours
Compared to the Mapleson A system, the circle system A. Is less bulky B. Has a decreased risk of disconnection C. Has decreased resistance to patient breathing D. Better conserves humidity
D. Advantages of the circle system include economy (low fresh gas flow rates, decreased use of volatile agents), conservation of heat and humidity, and decreased operating-room pollution. Disadvantages of circle system include greater size, decreased portability, increased risk of disconnection, and increased resistance to patient breathing.
Blood supply to the human spinal cord includes all of the following, except: A. Blood supply to the spinal cord is from a single anterior spinal artery and two posterior spinal arteries. B. The anterior spinal artery supplies the anterior two-thirds of the spinal cord, and the posterior spinal arteries supply the posterior one-third. C. Anterior spinal artery originates from the vertebral artery. D. Posterior spinal artery originates from the posterior cerebral artery.
D. Blood supply to the spinal cord is by one anterior spinal artery and two posterior spinal arteries. The anterior spinal artery supplies the anterior two-thirds of the spinal cord, and the posterior spinal arteries supply the posterior one-third. The anterior spinal artery is branched from the vertebral artery, and the posterior spinal artery arises from the posterior inferior cerebellar artery.
As an adjuvant in epidural anesthesia, epinephrine can A. Prolong duration of blockade B. Improve the quality of blockade C. Decrease the peak plasma levels of local anesthetic concentration D. All of above
D. During epidural anesthesia, epinephrine in the dose of 5 μg/mL will improve the quality of an epidural anesthetic. Additionally, epinephrine can also prolong blockade duration, delays local anesthetic intravascular absorption, and decreases peak plasma local anesthetic concentration(s).
Capnography can help detect all of the following, except: A. Endobronchial intubation B. Esophageal intubation C. Bronchospasm D. Pulmonary embolism
D. The classic image above is commonly referred to as a curare cleft, and occurs when a patient begins to attempt inspiration during the expiratory phase of mechanical ventilation. This is one of the indications that neuromuscular function is returning.
According to the American Society of Anesthesiologists, temperature monitoring is: A. Always required B. Never required, but recommended C. Required for all general anesthetics, however not required for sedation D. Up to the discretion of the anesthesia provider.
D. The current recommendations from the American Society of Anesthesiologists state that temperature monitoring is required "when clinically significant changes in body temperature are intended, anticipated, or suspected." In addition to considering the surgical procedure, it is also important to consider at risk populations such as the elderly, infants, burn patients, and patients with autonomic dysfunction.
Evidence for the fact that leukocyte-containing blood products appear to be immunosuppressive includes all of the following, except A. Preoperative blood transfusions appear to improve graft survival in renal transplant patients B. Recurrence of malignant growths may be more likely in patients who receive a blood transfusion during surgery C. Transfusion of allogeneic leukocytes can activate latent viruses in a recipient D. Blood transfusion may decrease the incidence of serious infection following surgery or trauma
D. Blood transfusion suppresses cell-mediated immunity, which may place surgical patients at risk for postoperative infection. The association with long-term prognosis in cancer surgery is unclear, but there is a suggestion of a correlation between tumor recurrence and blood transfusions. Removing most of the white blood cells from blood and platelets (leukoreduction) reduces the incidence of nonhemolytic febrile transfusion reactions and the transmission of leukocyte-associated viruses. Preoperative blood transfusions appear to improve graft survival in renal transplant patients.
Addition of sodium bicarbonate to epidural local anesthetics may accelerate the onset of blockade with all of the local anesthetics, except A. Lidocaine B. Chloroprocaine C. Mepivacaine D. Bupivacaine
D. Bupivacaine Addition of a base with acidic local anesthetic medications will increase the amount of uncharged local anesthetic molecules injected and can therefore increase diffusion of local anesthetic molecules through the lipid layer of the cell membrane. However, sodium bicarbonate is not used with bupivacaine as it can precipitate in solutions of a pH above 6.8.
A 67-year-old patient with chronic renal failure presents for hip arthroscopy to address and treat his labral tears and associated hip pain. The best option for opioid therapy in this patient is A. Meperidine B. Codeine C. Dextropropoxyphene D. Fentanyl
D. Chronic pain is common in chronic kidney disease and most will rate their pain as moderate to severe. The absorption, metabolism, and renal clearance of opioids are complex in renal failure. However, with the appropriate selection and titration of opioids, patients with renal failure can achieve analgesia with minimal risk of adverse effects. Meperidine is not recommended in renal failure due to accumulation of normeperidine, which may cause seizures. Morphine is not recommended for chronic use in renal insufficiency due to the rapid accumulation of its active nondialyzable metabolite (morphine-6-glucuronide). Codeine has been reported to cause profound renal toxicity, which can be delayed and may occur after trivial doses. Dextropropoxyphene is associated with central nervous system and cardiac toxicity and is not recommended for use in patients with renal failure. On the other hand, fentanyl is considered relatively safe in renal failure, as it has no active metabolites.
Which of the following is a commonly used local anesthetic (LA) measurement that is analogous to the MAC of a inhaled anesthetic? A. MLAC B. MEAC C. pKa D. Cm
D. Cm The minimum concentration of a local anesthetic that will block the conduction of a nerve impulse.
While performing an axillary nerve block by both ultrasound guidance and nerve stimulator assistance, the image of your needle tip is seen posterior to axillary artery, and you observe supination of the forearm. The needle tip is closest to which of the following brachial plexus nerve branches? A. Infraclavicular nerve B. Ulnar C. Intercostal brachial nerve D. Radial nerve
D. Despite some anatomical variations within the nerve-branch distribution of the brachial plexus around the axillary artery, the radial nerve is most frequently positioned posterior to axillary artery. Stimulator of radial nerve will induce digit/wrist/elbow extension and forearm supination
5. All of the following statements regarding dextran solutions are true, except A. Dextran 40 may improve blood flow through the microcirculation B. Dextrans may have antiplatelet effects C. Large-volume infusions of dextrans have been associated with renal failure D. Dextran 40 is a better volume expander than dextran 70
D. Dextran 40 is a better volume expander than dextran 70. While dextran 40 has a molecular weight of 40,000, dextran 70 has a molecular weight of 70,000, and therefore, the latter is broken down more slowly, lasts longer, and is a better volume expander. Dextran 40 appears to improve blood flow through the microcirculation, and all dextrans may have antiplatelet effects. Infusion of large volume of dextran (>20 mL/kg/day) has been associated with renal failure.
Which of the following prevents delivery of hypoxic gas mixture once the oxygen pressure falls below 25 psi? A. Diameter index safety system B. Pin index safety system C. Inspiratory check valve D. Fail-safe valve
D. Fail-safe valve The fail-safe valve automatically closes nitrous oxide (and other gases) to prevent delivery of hypoxic gas mixture to the patient. The fail-safe valve is designed to be activated when oxygen pressure falls below 25 psi.
While taking care of a patient, you notice that the arterial monitor transducer has slipped off its stand and is hanging approximately 30 cm lower than where it was originally leveled. This would correspond to a blood pressure reading that is A. 30 mm Hg lower than the actual pressure B. 30 mm Hg higher than the actual pressure C. 22 mm Hg lower than the actual pressure D. 22 mm Hg higher than the actual pressure
D. For every 30 cm in height that a transducer is moved up and down, there is a corresponding change of 22 mm Hg in the blood pressure reading (1 cm H2O = 0.74 mm Hg).
Which of the following lung parameters IS the most important factor III postoperative pulmonary complications? A. Tidal volume B. Inspiratory reserve volume C. Vital capacity D. Functional residual capacity (FRC) E. Inspiratory capacity
D. Functional residual capacity (FRC) FRC is composed of expiratory reserve volume plus residual volume. It is essential to maximize FRC in the postoperative period to ensure that it will be greater than closing volume. Closing volume is that lung volume at which small-airway closure begins to occur. Maximizing FRC, therefore, reduces atelectasis ancl lessens the inciclence of arterial hypoxemia and pneumonia. Maneuvers aimed at increasing FRC include early ambulation, incentive spirometry, deep breathing, ancl intermittent positive pressure breathing.
All the following are true for Guillain-Barré syndrome (GBS), except A. Respiratory paralysis is frequent complication B. Presence of labile autonomic nervous system C. Ascending motor paralysis D. Exaggerated reflexes
D. GBS affects about 2/100,000 people. It is characterized by a sudden onset ascending motor paralysis, areflexia, and paresthesias. Bulbar involvement with respiratory failure is a frequent complication. Succinylcholine should be avoided in these patients, as it can cause hyperkalemia. Regional anesthesia may make GBS worse. Anesthetic management may be complicated by liability of the autonomic nervous system (hypotension or hypertension).
Which of the following patients is least likely to need calcium supplementation due to citrate-induced hypocalcemia related to blood transfusion? A. A 30-year-old trauma patient receiving massive blood transfusion through a rapid transfuser at a rate of 75 mL/min B. A patient with end-stage liver disease undergoing a complicated open shunt procedure, who is hypothermic and has received greater than 2 blood volumes of transfusion C. A neonate undergoing congenital diaphragmatic hernia repair D. A 50-year-old patient with coronary artery disease undergoing an open femoral popliteal bypass procedure, who has received 3 units of packed red blood cells
D. Hypocalcemia as a result of citrate binding of calcium is rare because of mobilization of calcium stores from the bone, and the ability of the liver to rapidly metabolize citrate to bicarbonate. Therefore, arbitrary administration of calcium in the absence of objective evidence of hypocalcemia is not indicated. Supplemental calcium may be needed when (1) the rate of blood infusion is more rapid than 50 mL/min, (2) hypothermia or liver disease interferes with the metabolism of citrate, or (3) the patient is a neonate.
Best measure to reduce cerebral oxygen consumption includes: A. Administration of barbiturates B. Hyperventilation C. Administration of opioids D. Institution of hypothermia
D. Hypothermia is one of the most effective methods for protecting the brain against ischemia. Hypothermia decreases both basal and electrical metabolic requirements throughout the brain, unlike intravenous anesthetic agents or hyperventilation.
A 70-year-old patient with chronic renal failure is in the operating room undergoing a kidney transplant. There has been more blood loss than expected, and he has received 6 units of packed red blood cells and 3 units of fresh-frozen plasma. The surgeons still complain that the patient "won't clot." All of the following are potential contributors to his coagulopathy, except A. Temperature of 34.9°C B. Uremia C. Dilutional thrombocytopenia D. Fibrinogen level of 250 mg/dL
D. Hypothermia, uremia, and dilution from massive transfusion are all potential reasons for coagulopathy in this patient. A fibrinogen greater than 150 mg/dL should be adequate for clotting.
Intraoperative anesthetic management of a patient undergoing cerebral aneurysm repair includes all, except: A. Maintenance of hypotension B. Mannitol for facilitating surgical exposure C. Maintaining mild hypothermia D. Patient remaining intubated for 24 hours postoperatively
D. Intraoperative management of cerebral aneurysms should include availability of blood, avoidance of hypertension during induction, central venous pressure and arterial blood pressure monitoring, mannitol after the dura is opened to help surgical exposure, elective hypotension as it decreases transmural pressure across the aneurysm (avoiding rupture), administration of thiopental and mild hypothermia for cerebral protection, and awake extubation depending on neurological status
You are preparing to set up for anesthesia in an off-floor location in the interventional radiology suite. The radiography equipment is consuming the limited space that is available in the suite, and therefore, the decision is made to double the extension tube length from the ventilator to the patient table. What is the impact on the dead-space ventilation that would have occurred secondary to doubling the extension tubing length? A. It would double as well B. It has been decreased to half the original volume C. It would have increased by 4-fold D. It would have not changed
D. It would have not changed. One advantage of the circle system ventilation when compared to the Mapleson system is the presence of unidirectional valves (inspiratory and expiratory valves). With the use of such valves, the volume of dead-space ventilation is limited only to that volume distal to Y-piece (including the endotracheal tube), where inspiratory and expiratory gases mix and converge, regardless of the length of tubing proximal to the Y-piece (to the anesthesia machine).
Jugular venous oxygen saturation: A. Estimates oxygen extraction B. Is unaffected by systemic hypoxia C. Involves placement of catheter through inferior vena cava. D. Monitors global oxygenation of both cerebral hemispheres
D. Jugular venous bulb oximetry involves placing a sampling catheter in the internal jugular vein (IJV). The normal range for mixed venous oxygen saturation at IJV is 50% to 75%. It gives an estimate of balance between oxygen supply and demand of the brain, and measures global cerebral oxygenation (not focal).
All the following anesthetic agents can cause seizure-like activity on the electroencephalogram (EEG), except: A. Ketamine B. Etomidate C. Enflurane D. Thiopental
D. Ketamine, etomidate, and enflurane can cause seizurelike activity on the EEG. Thiopental increases the threshold and decreases the duration of seizure activity
When measuring blood pressure manually and listening for Korotkoff sounds, the diastolic blood pressure is measured at the onset of : A. Phase 1 B. Phase 2 C. Phase 3 D. Phase 5
D. Korotkoff sounds are used to interpret blood pressure when using a stethoscope and a noninvasive blood pressure cuff, and is described in 5 phases of sound. Phase 1 heralds the onset of the first sound heard and correlates with the systolic blood pressure. Phase 5 occurs at the cuff pressure at which the sound first disappears, and is the phase recommended by the American Heart Association to correspond most reliably with the diastolic heart sound. In cases where Phase 5 does not occur (the sound never fully disappears), Phase 4 is then used to represent the diastolic blood pressure, and is described as a thumping or muting of the sound just before diastole. Phases 2 and 3 have no clinical significance.
You have just successfully performed a Bier block using 50 mL 0.5% lidocaine for carpal tunnel release surgery in a 45-year-old male (height, 6 ft; weight, 200 lb). The patient was sedated with 2 mg of midazolam upon arrival to the OR. Ten minutes following the local anesthetic placement, the surgeon indicates that the surgery is finished. At the surgeon's request, the nurse releases the tourniquet that was placed on the upper arm. The patient soon becomes agitated, and you notice twitching of the patient's arms and legs. The most likely diagnosis is A. Anaphylaxis to midazolam B. New-onset seizure disorder C. Allergic reaction to the local anesthetic D. Local anesthetic systemic toxicity (LAST)
D. LAST can occur when a large volume of local anesthetic is absorbed into or directly injected into the systemic circulation. A Bier block can provide surgical anesthesia for short procedures of the extremity, lasting 60 minutes or less. However, patients may complain of tourniquet pain that can become evident as early as 20 minutes following block performance. In order to prevent or reduce the incidence of LAST, the tourniquet needs to remain inflated and in position for a minimum of 15 to 20 minutes even if the surgical procedure finishes early. Even after 15 to 20 minutes has elapsed, cautious, intermittent, and slow release of tourniquet is recommended
The relationship between intra-alveolar pressure, surface tension, and the radius of an alveolus is described by A. Graham's law B. Beer's law C. Newton's law D. Laplace's law E. Bernoulli's law
D. Laplace's law
All of the following factors may influence the spinal level achieved during spinal anesthesia, except: A. Drug dose B. Needle direction C. Patient position at the time and immediately following injection D. Patient weight
D. Major factors influencing the level of spinal anesthesia includes baricity of local anesthetic solution, patient position immediately following spinal block placement, drug dose used, site of injection, patient age and spine anatomy, pH of the CSF, drug volume used, needle orifice direction, patient height, and patients being pregnant.
A patient with carboxyhemoglobin will have a pulse oximetry reading that A. Converges around a saturation of 85% B. Converges around a saturation of 65% C. Converges around a saturation of 45% D. Varies widely
D. Many different clinical situations will cause pulse oximetry to read in characteristic patterns. Methemoglobinemia absorbs both wavelengths of light and tends to converge around a saturation of 85%. Carboxyhemoglobin only absorbs red light, but not infrared light, and can vary widely in saturation readings. Methylene blue, a common dye used during surgery, tends to cause saturations to converge around 65%.
Contraindication(s) for neuraxial blockade include(s) A. Severe aortic stenosis B. Severe bleeding tendency C. Existing severe hypotension D. All of the above
D. Neuraxial block is a great alternative to general anesthesia for many surgical procedures below the diaphragm and an excellent choice for postoperative pain control. However, there are conditions where neuraxial block needs to be used with caution. Neuraxial blocks are associated with a sympathectomy and can therefore worsen existing hypotension and hypovolemia. Hypotension in combination with aortic and/or mitral valve stenosis may not be very well tolerated. Although spinal/epidural hematoma is rare yet possible, the risk of bleeding is significantly higher in patients with a known coagulopathy.
A patient is to undergo surgery to create an arteriovenous fistula for hemodialysis on the antecubital area of the right upper extremity. You perform a right supraclavicular block uneventfully using 20 mL 0.5% ropivacaine. The patient has a medical history significant for hypertension and end-stage renal disease. Three days following the surgery, the patient complains that she has no sensation from the right elbow to the tips of all her fingers, but she can move all of her fingers normally. The most likely etiology is A. Neurotoxicity of the trunks/divisions of the brachial plexus secondary to the ropivacaine B. Nerve injury secondary to the regional block needle used C. Prolonged effect of the local anesthetic secondary to the patient's renal failure D. Possible surgery-related injury at the elbow that may warrant an electrophysiology study
D. Neurologic injuries secondary to positional, compressional, ischemic injury often creates a more diffuse type of an injury pattern similar to the one described in the question. If the neurologic injury were due to complications from placement of a single-shot supraclavicular blockade or local anesthetic used during block placement, then these types of injuries would tend to have a more isolated pattern. Peripheral nerve block injuries from a supraclavicular block would be more likely to result in evidence of an injury pattern isolated to the trunks or divisions of the brachial plexus, and the patient would typically reveal symptoms above elbow as well. Without any adjuvant, ropivacaine block will not last as long as 72 hours.
Nitrous oxide should be avoided in patients with : A. Subdural hematoma B. Brain tumor C. Closed head injury D. Pneumocephalus
D. Nitrous oxide can diffuse into closed air spaces, which may be of significant clinical consequences. The blood/gas coefficient of nitrous oxide is 0.47, whereas that of nitrogen is 0.015. This means that nitrous oxide is about 33 times more diffusible than nitrogen. As a result, at any given partial pressure, far more nitrous oxide can be carried into a closed gas space than nitrogen removed. Thus, nitrous oxide can quickly expand closed gas spaces, such as middle ear or a pneumothorax.
Important landmarks for performing a sciatic nerve block (classic approach of Labat) include: A. Iliac crest, sacral hiatus, greater trochanter B. Iliac crest, coccyx, and greater trochanter C. Posterior superior iliac spine, coccyx, and greater trochanter D. Posterior superior iliac spine, greater trochanter and sacral hiatus E. Posterior superior iliac spine and greater trochanter
D. Posterior superior iliac spine, greater trochanter and sacral hiatus. To perform a sciatic nerve block, first draw a line from the posterior superior iliac spine to the greater trochanter, then draw a 5-cm line perpendicular from the midpoint of this line caudally and a second line from the sacral hiatus to the greater trochanter. The intersection of the second line with the perpendicular line marks the point of entry.
Which of the following local anesthetics used for intravenous regional anesthesia (Bier block) is most rapidly metabolized and thus least toxic? A. Lidocaine B. Ropivacaine C. Mepivacaine D. Prilocaine E. Etidocaine
D. Prilocaine Prilocaine is the most rapidly metabolized of the amide local anesthetics and therefore least toxic. 2-Chloroprocaine is hydrolyzed rapidly in the blood and, therefore, would appear to be ideal, but it has been associated with a high incidence of thrombophlebitis and is therefore not recommended. To avoid toxicity, maximum doses are as follows: prilocaine, 3 to 4 mglkg; lidocaine, 1.5 to 3 mglkg; ropivacaine, 1.2 to 1.8 mglkg.
While performing a peripheral nerve block in an awake patient, access and/or use of all of the following should be considered mandatory, except A. Administer supplemental oxygen B. Apply standard ASA monitors C. Access to resuscitation medications and equipment D. Immediate access to a mechanical ventilator.
D. Regional anesthesia should be administered in a monitored location where standard ASA monitors. Supplemental oxygen along with resuscitative medications and equipment should be readily accessible and immediately available. However, immediate access to a functioning anesthesia ventilator is not always necessary.
The effect of ischemia on somatosensory-evoked potentials (SSEPs) is A. Decreased latency, decreased amplitude B. Increased latency, increased amplitude C. Decreased latency, increased amplitude D. Increased latency, decreased amplitude
D. SSEPs reflect the integrity of neuronal pathway from the peripheral nerves through the spinal cord (dorsal columns) to the brain. SSEPs are electrical manifestations of the central nervous system response to external stimulation. Intraoperative changes in amplitude or latency or complete loss of waveforms are indicators of compromised sensory pathway integrity. SSEP amplitude loss greater than 50% or a latency increase greater than 10% is considered significant.
A 56-year-old patient with a history of liver disease and osteomyelitis is anesthetized for tibial debridement. After induction and intubation the wound is inspected and debrided with a total blood loss of 300 mL. The patient is transported intubated to the recovery room, at which time the systolic blood pressure falls to 50 mm Hg. Heart rate is 120/minute, arterial blood gases CABGs) are Páo 103, Pacó 45, pH 7.3, with 97% Ó saturation with 100% FI02• Mixed venous blood gases are Pvó 60, Pvcó 50, pH 7.25, with 90% Ó saturation. Which of the following diagnoses is most consistent with this clinical picture? A. Myocardial infarction B. Congestive heart failure C. Cardiac tamponade D. Sepsis with acute respiratory distress syndrome E. Hypovolemia
D. Sepsis with acute respiratory distress syndrome All hypotension can be broadly broken down in to two main categories: decreased cardiac output and decreased systemi c vascu lar resistance. Flow or cardiac output can be furthe r subdi vided into problems related to decreased heart rate (i.e., bradycardi a versus problems related to decreases in stroke volume. A mi xed venous arterial oxygen level of 60 mm Hg in the absence of factors that wou ld decrease periphe ral uptake (e.g., cyanide) would represent a signifi cant increase in cardiac output. Normal Po, in mixed venous blood is 40 mm Hg. The other choices in this question all represent conditions whe reby cardi ac output is diminished and consequently would not be consistent with the data given in the question
A 30-year-old male patient without preoperative renal dysfunction is undergoing a primary orthotopic liver transplant (OLT) for failure due to inherited α1-antitrypsin deficiency. During cross-clamping of the suprahepatic inferior vena cava (IVC), the most accurate effect created by use of venovenous bypass (VVB) is that it A. Induces urinary retention B. Prevents metabolic acidosis C. Requires heparinization D. Supports cardiac output
D. Standard technique of OLT causes changes in hemodynamics during the anhepatic phase because of cross-clamping of the suprahepatic IVC. Interruption of the IVC and portal vein flow causes a decrease in preload, cardiac output, and arterial blood pressure. VVB has been used to achieve hemodynamic stability by avoiding venous congestion, promoting venous return with decrease incidence of renal dysfunction.
The main advantage of neurolytic nerve blockade with phenol versus alcohol is A. Denser blockade B. Blockade is permanent C. The effects of the block can be evaluated immediately D. The block is less painful E. Phenol is selective for sympathetic fibers
D. The block is less painful Neurolytic blockade with phenol (6% to 10% in glycerine) is painless because phenol has a dual action as both a local anesthetic and a neurolytic agent. The initial block wears off over a 24-hour period, during which time neurolysis occurs. For this reason one must wait a day to determine effectiveness of the neurolytic block. Alcohol (100% ethanol) is painful on injection and should be preceded by local anesthetic injection. Unfortunately there is no neurolytic agent that affects only sympathetic fibers.
Each of the following statements about the preoperative management of an adrenal pheochromocytoma is true, except A. Adequate blockade can be assessed by in-house blood pressures <160/90 mm Hg for 24 hours prior to surgery B. β-Blockers should be administered only in conjunction with adequate αblockade C. Administration of α-blocker can decrease operative mortality D. Nasal congestion is a sign of inadequate α-adrenergic block
D. The most critical element to safe perioperative care of the pheochromocytoma patient is adequate preoperative blockade against the effects of the circulating catecholamines. The main goals of preoperative blockade are to normalize blood pressure and heart rate, restore volume depletion, and prevent surgery-induced catecholamine storm. A sign of adequate α-blockade is the development of nasal congestion due to smooth-muscle relaxation of nasal mucosal arterioles
The fastest measure to decrease intracranial pressure (ICP) in a patient is A. Mannitol B. Dexamethasone C. Furosemide D. Hyperventilation
D. The quickest way to reduce ICP in a patient is hyperventilation, often to a PaCÓ of 25 mm Hg. Reduced PaCÓ (hypocarbia) causes cerebral vasoconstriction leading to a reduction in cerebral blood flow and cerebral blood volume. However, hyperventilation is only used as a temporizing measure only in periods of acute raised ICP
A properly performed lumbar plexus block will result in blockade of all the following nerve branches, except A. Femoral nerve B. Lateral femoral cutaneous nerve C. Obturator nerve D. Sciatic nerve
D. The three major nerve branches of the lumbar plexus that are affected by such a block include femoral, lateral femoral cutaneous, and obturator nerves. Sciatic nerve originates from the sacral plexus and is not part of the lumber plexus.
Which of the following nerves is typically spared during performance of an interscalene brachial plexus block? A. Median B. Axillary C. Musculocutaneous D. Ulnar.
D. The ulnar nerve branch originates from the C8-T1 nerve roots. Properly performed interscalene approach to brachial plexus blockade can provide for a dense blockade of the C5-C7 nerve roots/trunks and less consistent blockade of the C8-T1 nerve roots/trunks. Therefore, an interscalene approach to blockade of the brachial plexus for distal upper extremity surgical procedures may not be the most ideal approach.
The anesthesiologist is called to the emergency room by the pediatrician to help manage a 3-year-old boy with a high fever and upper airway obstruction. His mother states that earlier that afternoon he complained of a sore throat and hoarseness. The patient is sitting erect and leaning forward, has inspiratory stridor, tachypnea, and sternal retractions, and is drooling. Which of the following is the most appropriate management of airway obstruction in this patient? A. Aerosolized racemic epinephrine B. Awake tracheal intubation in the emergency room C. Transfer to the OR and awake tracheal intubation D. Transfer to the OR, inhalation induction, and tracheal intubation E. Transfer to the OR, IV induction, paralysis with succinylcholine, and tracheal intubation
D. Transfer to the OR, inhalation induction, and tracheal intubation. This history is consistent with an acute life-threatening cause of upper airway obstruction called epiglottitis (or more appropriately supraglottitis because other supraglottic structures are involved as well). In the past it was caused most often by Haemophilus injluenzae. With widespread immunization against H. injluenzae this condition has become much less frequent and the primary causes now are Neisseria meningitidis, group A Streptococcus, and Candida albicans. This condition is a medical emergency that can progress to respiratory obstruction in just a few hours. When suspected, the anesthesiologist and otolaryngologist should be notified and the child immediately transferred to the OR (with the parent if appropriate) before complete upper airway obstruction ensues. In the OR, anesthesia should be induced with halothane or sevoflurane and oxygen with the child in a sitting position. Halothane or sevoflurane are less likely to induce laryngospasm than enflurane, isoflurane, or desflurane. IV access should be established as soon as the child is deeply anesthetized. Atropine should be administered to block vagally mediated bradycardia induced by direct laryngoscopy. Muscle relaxants are contraindicated because they can cause complete obstruction of the upper airway in these patients. The trachea should be intubated under direct laryngoscopy when the depth of anesthesia is sufficient to blunt laryngeal reflexes.
During placement of an epidural in a 78-year-old patient scheduled for a total knee arthroplasty, the patient complains of a sharp sustained pain radiating down his left leg as the catheter is inserted to 2 cm. The most appropriate action at this time would be A. Leave the catheter at 2 cm, give test dose B. Give small dose to relieve pain then advance 1 cm C. Withdraw the catheter 1 cm, give test dose D. Withdraw needle and catheter, reinsert in a new position E. Abandon epidural technique, place long-acting spinal anesthetic
D. Withdraw needle and catheter, reinsert in a new position When an epidural catheter is placed without fluoroscopic guidance, the exact location of the needle tip relative to the anatomic structures of the back can only be surmised. If malposition of either the needle or the catheter is suspected, it is prudent to withdraw the entire apparatus and reinsert a second time. In this case, it is possible that the catheter tip has found its way into a nerve root. Under these circumstances, injection of a local anesthetic or narcotic could produce pressure that would lead to ischemia and possible neurologic damage. During placement or injection of an epidural catheter, a paresthesia is always a warning sign that should be heeded.
Remifentanil is metabolized primarily by (Choose all that apply) A. Kidneys B. Liver C. Hoffman elimination D. Pseudocholinesterase E. Nonspecific esterases
E-only Remifentanil is a ultrashort-acting narcotic. Chemically it is a derivative of piperidine (like fentanyl),but remifentanil has an ester linkage and is rapidly broken down by nonspecific plasma as well as tissue esterases. The elimination half-life is less than 20 minutes and is best administered by a continuous infusion. Pseudocholinesterase deficiency or renal or hepatic failure does not affect remifentanil's rapid metabolism.
What is the PA02 of a patient on room air in Denver, Colorado (assume a barometric pressure of 630 mm Hg, respiratory quotient of 0.8, and Pacó of 34 mm Hg)? A. 40mmHg B. 50mmHg C. 60mmHg D. 70mmHg E. 80 mm Hg
E. 80 mm Hg. Where PB is the barometric pressure (mm Hg), FIó is the fraction of inspired Ó, Pacó is the arterial CÓ tension (mm Hg), and R is the respiratory quotient.
Which of the following muscles of the larynx is innervated by the external branch of the superior laryngeal nerve? A. Vocalis muscle B. Thyroarytenoid muscles C. Posterior cricoarytenoid muscle D. Oblique arytenoid muscles E. Cricothyroid muscle
E. Cricothyroid muscle All the other muscles of the larynx are innervated by the recurrent laryngeal nerve
A retrobulbar block anesthetizes each of the following nerves EXCEPT: A. Ciliary nerves B. Cranial nerve IV (trochlear nerve) C. Cranial nerve III (oculomotor nerve) D. Cranial nerve VI (abducens nerve) E. Maxillary branch of the trigeminal nerve
E. Maxillary branch of the trigeminal nerve. A retrobulbar block anesthetizes the three cranial nerves responsible for movement of the eye. The ciliary nerves are also blocked, providing anesthesia to the conjunctiva, cornea, and uvea. The ophthalmic branch of the trigeminal nerve provides sensory innervation to the skin of the forehead, cornea, and eyelid. This branch of the trigeminal nerve may be blocked, but the maxillary branch would be spared .
Which of the following would have the greatest effect on the level of sensory blockade after a subarachnoid injection of isobaric 0.75% bupivacaine? A. Coughing during placement of the block B. Addition of epinephrine to the local anesthetic solution C. Barbotage D. Patient weight E. Patient position
E. Patient position Many factors have an effect on the sensory level after a subarachnoid injection. The baricity of the solution and the patient position are the most important determinants of sensory level. The other listed options have little to no effect on sensory level. Patient height also has little effect on sensory level.
A 63-year-old woman undergoes total knee arthroplasty under spinal anesthesia. Two days later she complains of a severe headache on the left side of her head. Pain intensity is not related to posture. The LEAST likely cause of this headache is A. Caffeine withdrawal B. Malingering C. Viral illness D. Migraine E. Postdural puncture headache
E. Postdural puncture headache Postdural puncture headache will have a postural component. The headache pain is typically frontal or occipital in location.
The anterior and posterior spinal arteries originate from the: A. Common carotid and vertebral arteries, respectively B. Internal carotid and vertebral arteries, respectively C. Internal carotid and posterior cerebral arteries, respectively D. Vertebral and anterior cerebellar arteries, respectively E. Vertebral and posterior inferior cerebellar arteries, respectively
E. Vertebral and posterior inferior cerebellar arteries, respectively. The posterior spinal arteries are paired; they arise from the posterior inferior cerebellar arteries and have 25 to 40 radicular arteries. The anterior spinal artery is a single midline artery that arises from the union of a branch of each vertebral artery. It descends in front of the anterior longitudinal sulcus of the spinal cord. This single artery is also fed by numerous radicular arteries.
Characteristics of omphalocele include: (Select 2) A- location lateral to the umbilicus B- lacks a hernia sac C- results from the failure of midgut migration into the abdomen. D- nitrous oxide should be used during the repair to ensure a rapid emergence. E- association with trisomy 21 F- results from abnormal development of the right omphalomesenteric artery.
E. association with trisomy 21. F. Results from the failure of midgut migration into the abdomen. Gastroschisis and omphalocele are characterized by defects in the abdominal wall that allow herniation of the viscera. Omphaoceles occur at the base of the umbilicus, have a hernia sac and are commonly associated with other anomalies. In contrast, gastroschisis is usually lateral to the umbilicus, lacks a hernia sac and is usually an isolated finding. Nitrous oxide is best avoided during repair as it may result in bowel distention making closure more difficult.
A 62-year-old male is brought to the ICU after elective repair of an abdominal aortic aneurysm. His vital signs are stable, but he requires a sodium nitroprusside infusion at a rate of 10 flg/kg/min to keep the systolic blood pressure below I 10 mm Hg. The Sao, is 98% with controlled ventilation at 12 breaths/ min and an FlO, of 0.60. After 3 days, his Sao, decreases to 85% on the pulse oximeter. Chest x-ray and results of physical examination are unchanged. Which of the following would most likely account for this desaturation? A. Cyanide toxicity B. Thiocyanate toxicity C. Ó toxicity D. Thiosulfate toxicity E. Methemoglobinemia
E.) Methemoglobinemia The metabolism of nitroprusside in the body requires the conversion of oxyhemoglobin (Fe++) to methemoglobin (Fe+++). The presence of sufficient quantities of methemoglobin in the blood will cause the pulse oximeter to read 85% saturation regardless of the true arterial saturation. Cyanide toxicity is also a possibility in any patient who is receiving nitroprusside. Cyanide toxicity should be suspected when the patient develops metabolic acidosis or becomes resistant to the hypotensive effects of this drug despite a sufficient infusion rate. This can be confirmed by measuring the mixed venous PaD" which would be elevated in the presence of cyanide toxicity. Thiocyanate toxicity is also a potential hazard of nitroprusside administration in patients with renal failure. Patients suffering from thiocyanate toxicity display nausea, mental confusion, and skeletal-muscle weaknes
Potential complication(s) of a stellate ganglion block include (Choose all that apply). 1. Recurrent laryngeal nerve paralysis 2. Subarachnoid block 3. Brachial plexus block 4. Pneumothorax
E.ALL All of the choices are potential complications of stellate ganglion blockade. Others include accidental injection of the local anesthetic into a vertebral artery resulting in seizure and inadvertent cervical epidural
Local anesthetics with the potential to form methemoglobin include: (Select 3) EMLA topical anesthetic cream bupivacaine benzocaine ropivacaine prilocaine mepivacaine
EMLA topical anesthetic cream, prilocaine, benzocaine EMLA cream contains both lidocaine and prilocaine. The metabolites of prilocaine can convert hemoglobin to methemoglobin. Benzocaine can also cause methemoglobinemia.
A 49-year-old patient with a long history of dull aching pain in the right lower extremity receives a spinal anesthetic with 100 mg of procaine with 5% dextrose. The patient reports no relief in symptoms but has complete bilateral motor blockade. What diagnosis is consistent with this differential blockade examination? (Choose all that apply) I. Central pain 2. Myofascial pain 3. Malingering 4. Complex regional pain syndrome T (reflex sympathetic dystrophy)
I. Central pain, 3. Malingering. Somatic pain in the extremities is relieved with spinal anesthesia. If a patient fails to obtain pain relief despite complete sympathetic, sensory, and motor blockade, a "central" mechanism for the pain is likely or the lesion causing the pain is higher in the CNS than the level of blockade achieved by the spinal. Central pain states may include encephalization, psychogenic pain, or malingering. Persistence of pain in the lower extremities after successful spinal blockade suggests a central source or psychological source of pain.
An 18-year-old man has a seizure during placement of an interscalene brachial plexus block with 2% lidocaine. The anesthesiologist begins to hyperventilate the patient's lungs with 100% Ó using an anesthesia bag and mask. The rationale for this therapy is to : (Choose all that apply) I. Decrease delivery of lidocaine to the brain 2. Prevent hypoxia 3. Hyperpolarize the nerve membranes 4. Convert of lidocaine to the protonated (ionized) form.
I. Decrease delivery of lidocaine to the brain 2. Prevent hypoxia 3. Hyperpolarize the nerve membranes . During a seizure, administration of 100% Ó helps to prevent hypoxia in a patient who otherwise might not be breathing. Hyperventilation induces hypokalemia and respiratory alkalosis, both of which result in hyperpolarization of nerve membranes and elevation of the seizure threshold. Hyperventilation also causes cerebral vasoconstriction and decreased delivery of local anesthetic to the brain. Hyperventilation also raises the patient's pH (respiratory alkalosis) and converts lidocaine into the nonionized (nonprotonated) form, which crosses the membrane easily. This has no beneficial effect.
A 45-year-old man is undergoing a posterior cervical fusion in the sitting position. Induction of anesthesia and tracheal intubation are uneventful. Anesthesia is maintained with N20, 50% in 02' and enflurane. Suddenly, air is heard on the precordial Doppler ultrasound. Other observations consistent with VAE include::(Choose all of the questions that are correct). I. Decreased Páo 2. Increased end-tidal nitrogen 3. Decreased arterial blood pressure 4. Decreased Pacó
I. Decreased Páo 2. Increased end-tidal nitrogen 3. Decreased arterial blood pressure Progressive entrainment of air into the pulmonary micro-circulation reduces lung perfusion and increases pulmonary vascular resistance and alveolar dead-space ventilation. The increase in pulmonary vascular resistance is reflected by increases in pulmonary arterial and central venous pressures. A large air embolus can result in right ventricular outflow obstruction, which will dramatically reduce cardiac output, resulting in systemic hypotension. Increased alveolar dead space results in a decrease in PEC02• In severe VAE, CÓ cannot be eliminated and Pacó increases. PÉN increases because air diffuses into the pulmonary alveoli. The sensitivity of continuous PEC02 monitoring is similar to that for continuous PÉN monitoring.
Which of the following can result in excessive overflow of gas from the scavenging system reservoir bag? (Select all the correct answers). I. High fresh gas now into the patient breathing circuit. 2. A positive end expiratory pressure (PEEP) valve located in the patient breathing circuit 3. A scavenging system interfrace not connected to the wall suction. 4. Excessive suction applied to the scavenging system interface.
I. High fresh gas now into the patient breathing circuit. 3. A scavenging system interfrace not connected to the wall suction. Excessive overflow of gas from the scavenging system reservoir bag into the OR atmosphere can result from several causes. The most common causes are excessive fresh gas flow into the patient breathing circuit, kinking or obstruction of the tubing to the wall suction (e.g., by the wheels of the anesthesia machine), and failure to connect the scavenging system interface to wall suction. These malfunctions will not result in excessive pressure buildup within the patient breathing circuit if a positive-pressure relief valve is incorporated into the scavenging system interface and is functioning correctly.
The saturated vapor pressure of volatile anesthetics (Select all the correct answers). I. Is dependent on the temperature of the liquid. 2. Is dependent on the atmospheric pressure above the liquid. 3. Decreases during use of the vaporizer. 4. Increases during use or the vaporizer.
I. Is dependent on the temperature of the liquid. 3. Decreases during use of the vaporizer. The saturated vapor pressure of a liquid within a closed container is that pressure produced by the molecules in the vapor phase when they collide with each other and the walls of the container. This pressure is directly proportional to the temperature of the liquid. As the volatile becomes vaporized in the vaporizer, the temperature falls as this is an endothermic reaction.
In the first few hours after cessation of halothane anesthesia, halothane concentration in the blood falls because it: (Choose all that apply) I. Is excreted via the lungs 2. Is taken up by the vessel-poor group 3. Is metabolized by the liver 4. Is excreted unchanged by the kidney
I. Is excreted via the lungs 2. Is taken up by the vessel-poor group 3. Is metabolized by the liver Upon termination of an anesthetic, volatile concentrations in the vessel-rich group may approximate alveolar concentrations. However, equilibrium may not be reached in the muscle group until several hours of anesthetic administration have elapsed. Considerably more time is necessary for equilibrium to occur in fat. Upon termination of anesthesia, higher concentrations of anesthetic will be seen in the blood relative to the concentrations in fat and other poorly perfused tissues. The concentration gradient therefore will be favorable to continue uptake into the vessel-poor tissues even as halothane is excreted via the lungs and metabolized by the liver. Excretion of unchanged drug by the kidney is insignificant.
Of the following arrangements of rotameters on the anesthesia machine, which is(are) safe (gas now is from left to right)? (Select all the correct answers). I. N20 , air, Ó 2. 02, air, N20 3. Air, N20 , 02 4. Air, 02, N20
I. N20 , air, Ó 3. Air, N20 , 02 The last gas added to a gas mixture should always be 02' This arrangement is the safest because it assures that leaks proximal to the 02 inflow cannot result in delivery of a hypoxic gas mixture to the patient. With this arrangement (02 added last), leaks distal to the 02 inflow will result in a decreased volume of gas, but the FI02 will not be reduced
CMR is increased by (Choose all of the questions that are correct). I. Seizure 2. Hyperthermia 3. Ketamine 4. Isoflurane
I. Seizure 2. Hyperthermia 3. Ketamine In contrast to ketamine and increased neural activity (e.g., seizures or hyperthermia), which increase CBP and CMR, volatile anesthetics cause a simultaneous, dose-dependent increase in CBP and decrease in CMR (Le., volatile anesthetics "uncouple" global CBP and CMR
Match each region of the adrenal gland with the class of hormones it produces. a. adrenal medulla b. zona fasciculata c. zona reticularis d. zona glomerulosa 1. catecholamines 2. glucocorticoids 3. androgens 4. mineralocorticoids
Medulla= catecholamines Glomerulosa= Mineralcorticoids Fasciculata= Glucocorticoirds Reticularis= Androgens
Neuraxial anesthesia is MOST appropriate for which of the following patients? (A)-A 32-year-old woman patient receiving a recombinant hirudin derivative (desirudin, lepirudin) due to previous heparin induced thrombocytopenia. B-A 55-year-old woman undergoing total hip arthroplasty who is receiving aspirin 325mg bid (C)A 70-year-old man who had a drug-eluting stent placed 6-months ago and continues on clopidogrel therapy (D)A 75-year-old man who stopped coumadin 3 days ago and the INR is pending
Nonsteroidal anti-inflammatory drugs seem to represent no added significant risk for the development of spinal hematoma in patients having epidural or spinal anesthesia. Nonsteroidal anti-inflammatory drugs (including aspirin) do not create a level of risk that will interfere with the performance of neuraxial blocks. Caution should be used when performing neuraxial techniques in patients recently discontinued from long-term warfarin therapy. In the first 1 to 3 days after discontinuation of warfarin therapy, the coagulation status (reflected primarily by factor II and X levels) may not be adequate for hemostasis despite a decrease in the INR (indicating a return of factor VII activity). Adequate levels of II, VII, IX, and X may not be present until the INR is within reference limits. We recommend that the anticoagulant therapy must be stopped (ideally 4-5 days before the planned procedure) and the INR must be normalized before initiation of neuraxial block. On the basis of labeling and surgical reviews, the suggested time interval between discontinuation of thienopyridine therapy and neuraxial blockade is 14 days for ticlopidine and 7 days for clopidogrel. Recombinant hirudin derivatives, including desirudin (Revasc), lepirudin (Refludan), and bivalirudin (Angiomax) inhibit both free and clot-bound thrombin. Argatroban (Acova), an l-arginine derivative, has a similar mechanism of action. These medications are indicated for the treatment and prevention of thrombosis in patients with heparin-induced thrombocytopenia and as an adjunct to angioplasty procedures. There is no "antidote"; the antithrombin effect cannot be reversed pharmacologically. Although there are no case reports of spinal hematoma related to neuraxial anesthesia among patients who have received a thrombin inhibitor, spontaneous intracranial bleeding has been reported.
Neuraxial anesthesia is MOST appropriate for which of the following patients? A-A 32-year-old woman patient receiving a recombinant hirudin derivative (desirudin, lepirudin) due to previous heparin induced thrombocytopenia. B-A 55-year-old woman undergoing total hip arthroplasty who is receiving aspirin 325mg bid C-A 70-year-old man who had a drug-eluting stent placed 6-months ago and continues on clopidogrel therapy D-A 75-year-old man who stopped coumadin 3 days ago and the INR is pending
Nonsteroidal anti-inflammatory drugs seem to represent no added significant risk for the development of spinal hematoma in patients having epidural or spinal anesthesia. Nonsteroidal anti-inflammatory drugs (including aspirin) do not create a level of risk that will interfere with the performance of neuraxial blocks. Caution should be used when performing neuraxial techniques in patients recently discontinued from long-term warfarin therapy. In the first 1 to 3 days after discontinuation of warfarin therapy, the coagulation status (reflected primarily by factor II and X levels) may not be adequate for hemostasis despite a decrease in the INR (indicating a return of factor VII activity). Adequate levels of II, VII, IX, and X may not be present until the INR is within reference limits. We recommend that the anticoagulant therapy must be stopped (ideally 4-5 days before the planned procedure) and the INR must be normalized before initiation of neuraxial block. On the basis of labeling and surgical reviews, the suggested time interval between discontinuation of thienopyridine therapy and neuraxial blockade is 14 days for ticlopidine and 7 days for clopidogrel. Recombinant hirudin derivatives, including desirudin (Revasc), lepirudin (Refludan), and bivalirudin (Angiomax) inhibit both free and clot-bound thrombin. Argatroban (Acova), an l-arginine derivative, has a similar mechanism of action. These medications are indicated for the treatment and prevention of thrombosis in patients with heparin-induced thrombocytopenia and as an adjunct to angioplasty procedures. There is no "antidote"; the antithrombin effect cannot be reversed pharmacologically. Although there are no case reports of spinal hematoma related to neuraxial anesthesia among patients who have received a thrombin inhibitor, spontaneous intracranial bleeding has been reported.
Match each laboratory test with its underlying pathology. a. PT b. 5'-nucleotidase c. transaminases d. bilirubin 1. hepatocellular injury 2. biliary obstruction 3. synthetic function 4. hepatic clearance
PT= synthetic function 5'-nucleotidase= biliary obstruction transaminases= hepatocellular injury bilirubin= hepatic clearance
Signs and symptoms of intracranial hypertension include:(Choose all of the questions that are correct). 1. Papilledema 2. Headache 3. Nausea and vomiting 4. Decreased mentation
Signs and symptoms of intracranial hypertension include nausea and vomiting, systemic hypertension, bradycardia, altered level of consciousness, irregular breathing pattern, papilledema, seizure activity, personality changes, and coma.
An otherwise healthy 75-year-old man taking no medications undergoes an uneventful spinal anesthetic with lidocaine for an outpatient cystoscopy. The next day, the patient calls complaining of excruciating lower back pain that radiates down both legs. Which if the following is MOST appropriate action? A-Have the patient see his urologist for examination, as the pain is secondary to the lithotomy position. B-If no other symptoms are present, reassure the patient that this pain will improve in a few days C-Order a spine MRI D-Obtain an immediate neurological consultation.
These are common symptoms associated with TNS (transient neurologic symptoms) and are associated with lidocaine spinals, specifically in the lithotomy position. The symptoms usually improve with NSAIDs and resolve in a few days. An MRI would be the most useful test if you suspect a neuraxial hematoma. A neuraxial hematoma is extremely rare, especially in patients with no risk factors and those not receiving anticoagulants. Symptoms of a neuraxial hematoma are generally increased sensory/motor block and/or bowel and bladder dysfunction. Neuraxial hematomas do not typically present with severe radicular pain. The patient should be encouraged to call his urologist or anesthesiologist if the pain does not improve or worsens over the next day or two.
The PRC is composed of the A. Expiratory reserve volume and residual volume B. Inspiratory reserve volume and residual volume C. Inspiratory capacity and vital capacity D. Expiratory capacity and tidal volume E. Expiratory reserve volume and tidal volume
[] A -Expiratory reserve volume and residual volume. comprehensive understanding of respiratory physiology is important for understanding the effects of both regional and general anesthesia on respiratory mechanics and pulmonary gas exchange. The volume of gas remaining in the lungs after a normal expiration is called thefllncliona! residual capacity. The volume of gas remaining in the lungs after a maximal expiration is called the residllal lIolllllle. The difference between these two volumes is called the expiratol), resell'e lIolllllle. Therefore, the FRC is composed of the expiratory reserve volume and residua
Define each term. a. A drug that activates or stimulates receptors. b. The absorption, distribution, metabolism, and excretion of inhaled or injected drugs. c. The responsiveness of receptors to drugs, and the mechanism by which drugs cause these effects to occur. d. A drug that binds to receptors to prevent exogenous or endogenous substances from activating them. e. An effect produced by 2 drug acting together that is greater than would occur for each drug alone. f. Calculation by which a dose of a drug is administered by IV and is divided by the plasma concentration to reflect the apparent volumes of the drug into various intercellular compartments. g. A transmembrane protein macromolecule that acts as a mechanism for a drug to bind to and exert its effect. h. Reflects the concentration of an inhaled anesthetic measured at 1 atmosphere in the body that prevents skeletal muscle movement in response to noxious stimulus like a surgical incision. i. Characterized by differences in potency, slope, efficacy, and individual responses, it depicts the relationship between the dose of a drug administered or plasma concentration, and the resulting pharmacological effect.
a = agonist b= pharamacokinetics. c= pharmacodynamics. d= Antagonist e= synergistic f= Volume of Distribution. g= Receptor h= Minimal Alveolar Concentration i= Dose- Response Curve.
Which of the following is true regarding the IV loading dose of a drug? a- It is used to achieve effective target concentration immediately. b- A drug with a shorter half-life will lead to a long half-life in a bolus dose. c- It may lead to underdosing d- It should not be chosen based on volume of distribution.
a- It is used to achieve effective target concentration immediately. A loading dose is employed to attempt to achieve a therapeutic plasma concentration in a shorter period of time. Essentially, this is accomplished by administration of a dose determined by the product of the targeted concentration and the volume of distribution of that drug.
Correct statements concerning the use of benzodiazepines in the elderly include: a-volume of distribution is increased b-reduced pharmacodynamic sensitivity is observed c- the elimination half-life of diazepam, but not midazolam, is increased. d-all of the above
a-volume of distribution is increased Aging increases the volume of distribution for all benzodiazepines, effectively prolonging their elimination half-times. Enhanced pharmacodynamic sensitivity is also observed. The elimination half-times of both diazepam and midazolam are increased.
Select the most effective weight loss procedure for the patient with morbid obesity? a. Roux-en-Y gastric bypass b. gastric banding c. gastric sleeve d. biliopancreatic diversion with duodenal switch
a. Roux-en-Y gastric bypass
Select the true statement regarding the primary mechanism of action of local anesthetics. a. The conjugate acid binds to the intracellular portion of the Na channel b. The conjugate acid binds to the extracellular portion of the Na channel c. The uncharged base binds to the intracellular portion of the Na channel d. The uncharged base binds to the extracellular portion of the Na channel
a. The conjugate acid binds to the intracellular portion of the Na channel LA are weak bases. When they are placed into solution, they dissociate into an uncharged base & its conjugate acid -The uncharged base form is required for it to gain entry inside the cell. Once inside, the conjugate acid binds to the Na channel.
In the obese patient, which of the following are expected to increase? (select 2) a. Volume of distribution of lipophilic drugs b. circulation time c. MAC d. volume distribution of hydrophilic drugs
a. Volume of distribution of lipophilic drugs (d/t larger fat mass) d. volume distribution of hydrophilic drugs (d/t larger muscle mass & blood volume)
Which drugs obey zero order kinetics?(select 2) a. aspirin b. propofol c. midazolam d. alcohol
a. aspirin d. alcohol
Identify the best tests of tubular function (select 2) a. fractional excretion of Na b. creatinine clearance c. urine osmolality d. BUN
a. fractional excretion of Na c. urine osmolality -Tests of GFR: BUN & CrCl -Tests of tubular function: fractional excretion of Na & urine osmolality
Select the statements that best describe hepatitis. (select 2) a. halothane hepatitis is an immune-mediated response b. ETOH abuse is the most common cause of chronic hepatitis c. Hepatitis A usually causes cirrhosis d. Hepatitis is usually transmitted via blood transfusion
a. halothane hepatitis is an immune-mediated response b. ETOH abuse is the most common cause of chronic hepatitis -Hep B & C, not A causes cirrhosis -Hep A is most common form of viral hepatitis
When compared to post junctional nicotinic receptors, exntrajunctional nicotinic receptors: (select 2) a. have gamma subunit in lieu of an epsilon subunit b. are most resistant to succinylcholine c. remain open for a longer period d. are inhibited following SCI
a. have gamma subunit in lieu of an epsilon subunit c. remain open for a longer period more sensitive to succ
All of the following additives prolong the duration of local anesthetics except: a. hyaluronidase b. epinephrine c. dexamethasone d. dextran
a. hyaluronidase Hyaluronic acid is present in the interstitial matrix & basement membrane. It hinders the spread of substances through tissue. Hyaluronidase hydrolyzes hyaluronic acid, which facilitates diffusion of substances in the tissues
Which drugs should be avoided in the patient with carcinoid syndrome? (select 3) a. ketamine b. rocuronium c. norepinephrine d. vasopression e. morphine f. ocreotide
a. ketamine c. norepinephrine e. morphine -Avoid drugs that release histamine(morphine), stimulate SNS (ketamine), or augment hormone release (NE)
Which statement illustrates the best understanding of benzodiazepines? a. lorazepam is more potent than diazepam b. midazolam can produce isoelectric EEG c. diazepam provides retrograde amnesia d. midazolam solubility is enhanced by propylene glycol
a. lorazepam is more potent than diazepam
Which hormones are released by the anterior pituitary gland? (select 3) a. luteinizing hormone b. antidiuretic hormone c. Corticotropin-releasing hormone d. growth hormone e. prolactin f. oxytocin
a. luteinizing hormone d. growth hormone e. prolactin FLATPIG: FSH, LH, adrenocotricotropin, TSH, Prolactin, ignore, GH Posterior pituitary: ADH, oxytocin
Goals of drug combinations include all of the following except: a - decreased toxicity b- increased duration of action c- increased efficacy d- maintenance of efficacy
b- increased duration of action [The primary goal of combining drugs centers on maximizing the benefits derived from the drug while minimizing the adverse events they may produce].
What variables are related by the Frank-Starling mechanism? a. CVP & MAP b. PAOP & SV c. contractility & CO d. LVEDP & SVR
b. PAOP & SV Frank-Starling mechanism relates ventricular volume to ventricular output. In this question, the best choice is PAOP (Ventricular volume) & SV (ventricular output)
Considerations for the CV effects of morbid obesity include: (select 2) a. tachycardia b. diastolic dysfunction c. increased venous return d. increased EKG voltage
b. diastolic dysfunction c. increased venous return
Which agent is most likely to increase risk in patient with history of acute intermittent porphyria? a. dexmedetomidine b. etomidate c. propofol d. ketamine
b. etomidate
___________________ states that the rate of change of the amount of a drug at any given time is proportional to the concentration present at that time. a. Zero order kinetics b. first order kinetics c. elimination half life d. nonlinear kinetics
b. first order kinetics Drug elimination occurs at different rates. Zero-order kinetics yields a constant amount of drug elimination over a specific amount of time. First-order kinetics yields drug elimination that is proportionate to that drugs concentration- at a higher concentration, a larger amount of drug is eliminated within a specific amount of time.
Clearance of a drug in inversely proportional to what (Select 2) a- extration ratio b. half-life. c. blood flow to clearing region. d. concentration in the central compartment.
b. half-life d. concentration in the central compartment. Clearance is the volume of a drug cleared per unit of time. It is inversely proportional to half-life and concentration in the central compartment.
Pathophysiologic considerations for ESRD include: (select 3) a. increased PT b. increased bleeding time c. secondary hyperparathyroidism d. gap metabolic acidosis e. obstructive ventilatory defect f. megaloblastic anemia
b. increased bleeding time c. secondary hyperparathyroidism d. gap metabolic acidosis -uremia increases bleeding time. -gap metabolic acidosis is result of accumulation of non-volatile acids -secondary hyperparathyroidism occurs as a result of impaired active vitamin D3 production & hyperphosphatemia -PT/PTT/PLT count are normal -Erythropoietin production is reduced-contributes to normocytic normochromic anemia. Megaloblastic anemia is a/w NO -fluid overload creates restrictive ventilatory defect
Which conditions increases GFR? a. afferent arteriolar constriction b. increased efferent arteriolar resistance c. increased plasma protein d. Cyclooxygenase inhibition
b. increased efferent arteriolar resistance GF is dependent on RBF & hydrostatic pressure at bowman's capsule -Constriction of efferent arteriole increases hydrostatic pressure & GFR -constriction of afferent arteriole reduces RBF & GFR -Increased plasma protein raises plasm oncotic pressure & reduced GFR -cyclooxygenase inhibition by NSAIDs increases renal vascular resistance & reduces RBF & GFR.
Which statement about therapeutic index is true? a. it is the dose that produces death in 50% of population b. it is calculated by LD 50/ ED50 c. it is a measure of potency d. sevoflurane has a wide therapeutic index
b. it is calculated by LD 50/ ED50
Which factors are associated with a reduction in pseudocholinesterase activity? (select 3) a. obesity b. late stage pregnancy c. Edrophonium d. Esmolol e. Myasthenia gravis f. Metoclopramide
b. late stage pregnancy d. Esmolol f. Metoclopramide -echotiohphate, oral contraceptives, cyclophosphamide, neostigmine -obesity increase activity -MG is a/w resistance to succ
Volatile anesthetic potency is increased by: (select 4) a. red hair b. old age c. hypokalemia d. lithium e. hypothyroidism f. clonidine g. chronic alcohol consumption h. hyponatremia
b. old age d. lithium f. clonidine h. hyponatremia Potency is not affected by hypokalemia & hypothyroidism Potency is decreased by chronic alcohol consumption & red hair
Which drugs inhibit acetylcholinesterase by forming carbamyl esters? (select 2) a. edrophonium b. physostigmine c. echothiophate d. neostigmine
b. physostigmine d. neostigmine edrophonium= electrostatic attachment (competitive inhibition) echothiophate= phosphorylation (non-competitive)
All of the following drugs should be avoided in the patient with acute hepatitis except: a. acetaminophen b. propranolol c. aminodarone d. tetracycline
b. propranolol -non-selective beta blocker that reduces portal pressure by 2 processes: decreased CO (B1) & splanchnic vasoconstriction (B2)
Ketamine: (select 3) a. agonizes the N-methyl-D-aspartate receptor b. relieves somatic pain c. increases risk of depression d. promotes bronchoconstriction e. causes emergence delirium f. increases CMRO2
b. relieves somatic pain e. causes emergence delirium f. increases CMRO2 It is an NMDA antagonist. somatic > visceral pain. Promotes bronchodilation. Is gaining use in treatment of severe depression
Lean body weight is used to calculate the loading dose for: (select 2) a. succinylcholine b. remifentanil c. midazolam d. propofol
b. remifentanil d. propofol
Which of the following is an example of a pharmacodynamic interaction? a. A precepitation of thiopental when it is injected together with succinulcholine into an IV line. b. second gas effect c. Dermerol given to a patient concurrently taking phenelzine. d. cyp450 enzyme induction
b. second gas effect .A pharmacodynamic reaction occurs when one drug impacts or affects the sensitivity of a receptor or tissue to the effects of a second drug. The second gas effect is just such an interaction because administration of nitrous oxide along with a volatile anesthetic agent results in a additive effect by both agents.
Drugs to avoid in pt. on dialysis include: (select 2) a. dexmedetomidine b. vecuronium c. meperidine d. succinylcholine
b. vecuronium c. meperidine drugs that produce active metabolites. -meperidine -> normeperidine which can accumulate & cause convulsions. -Vec-> 3-OH vec. DOA prolonged as a fan of decreased clearance & increased elimination 1/2 life
What percentage of an IV-administered drug remains after 5 half-lives have passed? a. 1% b. 2% c. 3% d. 6%
c. 3% The elimination half-life is the time remains; after a second half-life, 25% of the original dose remains. Therefore, mathematically this is depicted by: 50. After 5 half-lives 96.875% of a drugs original dose and only 3.125% remains.
What is the maximum recommended dose for lidocaine during tumescent anesthesia? a. 5mg/kg b. 7mg/kg c. 55mg/kg d. 75mg/kg
c. 55mg/kg For all other applications max dose is 4.5mg/kg and 7mg/kg when epi added
During the first minute of apnea, the Pacó will rise A. 2 mm Hglmin B. 4 mm Hglmin c. 6 mm Hglmin D. 8 mm Hglmin E. 10 mm Hg/min
c. 6 mm Hglmin During apnea, the PAC02 will increase approximately 6 mm Hg during the first minute and then 3 to 4 mm Hg each minute thereafter (
Anesthetic considerations for AKI (select 2): a. Renal dose dopamine prevents AKI b. Diuretics should be used to convert oliguric to nonoliguric AKI c. Prerenal azotemia can cause acute tubular necrosis d. Hydroxyethyl starches are associated with an increased risk of renal morbidity
c. Prerenal azotemia can cause acute tubular necrosis d. Hydroxyethyl starches are associated with an increased risk of renal morbidity -renal dose dopamine does not prevent nor treat AKI -attempting to convert oliguric to nonoliguric AKI with diuretics increases r/f additional renal injury as well as mortality
Local anesthetics can bind to the voltage-gated sodium channel when it is in the: a. active state only b. resting & inactive states c. active & inactive states d. resting & active states
c. active & inactive states LA preferentially bind to the alpha subunit of the Na channel in the active & inactive states
All of the following are restrictive lung diseases except, a. acute respiratory distress syndrome b. pulmonary edema c. asthma d. interstitial lung disease
c. asthma
Which local anesthetic undergoes the greatest amount of ionization at physiologic pH? a. ropivacaine b. mepivacaine c. chloroprocaine d. lidocaine
c. chloroprocaine
Local anesthetics (select 2): a. increase threshold potential b. decrease resting membrane potential c. have no effect on threshold potential d. have no effect on resting membrane potential
c. have no effect on threshold potential d. have no effect on resting membrane potential When a critical number of Na channels are blocked by LA, Na is unable to enter the neuron in sufficient quantity. This means the neuron can't depolarize & the AP can't be propagated. -Potassium regulates resting membrane potential -Calcium regulates threshold potential
Blood flow is inversely proportional to: a. body temperature b. arteriovenous pressure difference c. hematocrit d. vessel diameter
c. hematocrit Poiseuille's law: flow is directly proportional to vessel radius and the AV pressure difference. Flow is inversely proportional to viscosity & length of the tube Increased temp = decreased viscosity & increased flow Decreased temp= increased viscosity & decreased flow Increased HCT= increased viscosity & decreased flow Decreased HCT= decreased viscosity & increased flow
Select the best induction agent for the patient with pericardial tamponade: a. midazolam b. etomidate c. ketamine d. propofol
c. ketamine Relies upon SNS to maintain BP. Most general anesthetics cause myocardial depression & reduce after load (contribute to CV collapse), LA is the preferred technique for pericardiocentesis If GA, ketamine best option. Activates SNS--increases HR, contractility, and after load. Benzos, etomidate, N2O, and opioids are preferred over volatiles because they produce less myocardial depression & vasodilation. Neuraxial, propofol, and thiopental reduce after load & best avoided
The Meyer-Overton rule states: a. inhaled anesthetic agents interact with stereoselective receptors b. decreased body temperature reduces anesthetic requirements c. lipid solubility is directly proportional to potency d. all anesthetics share a similar mechanism of action, but each may work at a different site.
c. lipid solubility is directly proportional to potency unitary hypothesis states all anesthetics share a similar MOA, but each may work at a different site Modern anesthetic theory suggests that inhalation anesthetics interact with stereoselective receptors Decreased body temp reduces anesthetic requirements, but not meyer overton rule.
Priming the CPB machine with a balanced salt solution reduces all of the following except: a. blood viscosity b. oxygen carrying capacity c. microvascular flow d. plasma drug concentration
c. microvascular flow Produces hemodilution: -decreased HCT, plasma drug [ ], plasma proteins, ó carrying capacity, viscosity -increased microvascular flow
All of the following reduce outflow obstruction in obstructive hypertrophic cardiomyopathy except: a. phenylephrine b. esmolol c. nitroglycerin d. 500ml 0.9% NaCl bolus
c. nitroglycerin HCM is a/w LVOT obstruction 3 determinants of blood flow through the LVOT: 1) Systolic LV volume 2) Force of LV contraction 3) Transmural pressure Things that distend the LVOT are good, things that narrow are bad. NTG reduces preload. This reduces systolic LV volume & causes LVOT to narrow, thereby worsening the obstruction. 500ml bolus would have opposite effect A slower HR extends LV filling time, so esmolol increases systolic LV volume. Additionally, it reduces contractility which helps improve LVOT obstruction. Phenylephrine increases aortic pressure, which increases transmural pressure. This opens LVOT.
What is the most common cause of secondary HTN? a. cigarette smoking b. pregnancy induced HTN c. renal artery stenosis d. coarctation of the aorta
c. renal artery stenosis Likely explanation is that a narrowed renal artery (atherosclerosis or fibromuscular dysplasia) delivers less blood to the affected kidney. In attempt to increase GFR, the kidney activates the RAAS system Definitive tx includes renal artery endarterectomy or nephrectomy. Do NOT give ACEI to a pt. with bilateral renal artery stenosis, as this can significantly reduce GFR & precipitate RF.
During an asthma attack, all of the following are released except: a. histamine b. bradykinin c. secretin d. leukotrienes
c. secretin (Mast cells activity markedly increaes during an asthma attack causing release of chemicals that result in bronchial spasms. Histamine, acetylcholine, leukotrienes.
Which agent has a blood gas coefficient of 0.65? a. N2O b. isoflurane c. sevoflurane d. desflurane
c. sevoflurane
Which of the following physiologic parameters decreases in the obese patient? a. blood volume b. renal clearance c. total body water d. cardiac output
c. total body water
Antidiuretic hormone: a. is produced in the posterior pituitary gland b. increase Na reabsorption in the proximal tubule c. upregulates aquaporin-2 channels d. agonizes the V1 receptor to decrease cAMP
c. upregulates aquaporin-2 channels ADH up regulates aquaporin-2 channels in the collecting ducts. This facilitates H2O reabsorption & restores blood volume & serum osmolarity -ADH is produced in the supraoptic & paraventricular nuclei of the hypothalamus. It is released from the posterior pituitary. -ADH agonizes the V2 receptor (not V1) & increases (not decreases) cAMP -It increases H2O reabsorption in the collecting ducts (not proximal tubule)
Which agent promotes the greatest degree of cardiovascular stability? a. pancuronium b. atracurium c. vecuronium d. succinylcholine
c. vecuronium
For anaphylaxis to occurr: a- Soluble antigens and antibodies must bind to form a insoluble complex. b- Killer T-cells must produce cell-mediated cytotoxic effects. c- IgG and IgM are mediated against antigens on the surface of foreign cells d- Prior exposure is needed for sensitization.
d- Prior exposure is needed for sensitization. The initial exposure to an antigen is a critical step where the immune systems is "made aware" of or sensitized to the offending substance. Upon subsequent exposure, the IgE antibodies form during the initial exposure are "energized" virtually immmediately.
You are anesthetizing an infant with Pierre Robin sequence for mandibular distraction. Which of the following syndromes is MOST likely associated with Pierre Robin sequence? a-Apert b-Crouzon c-Down d-Stickler
d-Stickler Pierre Robin sequence (PRS) is characterized by: 1) Small mandible (micrognathia); 2) Posterior displacement of the tongue (glossoptosis); and, 3) Airway obstruction. It is often, but not always associated with a cleft lip and/or palate. Pierre Robin is called a "sequence" (as opposed to a "syndrome") because everything occurs as a result of mandibular undergrowth in utero. Pierre Robin sequence may occur in isolation, but is often associated with an underlying disorder. The most common syndromes associated with PRS are Stickler syndrome, velocardiofacial syndrome, and Treacher-Collins syndrome. Stickler syndrome is a connective tissue disorder caused by abnormal collagen types II and IX and has autosomal dominant inheritance. It is characterized by "flat" facial appearance with a small nose secondary to midface hypertrophy. Also, extreme myopia and prominent eyes, glaucoma, hearing loss, arthritis, and other problems.
Drugs that bind to the proton pump of gastric parietal cell and inhibit hydrogen ion secretion include: a-ranitidine b-cimetadine c-famotidine d-omeprazole
d-omeprazole Omeprazole (Prilosec) inhibits the proton pump of the parietal cells of the gastric mucosa, decreases hydrogen ion secretion and increase pH. Cimetidine, ranitidine and famotidine also increase gastric pH, however their mechanism is through blockade of the H2 receptor.
Atrial Nautertic peptide increases all of the following except: a-gfr b-sodium excretion c-water excretion d-plasma volume
d-plasma volume ANP is released by the atria in response to atrial distention. If facilitates sodium and water excretion.
What is the normal oxygen delivery in a 70kg adult? a. 250 ml/min b. 15 ml/dL c. 20 ml/dL d. 1000 ml/min
d. 1000 ml/min CaÓ: arterial ó content= 20 ml/Ó/dL DÓ: oxygen delivery= 1000ml/min VÓ: oxygen consumption= 250ml/min CvÓ: venous Ó content= 15 ml/dL
A patient presents to the preoperative clinic with a previous history of infective endocarditis. Which procedure puts the patient at the highest risk of an adverse outcome? a. colonoscopy b. coronary stent placement c. cystoscopy d. dental implant
d. dental implant Patients at risk for endocarditis (valve replacements, complex CHD, previous endocarditis) that are scheduled for dirty procedures a/w transient bacteremia should be receive preoperative antibiotics
Which anesthetic agent produces sedation that most closely resembles natural sleep? a. midazolam b. propofol c. ketamine d. dexmedetomidine
d. dexmedetomidine is an alpha-2 agonist. It produces sedation that most closely resembles natural sleep. -sedation is result of decreased SNS tone & decreased level of arousal -pts. are easily aroused -does not provide reliable amnesia
Clearance is inversely proportional to: a. blood flow to clearing organ b. extraction ratio c. drug dose d. drug [ ] in central compartment
d. drug [ ] in central compartment
The kidney produces: (select 3) a. antidiuretic hormone b. angiotensinogen c. aldosterone d. erythropoietin e. renin f. 1,25 {OH}2 Vitamine D3
d. erythropoietin e. renin f. 1,25{OH}2 Vitamin D3 Renin is produced by the juxtaglomerular apparatus-specifically in the fenestrated epithelium in the afferent arteriole. Erythropoietin is synthesized in the kidney & is secreted in response to hypoxia. Under control of the parathyroid hormone, the kidneys convert inactive vitamins D3 to active vitamins D3 (1,25 {OH}2 vitamins D3) -Angiotensinogen is made in the liver, aldosterone is made in the adrenal cortex, ADH is made in the hypothalamus & released by the posterior pituitary gland
Which anesthetic agent increases the mortality in the patient with Addisonian crisis? a. midazolam b. propofol c. dexmedetomidine d. etomidate
d. etomidate Cortisol & aldosterone synthesis are dependent on enzyme 11-beta-hydroxylase (located in adrenal medulla). Some texts also add 17-alpha-hydroxylase. -Etomidate is known inhibitor of 11-beta-hydroxylase & 17-alpha-hydroxylase. -a single dose of etomidate suppresses adrenocortical function for 5-8 hours (some say 24) -should be avoided in pts. reliant on intrinsic stress response (sepsis or acute adrenal failure). They need all the cortisol they can muster
All of the following reduce the incidence of contrast induced nephropathy EXCEPT: a. fluid bolus 0.9% NaCl b. low-osmolar contrast dye c. sodium bicarbonate d. furosemide
d. furosemide furosemide can reduce IV volume, concentrate radio contrast media inside the kidney & worsen AKI
All of the following can mask the signs of intraoperative hypoglycemia except: a. propranolol b. general anesthesia c. diabetic autonomic neuropathy d. hydrochlorothiazide
d. hydrochlorothiazide (increase glucose)
All of the following are consequences of excess thyroid hormone except: a. diarrhea b. vasodilation c. tremors d. hypoventilation
d. hypoventilation
Which finding is most likely to occur in a patient with CHF? a. decreased natriuretic peptide b. decreased LVEDP c. increased renal blood flow d. increased sympathetic tone
d. increased sympathetic tone Its with CHF rely on elevated levels of circulating catecholamines (increased SNS tone). Anesthetic techniques that interrupt this mechanism can precipitate CV collapse. For example, a standard propofol induction (2mg/kg) is likely to cause issues as it reduces SNS tone while simultaneously reducing myocardial contractility. Ketamine preserves SNS tone, making it a smarter choice in the pt. with CHF. ANP is increased in CHF as result of atrial dilation. ANP causes natriuresis. CHF reduces renal blood flow, & this is primary mechanism that increases RAAS activation.
Identify the most sensitive indicator of recovery from NMB? a. vital capacity >20 ml/kg b. Nerve stimulator shows 4/4 twitches with no fade c. Vt 6ml/kg d. inspiratory force better than -40cmH2O
d. inspiratory force better than -40cmH2O Vt of 6ml/kg= 80% receptors blocked VC > 20ml/kg= 70% receptors blocked 4/4 twitches=70-75% receptors blocked NIF -40cm H2O= 50% receptors blocked
A multimodal approach of postoperative pain management in the patient undergoing Roux-en-Y gastric bypass includes all of the following except: a. dexmedetomidine b. ketamine c. acetaminophen d. ketorolac
d. ketorolac
When compared to propofol, which of the following is unique side effect of fospropofol? a. nausea b. venous irrigation c. bronchospasm d. perineal burning
d. perineal burning
Which statement most accurately describes hepatic perfusion? a. hepatic artery provides 75% of liver blood flow b. protein vein provides 50% of liver blood flow c. hepatic artery provides 75% of liver's oxygen content d. portal vein provides 50% of liver's oxygen content
d. portal vein provides 50% of liver's oxygen content -hepatic artery provides 25% of BF & portal vein 75%; both provide 50% of oxygen content
Which NMBA is most effetely antagonized by sugammadex? a. succinylcholine b. pancuronium c. cisatracurium d. rocuronium
d. rocuronium
Local anesthetics reversibly bind to the alpha subunit of voltage-gated: a. calcium channel b. potassium channel c. magnesium channel d. sodium channel
d. sodium channel
When is awareness most likely to occur during CABG surgery with CPB? a. pre bypass period b. induction of anesthesia c. rewarming d. sternotomy
d. sternotomy d/t surgical stimulation
Which statement best represents the most accurate understanding of acetylcholinesterase inhibitors? a. mixing different agents from the same class yields a synergistic effect b. when compared to adults, neostigmine has a slower onset in infants & children c. the dose should be decreased in patients with renal failure d. there is a ceiling effect above which additional drug fails to produce a better recovery
d. there is a ceiling effect above which additional drug fails to produce a better recovery -mixing is additive -faster in infants -don't have to adjust dose in RF
All of the following enhance renal perfusion except: a.PGÉ b. fenoldopam c. atrial natriuretic peptide d. thromboxane Á
d. thromboxane Á it is a renal vasoconstrictor. its production is increased during renal ischemia
All of the following muscles dilate the upper airway except: a. tensor palatine b. hyoid muscles c. genioglossus d. thyroarytenoid
d. thyroarytenoid -tensor palatine (opens nasopharynx) -genioglossus (open oropharynx) -hyoid muscles (opens hypopharynx)
What is the most sensitive sign of anastomotic leak following gastric bypass? a. abdominal pain b. shoulder pain c. fever d. unexplained tachycardia
d. unexplained tachycardia
Compared to atropine, glycopyrrolate is more likely to cause: a. tachycardia b. sedation c. mydriasis d. xerostomia
d. xerostomia (dry mouth) quaternary ammonium- does not cross BBB atropine is tertiary ammonium- crosses BBB- sedation & mydriasis; a/w more tachycardia
The action of which of the following agents is antagonized by the prior or concomitant administration of epidurally administered 2-chloroprocaine? I. Fentanyl 2. Bupivacaine 3. Morphine 4. BUlOrphanol
(1,2,3) 2-Chloroprocaine administered epidurally appears to decrease the quality and duration of subsequently administered fentanyl, morphine, and bupivacaine. The exact mechanism is unclear but does not seem to be related to the acid pH of chloroprocaine (because neutralization with bicarbonate has similar antagonistic properties). Butorphanol (a K-receptor agonist) does not appear to be antagonized)
Inhalation anesthetics that produce uterine relaxation include :(Choose all the best answers). 1. Halothane 2. Isoflurane 3. Sevofturane 4. Nitrous oxide
(1,2,3) All halogenated anesthetic agents (halothane, enflurane, isoflurane, desflurane, sevoflurane) cause a dose-related relaxation of uterine smooth muscle. With anesthetic concentrations of 0.2 MAC the decrease in uterine activity is slight, and these agents have been used for inhalation analgesia during labor. At 0.5 MAC, uterine relaxation is more significant but the uterine response to oxytocin remains intact. Nitrous oxide does not interfere with uterine activity.
Factors that lead to an increased response to inhaled anesthetics during pregnancy include : 1. Increased minute ventilation 2. Decreased functional residual capacity 3. Decreased MAC 4. Increased cardiac output
(1,2,3) An increased minute ventilation hastens the entry of inhalation drugs into the lung and hastens the uptake of the more soluble inhalation agents. The decrease in functional residual capacity increases the uptake of the more insoluble inhalation agents. MAC during pregnancy decreases 25% to 40% in animal studies so that absorbed drug has increased effect. An increase in cardiac output leads to a slower induction of inhalation agent because the concentration of anesthetic agent reaching the brain is lower.
Untoward effects associated with magnesium overdose include :(Choose all the best answers). 1. Heart block 2. Respiratory depression 3. Hypotension 4. Coagulopathy
(1,2,3) As the blood level of magnesium increases, different adverse reactions can be seen. At 10 mEq/L, deep tendon reflexes are lost. At 15 mEq/L, sinoatrial and atrioventricular block, as well as respiratory paralysis, can occur. At 25 mEq/L, cardiac arrest can develop. Magnesium sulfate does not cause coagulopathy; however, a coagulopathy may develop in patients with pregnancyinduced hypertension (who may be simultaneously receiving MgS04.
True statements regarding pregnant diabetic patients include which of the following? :(Choose all the best answers). 1. Incidence of cesarean section is higher in diabetics 2. Insulin requirements increase during pregnancy 3. Preeclampsia is more common in diabetics 4. Insulin readily crosses the placenta
(1,2,3) Diabetes mellitus is the most common endocrine problem associated with pregnancy. Type I diabetes mellitus (due to a decrease in insulin secretion) occurs in one of every 700 to 1000 gestations. Gestational diabetes, which occurs only during pregnancy, is seen in about 2% to 5% of all pregnancies. Although substantial advances in the obstetric and anesthetic management of diabetic parturients has been made, maternal and fetal mortality are still higher in these patients than in parturients without diabetes. One important goal of insulin therapy in these patients is to avoid both hyperglycemia and hypoglycemia. In general, insulin requirements are increased during pregnancy from 0.7 unitslkg/day at 2 weeks of gestation to 0.8 unitslkg/day at 18 weeks and 0.9 to 1.0 unitslkg/day at 32 weeks and more of gestation. Insulin does not readily cross the placenta and therefore does not have any direct effects on glucose metabolism in the fetus. Glucose, however, readily crosses the placenta. Preeclampsia and large-for-gestational-age fetuses occur more frequently in parturients with diabetes. Because of fetal macrosomia, cesarean section is more common in diabetics than nondiabetics.
True statements regarding MgS04 therapy for preeclampsia include which of the following?:(Choose all the best answers). 1. Serum magnesium levels can be estimated by changes in deep tendon reflexes 2. Excessive serum magnesium levels cause motor weakness 3. The therapeutic range for serum magnesium is 4 to 7 mEq/L 4. The antidote for magnesium toxicity is neostigmine 700
(1,2,3) Magnesium sulfate is the anticonvulsant of choice in the preeclamptic patient in North America and is more effective than phenytoin. In addition to its anticonvulsant effect, MgSO 4 exerts a peripheral effect at the neuromuscular junction. The therapeutic range for serum MgS04 is 4 to 7 mEq/L. Loss of deep tendon reflexes occurs at 10 mEq/L, respiratory arrest at 15 mEq/L, and cardiac arrest at greater than 25 mEq/L. The treatment for magnesium toxicity is calcium
Which of the following antihypertensive drugs used to treat pregnancy-induced hypertension by virtue of smooth muscle relaxation is(are) capable of causing increased postpartum hemorrhage? (Choose all the best answers). 1. Nitroprusside 2. Nifedipine 3. Nitroglycerin 4. LabetaIol
(1,2,3) Nitroprusside, nifedipine, and nitroglycerin have direct effects on smooth muscle (such as the uterus) and may be associated with increased postpartum hemorrhage. Nitroprusside and nitroglycerin's effects are short lived after the drug is discontinued. Labetalol (adrenergic blocker) does not affect uterine contractions significantly
Signs and symptoms of a postdural puncture headache may include::(Choose all the best answers). 1. Exacerbation by sitting or standing 2. Nausea and vomiting 3. Relief by recumbency 4. Fever
(1,2,3) Postdural puncture headaches are positional headaches (exacerbated by sitting or standing and relieved with recumbency). They are bilateral and typically located in the fronto-occipital regions. They are sometimes associated with tinnitus, deafness, photophobia, and diplopia (sixth cranial nerve palsy). Nausea and vomiting have been recorded in some studies in more than 20% of patients. Seizures, lethargy, fever, nuchal rigidity, and unilateral location suggest other headache etiologies
Preeclampsia is designated as "severe preeclampsia" if anyone of the following conditions exists? (Choose all the best answers). I. Proteinuria greater than 5 g/24 hours 2. Visual disturbances 3. Urine output less than 400 mL/24 hours 4. White blood cell count greater than 15,000
(1,2,3) Preeclampsia occurs in about 7% of all pregnancies and is associated with hypertension, proteinuria, and/or generalized edema. It usually occurs after the 24th week of gestation but may present earlier in cases of gestational trophoblastic disease (e.g., molar pregnancy). It is classified as either mild or severe. It becomes severe if any of the following conditions coexist: systolic blood pressure ~ 160; diastolic blood pressure .~ 110; proteinuria >5 g/24 hr; urine output <400 mL/24 hr; eNS disturbances (seizures, altered consciousness, headaches, visual disturbances); pulmonary edema; epigastric or right upper quadrant pain; hepatic rupture; impaired liver function; thrombocytopenia; or HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets). Most patients have increased cardiac output, normal or increased systemic vascular resistance, and normal or decreased blood volumes and filling pressures. The white blood count is not part of the diagnosis of preeclampsia. In fact, the white blood count progressively rises during normal pregnancy from 6000/mm3 to 9000 to II ,000/mm3• During labor the white blood count increases to 13,000/mm3 and rises to an average of 15,000/mm3 on the first postpartum day
Appropriate maneuvers for prevention of aortocaval compression include: 1. Manual displacement of the uterus to the left 2. Placing a wedge under the patient's left side 3. Placing a wedge under the patient's right side 4. Placement of the patient is Trendelenburg position
(1,2,3) Prevention of aortocaval compression is done after 18 to 20 weeks of gestation (when the uterus is large enough to press on the vena cava and aorta). It consists of left uterine displacement performed manually by placing a wedge under the patient's right side or by rotating the OR table to the left. In about 10% of women, right uterine displacement (wedge under left side) is more effective than left uterine displacement. Trendelenburg position without uterine displacement may worsen the condition because it shifts the uterus further back on the great vessels
Agents that are useful for decreasing the incidence of shivering during labor in which epidural analgesia is used include: (Choose all the best answers). 1. Administration of epidural fentanyl. 2. Warming of IV fluids. 3. Administration of epidural meperidine. 4. Warming the epidural anesthetic solutions to body temperature.
(1,2,3) Shivering occurs in 10% of all normal deliveries. ,The frequency increases to 20% to 70% of patients r,eceiving epidural or spinal anesthesia for labor or cesarean deliveries. Use of sufentanil (50 J-Lg), fentanyl (100 J-Lg), or meperidine (25 mg) and warming the IV fluid can help decrease the incidence of shivering. It is postulated that the efficacy of meperidine may reside in its properties as both a J-L- and a K-receptor agonist within the spinal cord. Warming the epidural anesthesia solution to body temperature has no effect.
A decrease in uterine blood flow can occur with: 1. Aortocaval compression 2. Uterine contractions 3. Drug-induced hypotension 4. Local anesthetics in high concentrations
(1,2,3,4) A decrease in uterine blood flow may result from a decrease in uterine artery pressure (aortocaval compression, hemorrhage, drug-induced hypotension, hypotension during sympathetic blockade), an increase in uterine venous pressure (uterine contractions, vena cava obstruction), an increase in uterine vascular tone (catecholamines), and by local anesthetics in high concentrations.
The following drugs and dosages used in newborn resuscitation include:(Choose all the best answers). 1. Epinephrine, 0.1 to 0.3 mL/kg of 1: 10,000 solution 2. Normal saline, 10 mL/kg 3. Sodium bicarbonate, 2 mEq/kg 4. Naloxone, 0.1 mglkg
(1,2,3,4) All listed drugs and dosages are correct. Epinephrine and naloxone are given rapidly. Sodium bicarbonate is given slowly, no faster than I mEq/kg/min and only after adequate ventilation is provided. Volume expanders (O-negative blood, normal saline, or Ringer's lactate) are usually given over 5 to 10 minutes. Drugs used in newborn resuscitation that can be given down the endotracheal tube include Oxygen, Naloxone, and Epinephrine (ONE)
Adverse effects associated with aortocaval compression by the gravid uterus include : 1. Nausea and vomiting 2. Pallor 3. Changes in cerebration 4. Decreases in uterine blood flow
(1,2,3,4) Aortocaval compression can occur in up to 15% of pregnant patients at tenn. Compression of the vena cava reduces venous return, producing symptoms of hypotension, nausea and vomiting, pallor, and changes in cerebration. Compression of the aorta decreases uterine blood flow.
Addition of epinephrine (5 ug/mL) to the following local anesthetic(s) administered epidurally will reduce the peak maternal local anesthetic concentration by 30% to 50%. 1. Lidocaine 2. Etidocaine 3. Mepivacaine 4. Bupivacaine
(1,3) Epinephrine, in a dose of 5 ug/mL (1 :200,000), reduces the peak blood levels of some local anesthetics such as lidocaine and mepivacaine but not others such as etidocaine and bupivacaine. The different effects may be related to the higher lipid solubility of etidocaine and bupivacaine, which results in a greater uptake by the adipose tissue
Possible causes of late decelerations during fetal heart monitoring include :(Choose all the best answers). 1. Aortocaval compression 2. Umbilical cord compression 3. Increased uterine tone 4. Fetal head compression
(1,3) Late decelerations are due to uteroplacental insufficiency and can result whenever uterine blood flow decreases.
Appropriate agents for aspiration prophylaxis in parturients who are to be anesthetized for an emergency surgical procedure include(Choose all the best answers). 1. Metoclopramide 2. Ranitidine 3. Sodium citrate 4. Mylanta
(1,3) Nonparticulate antacids (sodium citrate) and particulate antacids (e.g., Maalox, Mylanta) both raise gastric pH rapidly and can help neutralize gastric pH. However, if particulate antacids are aspirated, significant pulmonary damage may result whereas nonparticulate antacids are relatively benign. H2-receptor antagonists (cimetidine or ranitidine) raise gastric pH but take time (greater than 30 minutes) to exert their effect. Metoclopramide helps increase gastric emptying (in as little as 15 minutes) but also increases lower esophageal sphincter tone and may help decrease the chance of aspiration
Which of the following decrease(s) FHR beat-to-beat variability? :(Choose all the best answers). 1. Isoflurane 2. Ephedrine 3. Fetal asphyxia 4. Glycopyrrolate
(1,3) Some baseline FHR beat-to-beat variability is ,normal and reflects the normal adjustments by the sympathetic and parasympathetic nervous systems. A decrease in variability is seen with CNS depressants such as barbiturates, general anesthetics, and fetal asphyxia. Atropine, which crosses the placenta, can decrease variability and raise the FHR. Glycopyrrolate, because it does not cross the placenta, has no effect on variability. Ephedrine has been shown to increase FHR beatto-beat variability.
During an emergency cesarean section under spinal anesthesia the parturient develops cough, wheezing, stridor, and becomes cyanotic. The trachea is intubated and food is noted in the pharynx. Appropriate treatment in this patient should consist of ::(Choose all the best answers). 1. Tracheal suctioning 2. Steroids 3. 100% oxygen and positive end-expiratory pressure (PEEP) 4. Saline lavage
(1,3). Three different aspiration syndromes have been described: aspiration of particulate matter, aspiration of acid fluid, and aspiration of fecal material. Aspiration of fecal material can occur with bowel obstruction and rarely is a problem in obstetrics. Symptoms of aspiration include coughing, tachypnea, tachycardia, bronchospasm, and hypoxemia. Treatment is supportive and includes suctioning the airway, administration of increased concentration of oxygen, and application of PEEP as needed. Use of saline lavage will not remove acid from the airway and can worsen hypoxemia. Steroids have not been effective in limiting the inflammation that occurs and may increase the risk of secondary bacterial infection.
Statements that correctly describe differences between fetal and maternal blood include which of the following?(Choose all the best answers). I. Fetal blood has a lower hemoglobin concentration than does maternal blood 2. Fetal hemoglobin has a greater affinity for Ó than does maternal hemoglobin 3. The fetal oxyhemoglobin dissociation curve is shifted to the right of the maternal oxyhemoglobin dissociation curve 4. Fetal blood has a lower pH than does maternal blood
(2,4) The fetus has several compensatory mechanisms for dealing with low 02 pressures (umbilical vein P02 approximately equal to 30 mm Hg) to which it is exposed. These include a higher hemoglobin concentration (15 to 20 g/dL) and the presence of fetal hemoglobin, which has a greater affinity for oxygen (the oxyhemoglobin dissociation curve is shifted to the left of adult hemoglobin) than maternal hemoglobin. Fetal blood has a lower pH than maternal blood, which may be related to the higher Pacó 1evels.
During the second stage of labor, complete pain relief can be obtained with:(Choose all the best answers). 1. Paracervical block 2. Spinal block 3. Pudendal nerve block 4. Lumbar epidural block
(2,4) The first stage of labor starts with the onset of labor and ends with complete cervical dilation (10 cm). It is associated with uterine contractions and dilation of the cervix and is transmitted via the autonomic nervous system through the sympathetic fibers that pass through the paracervical region and enter the eNS at TIO-LI segments. The second stage of labor includes these pathways and adds the somatic fibers of the birth canal that are transmitted via the pudendal nerve entering the eNS at S2-4. Spinal and epidural anesthesia can cover both areas and can produce complete anesthesia during the second stage of labor. If a low spinal or saddle block is performed (covering only sacral areas), the uterine contraction pain will still be felt. Paracervical blocks only block the first stage pain. Pudendal blocks block the somatic component during the second stage but not visceral pain of contractions.
Antacid premedication in the parturient should be carried out with :(Choose all the best answers). 1. Aluminum hydroxide 2. Magnesium trisilicate 3. Magnesium hydroxide 4. Sodium citrate
(4) All of the choices listed are antacids; however, clear nonparticulate antacids (0.3 M sodium citrate) are preferred over particulate antacids (aluminum hydroxide, magnesium trisilicate, magnesium hydroxide) because the clear nonparticulate antacids cause less pulmonary damage if aspirated. Sodium citrate 30 mL neutralizes 255 mL of Hel with a pH of 1.0. Neutralization of gastric acid occurs rapidly (Le., <5 minutes) and will last up to an hour .
Turbulent gas flow through a tube increases 1. Linearly with the pressure gradient down the tube 2. Linearly with the density of the gas 3. To the fourth power of the radius of the tube 4. Approximately to the square of the radius of the tube
(4) Approximately to the square of the radius of the tube. The Hagan-Poiseuille Law of Friction does not apply when gas flow through a tube is turbulent. Turbulent gas flow increases approximately with the square of the radius of the tube (instead of the radius raised to the fourth power), the square root of the pressure gradient down the tube, and the reciprocal of gas density (instead of gas viscosity)
The rationale for inserting the epidural needle into the epidural space with the cutting edges parallel to the dural fibers during placement of a labor epidural is::(Choose all the best answers). 1. It reduces the incidence of cannulation of a dural vein with the epidural catheter 2. It reduces the incidence of dural puncture (wet tap) 3. It reduces the incidence of accidental subdural cannulation with the epidural catheter 4. It reduces the incidence of postdural puncture headache if puncture of the dura inadvertently occur.
(4) Postdural puncture headaches are less common in patients after dural puncture when the bevel of the epidural needle is oriented parallel to the long axis of the vertebral canal as compared to perpendicular placement. One must, however, rotate the epidural needle 90 degrees before catheter insertion to obtain a midline placement of the catheter. (Some believe that the rotation could increase the incidence of dural punctures, whereas others do not.) The other factors listed in this question are not related to epidural needle bevel placement relative to the dural.
Agents useful for raising the gastric pH just before induction of general anesthesia for emergency cesarean section include :(Choose all the best answers). 1. Cimetidine 2. Metoclopramide 3. Ranitidine 4. Sodium citrate
(4) Sodium citrate is the only drug listed that will raise gastric pH quickly. Cimetidine and ranitidine are H2-receptor antagonists that will increase gastric pH but take at least 30 minutes to work. Metoclopramide is not an antacid but may be useful by increasing the lower esophageal sphincter tone
Variable decelerations may occur in response to :(Choose all the best answers). 1. Fetal head compression 2. Uteroplacental insufficiency 3. Maternal hypotension 4. Umbilical cord compression
(4,) There are several periodic FHR patterns. Accelerations in FHR in response to fetal movement signify fetal well-being. Early decelerations are decreases in FHR usually less than 20 beats/min and occur concomitantly with uterine contractions. Typically they are smooth and are mirror images of the uterine contractions. They are not associated with fetal compromise and are caused by head compression, which produces a vagal slowing of the FHR. Late decelerations are decreases in FHR that occur 10 to 30 seconds after the onset of a contraction and end 10 to 30 seconds after the end of a contraction. They are due to uteroplacental insufficiency and can result whenever uterine blood flow decreases. The delayed onset is due to the time required to sense a low oxygen tension. The decrease in FHR may be a vagal reflex (mild cases) or due to direct myocardial depression from hypoxia (severe cases). Typically, in severe cases beat-to-beat variability is decreased or absent as well. Variable decelerations are decreases in FHR that vary in shape, depth, and duration from contraction to contraction. They are thought to be due to transient umbilical cord compression. A sinusoidal pattern is a regular smooth wavelike pattern with no short-term variability. It may be caused by severe fetal anemia or result from the maternal administration of narcotics.
Each of the following treatmenls might be useful in restoring a prolonged prothrombin time (PT) to the normal range EXCEPT A. Recombinant factor VllI B. Vitamin K C. Fresh frozen plasma D. Stopping warfarin (Coumadin) E. Cryoprecipitate
(A) The PT and the activated partial thromboplastin time (aPTI) are common tests used to evaluate coagulation factors. The PT primarily tests for factor VII in the extrinsic pathway, as weil as factors I, U, V, and X of the common pathway. The aPTI primarily tests for factors VIII and IX of the intrinsic pathway, as well as factors I, II, V, and X of the common pathway. Although the PT is prolonged with deficient function of factors I, II , V, VII, or X, it is more sensitive to deficiencies of factor VII and less so with deficiencies of factor I or ll. In fact, the PT is not prolonged until the level of fibrinogen (factor I) is less than 100 mg/dL and may only be prolonged 2 seconds when the level of factor 11 (prOlhrombin) is 10% of normal. Factors II, VII , lX, and X are vitamin-K-dependent factors and their formation is blocked with Coumadin therapy. Administering factor VUI wiil not help a prolonged PT.
A 65-year-old patient with moderate aortic stenosis develops a sudden increase in heart rate during an appendectomy under general anesthesia. The ventricular rate is 190 beats/min and is irregularly irregular, arterial blood pressure is 70/45 mm Hg, and there is 2-mm ST-segment depression in lead V 5 of the ECG. Which of the following would be the most appropriate treatment for myocardial ischemia in this patient? A. Electrical cardioversion B. Esmolol C. Nitroglycerin D. Verapamil E. Phenylephrine
(A) The classic signs and symptoms of aortic stenosis (angina, syncope, and congestive heart failure) are related primarily to an increase in left ventricular systolic pressure, which is necessary to maintain forward stroke volume. These elevated pressures cause concentric left ventricular hypertrophy. With severe disease, the left ventricular chamber becomes dilated and myocardial contractility diminishes. The primary goals in the anesthetic management of such patients undergoing noncardiac surgery are to maintain normal sinus rhythm and avoid prolonged alterations in heart rate (especially tachycardia), systemic vascular resistance, and intravascular fluid volume. Supraventricular tachycardia should be terminated promptly by electrical cardioversion in this patient because of concomitant hypotension and myocardial ischemia.
Which of the following represents the greatest risk factor for allergic reaction to protamine after cessation of cardiopulmonary bypass? A. Diabetes treated with NPH insulin B. History of hemophilia C. History of cold agglutinins D. Previous vasectomy E. Allergy to fish
(A) \Allergic reactions have been described in patients who have been chronically exposed to low doses of protamine or to any molecule similar to protamine. Such reactions have been described most often in patients treated with protamine containing preparations of insulin. Protamine should be avoided in patients with a history of a previous anaphylactic reaction to protamine. This presents a special problem for patients who require cardiopulmonary bypass. Heparin reversal in these patients can be carried out with the drug hexadimethrine or reversal can be omitted entirely. If heparin reversal is omitted, however, several hours may be required until adequate hemostasis can be achieved, which may lead to a substantial blood loss and multiple transfusion
For which severity of aortic stenosis is spinal anesthesia contraindicated? (A) 0.5-1.0 cm 2 (B) 1.0-1.5 cm 2 (C) 1.5-2.5 cm 2 (D) 2.5-3.5 cm 2
(A) 0.5-1.0 cm 2 An aortic valve area o 0.7 cm2 is associated with sudden death. In general, neuraxial anesthesia is used cautiously with spinal anesthesia being relatively contraindicated due to the sympathectomyinduced drop in SVR
Epidural morphine was administered for postoperative pain control. What is the duration of action? (A) 12-24 hours (B) 4-6 hours (C) 24-48 hours (D) 2-6 hours
(A) 12-24 hours The duration of action for sufentanil 4-6 hours; and fentanyl 2-6 hours.
What ultrasound frequency is used when placing an epidural or spinal? (A) 2-5 MHz (B) 5-10 MHz (C) 10-15 MHz (D) 20-25 MHz
(A) 2-5 MHz The ultrasound probe for peripheral nerve blocks utilizes high frequency. Lower frequency ultrasound probes are used or spinal and epidural placement.
How many liters o CÓ per 100 g of absorbent can soda lime absorb? (A) 23 L (B) 32 L (C) 44 L (D) 18 L
(A) 23 L Soda lime is the more common absorbent and is capable of absorbing up to 23 L of CÓ per 100 g of absorbent.
In a normal person, what percentage of the cardiac output is dependent on the "atrial kick"? A. 25 B. 35 C. 45 D. 55 E. 65
(A) 25 In a normal heart, approximately 20% to 30% of the cardiac output is produced by the "atrial kick." In pathologic conditions, such as aortic stenosis, the "atrial kick" may contribute more substantially to cardiac output
What is resting cerebral oxygen consumption? (A) 3.5 mL/100g/min (B) 5 mL/100g/min (C) 100 mL/min (D) 250 mL/min
(A) 3.5 mL/100g/min Resting cerebral oxygen demand averages 3.5 mL/100g/min.
What is the onset of analgesia following administration of epidural morphine 5 mg? (A) 30-60 minutes (B) 15-30 minutes (C) 5-15 minutes (D) >60 minutes
(A) 30-60 minutes The onset of epidural morphine is 30 to 60 minutes. The duration of analgesia is 12 to 24 hours. Larger doses o epidural morphine are needed for analgesia. However, delayed respiratory depression may result.
What is the approximate cylinder pressure delivered to the anesthesia machine? (A) 45 psi (B) 50 psi (C) 1,900 psi (D) 745 psi
(A) 45 psi Rationale: The approximate cylinder pressure delivered to the anesthesia machine is 45 psi; 50 psi is pipeline pressure; 1,900 psi is the approximate psi or a full Ó E-cylinder; and 745 is the psi for N2O E-cylinder.
A 2-year-old child is anesthetized for resection of a posterior fossa tumor. Preoperatively, the patient is lethargic and disoriented. Which of the following is most likely to adversely alter ICP? A. 5% dextrose in water B. Normal saline C. Lactated Ringer's solution D. 5% albumin E. Fresh frozen plasma
(A) 5% dextrose in water Five percent dextrose in water (D5 W) is contraindicated in neurosurgical patients with intracranial hypertension for two reasons. First, D5 W easily passes through the blood-brain barrier. Once in the brain tissue, glucose is rapidly metabolized, leaving only free water, which causes cerebral edema. Second, hyperglycemia is associated with increased severity of neurologic damage in patients with cerebral ischemia. This is thought to result from increased lactate production during anaerobic glycolysis during the period of ischemia.
How many liters does an oxygen E-cylinder tank hold? (A) 660 L (B) 1,590 L (C) 625 L (D) 750
(A) 660 L B is nitrous oxide; C is air.
What patient is least likely to experience a postdural puncture headache? (A) 70-year-old male (B) 40-year-old male (C) 20-year-old female (D) 60-year-old female
(A) 70-year-old male Risk factors linked to post dural puncture headache include age, gender, needle size, and pregnancy. Young females represent the highest risk population. The incidence of PDPH in females is greater than males. The incidence o PDPH is greater in younger versus older populations
Calculate the ideal body weight (IBW) for a 6 feet, 90-kg male. (A) 80 kg (B) 177 kg (C) 72 kg (D) 145 kg
(A) 80 kg The IBW or males is calculated by the following equation: 105 lb + 6 lb or every inch over 5 eet. For emales, add 5 lb or every inch over 5 eet.
Kinking or occlusion of the transfer tubing from the patient breathing circuit to the closed scavenging system interface can result in A. Barotrauma B. Hypoventilation C. Hypoxia D. Hyperventilation E. None of the above
(A) A scavenging system with a closed interface is one in which there is communication with the atmosphere through positive- and negative-pressure relief valves. The positive-pressure relief valve will prevent transmission of excessive pressure buildup to the patient breathing circuit, even if there is an obstruction distal to the interface or if the system is not connected to wall suction. However, obstruction of the transfer tubing from the patient breathing circuit to the scavenging circuit is proximal to the interface. This will isolate the patient breathing circuit from the positivepressure relief valve of the scavenging system interface. Should this occur, barotrauma to the patient's lungs can result.
Which statement is true of Aδ fibers? (A) A δ fibers are myelinated, synapse in Rexed laminae I and V, and transmit primarily mechanical or thermal pain. (B) A δ fibers are unmyelinated, synapse in Rexed laminae II and VII, and transmit primarily mechanical or thermal pain. (C) A δ fibers are myelinated, synapse in Rexed laminae III and X, and transmit primarily mechanical or thermal pain. (D) A δ ibers are unmyelinated, synapse in Rexed laminae IV and VI, and transmit primarily mechanical or thermal pain.
(A) A δ fibers are myelinated, synapse in Rexed laminae I and V, and transmit primarily mechanical or thermal pain. Aδ bers are myelinated, terminate in laminae I and V, and respond to mechanical and thermal stimuli.
Which of the following does not relieve pain by decreasing inflammation? (A) Acetaminophen (B) Ketorolac (C) Ibuprofen (D) Celecoxib
(A) Acetaminophen Acetaminophen does not exert an antiinflammatory effect.
Preoperative treatment of subarachnoid hemorrhage patients, without concomitant cerebral vasospasm, might include any of the following EXCEPT: A. Induced hypertension (to 20% above baseline) B. Administration of nimodipine C. Sedation D. Analgesic therapy E. Administration of anti epileptic drugs
(A) After subarachnoid hemorrhage, patients may experience rebleeding, cerebral vasospasm, intracranial hypertension, and seizures. Provided the patient is not experiencing cerebral vasospasm, hypertension should be avoided. In contrast, had this patient been in vasospasm, induced hypertension would have been an appropriate therapeutic intervention (also see explanation to question 776). Hypertension is avoided, in part, by the administration of sedative and analgesic medications. Antiepileptic drugs and calcium channel blockers (e.g., nimodipine) often are administered in an attempt to prevent or mitigate seizures and the sequelae of cerebral vasospasm, respectively.
During postanesthesia recovery the patient is snoring and use of the accessory muscle for ventilation are noted. What is the most likely cause? (A) Airway obstruction (B) Hypoventilation (C) Hypoxemia (D) Bronchospasm
(A) Airway obstruction Airway obstruction may contribute to hypoventilation. Other signs and symptoms of hypoventilation include: decreased respiratory rate or tachypnea with shallow respirations. In the PACU, hypoventilation is the primary cause of hypoxemia resulting in varied signs and symptoms. Airway symptoms including wheezing, secretions, tachypnea, and accessory muscle use are prominent signs.
Which of the following is the most sensitive indicator or lert ventricular myocardial ischemia? A. Wall-motion abnormalities on the echo-cardiogram B. ST-segment changes in lead V, of the electrocardiogram (ECG) c. Appearance of V waves on the pulmonary capillary wedge pressure tracing D. Elevation of the pulmonary capillary wedge pressure E. Decrease in cardiac output as measured by the thermo-dilution technique.
(A) All of the choices listed in this question occur during myocardial ischemia. However, of the choices listed, presence of left ventricular wall-motion abnormalities is the most sensitive indicator .
All of the following would result in less trace gas pollution of the O.R atmosphere EXCEPT A. Using a high gas flow in a circular system B. Tight mask seal during mask induction C. Use of a scavenging system D. Periodic maintenance of the anesthesia machine E. Allow patient to breath 100% Ó as long as possible before extubation.
(A) Although controversial, chronic exposure to low concentrations of volatile anesthetics may constitute a health hazard to OR personnel. Therefore, removal of trace concentrations of volatile anesthetic gases from the OR atmosphere with a scavenging system and steps to reduce and control gas leakage into the environment are required. High-pressure system leakage of volatile anesthetic gases into the OR atmosphere occurs when gas escapes from compressed-gas cylinders attached to the anesthetic machine (e.g., faulty yokes) or from tubing delivering these gases to the anesthesia machine from a central supply source. The most common cause of low-pressure leakage of anesthetic gases into the OR atmosphere is the escape of gases from sites located between the flow meters of the anesthesia machine and the patient, such as a poor mask seal. The use of high gas flows in a circle system will not reduce trace gas contamination of the OR atmosphere. In fact, this could contribute to the contamination if there is a leak in the circle system.
Hypothyroidism and hyperthyroidism could occur in patients receiving which of the following antidysrhythmic drugs? A. Amiodarone B. Verapamil C. Phenytoin D. Lidocaine E. Procainamide
(A) Amiodarone is a benzofurane derivative with a chemical structure similar to that of thyroxine, which accounts for its ability to cause either hypothyroidism or hyperthyroidism. Altered thyroid function occurs in 2% to 4% of patients when amiodarone is administered over a long period. Amiodarone prolongs the duration of the action potential of both atrial and ventricular muscle without altering the resting membrane potential. This accounts for its ability to depress sinoatrial and atrioventricular node function. Thus amiodarone is effective pharmacologic therapy for both recurrent supraventricular and ventricular tachydysrhythmias. In patients with Wolff-Parkinson-White syndrome, amiodarone increases the refractory period of the accessory pathway. Atropine-resistant bradycardia and hypotension may occur during general anesthesia because of the significant anti-adrenergic effect of amiodarone. Should this occur, isoproterenol should be administered or a temporary artificial cardiac pacemaker should be inserted.
The patient is scheduled for a thyroidectomy. What are your primary anesthetic concerns? Select (3) three (A) Arrhythmias (B) Tachycardia (C) Body temperature (D) Hypotension (E) Corneal abrasion
(A) Arrhythmias (B) Tachycardia (C) Body temperature Each of the options should concern the anesthetist when caring for a hyperthyroid patient. However, the primary concern focuses on decreasing sympathetic stimulation that leads to cardiac arrhythmias, hypertension, tachycardia, and increased body temperature. Corneal abrasion is possible in the patient with exophthalmos. Hypotension may result rom chronic hypovolemia.
Select the FALSE statement regarding noninvasive arterial blood pressure monitoring devices. A. If the width of the blood pressure cuff is too narrow, the measured blood pressure will be falsely lowered B. The width of the blood pressure cuff should be 40% of the circumference of the patient's arm. C. If the blood pressure cuff is wrapped around the arm too loosely, the measured blood pressure will be falsely elevated. D. Oscillometric blood pressure measurements are accurate in neonates. E. Frequent cycling of automated blood pressure monitoring devices can result in edema distal to the cuff.
(A) Automated noninvasive blood pressure (ANIBP) devices provide consistent and reliable arterial blood pressure measurements. Variations in the cuff pressure resulting from arterial pulsations during cuff deflation are sensed by the device and are used to calculate mean arterial pressure. Then, values for systolic and diastolic pressures are derived from formulas that use the rate of change of the arterial pressure pulsations and the mean arterial pressure (oscillometric principle). This methodology provides accurate measurements of arterial blood pressure in neonates, infants, children, and adults. The main advantage of ANIBP devices is that they free the anesthesia provider to perform other duties required for optimal anesthesia care. In addition, these devices provide alarm systems to draw attention to extreme blood pressure values and have the capacity to transfer data to automated trending devices or recorders. Improper use of these devices can lead to erroneous measurements and complications. The width of the blood pressure cuff should be approximately 40% of the circumference of the patient's arm. If the width of the blood pressure cuff is too narrow or if the blood pressure cuff is wrapped too loosely around the arm, the blood pressure measurement by the device will be falsely elevated. Frequent blood pressure measurements can result in edema of the extremity distal to the cuff. For this reason, cycling of these devices should not be more frequent than every 1 to 3 minutes. Other complications associated with improper use of ANIBP devices include ulnar nerve paresthesia, superficial thrombophlebitis, and compartment syndrome. Fortunately, these complications are rare occurrence.
Which of the following pharmacologic agents decreases uterine contraction in a dose-dependent fashion? A. Barbiturates B. Diazepam C. Ketamine D. Nitrous oxide E. Local anesthetics
(A) Barbiturates cause a dose-dependent reduction in uterine contractions. Diazepam and nitrous oxide have no effect. Ketamine produces a dose-related oxytocic effect on uterine tone during the second trimester of pregnancy but no increase in tone at term. Local anesthetics injected intravenously cause an increase in uterine tone and at high levels can lead to tetanic contractions
Select the TRUE statement concerning administration of glucose-containing solutions to the patient with a closed head injury versus a patient with a spinal cord injury. A. Glucose-containing solutions are contraindicated in both patient groups B. Glucose-containing solutions are contraindicated in patients with closed head injury but acceptable in patients with spinal cord injuries C. Glucose-containing solutions are acceptable in patients with closed head injuries but contraindicated in patients with spinal cord injuries D. Glucose-containing solutions may be given to either patient group if blood glucose concentrations do not exceed 200 mg/dL E. Glucose-containing solutions are acceptable in both patient groups
(A) Both laboratory and clinical studies have reported that hyperglycemia at the time of either focal (e.g., stroke) or global (e.g., systemic shock or cardiac arrest) ischemia results in a worsening of neurologic outcome (Le., both histologic and functional). Unfortunately, it is not widely appreciated that the administration of glucose does not need to produce high blood glucose levels to augment postischemic cerebral injury. Thus, glucose-containing solutions should not be administered to patients who are at risk for either cerebral or spinal cord injury
Referred pain from the diaphragm can be expected in which dermatome? (A) C4 (B) C7 (C) T4 (D) T7
(A) C4 Diaphragmatic innervation originates in cervical levels 3, 4, and 5.
What is the innervation of the brachial plexus? (A) C5-C8 and T1 (B) C4-C8 (C) C4-C8 and T1 (D) C5-C7 and T1- 2
(A) C5-C8 and T1 The C4 and T2 innervation is minimal or absent.
A decrease in Pacó of 10 mm Hg will result in A. A decrease in serum potassium concentration ([K+]) of 0.5 mEq/L B. A decrease in [K+] of 1.0 mEq/L C. No change in [K+] under normal circumstances D. An increase in [K+] of 0.5 mEq/L E. An increase in [K+] of 1.0 mEq/L
(A) Cardiac dysrhythmias are a common complication associated with acid-base abnormalities. The etiology of these dysrhytbmias is related partly to the effects of pH on myocardial potassium homeostasis. As a general rule, there is an inverse relationship between [K+] and pH. For every 0.08 unit change in pH there is a reciprocal change in [K+] of approximately 0.5 mEqlL
A 60-year-old female with mitral stenosis has the following post induction vital signs: HR 125, BP 70/45 followed by sudden supraventricular tachycardia (SV ). What will you do first? (A) Cardioversion (B) Ephedrine (C) Phenylephrine (D) Vasopressin
(A) Cardioversion Marked hemodynamic deterioration in a patient with mitral stenosis rom sudden SV is cause for immediate cardioversion.
A morbidly obese male patient is scheduled for a bariatric surgery. Which of the following diagnostic tests should be ordered? Select (3) three (A) Chest X-ray (B) 12-lead EKG (C) Coagulation studies (D) HCG (E) Glucose tolerance test
(A) Chest X-ray (B) 12-lead EKG (C) Coagulation studies Diagnostic testing for bariatric surgery includes a CBC, complete chemistry, fasting blood glucose, lipid profile, iron, vitamin, and mineral levels. Chest X-ray, 12-lead EKG, and coagulation testing is indicated. Te pregnancy test is not indicated.
If 2-chloroprocaine is accidentally injected into maternal blood, it will be rapidly hydrolyzed by pseudocholinesterase. In a patient who is homozygous for atypical cholinesterase, the half-life for this drug in the blood would be expected to be: A. Approximately 2 minutes B. Approximately 5 minutes C. Approximately 15 minutes D. Approximately 30 minutes E. Greater than 1 hour
(A) Chloroprocaine breaks down rapidly in the blood by normal pseudocholinesterase. In vitro plasma half-life is 21 seconds in maternal blood and 43 seconds in fetal blood. In patients who are homozygous for the atypical cholinesterase, the half-life is prolonged to about 2 minutes.
What nerve injury results most often with the lithotomy position? (A) Common peroneal (B) Sciatic (C) Obturator D) Saphenous
(A) Common peroneal Each of the nerves may be affected by the lithotomy position. The nerve most likely to be injured in the lithotomy position is the common peroneal.
What factor does not influence the spread of local anesthetic placed in the epidural space? (A) Concentration (B) Dose (C) Site of injection (D) Age
(A) Concentration The dose and site of injection influence the spread of local anesthetic. The density of the block is influenced by the concentration of local anesthetic. With advanced age, the dose of local anesthetic decreases due to anatomical changes. Additional factors that influence the spread of local anesthetic in the epidural space are pregnancy, weight, height, rate of injection, and patient position.
A patient taking furosemide is scheduled for a total knee arthroscopy. What statement is true? (A) Continue in patients with chronic renal failure. (B) Discontinue. (C) Continue in patients with diabetes. (D) Discontinue in the elderly.
(A) Continue in patients with chronic renal failure. Diuretics may be held without concern except for patients with chronic renal failure for congestive heart failure.
A spinal anesthetic is planned for an obese patient. How will you adjust the dose of local anesthetic? (A) Decrease 20%. (B) Increase 20%. (C) Decrease 10%. (D) Increase 10%.
(A) Decrease 20%. The dose of local anesthetic used for spinal or epidural anesthesia in obese patients is decreased 20-25%.
During an unremarkable spinal anesthetic a bilateral 2 level in a healthy parturient results in a cardiac arrest. Which of the following is most likely responsible? (A) Decreased preload (B) Effect of local anesthetic on the medulla (C) Blockade of the carotid sinus (D) Cardiogenic hypertensive chemoreflex
(A) Decreased preload Cardiac arrest occurs in approximately 0.07-0.15% of spinal anesthetics. Most of these episodes of cardiac arrests are due directly or indirectly to sympathetic blockade. Inhibiting sympathetic e erents decreases venous return with reduction in right atrial pressure by 36% with low spinals and 53% with high spinals. Volume depletion can increase this to 66% on average. Dramatic reduction in preload initiate three re exes which can result in bradycardia or sinus arrest: (1) T e pacemaker stretch re ex is a result o myocardial pacemaker cells ring in proportion to the degree o stretch. Decreased venous return results in decreased stretch and thus decreased ring. (2) Low pressure baroreceptors are stimulated in the right atrium and vena cava which causes bradycardia. (3) T e Bezold-Jarisch re ex occurs when intracardiac mechanoreceptors in the left ventricle are stimulated producing bradycardia.
The anesthetic plan includes an inhalational induction. Which inhalational agent is the least desirable or a patient with chronic bronchitis and a 50-pack-year history of smoking? (A) Desflurane (B) Sevoflurane (C) Halothane (D) Nitrous oxide
(A) Desflurane Irritation of the airway is common with desflurane and iso urane. These inhalational agents are pungent. Less pungency exists with nitrous oxide, sevo urane, halothane, and there ore, less airway irritation.
Physiologic factors in the mother that lead to an increase in oxygen delivery to the uterus include: 1. Increased minute ventilation 2. Hemoglobin P50 of 30 3. Increased cardiac output 4. Increased hematocrit
(A) Despite a decrease in maternal hematocrit, oxygen delivery to the uterus is increased by several mechanisms during normal pregnancies. An increase in cardiac output, as well as vasodilation of uterine blood vessels, increases blood flow to the uterus. An increase in minute ventilation not only lowers the Pacó to 30 to 32 mm Hg but also raises the Páo to about 103 mm Hg. In addition, the oxyhemoglobin dissociation curve is shifted to the right (P 50 from 27 to 30 mm Hg)
Which of the following rate control agents should be avoided in patients undergoing general anesthesia with acute onset wide-complex supraventricular tachycardia (SV )? (A) Digitalis (B) Adenosine (C) Esmolol (D) Amiodarone
(A) Digitalis The SV is of an unknown type. If a reentrant pathway is present blocking the AV node with digoxin may in act exacerbate tachycardia while limiting other treatment options (or adenosine).
What is the most common cause of non surgical bleeding following massive blood transfusion? (A) Dilutional thrombocytopenia (B) Citrate toxicity (C) Dilution of factors V and X (D) Dilution of factors II and VIII
(A) Dilutional thrombocytopenia Dilutional thrombocytopenia is the most common cause of non surgical bleeding following massive blood transfusion. Dilutional coagulopathy is also associated with massive transfusion, specifically dilution of factors V and VIII.
Which portion of the spinal cord is most associated with transmission of pain signals? (A) Dorsal horn (B) Central canal (C) Ventral horn (D) Pia mate
(A) Dorsal horn The proximal portion of pain receptors terminate in the dorsal horn.
A patient is scheduled for bariatric surgery. What is the recommended induction dose for propofol? (A) Dose based on lean body weight (B) Dose based on total body weight (C) Decrease dose by 30% (D) Decrease dose by 10%
(A) Dose based on lean body weight The induction dose of propofol for an obese patient is based on the lean body weight (LBW). A maintenance dose o propofol is based on the total body weight.
Which of the following are considered symptomatic of fat embolism following a long bone fracture? Select (3) three (A) Dyspnea (B) Confusion (C) Petechiae (D) Decreased free fatty acids (E) One week post fracture
(A) Dyspnea (B) Confusion (C) Petechiae Signs of fat embolism following a long bone fracture generally occur within 72 hours of the event. Increased free fatty acids lead to capillary-alveolar membrane disturbance. Neurological symptoms result due to cerebral circulation damage and edema.
Which statement about fresh frozen plasma (FFP) administration is correct? Select (2) two (A) Each unit of FFP will increase the level of each clotting factor by 2-3% in adults. (B) The initial therapeutic dose is 10-15 mL/kg. (C) It should be ABO-compatible. (D) It must be Rh-compatible. (E) The therapeutic goal is to achieve 80% of the normal coagulation factor concentration.
(A) Each unit of FFP will increase the level of each clotting factor by 2-3% in adults. (B) The initial therapeutic dose is 10-15 mL/kg. A unit of FFP will increase the level of each clotting actor by 2-3% in adults. he initial therapeutic dose is generally 10-15 mL/kg and should be ABO-compatible. Rh compatibility is not mandatory. The therapeutic goal is to achieve 30% of the normal coagulation factor concentration.
While observing the fetal heart monitor during labor you note a decrease in the fetal heart rate. What is the probable cause? (A) Epidural opioids (B) terbutaline (C) Ritodrine (D) Atropine
(A) Epidural opioids Fetal tachycardia is linked to beta- adrenergic agonists (ritodrine, terbutaline), atropine and epinephrine. Epidural or intrathecal analgesia contributes to lowering the fetal heart rate particularly with repeated dosing.
A patient with ischemic cardiomyopathy, with a preoperative ejection fraction of 15%, presents for a general anesthetic. After induction of general anesthesia, the vital signs include a blood pressure of 79/61 mmHg and a heart rate of 54 beats per minute. What intravenous drip is best? (A) Epinephrine (B) Vasopressin (C) Phenylephrine (D) Milrinone
(A) Epinephrine The most effective treatment would be to restore the circulating catecholamine levels through an epinephrine or norepinephrine drip, restoring an adequate blood pressure and cardiac output. Increasing afterload without simultaneously increasing contractility (with phenylephrine or vasopressin), may raise blood pressure for a time but decrease cardiac output and increase left-ventricular end-diastolic, thereby dangerously decreasing coronary perfusion in a patient already suffering from coronary ischemia. Milrinone will indeed increase cardiac output, but will only further decrease blood pressure by exacerbating vasodilation, thereby decreasing perfusion pressure to vital organs including the heart.
The primary mechanism by which the action of tetracaine is terminated when used for spinal anesthesia is: A. Systemic absorption B. Uptake into neurons C. Hydrolysis by pseudocholinesterase D. Hydrolysis by nonspecific esterases E. Spontaneous degradation at 37°C
(A) Ester local anesthetics are hydrolyzed by cholinesterase enzymes that are present mainly in plasma and in a smaller amount in liver. Because there is no cholinesterase enzymes present in cerebrospinal fluid (CSF), the anesthetic effect of tetracaine will persist until it is absorbed into systemic circulation. The rate of hydrolysis varies, with chloroprocaine being fastest, procaine intermediate, and tetracaine the slowest. Toxicity is inversely related to the rate of hydrolysis; tetracaine is, therefore, the most toxic.
What is the minimum quantity of intracardiac air that can be detected by a precordial Doppler? A. 0.25 mL B. 5.O mL C. 10 mL D. 25 mL E. 50 mL
(A) Except for the transesophageal echocardiograph, the Doppler ultrasound is the most sensitive device for detection of intracardiac air. Under ideal circumstances, as little as 0.25 mL of intracardiac air can be detected by this device
Which narcotic does not cause histamine release? (A) Fentanyl (B) Morphine (C) Hydromorphone (D) Meperidine
(A) Fentany Lowered systemic vascular resistance results rom bolus doses of morphine, hydromorphone and meperidine. Fentanyl administration may result in vagus mediated bradycardia.
Which narcotic does not cause histamine release? (A) Fentanyl (B) Morphine (C) Hydromorphone (D) Meperidine
(A) Fentanyl Lowered systemic vascular resistance results rom bolus doses o morphine, hydromorphone and meperidine. Fentanyl administration may result in vagus mediated bradycardia.
How will the symptoms of an acute hemolytic transfusion reaction manifest in a patient under general anesthesia? (A) Fever, unexplained tachycardia, hypotension and diffuse oozing in surgical field. (B) Nausea, fever, flank pain, unexplained tachycardia, and hypotension. (C) Hemoglobinuria, chest and flank pain, fever, and hypotension. (D) Hypertension, unexplained tachycardia, fever, erythema, and hives.
(A) Fever, unexplained tachycardia, hypotension and diffuse oozing in surgical field. Unlike the symptoms of acute hemolytic reaction in awake patients (chills, nausea, ever, chest pain, and flank pain), in anesthetized patients, these symptoms are masked. Symptoms include fever, unexplained tachycardia, hypotension, hemoglobinuria, and diffuse oozing in the surgical eld.
A 2-year-old child is anesthetized for resection of a posterior fossa tumor. Preoperatively, the patient is lethargic and disoriented. Which of the following is most likely to adversely alter ICP? A. 5% dextrose in water B. Normal saline C. Lactated Ringer's solution D. 5% albumin E. Fresh frozen plasma
(A) Five percent dextrose in water (D5 W) is contraindicated in neurosurgical patients with intracranial hypertension for two reasons. First, D5 W easily passes through the blood-brain barrier. Once in the brain tissue, glucose is rapidly metabolized, leaving only free water, which causes cerebral edema. Second, hyperglycemia is associated with increased severity of neurologic damage in patients with cerebral ischemia. This is thought to result from increased lactate production during anaerobic glycolysis during the period of ischemia.
Which anticholinergic cannot cross the blood-brain barrier? (A) Glycopyrrolate (B) Atropine (C) Scopolamine (D) Scopolamine and atropine
(A) Glycopyrrolate Tertiary amines atropine and scopolamine easily cross the blood-brain barrier. Quaternary amines (glycopyrrolate) are unable to cross the blood-brain barrier.
Which inhalational agent is a halogenated alkane? (A) Halothane (B) Nitrous oxide (C) Desflurane (D) Sevoflurane
(A) Halothane Nitrous oxide is an inorganic anesthetic gas. Desflurane and sevoflurane are halogenated with fluorine.
Which drugs are known triggers or malignant hyperthermia? Select (3) three (A) Halothane (B) Sevoflurane (C) Methohexital (D) Sodium thiopental (E) Succinylcholine
(A) Halothane (B) Sevoflurane (E) Succinylcholine All inhalation general anesthetics and depolarizing muscle relaxants trigger malignant hyperthermia. Barbiturates are considered sa e anesthetic agents.
Where is the primary location of hepatic microsomal enzymes? (A) Hepatic smooth endoplasmic reticulum (B) Kidneys (C) Gastrointestinal system (D) Small intestine
(A) Hepatic smooth endoplasmic reticulum The primary location of hepatic microsomal enzyme activity is the hepatic smooth endoplasmic reticulum. Microsomal enzymes are also located in the kidneys and gastrointestinal system to a lesser extent. The majority of reactions in the small intestine involve P450 enzymes.
Following administration of intrathecal anesthesia for cesarean section, the patient is unable to speak, loses consciousness, and is hypotensive. What is the most likely cause? (A) High spinal (B) Use of ropivacaine (C) Spinal hematoma (D) Use of bupivacaine
(A) High spinal Hypotension is a common side effect of intrathecal anesthesia. Causative factors for high spinals include lack of adjustment in dosages for pregnant patients as well as excessive spread of the local anesthetic. For cesarean section, a T4 level is desired. All local anesthetics may produce a high spinal. Spinal hematoma produces symptoms including severe back and leg pain and motor weakness.
Which variable increases Minimum Alveolar Concentration (MAC)? (A) Hypernatremia (B) Hyperthermia (C) Acute intoxication (D) Ketamine
(A) Hypernatremia Hyperthermia, acute intoxication, and ketamine decrease MAC. Hypernatremia increases MAC.
How does an opioid inhibit postsynaptic nociceptive signal transmission? Select (2) two (A) Hyperpolarization (B) Excitation (C) Opening calcium channels (D) Opening potassium channels
(A) Hyperpolarization (D) Opening potassium channels Opioids impede postsynaptic signal transmission by opening potassium channels resulting in hyperpolarization
Which complications are most concerning following carotid endarterectomy? Select (2) two (A) Hypertension (B) Hypoxemia (C) Hypotension (D) Delayed emergence
(A) Hypertension (B) Hypoxemia Each of the complications poses challenges following carotid endarterectomy. Denervation o the carotid baroreceptor blunts the feedback loop in response to hypertension, thus postoperative hypertension is possible with carotid endarterectomy. The carotid baroreceptor is instrumental in respiratory stimulation in the presence of hypoxemia. For a patient dependent on the hypoxic drive for ventilation (i.e., COPD or narcotic use), unchecked hypoxemia may develop.
What causes hypocalcemia? Select (3) three (A) Hypoparathyroidism (B) Paget's disease (C) Fat embolism (D) Rapid infusion of 1,000 mL albumin (E) Biliary colic (F) Chronic immobilization
(A) Hypoparathyroidism (C) Fat embolism (D) Rapid infusion of 1,000 mL albumin Low PH levels, at embolism, and rapid infusion of large volumes of blood preservative with citrate ions (including albumin) cause hypocalcemia.
A healthy 59-year-old (60-kg) woman with a normal preoperative ECG develops wide complex tachycardia under general anesthesia for breast biopsy. Blood pressure is 81/47 mm Hg and heart rate is 220 beats/min. The most appropriate therapy would be A. Electrical cardioversion B. Administration of lidocaine, 60 mg IV C. Administration of procainamide, 20 mg/min IV D. Administration of amiodarone, 300 mg IV E. Adenosine, 6 mg IV
(A) Hypotension in the presence of wide complex tachycardia is a medical emergency and requires immediate treatment. A synchronized DC countershock should be carried out immediately. Lidocaine or amiodarone could be administered after sinus rhythm is reestablished
Which of the following symptoms is consistent with cardiac tamponade? (A) Hypotension, tachycardia, tachypnea, muffled heart sounds, and pulsus paradoxus (B) Hypertension, tachycardia, tachypnea, and widened pulse pressure (C) Jugular venous distension, mu led heart sounds, and bradycardia (D) Hypotension, widened pulse pressure, and tachycardia
(A) Hypotension, tachycardia, tachypnea, muffled heart sounds, and pulsus paradoxus With cardiac tamponade, acute hypotension, tachycardia, and tachypnea develop. The heart's ability to relax is impaired by fluid compressing it; thus, diastolic pressures equalize across the heart resulting in decreased stroke volume and decreased cardiac output. Cardiac output thus becomes heart rate dependent, thus tachycardia. Decreased cardiac output and elevated left atrial and pulmonary artery pressures lead to tachypnea. Furthermore, with respiratory effort the fluctuations in venous return have a marked change on the diastolic pressures within the heart. A marked pulsus paradoxus develops or the very preload-dependent heart. Heart sounds are muffled.
Which group lists the Vitamin K-dependent clotting actors? (A) II, VII, IX, X (B) II, IV, IX, XII (C) III, VII, X, XI (D) I, VII, IX, XI
(A) II, VII, IX, X Which group lists the Vitamin K-dependent clotting actors? (A) II, VII, IX, X (B) II, IV, IX, XII (C) III, VII, X, XI (D) I, VII, IX, XI Rationale: Vitamin K-dependent factors include factors II, VII, IX, and X. T ey require vitamin K or completion o their synthesis in the liver. In the absence of vitamin K, these 4 clotting actors are produced in normal amounts but are non functional.
When do symptoms of ischemic optic neuropathy that result in postoperative vision loss typically occur? (A) Immediately postoperatively (B) 2 hours postoperatively (C) 2 days postoperatively (D) 2 weeks postoperatively
(A) Immediately postoperatively Symptoms typically start following emergence from anesthesia, but may occur up to 12 days following surgery.
When do symptoms of ischemic optic neuropathy that result in postoperative vision loss typically occur? (A) Immediately postoperatively (B) 2 hours postoperatively (C) 2 days postoperatively (D) 2 weeks postoperatively
(A) Immediately postoperatively Symptoms typically start following emergence from anesthesia, but may occur up to 12 days following surgery.
Which of the following may be harmful when in proximity to the Magnetic Resonance Imaging (MRI) machine? Select (3) three (A) Implanted medication pumps (B) Pacing wires (C) Cardiac pacemakers (D) Pulse oximeter (E) Precordial stethoscope
(A) Implanted medication pumps (B) Pacing wires (C) Cardiac pacemakers Items containing iron ( ferromagnetic) are strongly attracted to the MRI magnet. MRI Compatible equipment lists items that are acceptable for use for patients undergoing MRI.
General anesthesia is administered to an otherwise healthy 38-year-old patient undergoing repair of a right inguinal hernia. During mechanical ventilation, the anesthesiologist notices that the scavenging system reservoir bag is distended during inspiration. The most likely cause of this is A. An incompetent pressure-relief valve in the mechanical ventilator B. An incompetent pressure-relief valve in the patient breathing circuit C. An incompetent inspiratory unidirectional valve in the patient breathing circuit D. An incompetent expiratory unidirectional valve in the patient breathing circuit E. None of the above; the scavenging system reservoir bag is supposed to distend during inspiration
(A) In a closed scavenging system interface, the reservoir bag should expand during expiration and contract during inspiration. During the inspiratory phase of mechanical ventilation the ventilator pressure-relief valve closes, thereby directing the gas inside the ventilator bellows into the patient breathing circuit. If the ventilator pressure-relief valve is incompetent, there will be a direct communication between the patient breathing circuit and scavenging circuit. This would result in delivery of part of the mechanical ventilator VT directly to the scavenging circuit, causing the reservoir bag to inflate during the inspiratory phase of the ventilator cycle
In a normal person, what percentage of the cardiac output is dependent on the "atrial kick"? A. 25 B. 35 C. 45 D. 55 E. 65
(A) In a normal heart, approximately 20% to 30% of the cardiac output is produced by the "atrial kick." In pathologic conditions, such as aortic stenosis, the "atrial kick" may contribute more substantially to cardiac output.
Which of the following physiological effects result from acute pain stimulation? Select (3) three (A) Increased myocardial workload (B) Decreased vital capacity (C) Decreased gastric emptying (D) Decreased platelet aggregation (E) Increased intestinal motility
(A) Increased myocardial workload (B) Decreased vital capacity (C) Decreased gastric emptying The physiological effects of pain include increased platelet aggregation leading to thrombosis as well as decreased intestinal motility with the potential for paralytic ileus.
Which mechanisms of action are common among nonsteroidal anti-in ammatory drugs? Select (2) two (A) Inhibition of cyclooxygenase (B) Inhibition of prostaglandin synthesis (C) Inhibition of lipoxygenase (D) Inhibition of leukotriene synthesis
(A) Inhibition of cyclooxygenase (B) Inhibition of prostaglandin synthesis Nonsteroidal anti-in ammatory drugs inhibit cyclooxygenase and subsequent prostaglandin synthesis.
You administered meperidine IV. Immediately following administration the patient developed profound hypotension, hyperpyrexia, and respiratory arrest. What drug interaction do you suspect? (A) Interaction with monoamine oxidase inhibitors (MAOs) (B) Interaction with erythromycin (C) Interaction with sodium pentothal (D) Interaction with etomidate
(A) Interaction with monoamine oxidase inhibitors (MAOs) Patients receiving MAO inhibitors should not receive meperidine. In addition to hypotension, hypertension, hyperpyrexia, and respiratory arrest, coma may result. Interaction o alfentanil and
A 24-year-old patient is brought to the intensive care unit· after sustaining a closed head injury in a motor vehicle accident. Each of the following would be useful in managing intracranial hypertension in this patient EXCEPT A. Corticosteroids B. Barbiturates C. Hyperventilation D. Osmotic diuresis E. Placement of the patient in the head up position.
(A) Intracranial pressure (ICP) is determined by the relationship between the intracranial vault (formed by the skull), volume of brain parenchyma, volume of CSF, and CBV. Studies evaluating the effectiveness of corticosteroids in the setting of head injury, or global or focal brain ischemia, have demonstrated either no improvement or a worsening of neurologic outcome (also see explanation to question 726). All intravenous anesthetics, except ketamine, cause some degree of reduction in CMR, CBF, CBV, and ICP (provided ventilation is not depressed). Of intravenous anesthetics, barbiturates are thought to be the "gold standard" for anesthetic-mediated brain protective therapy during focal or incomplete global brain ischemia. The impact of hyperventilation on ICP is discussed in question 763. Both osmotic and loop diuretics are effective in reducing ICP. Elevation of the head above the level of the heart facilitates effluent of blood from the calvarium, which results in decreases in CBV and ICP.
A 54-year-old patient is undergoing a three-vessel coronary artery bypass graft under general anesthesia. After induction, the pulmonary capillary wedge pressure is 15 mm Hg and pulmonary artery pressures are 26/13 mm Hg. Suddenly, new 30-mm Hg V waves appear on the monitor screen. Systemic blood pressure is 120/70 mm Hg, heart rate is 75 beats/min, and pulmonary artery pressure is 50/35 mm Hg. Which of the following drugs should be administered to the patient? A. Nitroglycerin B. Nitroprusside C. Esmolol D. Phenylephrine E. Dobutamine
(A) Ischemia of the posterior wall of the left ventricle and posterior leaflet of the mitral valve can cause prolapse of the posterior leaflet and retrograde blood flow into the left atrium during systole. This can be manifested as V (ventricular) waves on the pulmonary capillary wedge pressure tracing even before ST-segment depression can be seen on the ECG.
What effect does cerebral ischemia have on CBF autoregulation? A. CBF autoregulation is ablated B. CBF autoregulation is ablated at low cerebral perfusion pressures but remains intact at high cerebral perfusion pressures. C. CBF autoregulation is ablated at high cerebral perfusion pressures but remains intact at low cerebral perfusion pressures. D. The CBF autoregulatory curve is shifted to the right. E. The CBF autoregulatory curve is shifted to the left.
(A) It is important to note that CBF autoregulation is easily impaired and modified by numerous factors, such as cerebral vasodilators (including volatile anesthetics), chronic hypertension, and cerebral ischemia. Cerebral ischemia abolishes CBF autoregulation such that CBF becomes passively dependent on the cerebral perfusion pressure.
Where is Tuffer's line located? (A) L4 (B) L2 (C) L1 (D) L3
(A) L4 Tuffer's line is located just above the iliac crests crossing the L4-5 vertebrae.
Which solution is appropriate for replacement of calculated fluid deficits, blood loss, or third-space loss in the pediatric patient? (A) Lactated Ringer's solution (B) 5% dextrose in water (C) 5% dextrose in 0.45% normal saline (D) 25% albumin
(A) Lactated Ringer's solution Lactated Ringer's is a common and appropriate choice or volume replacement.
What are the primary adductors o the vocal cords? (A) Lateral cricoarytenoid muscles (B) Recurrent laryngeal nerve ( C) Posterior cricoarytenoid muscles (D) External laryngeal nerve
(A) Lateral cricoarytenoid muscles The primary abductors of the vocal cords are the posterior cricoarytenoid muscles. The recurrent laryngeal nerve innervates the muscles of the larynx. The external laryngeal nerve innervates the cricothyroid muscle.
Which nerve provides sensory innervation to the lateral thigh? (A) Lateral femoral cutaneous (B) Saphenous (C) Femoral (D) Posterior femoral cutaneous
(A) Lateral femoral cutaneous The saphenous nerve provides innervation below the knee. The femoral nerve and its branches innervate the anterior thigh, hip, medial leg, and ankle. The posterior femoral cutaneous nerve innervates the posterior thigh.
Which actors contribute to the rapid development of hypoxia during apnea in neonates? Select (2) two (A) Low functional residual capacity (B) Low basal metabolic rate (C) High oxygen reserve (D) High oxygen demand
(A) Low functional residual capacity (D) High oxygen demand Neonates and infants have relatively low functional residual capacity coupled with relatively increased oxygen demand.
Which Mapleson circuit is the most efficient or controlled ventilation? (A) Mapleson D (B) Mapleson A (C) Mapleson B (D) Mapleson C
(A) Mapleson D Because resh gas ow orces alveolar air away rom the patient and toward the APL valve, the Mapleson D circuit is the most ef cient or controlled ventilation.
Which narcotic analgesic is not used for patient controlled analgesia (PCA)? (A) Meperidine (B) Morphine (C) Fentanyl (D) Hydromorphone
(A) Meperidine The demerol metabolite normeperidine is neurotoxic; therefore, it is not recommended for PCA.
The patient is shivering in the post-anesthesia care unit. Which intravenous medication will you use? (A) Meperidine 10 to 25 mg (B) Fentanyl 25 µg (C) Morphine 5 mg (D) Hyromorphone 5 mg
(A) Meperidine 10 to 25 mg Compared to other narcotics, meperidine 10 to 25 mg IV decreases shivering in postoperative patients
Which of the following acid-base disturbances is the least well compensated? A. Metabolic alkalosis B. Respiratory alkalosis C. Increased anion gap metabolic acidosis D. Normal anion gap metabolic acidosis E. Respiratory acidosis
(A) Metabolic alkalosis. The degree to which a person can hypoventilate to compensate for metabolic alkalosis is limited; hence, this is the least well-compensated acid-based disturbance. Respiratory compensation for metabolic alkalosis is rarely more than 75% complete. Hypoventilation to a Pacó greater than 55 mm Hg is the maximum respiratory compensation for metabolic alkalosis. A Pacó greater than 55 nun Hg most likely reflects concomitant respiratory acidosis.
In which valvular disease is the pulmonary capillary wedge pressure (PCWP) an overestimation of the left ventricular end-diastolic pressure (LVEDP)? (A) Mitral stenosis (B) Mitral regurgitation (C) Aortic stenosis (D) Aortic regurgitation
(A) Mitral stenosis Because of the abnormal transvalvular gradient in mitral stenosis, the PCWP overestimates the LVEDP.
Which of the following are absolute contraindications for electroconvulsive therapy (ECT )? Select (3) three (A) Myocardial infarction <6 weeks (B) Pheochromocytoma (C) Glaucoma (D) Pregnancy (E) Cerebrovascular accident <3 months
(A) Myocardial infarction <6 weeks (B) Pheochromocytoma (E) Cerebrovascular accident <3 months Glaucoma and pregnancy are relative contraindications to EC . Other relative contraindications include cardiac dysfunction (angina, CHF), bone fractures, thrombophlebitis, retinal detachment, and pulmonary disease. Absolute contraindications also include intracranial mass and/or surgery, and cervical spine instability.
According to NIOSH regulations, the highest concentration of volatile anesthetic contamination allowed in the OR atmosphere when administered in conjunction with N20 is A. 0.5 ppm B. 2 ppm C. 5 ppm D. 25 ppm E. 50 ppm
(A) NIOSH mandates that the highest trace concentration of volatile anesthetic contamination of the OR atmosphere when administered in conjunction with N20 is 0.5 ppm.
Tachycardia, euphoria, delirium, and excitement are noted when conducting the preoperative evaluation in the emergency department. Which of the following is probably not related to the symptoms? (A) Narcotics (B) Cocaine (C) Hallucinogens (D) Marijuana
(A) Narcotics Opioids produce respiratory depression, hypotension, and bradycardia. Euphoria may occur as well as pinpoint pupils linked to overdose
A 54-year-old patient is undergoing a three-vessel coronary artery bypass graft under general anesthesia. After induction, the pulmonary capillary wedge pressure is 15 mm Hg and pulmonary artery pressures are 26/13 mm Hg. Suddenly, new 30-mm Hg V waves appear on the monitor screen. Systemic blood pressure is 120/70 mm Hg, heart rate is 75 beats/min, and pulmonary artery pressure is 50/35 mm Hg. Which of the following drugs should be administered to the patient? A. Nitroglycerin B. Nitroprusside C. Esmolol D. Phenylephrine E. Dobutamine
(A) Nitroglycerin Ischemia of the posterior wall of the left ventricle and posterior leaflet of the mitral valve can cause prolapse of the posterior leaflet and retrograde blood flow into the left atrium during systole. This can be manifested as V (ventricular) waves on the pulmonary capillary wedge pressure tracing even before ST-segment depression can be seen on the ECG
The patient is scheduled for a total knee arthroscopy under general anesthesia. The patient's history includes retina surgery using sulfur hexafluoride 2 months ago. What will you avoid? (A) Nitrous oxide (B) Rocuronium (C) Sevoflurane (D) Fentanyl
(A) Nitrous oxide Nitrous oxide expands the gas bubble and may cause intraocular hypertension. There are no other medication contraindications.
Which of the following is true regarding a transplanted heart? (A) No response to atropine (B) No response to isoproterenol (C) No response to milrinone (D) No response to epinephrine
(A) No response to atropine A transplanted heart does not have autonomic innervation and thus is devoid of vagal influence. Therefore a vagolytic medication such as atropine or glycopyrrolate will have no effect on heart heart. Isoproterenol and epinephrine are the medications of choice to increase heart rate. Milrinone, a phosphodiesterase inhibitor, directly increase intracellular cAMP apart rom any neuron-mediated or catecholamine-mediated process and thus will be an e ective inotrope.
A patient is scheduled for knee arthroscopy. The blood glucose is elevated along with the A1c. What will you do first? (A) Notify the surgeon that the surgery will be delayed. (B) Proceed with the surgery. (C) Cancel the surgery. (D) Call the endocrinologist
(A) Notify the surgeon that the surgery will be delayed. The elective case may be rescheduled or placed on the schedule later in the day. An insulin infusion may be needed to lower the blood sugar closer to normal limits. An endocrine consult is in order following surgery.
Which medications should be held on the day of surgery? Select (2) two (A) Oral hypoglycemic agents (B) tricyclic antidepressants (C) Selective serotonin reuptake inhibitors (D) Beta-adrenergic blockers (E) Angiotensin-converting enzyme (ACE) inhibitors
(A) Oral hypoglycemic agents (C) Selective serotonin reuptake inhibitors Stopping tricyclic antidepressants may lead to cholinergic symptoms, cardiac disturbances, and neurological symptoms. Stopping ACE inhibitors may result in atrial fibrillation and/or congestive heart failure. If beta-adrenergic blockers are held, cardiac disturbances, and withdrawal symptoms may occur.
What is the only piece of equipment that will ensure that oxygen is present in the pipelines or cylinder? (A) Oxygen analyzer (B) Hypoxic guard (C) Oxygen fail-safe device (D) Cylinder gauge
(A) Oxygen analyzer Inspired oxygen analysis is the only method of ensuring the presence of oxygen in the pipeline or cylinder.
The "a" wave on the central venous pressure tracing corresponds to which on the EKG tracing? (A) P wave (B) QRS wave (C) QT interval (D) T wave
(A) P wave The a-wave on the venous tracing corresponds to atrial contraction. The P-wave corresponds to atrial depolarization couple to atrial contraction.
Which of the following statements concerning the distribution of Ó and CÓ in the upright lungs is true? A. PA02 is greater at the apex than at the base B. PAC02 is greater at the apex than at the base C. Both PA02 and PAC02 are greater at the apex than at the base D. Both PA02 and PAC02 are greater at the base than at the apex E. PAC02 is equal throughout the lung.
(A) PA02 is greater at the apex than at the base. Also see explanation to question 132. The ventilation/perfusion ratio is greater at the apex of the lungs than at the base of the lungs. Thus, dependent regions of the lungs are hypoxic and hypercarbic compared to the nondependent region.
Somatic pain associated with the second stage of labor can be controlled by any of the following regional nerve blocks EXCEPT A. Paracervical block B. Saddle block C. Lumbar epidural D. Pudendal block E. Caudal
(A) Pain during the first stage of labor is visceral and is related to uterine contractions and dilation of the cervix. Pain impulses enter the spinal cord at T10-LI level. Pain in the second stage includes the visceral pain of the first stage but adds the somatic pain created with pelvic floor distention. The somatic pain is transmitted via the pudendal nerve and enters the spinal cord at the S2-4 level. The paracervical block only blocks the visceral first-stage pathways. A true saddle block (sacral dermatomes only) and the pudendal block work for second-stage somatic pain only, whereas a lumbar epidural or a caudal epidural can be used for both first- and secondstage visceral, as well as somatic, pain relief.
Which sign is associated with placenta previa? (A) Painless vaginal bleeding (B) Uterine irritability (C) Painful vaginal bleeding (D) Coagulopathy
(A) Painless vaginal bleeding Placenta previa is associated with painless vaginal bleeding and in part by malpresentation of the fetus. In contrast, placenta abruption results painful vaginal bleeding,.
Passive diffusion of substances across the placenta is enhanced by: (Choose all the best answers). 1. Decreased maternal protein binding 2. Low molecular weight of the substance 3. High lipid solubility of the substance 4. High degree of ionization of the substance
(A) Passive diffusion is the primary means for the placental transfer of drugs. Factors producing a high diffusion constant or rapid diffusion include decreased maternal protein binding (more drug available to pass out of the circulation), low molecular weight «500 daltons), high lipid solubility, and a low degree of ionization. Neuromuscular drugs have a high degree of ionization (more water soluble) and are nbt transferred across the placenta in significant amounts.
Which antibiotic is classifed as a beta-lactam? (A) Penicillin (B) Gentamicin (C) Erythromycin (D) Ciprofloxacin
(A) Penicillin Gentamicin is an aminoglycoside, erythromycin a macrolide, and ciprofloxacin is classifed as a fluoroquinolone.
Which condition is NOT associated with precipitating unstable angina? (A) Polycythemia (B) Anemia (C) hyrotoxicosis (D) Emotional stress
(A) Polycythemia Rationale: Unstable angina can be precipitated by anemia, thyrotoxicosis, emotional stress, or anything that causes myocardial ischemia due to an increased oxygen demand
Which condition is NOT associated with precipitating unstable angina? (A) Polycythemia (B) Anemia (C) Thyrotoxicosis (D) Emotional stress
(A) Polycythemia Unstable angina can be precipitated by anemia, thyrotoxicosis, emotional stress, or anything that causes myocardial ischemia due to an increased oxygen demand.
What is the gold standard diagnostic test for obstructive sleep apnea? (A) Polysomnography (B) STOP-Bang Questionnaire (C) STOP questionnaire (D) Bang Questionnaire
(A) Polysomnography The STOP-Bang questionnaire is an obstructive sleep apnea screening tool.
What is the primary intracellular cation? (A) Potassium (B) Sodium (C) Calcium (D) Chloride
(A) Potassium Sodium is the primary extracellular cation. Calcium and chloride are minimally concentrated in the intracellular fluid.
Which statements are true regarding gastrointestinal changes during pregnancy? Select (3) three (A) Pregnant patients are considered a " full stomach". (B) Gastric acid increases. (C) Gastric volume increases. (D) Lower esophageal sphincter relaxation occurs due to progesterone and estrogen. (E) Stomach elevates and rotates during pregnancy.
(A) Pregnant patients are considered a " full stomach". (D) Lower esophageal sphincter relaxation occurs due to progesterone and estrogen. (E) Stomach elevates and rotates during pregnancy. Gastric acid and gastric volume are una ected by pregnancy. Mechanical changes that a ect the stomach and lower esophageal sphincter place the parturient at high risk or aspiration
Which local anesthetic is linked to methemoglobinemia? (A) Prilocaine (B) EMLA (C) Lidocaine (D) Cocaine
(A) Prilocaine Methemoglobinemia is caused by prilocaine's metabolic pathway that includes o-toluidine. EMLA cream is associated with skin blanching, erythema, and edema. Cauda equine syndrome has been associated with lidocaine. Cardiac symptoms include profound arrhythmias and hypertension.
What is the underlying pathology of cor pulmonale? (A) Pulmonary hypertension (B) Decreased pulmonary vascular resistance (C) Systemic hypertension (D) Orthostatic hypotension
(A) Pulmonary hypertension The underlying pathology of cor pulmonale is pulmonary hypertension.
Vocal cord paralysis occurred following intubation. What is the most likely cause? (A) Recurrent laryngeal nerve damage (B) Epiglottic damage (C) Esophageal damage (D) Superior laryngeal nerve
(A) Recurrent laryngeal nerve damage Stridor and respiratory distress result rom injury to the superior laryngeal nerve. Unilateral damage to the recurrent laryngeal nerve results in vocal cord paralysis exhibited by hoarseness.
Which are appropriate for inclusion in an epidural steroid injection? Select (3) three (A) Saline (B) Methylprednisolone acetate (C) Triamcinolone diacetate (D) Fentanyl
(A) Saline (B) Methylprednisolone acetate (C) Triamcinolone diacetate Opioids are not indicated.
Following surgery in the lithotomy position the patient exhibits foot drop and the inability to extend the toes. What nerves are most likely injured? (A) Sciatic and common peroneal (B) Femoral and sciatic (C) Common peroneal and femoral (D) Obturator and sciatic
(A) Sciatic and common peroneal Foot drop and the inability to extend the toes are seen with sciatic and common peroneal nerve injury. T ese nerves are the most commonly injured when placed in the lithotomy position. Injury to the obturator and femoral nerves results in a femoral neuropathy demonstrated by decreased hip exion, inability to extend the knee, and/or sensory loss (superior thigh and anteromedial or medial leg).
Which patients are at risk or aspiration? Select (3) three (A) Second trimester parturient (B) Gastroesophageal reflux (C) First trimester parturient (D) NPO >6 hours (E) Third trimester parturient
(A) Second trimester parturient (B) Gastroesophageal reflux (E) Third trimester parturient Patients at greatest risk or aspiration include the 2nd and 3rd trimester parturients, patients with gastroesophageal reflux disease, and those who consumed solid food <6 hours prior to surgery.
When is cell salvage contraindicated? (A) Sepsis (B) Benign tumors (C) Connective tissue disorders (D) Orthopedic conditions
(A) Sepsis Relative contraindications or the use o cell saver include sepsis, malignancies, pharmacologic agents, and hematologic conditions. Cell salvage is used in orthopedic conditions such as major joint replacement.
A 38-year-old male is undergoing a total colectomy under general anesthesia. Urine output has been 20 mUhr for the last 2 hours. Volume replacement has been adequate. The rationale for administering 5 to 10 mg of furosemide to this patient is to A. Offset the effects of increased antidiuretic hormone (ADH B. Improve renal blood flow C. Convert oliguric renal failure to nonoliguric renal failure D. Offset the effects of increased renin E. Promote renal venodilation
(A) Serum ADH levels increase during painful stimulation associated with surgery, as well as during positive-pressure mechanical ventilation. Small doses of furosemide (Le., 0.1 mg/kg) will counteract this effect during surgery.
With which patient would the anesthetist most want to maintain spontaneous ventilation while under general anesthesia? (A) Severe aortic stenosis (B) Severe mitral regurgitation (C) Acute pulmonary edema (D) Mitral valve prolapse
(A) Severe aortic stenosis Positive pressure ventilation decreases the heart's relative preload. Severe aortic stenosis leads to left ventricular diastolic dysfunction secondary to left ventricular hypertrophy. This diastolic dysfunction combined with outflow obstruction makes patients with aortic stenosis extremely sensitive to decreases in preload (left ventricular end diastolic volume). Mitral regurgitation and pulmonary edema may benefit from positive pressure ventilation.
With which of the following preoperative EKG findings will the anesthetist be particularly careful to avoid bradycardia? (A) Sinus rhythm with prolonged QT interval (B) Sinus rhythm with left bundle branch block (C) Sinus rhythm with premature ventricular complexes (D) Atrial fibrillation
(A) Sinus rhythm with prolonged QT interval Long QT may precipitate torsade de pointes. QT interval is rate dependent; slow heart rate is consistent with longer QT interval. Additionally, premature ventricular complexes are more common with bradycardia.
What is the correct order of anatomical structure used when placing an epidural needle? (A) Skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space (B) Skin, subcutaneous tissue, interspinous ligament, supraspinous ligament, ligamentum flavum, epidural space (C) Skin, subcutaneous tissue, interspinous ligament, supraspinous ligament, ligamentum flavum, dura, subarachnoid space (D) Skin, subcutaneous tissue, interspinous ligament, supraspinous ligament, ligamentum flavum, dura, epidural space
(A) Skin, subcutaneous tissue, supraspinous ligament, interspinous ligament, ligamentum flavum, epidural space Once the needle reaches the epidural space, further advancement penetrates the dura reaching the subarachnoid space and presence of cerebrospinal fluid.
A 13-year-old boy is anesthetized with 0.5% isoflurane, 50% N20, and fentanyl for scoliosis repair. SSEP monitoring is conducted during the procedure. Which of the following structures is not involved in conveyance of the stimulus from the posterior tibial nerve to the cerebral cortex? A. Corticospinal tract B. Medial lemniscus C. Brainstem D. Internal capsule E. Dorsal root ganglion
(A) Somatosensory evoked potentials (SSEPs) recorded on the contralateral cerebral cortex are the physiologic response of the nervous system to peripheral nerve stimulation. Extraction of SSEPs from the background EEG is accomplished by computerized signal averaging for summation. SSEPs assess the integrity of the peripheral nerve (usually posterior tibial or median), dorsal column, brainstem, medial lemniscus, internal capsule, and contralateral somatosensory cortex. However, they do not evaluate the integrity of the ventral or lateral spinothalamic tracts or the corticospinal tract.
The greatest source for contamination of the OR atmosphere is leakage of volatile anesthetics is: A. Around the anesthesia mask B. At the vaporizer C.At the rotameter D. At the CÓ absorber E. At the endotracheal tube
(A) Some epidemiology studies suggest that chronic exposure to trace concentrations of volatile anesthetic gases constitutes a health hazard to OR personnel. For this reason, proper and routine use of scavenging systems is recommended in the OR. It is extremely difficult to keep trace volatile anesthetic gas concentrations within safe limits when they are delivered using a face mask. Although all of the choices in this question can contribute as sources of contamination, leakage around the anesthesia face mask poses the greatest threat
Which of the following chemical mediators is released from peripheral afferent C fibers resulting in dull pain? (A) Substance P (B) Glutamate (C) Histamine (D) Serotonin
(A) Substance P Glutamate results in fast sharp pain via Aδ and C nerve fibers. Edema and vasodilatation result from the release of histamine via substance P. Platelets release serotonin following tissue injury reacting with multiple receptors.
Which of the following are pain modulating excitatory neurotransmitters? Select (2) two (A) Substance P (B) Glycine (C) GABA (D) Glutamate (E) Serotonin
(A) Substance P, (D) Glutamate Glycine, enkephalin, norepinephrine, GABA, and serotonin are inhibitory neurotransmitters. Other excitatory substances include calcitonin, aspartate, and adenosine triphosphate.
Which airway block provides anesthesia below the vocal cords? Select (2) two (A) Superior laryngeal nerve block (B) transtracheal block (C) Glossopharyngeal block (D) Instilling local anesthetic onto the vocal cords
(A) Superior laryngeal nerve block (B) transtracheal block A glossopharyngeal nerve block anesthetizes the posterior third of the tongue. Instilling local anesthetic (lidocaine droplet spread) onto the vocal cords provides local anesthesia to the immediate area only.
What actor is increased in a neonate as compared with an adult? (A) Surface area to weight ratio (B) Systolic blood pressure (C) Plasma protein concentration (D) Lung compliance
(A) Surface area to weight ratio Neonates have a relatively larger body surface area to mass ratio which contributes to the risk oF hypothermia. B, C, and D are all decreased in the neonate compared to the adult.
Following administration of 15 mg spinal bupivacaine, the patient's heart rate and blood pressure fall precipitously. What is the cause? (A) Sympathetic blockade (B) Motor blockade (C) Sensory blockade (D) Sensory and motor blockade
(A) Sympathetic blockade Administration of a spinal anesthetic may cause blocking the cardiac accelerators ( 1- 4) and decreasing venous return with resultant bradycardia. Venous return, cardiac output and systemic vascular resistance decrease in response to sympathetic nervous system blockade.
From which of the following blood products would patients be most likely to become infected with syphilis? A. Platelets B. Fresh frozen plasma C. Whole blood D. Packed RBCs E. Cryoprecipitate
(A) Syphilis results from infection with the spirochete Treponema pallidum. The spirochete does not survive at temperatures used to store blood (4°C). Fresh frozen plasma and cryoprecipitate are stored at -18°C or colder. The only blood products capable of transmitting syphilis are those products stored at room temperature, namely platelets. Currently, all blood donors are screened for syphilis. This is not because the disease is commonly spread by transfusion (there are no documented cases of transfusion transmitted syphilis at present), but because a donor who is syphilis positive is at increased risk for transmitting other sexually transmitted diseases, such as hepatitis B, hepatitis C, and HIV. Their blood is not used.
Which of the following is NOT included in tetralogy of Fallot? A. Patent ductus arteriosus B. Right ventricular hypertrophy C. Ventricular septal defect D. Overriding aorta E. Pulmonic stenosis
(A) Tetralogy of Fallot is the most common congenital heart defect associated with a right-to-Ieft intracardiac shunt. This congenital defect is characterized by a tetrad of congenital cardiac anomalies, including a ventricular septal defect, an aorta that overrides the ventricular septal defect, obstruction of the pulmonary artery outflow tract, and right ventricular hypertrophy. The ventricular septal defect is typically large and single, an infundibular pulmonary artery stenosis is usually prominent, and the distal pulmonary artery may be hypoplastic or even absent. Although many patients with tetralogy of Fallot have a patent ductus arteriosus, this is not included in the definition
Accidental injection of air into a peripheral vein would be least likely to result in arterial air embolism in a patient with which of the following anatomic cardiac defects? A. Patent ductus arteriosus B. Eisenmenger's syndrome C. Teratology of Fallot D. Pulmonary atresia with ventricular septal defect E. Tricuspid atresia
(A) The anesthetic management of patients with congenital heart disease requires thorough knowledge of the pathophysiology of the defect. In general, congenital heart defects can be categorized into those that result in left-to-right intracardiac shunting and into those that result in right-to-Ieft shunting. The main feature in congenital heart defects, which result in right-to-Ieft intracardiac shunting, is a reduction in pulmonary blood flow and arterial hypoxemia. The more common congenital heart defects that result in right-to-Ieft intracardiac shunting include tetralogy of Fallot, Eisenmenger's syndrome, Ebstein's malformation of the tricuspid valve, pulmonary atresia with a ventricular septal defect, tricuspid atresia, and patent foramen ovale. Meticulous care must be taken to avoid infusion of air via intravenous solutions, because this can lead to arterial air embolism. Patients with congenital cardiac defects that result in left -to-right intracardiac shunting, such as patent ductus arteriosus, are at minimal risk for arterial air embolism, because blood flow through the shunt is primarily from the systemic vascular system to the pulmonary vascular system.
The portion of the ventilator (Ohmeda 7000, 7810, and 7900) on the anesthesia machine that compresses the bellows is driven by A. Compressed oxygen B. Compressed air C. Electricity alone D. Electricity and compressed oxygen E. Electricity and compressed air
(A) The control mechanism of standard anesthesia ventilators, such as the Ohmeda 7000, uses compressed oxygen (100%) to compress the ventilator bellows and electrical power for the timing circuit.
The reason a 40:60 mixture of helium and Ó is more desirable than a 40:60 mixture of nitrogen and Ó for a spontaneously breathing patient with tracheal stenosis is A. Helium has a lower density than nitrogen B. Helium is a smaller molecule than Ó C. Absorption atelectasis decreased D. Helium has a lower critical velocity for turbulent flow than does Ó E. Helium is toxic to most microorganisms
(A) The critical velocity for helium is greater than that for nitrogen. For this reason, there is less work of breathing when helium is substituted for nitrogen.
A 68-year-old patient is undergoing elective coronary revascularization. Just before cardiopulmonary bypass, the hemoglobin concentration is 8.3 g/dL and platelet count is 253,000/mm3. After cardiopulmonary bypass is initiated, the patient is cooled to 20°C and 2 units of packed red blood cells are transfused because of bleeding. During bypass, the anesthesiologist notices that the platelet count is 10,000/mm3 and the hemoglobin concentration is 8 g/dL. The most likely cause of thrombocytopenia is: A. Sequestration B. Hemolytic transfusion reaction C. Dilutional thrombocytopenia D. Disseminated intravascular coagulation E. Heparin-induced thrombocytopenia
(A) The effects of hypothermia on cardiovascular physiology are related in part to changes in blood viscosity and rheology, fluid and electrolyte balance, and coagulation. The overall effect of hypothermia on the coagulation system is to reduce hemostasis. For example, platelets are readily sequestered reversibly in the portal circulation, and at 20°C there is almost complete sequestration of platelets. However, upon rewarming to 35°C the platelet count returns to normal within approximately I hour. These platelets function normally (as measured by bleeding time) and have a normal life span
A 65-year-old female patient with sepsis is undergoing an emergency exploratory laparotomy. After induction of anesthesia and tracheal intubation, the patient's blood pressure is noted to be 65 systolic with a heart rate of 120 beats/min. Cardiac output determined by a thermodilution pulmonary artery catheter is 13 L/min. Of the following vasopressors the LEAST appropriate choice would be: A. Dobutamine B. Dopamine C. Norepinephrine D. Epinephrine E. Phenylephrine
(A) The etiology of hypotension can be placed into two broad categories: decreased cardiac output and/or decreased systemic vascular resistance. In this case, cardiac output is greater than normal as one often sees in early sepsis. Treatment of this hypotension should be carried out with pharmacologic agents with strong a-agonist properties. Of the choices in this question, phenylephrine is the only drug that is a pure a-agonist. Dopamine in high doses has strong activity but significant ~1 activity and some ~2 activity as well. Norepinephrine likewise possesses strong a activity with some ~1 activity. Vasopressin is a potent vasoconstrictor useful in the management of septic shock. Any of the aforementioned pharmacologic agents could be used to support pressure in patients with sepsis in conjunction with definitive treatment for the septic source. Because dobutamine is predominantly a ~1 agonist, it would be an extremely poor choice for a patient with a high cardiac output in the face of a low systemic vascular resistance
An epidural is placed into a 32-year-old parturient receiving magnesium therapy for preeclampsia. Minutes after administration of the test dose, the bolus infusion is interrupted because of a contraction. After the contraction subsides, a slow epidural injection of bupivacaine is resumed. At the same time the patient complains of shortness of breath. She is panic-stricken and wrestles violently with the nurses who are trying to reassure her. She repeats that she cannot breathe, becomes cyanotic, and loses consciousness. During resuscitation, oozing is noted from the IV sites and a pink froth is noted in the endotracheal tube. The most likely diagnosis is: A. Amniotic fluid embolism B. High spinal C. Intravascular bupivacaine injection D. Magnesium overdose E. Eclampsia
(A) The four cardinal features of amniotic fluid embolism are dyspnea, hypoxemia, cardiovascular collapse, and coma. The patient may develop DIC, seizures, and pulmonary edema from left ventricular failure. Patients with a high spinal or epidural may complain of dyspnea, but they also have marked weakness and would certainly not be able to wrestle or struggle with their health care providers. Patients experiencing an intravascular injection of local anesthetic present with central nervous system (CNS) signs of toxicity (lightheadedness, visual or auditory disturbances, muscular twitching, convulsion, coma) or at higher levels cardiovascular collapse. Magnesium overdosage is also associated with muscle weakness. The typical eclamptic seizure is tonic-clonic. Patients with eclampsia do not complain of dyspnea, although an associated aspiration may produce similar symptoms.
The most common side effect of intraspinal narcotics in the obstetric population is A. Pruritus B. Nausea and vomiting C. Respiratory depression D. Urinary retention E. Headache
(A) The most common side effect of intraspinal narcotics is pruritus. The next most common side effects are nausea and vomiting, followed by urinary retention. Respiratory depression and headache may occur but are relatively infrequent.
The dial of an isoflurane-specific, variable bypass, temperature-compensated, flowover, out-of-circuit vaporizer (Le., modem vaporizer) is set on 2% and the mass spectrometer measures 2% isoflurane vapor from the common gas outlet. The flowmeter is set at a rate of 700 mL/min during this measurement. The output measurements are repeated with the flowmeter set at 100 mL/min and 15 L/min (vapor dial still set on 2%). How will these two measurements compare with the first measurement taken? A. Output will be less than 2% in both cases B. Output will be greater than 2% in both cases C. Output will be 2% at 100 mL/min Ó flow and less than 2% at 15 L/min flow D. Output will be 2% in both cases E. Output will be less than 2% at 100 mL/min and 2% at 15 L/mi.
(A) The output of the vaporizer will be lower at flow rates less than 250 mUmin because there is insufficient pressure to advance the molecules of the volatile agent upward. At extremely high carrier gas flow rates there is insufficient mixing in the vaporizing chamber
When is a type and screen preferable to a type and crossmatch? (A) The probability of trans using blood is low (B) The probability of transfusing blood is high (C) The patient has high risk for alloimmunization (D) The patient has a history of a positive antibody screen
(A) The probability of trans using blood is low A type and screen is pre erable when the probability o trans using blood is low. A type and cross is pre erable when the probability o trans using blood is high.
Which of the following types of regional anesthesia is associated with the greatest serum concentration of lidocaine? A. Intercostal B. Caudal C. Epidural D. Brachial plexus E. Femoral nerve block
(A) The site of injection of the local anesthetic is one of the most important factors influencing systemic local anesthetic absorption and toxicity. The degree of absorption from the site of injection depends on the blood supply to that site. Areas that have the greatest blood supply have the greatest systemic absorption. For this reason, the greatest plasma concentration of local anesthetic occurs after an intercostal block, followed by caudal, epidural, brachial plexus, and femoral nerve block.
A 22-year-old patient is anesthetized for resection of a temporal lobe tumor. Preoperatively, he is lethargic and confused. After induction of general anesthesia, which of the following would be the most appropriate drug to control systemic arterial blood pressure during direct laryngoscopy and tracheal intubation? A. Trimethaphan B. Nitroglycerin C. Hydralazine D. Halothane E. Nitroprusside
(A) The symptoms of lethargy and confusion described in this patient strongly suggest the presence of intracranial hypertension. All of the drugs listed in this question are potent cerebral vasodilators. Trimethaphan blocks neurotransmission at autonomic ganglia. Compared with the other vasodilators listed in this question, for any given degree of reduction in systemic arterial blood pressure, trimethaphan causes the least increase in CBV and ICP. Clinically, trimethaphan is rarely used in neurosurgical patients because of its ability to induce mydrias.
A ventilator pressure-relief valve stuck in the closed position can result in A. Barotrauma B. Hypoventilation C. Hypoxia D. Hyperventilation E. Low breathing circuit pressure
(A) The ventilator pressure-relief valve is pressure controlled via pilot tubing that communicates with the ventilator bellows chamber. As pressure within the bellows chamber increases during the inspiratory phase of the ventilator cycle, the pressure is transmitted via the pilot tubing to close the pressure-relief valve, thus making the patient breathing circuit "gastight." This valve should open during the expiratory phase of the ventilator cycle to allow the release of excess gas from the patient breathing circuit into the waste-gas scavenging circuit after the bellows has fully expanded. If the ventilator pressure-relief valve were to stick in the closed position, there would be a rapid buildup of pressure within the circle system that would be readily transmitted to the patient. Barotrauma to the patient's lungs would result if this situation were to continue unrecognized.
Which of the following statements correctly defines the relationship between minute ventilation (VE), dead space ventilation (Vo), and Pacó? A. If VE is constant and Vo increases, then Pacó will increase B. If V E is constant and V 0 increases, then Pacó will decrease C. If Vo is constant and VE increases, then Pacó will increase D. If Vo is constant and VE decreases, then Pacó will decrease E. None of the above
(A) The volume of gas in the conducting airways of the lungs (and not available for gas exchange) is called the anatomic dead space. The volume of gas in ventilated alveoli that are unperfused (and not available for gas exchange) is called the functional dead space. The anatomic dead space together with the functional dead space is called the physiologic dead space. Physiologic dead-space ventilation can be calculated by the Bohr dead-space equation, which is mathematically expressed as follows: VD/VT = (Pacó - PEC02 ) /Pacó where Vol VT is the ratio of physiologic dead-space ventilation (Vo) to VT, and the subscripts a and E represent arterial and mixed expired, respectively. Of the choices given, only the first is correct. A large increase in physiologic dead-space ventilation will result in an increase in Pacó
In the resting adult, what percentage of total body Ó consumption is due to the work of breathing? A. 2% B. 5% C. 10% D. 20% E. 50%
(A) The work required to overcome the elastic recoil of the lungs and thorax, along with airflow or frictional resistances of the airways, contributes to the work of breathing. When the respiratory rate or airway resistance is high or pulmonary or chest wall compliance is reduced, a large amount of energy is spent overcoming the work of breathing. In the healthy resting adult, only 1% to 2% of total Ó consumption is used for the work of breathing
Uterine blood flow is consistently decreased after the administration of A. Thiopental 4 mg/kg bolus B. Propofol 2 mg/kg bolus C. Ketamine I mg/kg bolus D. Clonidine 300 [J.g epidurally E. Epidural loaded with local anesthetic, uncomplicated by hypotension.
(A) Thiopental causes a transient but consistent 20% to 40% reduction in uterine blood flow (UBF) when used as an induction agent for general anesthesia. UBF is unchanged with a propofol bolus (2 mg/kg) or with an infusion of propofol «450 iJ.g/kg/min when used with 50% nitrous oxide and oxygen), I mg/kg ketamine, epidural clonidine, or a local anesthetic epidural uncomplicated with hypotension. Although based on uterine blood sllldies, propofol appears better than thiopental as an induction agent for cesarean deliveries. Because propofol has been associated with severe bradycardia when used with succinylcholine in pregnant patients, thiopental is more commonly used. This observation needs further study.
Which patients are more likely to experience complications when using a hypotensive technique? Select (2) two (A) Uncontrolled glaucoma (B) History of transient ischemic attack (C) Multiple sclerosis (D) Osteoarthritis
(A) Uncontrolled glaucoma (B) History of transient ischemic attack Patients with cerebrovascular, cardiac, hepatic, uncontrolled glaucoma, and renal disease are not the best candidates for hypotensive anesthesia. Hypotensive anesthesia is relatively contraindicated. Complications including blindness, cardiac (myocardial infarction), stroke, and renal dysfunction (acute tubular necrosis) are possible outcomes.
Which of the following are relative contraindications for regional anesthesia? Select (3) three (A) Uncooperative patient (B) Pre Existing neurological deficits (C) Severe aortic stenosis (D) Patient refusal (E) Stenotic valvular disease
(A) Uncooperative patient (B) Pre Existing neurological deficits (E) Stenotic valvular disease Absolute contraindications for regional anesthesia include severe aortic, mitral stenosis, for hypovolemia; increased intracranial pressure, infection at the site of injection, patient refusal, and bleeding diathesis. Extreme caution is used when considering regional anesthesia or patients with coagulopathies. The risks and benefits must be weighed.
The addition of an intravenous inotropic will tend to move the Frank-Starling curve in which direction? (A) Up (B) Down (C) Left (D) Right
(A) Up Starling's law relates preload (ventricular end-diastolic volume) with stroke volume (or cardiac output) when heart rate and contractility remain constant. If an inotrope exerts its influence on the ventricular myocardium, contractility will increase independently from preload effects. Thus the stroke volume and cardiac output will be higher for a given ventricular end-diastolic pressure.
For any given concentration of volatile anesthetic, the splitting ratio is dependent on which of the following characteristics of that volatile anesthetic? A. Vapor pressure B. Barometric pressure C. Molecular weight D. Specific heat E. Minimum alveolar concentration (MAC) at 1 atmosphere
(A) Vaporizers can be categorized into variable-bypass and measured-flow vaporizers. Measured-flow vaporizers (nonconcentration calibrated vaporizers) include the copper kettle and Vernitrol vaporizer. With measured-flow vaporizers, the flow of oxygen is selected on a separate flowmeter to pass into the vaporizing chamber from which the anesthetic vapor emerges at its saturated vapor pressure. By contrast, in variable-bypass vaporizers, the total gas flow is split between a variable bypass and the vaporizer chamber containing the anesthetic agent. The ratio of these two flows is called the splitting ratio. The splitting ratio depends on the anesthetic agent, temperature, the chosen vapor concentration set to be delivered to the patient, and the saturated vapor pressure of the anesthetic.
A sudden decreased SpO2, blood pressure, and ETCO2 occur during general anesthesia. A mill-wheel murmur exists. What is the most likely cause? (A) Venous air embolism (B) Pneumocephalus (C) Fat embolism (D) Cardiovascular accident
(A) Venous air embolism Classic signs of a venous air embolism include marked hemodynamic changes, falling end-tidal carbon dioxide, increased nitrogen, arrhythmias and a mill-wheel murmur.
Severe hypotension associated with high spinal anesthesia is caused primarily by: A. Decreased cardiac output secondary to decreased preload B. Decreased systemic vascular resistance C. Decreased cardiac output secondary to bradycardia D. Decreased cardiac output secondary to decreased myocardial contractility E. Increased shunting through metarterioles
(A) With a high spinal anesthesia, modest degrees of hypotension in normovolemic patients are due to decreased vascular resistance. Severe hypotension is due to decreased cardiac output caused by decreased preload from peripheral pooling of blood and/or hypovolemia.
The patient arrives in the operating room following a motor vehicle accident. 40% of the body is burned. When is it permissible to use succinylcholine? Select (2) two (A) Within 8 hours of injury. (B) Within 48 hours of injury. (C) After 48 hours of injury. (D) No succinylcholine is used or patients with burns.
(A) Within 8 hours of injury. (B) Within 48 hours of injury. Succinylcholine may be used or burn patients within 48 hours o injury. Significant elevation of potassium occurs when succinylcholine is administered after 48 hours.
What results when a limb tourniquet is released? Select (3) three (A) temperature decrease (B) Metabolic acidosis (C) Metabolic alkalosis (D) temperature increase (E) End-tidal CO2 increase
(A) temperature decrease (B) Metabolic acidosis (E) End-tidal CO2 increase When a tourniquet is released products of cellular metabolic waste enter the circulation. Hypotension, tachycardia and increased minute ventilation occur. The end-tidal CO2 increases along with serum potassium and lactate.
Characteristics of ~2 stimulation include each of the following EXCEPT A. Inhibition of insulin secretion B. Glycogenolysis C. Gluconeogenesis D. Renin secretion E. Uterine relaxation
(A) ~-Adrenergic receptors are responsible for mediating activation of the cardiovascular system, vascular and respiratory smooth muscle relaxation, renin secretion by the kidneys, and several metabolic functions, such as lipolysis, glycogenolysis, and insulin secretion. ~l-Adrenergic receptors primarily mediate the cardiac effects (i.e., heart rate, contractility, and conduction velocity) and the release of fatty acids from adipose tissue, whereas ~2-receptors primarily mediate vascular airway, and uterine smooth muscle tone and glycogenolysis. a-Adrenergic receptors mediate intestinal and urinary bladder-sphincter tone
General anesthesia is induced in a 35-year-old patient for elective cesarean section. No part of the glottic apparatus is visible after two unsuccessful attempts to intubate, but mask ventilation is adequate. The most appropriate step at this point would be A. Wake up the patient B. Use an esophageal-tracheal Combitube C. Attempt a blind nasal intubation D. Continue mask ventilation and cricoid pressure E. Use a laryngeal mask airway
(A)Evaluation of the airway should be performed before the induction of any general anesthetic. In cases where an unrecognized difficult airway exists (unable to perform endotracheal intubation in a reasonable period of time) the patient should be awakened if the procedure is purely elective and the fetus has minimal or no fetal distress (as in this elective case). A regional anesthetic or awake intubation then can be safely performed. In cases of fetal or maternal distress, other options for securing the airway may be necessary
The plasma half-times of which of the following drugs is prolonged in patients with end-stage cirrhotic liver disease? (Select all that apply) 1. Diazepam 2. Pancuronium 3. Lidocaine 4. Procaine
(ALL 1-4) Chronic liver disease may interfere with the metabolism of drugs because of the decreased number of enzyme-containing hepatocytes, decreased hepatic blood flow, or both. Prolonged elimination half-times for morphine, alfentanil, diazepam, lidocaine, pancuronium, and, to a lesser extent, vecuronium have been demonstrated in patients with cirrhosis of the liver. In addition, severe liver disease may decrease the production of cholinesterase (pseudocholinesterase) enzyme, which is necessary for the hydrolysis of ester linkages in drugs such as succinylcholine, mivacurium, and ester local anesthetics such as procaine.
Which of the following intraspinal opioid dose(s) would be acceptable to administer in combination with 12 mg bupivacaine to a parturient about to undergo a cesarean section? (Choose all the best answers). I. 15 mcg fentanyl 2. 5 mcg sufentanil 3. 0.25 mg morphine 4. 15 mcg fentanyl and 0.25 mg morphine
(ALL) Intrathecal opioids are often mixed with local anesthetics to provide better intraoperative and postoperative pain control. Fentanyl is commonly used in doses of 10 to 25 f,Lg, sufentanil in doses of 2.5 to 5.0 f,Lg, and morphine in doses of 0.1 to 0.25 mg. Some anesthesiologists mix morphine with fentanyl because morphine is slow in onset but has a long duration of action and fentanyl is faster in onset but has a short duration of action.
15-methyl PGF2a is administered directly into the myometrium to treat uterine atony in a 28-year-old mother. Possible complications from treatment with this drug include :(Choose all the best answers). 1. Nausea and vomiting 2. Bronchospasm 3. Fever 4. Hypoxemia
(ALL) 15-methyl PGF2a (carboprost, Hemabate) is the preferred prostaglandin for use in the treatment of refractory uterine atony (after oxytocin). The dose is 250 f,Lg 1M. It has several important side effects, such as bronchospasm, ventilation-to-perfusion (V /Q) mismatch with an increase in intrapulmonary shunting, and hypoxemia. Other side effects include nausea, vomiting, fever, and diarrhea
Which of the following is decreased during pregnancy? (Choose all the best answers). I. Creatinine. 2. Minimum alveolar concentration (MAC) for volatile anesthetics. 3. Plasma cholinesterase. 4. Amount of local anesthetics required for lumbar epidurals and spinals.
(ALL) Plasma creatinine is decreased to about 0.5 to 0.6 mg/dL by the end of pregnancy because the cardiac output and the renal blood flow are increased. Parturients are more sensitive to volatile (lower MAC values) and local anesthetics than are nonpregnant patients. The mechanism of this reduction in anesthetic requirement is not known but may be related to elevated progesterone levels. The decrease in plasma cholinesterase activity of about 25% during pregnancy is not clinically significant in terms of prolonging the half-life of drugs such as succinylcholine
Tocolytics useful in the treatment of preterm labor include: :(Choose all the best answers). 1. Magnesium sulfate 2. Nifedipine 3. Terbutaline 4. Indomethacin
(ALL) There are several drugs that can be used for tocolytic therapy for preterm labor. Most commonly, MgS04 and/or J3-adrenergic agonists (ritodrine, terbutaline) are used. Indomethacin and nifedipine have recently been used in selected cases
12. The 02 pressure-sensor shutoff valve requires what Ó pressure to remain open and allow N20 to flow into the N20 rotameter? A. 10 psi B. 25 psi C. 50 psi D. 100 psi E. 600 psi
(B) Fail-safe valve is a synonym for pressure-sensor shutoff valve. The purpose of the fail-safe valve is to prevent delivery of hypoxic gas mixtures from the anesthesia machine to the patient due to failure of the Ó supply. When the Ó pressure within the anesthesia machine decreases below 25 psi, this valve discontinues the flow of N20 or proportionally decreases the flow of all gases. It is important to realize that this valve will not prevent delivery of hypoxic gas mixtures or pure N20 when the Ó rotameter is off, but the Ó pressure within the circuits of the anesthesia machine is maintained by an open Ó compressed-gas cylinder or central supply source. Under these circumstances, an Ó analyzer would be needed to detect delivery of a hypoxic gas mixture.
The dose of adenosine necessary to convert paroxysmal supraventricular tachycardia to normal sinus rhythm should be initially reduced A. In patients receiving theophylline for chronic asthma B. In patients with a history of arterial thrombotic disease taking dipyridamole C. In patients with a history of chronic renal failure D. In patients with hepatic dysfunction E. In chronic alcoholics
(B) Adenosine in doses of 6 to 12 mg IV can be very effective in the treatment of supraventricular tachycardias, including those associated with Wolff-Parkinson-White syndrome. The drug is rapidly metabolized such that it is not influenced by liver or renal dysfunction. Its effects, however, can be markedly enhanced by drugs that interfere with nucleotide metabolism such as dipyridamole. Administration of the usual dose of adenosine to a patient receiving dipyridamole may result in asystole. Methylxanthines, such as caffeine, theophylline, and amrinone, are competitive antagonists of this drug, and doses may need to be adjusted accordingly.
Each of the following is associated with an increased incidence of pulmonary artery rupture in patients with pulmonary artery catheters EXCEPT A. Hypothermia B. Presence of pulmonary artery atheromas C. Old age D. Anticoagulation E. Pulmonary artery catheter migration
(B) Pulmonary artery rupture is a disastrous but fortunately rare complication associated with the use of pulmonary artery catheters. The hallmark of pulmonary artery rupture is hemoptysis, which may be minimal or copious. Efforts should be made to separate the lungs. This can be achieved by endobronchial intubation with a double-lumen endotracheal tube. The presence of atheromas in the pulmonary artery is not associated with an increased risk of pulmonary artery rupture. Atheromatous changes are usually minimal or absent in the middle and distal portions of the pulmonary artery (Le., in the segments where the tip of the pulmonary artery catheter typically resides
Under maximum stress, how much cortisol is produced per day? A. 50 mg B. 150 mg C. 250 mg D. 350 mg E. Up to 1000 mg
(B) The daily production of cortisol under normal circumstances is approximately 20 mg. Under maximum stress, daily cortisol production can increase to 150 mg
A 62-year-old patient scheduled for elective repair of an abdominal aortic aneurysm develops a wide complex tachycardia (heart rate 150) during induction of anesthesia. Blood pressure is 110/78. Which of the following drugs would be most useful in the management of this dysrhythmia? A. Lidocaine, 100 mg IV B. Amiodarone, 150 mg IV over 10 minutes C. Adenosine, 6 mg rapidly over 3 seconds D. Verapamil, 5 to 10 mg IV E. Esmolol, 35 mg IV
(B) The patient described in this question has a wide complex tachycardia of undetermined origin. Differentiation of a ventricular from a supraventricular etiology is useful in determining the most efficacious therapy. A heart rate of 150/min could represent ventricular tachycardia (usual range 150 to 250), paroxysmal supraventricular tachycardia (also has a range of 150 to 250/min), or atrial flutter (rate of 150/min is common 2: 1 heart block). Without additional history or information, this rhythm should be treated as "wide complex tachycardia" of unknown origin. According to the 2000 Advanced Cardiac Life Support (ACLS) guidelines, therapy could include amiodarone, procainamide, or DC cardioversion. Because it is possible that this rhythm could be true ventricular tachycardia, use of adenosine for wide complex tachycardia of unknown origin is controversial and is discouraged. Adenosine should only be used when the tachycardia is strongly suspected to be supraventricular in origin. Because the rhythm could be a paroxysmal supraventricular tachycardia or atrial flutter with heart block, lidocaine would not be a useful therapy. Ibutilide is used to treat new-onset atrial fibrillation or atrial flutter
A 66-year-old patient is undergoing a three-vessel coronary artery bypass operation. Anticoagulation is achieved with 20,000 units of heparin. How much protamine should be administered to this patient to completely reverse the heparin after cardiopulmonary bypass? A. 150 mg B. 250 mg C. 350 mg D. 450 mg E. 550 mg
(B) Twenty thousand units of heparin is equal to 200 mg. Heparin can be neutralized by administration of 1.0 to 1.5 mg of protamine for each milligram of heparin. Protamine is a basic protein that combines to the acidic heparin molecule to produce an inactive complex that has no anticoagulant properties. The half-life of heparin is 1.5 hours at 37°C. At 25°C metabolism of heparin is minimal
How much additional fluid will you administer to a patient undergoing a herniorrhaphy? (A) 4-8 mL/kg (B) 0-2 mL/kg (C) 2-4 mL/kg (D) 10 mL/kg
(B) 0-2 mL/kg
What is the normal V/Q ratio? (A) 1 (B) 0.8 (C) 2 (D) 0.5
(B) 0.8 Normally, ventilation (V) is approximately 4 L/min, whereas pulmonary blood ow (Q) is approximately 5 L/min. Therefore, the ventilation perfusion ratio (V/Q) or the whole lung is 0.8.
A 150-kg male patient has a serum sodium concentration of 110 mEq/L. How much sodium would be needed to bring the serum sodium to 125 mEq/L? (A) 750 mEq (B) 1,350 mEq (C) 2,400 mEq (D) 3,200 mEq
(B) 1,350 mEq Using the sodium deficit formula, the answer will be 1,350 mEq. The sodium de cit equation is the following: Sodium deficit (mEq) = ([Na] goal - [Na] plasma) × TBW; TBW = body weight (in kg) × 60%.
Removal of epidural catheters should be delayed for a minimum of how many hours following the administration of prophylactic low molecular weight heparin (LMWH)? (A) 1 hour (B) 10 hours (C) 3 hours (D) 6 hours
(B) 10 hours Because of the risk of spinal hematomas, epidural catheters should be removed 2 hours prior to the rst dose of LMWH. I already present, epidural catheters should be removed greater than 10 hours a ter the last dose of LMWH
A patient is scheduled for a thoracotomy. A thoracic epidural is placed. What volume of local anesthetic will you use? (A) 15 mL (B) 10 mL (C) 18 mL (D) 20 mL
(B) 10 mL Cervical and thoracic epidural volume is calculated based upon 0.7-1.0 mL/segment. For lumbar epidural anesthesia, 1-2 mL/segment volume is administered.
A patient who takes ticlopidine requests a spinal anesthetic for a total knee replacement. What is the waiting period for ticlopidine? (A) 7 days (B) 14 days (C) 48 hour (D) 8 hour
(B) 14 days The waiting period to provide regional anesthesia for patients taking antiplatelet drugs varies. The waiting period or clopidogrel is 7 days; abciximab is 48 hours; and epti batide is 8 hours.
Intracranial hypertension is defined as a sustained increase in intracranial pressure (ICP) above A. 5 mm Hg B. 15 mmHg C. 25 mm Hg D. 40 mm Hg E. None of the above
(B) 15 mmHg Elevated ICP frequently is the final stage of a pathologic cerebral insult (e.g., head injury, intracranial tumor, subarachnoid hemorrhage, metabolic encephalopathy, or hydrocephalus). The intracranial contents consist of three components: brain parenchyma (80% to 85%), blood (3% to 6%), and csr (5% to 15%). None of these components is compressible; accordingly, an increase in the volume of any of these requires a compensatory decrease in the volume of one or both of the other components to avoid the development of intracranial hypertension. NormalJCP is less than 15 mm Hg. As measured in the supine position, intracranial hypertension is defined as a sustained increase in JCP above 15 to 20 mm .
The anatomic dead space in a 70-kg male is A. 50 mL B. 150 mL C. 250mL D. 500 mL E. 700 to 1000 mL
(B) 150 ml. Also see explanation to question 103. The conducting airways (trachea, right and left mainstem bronchi, and lobar and segmental bronchi) do not contain alveoli and therefore do not take part in pulmonary gas exchange. These structures constitute the anatomic dead space. In the adult, the anatomic dead space is approximately 1 mL/lb or 2 mL/kg. The anatomic dead space increases during inspiration because of the traction exerted on the conducting airways by the surrounding lung parenchyma. In addition, the anatomic dead space depends on the size and posture of the subjec
By what percentage does cerebral blood flow (CBF) change for each millimeter mmHg increase in Pacó? A. 1% B. 2% C. 7% D. 10% E. 25%
(B) 2% Hyperventilation of the lungs causes constriction of cerebral blood vessels, which reduces global cerebral blood flow (CBF) and cerebral blood volume (CBV). This effect is mediated by changes in the pH induced in the extracellular fluid. In contrast to autoregulation, CÓ reactivity is preserved in most patients with severe brain injury; thus, hyperventilation can rapidly lower intracranial pressure (ICP) through the reduction in CBV. Although the effects of hyperventilation on CBV and ICP are almost immediate, the duration of effect wanes after 6 to 10 hours of hyperventilation and may last up to 24 to 36 hours, because the pH of the extracellular fluid equilibrates to the lower Pacó level. Generally speaking, CBF increases (or decreases) by approximately 2% for each mm Hg increase (or decrease) in Pacó• CBF increases (or decreases) 1 mUIOO g/min per I mm Hg increase (or decrease) in Pacó• Because normal global CBF is 50 mLllOO g/min, a I mL/IOO g/min alteration in CBF represents a 2% change.
How much blood could a 90-kg, adult female patient lose and still maintain a hematocrit of 30%, provided the preoperative hematocrit was 42%? (A) 702 mL (B) 2,106 mL (C) 2,457 mL (D) 5,850 mL
(B) 2,106 mL Step 1: Calculate EBV or a female: 90 kg × 65 mL/kg = 5850 mL (D is incorrect). Step 2: Calculate RBCV42: 5850 × 42% = 2,457 mL (C is incorrect). Step 3: Calculate RBCS30: 5850 × 30% = 1,755 mL. Step 4: Calculate red cell loss at 30%: 2,457-1,755 = 702 mL (A is incorrect). Step 5: Calculate ABL: 702 mL × 2 = 2,106 mL (B is correct).
The patient received a Bier Block for hand surgery. The case was completed in 10 minutes. When will you deflate the tourniquet? (A) 10 minutes a ter the local anesthetic is injected. (B) 20 minutes a ter the local anesthetic is injected. (C) 30 minutes a ter the local anesthetic is injected. (D) 40 minutes a ter the local anesthetic is injected.
(B) 20 minutes a ter the local anesthetic is injected. The tourniquet should remain inflated for a minimum of 20 minutes after the local anesthetic is injected to avoid local anesthetic toxicity.
The anesthesia plan includes using topical cocaine for nasal surgery. What is the maximum dose? (A) 50 mg (B) 200 mg (C) 400 mg (D) 40 mg
(B) 200 mg To avoid symptoms associated with overdose (arrhythmia, convulsions, respiratory, and cardiac arrest) use no > 200 mg (5 mL o 4% solution).
A patient's lab values reveal digoxin toxicity and hyperkalemia. Which option for treating for hyperkalemia will you need to avoid in this patient? (A) 10 units regular insulin with 30-50 gm dextrose 50% IV (B) 3-5 mL of 10% calcium chloride IV (C) 45 mEq sodium bicarbonate IV (D) 30 gm sodium polystyrene PR
(B) 3-5 mL of 10% calcium chloride IV Administering calcium to patients who take digoxin potentiates digoxin toxicity. This patient is digoxin toxic so administering calcium will only cause further deterioration
What is the lowest recommended PaCO2 if hyperventilation is used during intracranial tumor resection? (A) 35 mmHg (B) 30 mmHg (C) 25 mmHg (D) 20 mmHg
(B) 30 mmHg The recommended PaCO2 range during induced hypocapnia is 30-35 mmHg.
What is the maintenance intravenous fluid replacement rate for a toddler weighing 12 kg? (A) 48 mL/hr (B) 44 mL/hr (C) 40 mL/hr (D) 36 mL/hr
(B) 44 mL/hr Hourly maintenance fluid rate is calculated as 4 mL/kg/hr up to 10 kg of body weight, 2 mL/kg/hr for the second 10 kg of body weight, and 1 mL/kg/hr for every kilogram beyond 20
What is the average blood volume of an 80-kg male? (A) 5 L (B) 6 L (C) 5.2 L (D) 6.4 L
(B) 6 L The average blood volume for a male is 75 mL/kg; 65 mL/kg or a female; and 80 mL/kg for an infant.
Which patient requires the highest minimum alveolar concentration (MAC)? (A) Newborn of 35 weeks' gestation (B) A 4-month-old (C) An 18-month-old (D) A 3-year-old
(B) A 4-month-old Infants >3 but <6 months of age have the highest MAC.
What finding is most likely during preoperative examination of an awake and alert patient with a posterior cerebral artery aneurysm? (A) Brown-Séquard syndrome (B) Abnormal gaze or pupil response (C) Decorticate posturing (D) Hypertensive crisis
(B) Abnormal gaze or pupil response Oculomotor palsy may result from an aneurysm in this area due to close proximity of these structures.
Advantages of spinal anesthesia over epidural anesthesia for cesarean section include: I. Decreased dose of local anesthetic 2. Predictability of segmental analgesic spread 3. Speed of onset of analgesia 4. Less marked hypotension
(B) Advantages to using spinal instead of epidural anesthesia for cesarean section include faster onset of action, a significant decrease in total amount of anesthetics needed, and less time spent with the patient. However, because of faster onset of spinal anesthesia, hypotension is more frequent and vasopressor treatment more commonly needed despite "adequate hydration." The spread of spinal anesthesia is less controlled and hence more unpredictable than with epidural anesthesia.
The correct arrangement of local anesthetics in order of their ability to produce cardiotoxicity from most to least is: A. Bupivacaine, lidocaine, ropivacaine B. Bupivacaine, ropivacaine, lidocaine C. Lidocaine, bupivacaine, ropivacaine D. Ropivacaine, bupivacaine, lidocaine E. Lidocaine, ropivacaine, bupivacaine
(B) All local anesthetics have a dose-dependent depression effect on cardiac contractility and conduction velocity. The cardiodepressant effect generally parallels the anesthetic potency. Bupivacaine has been shown to be 16 times more toxic than lidocaine, well out of proportion to the potency ratio and two times more toxic than ropivacaine despite similar nerve-blocking potency.
A 25-year-old healthy patient is anesthetized for a femoral hernia repair. Anesthesia is maintained with isoflurane and N20 50% in Ó and the patient's lungs are mechanically ventilated. Suddenly, the "low arterial saturation" warning signal on the pulse oximeter alarms. After the patient is disconnected from the anesthesia machine, he is ventilated with an Ambu bag with 100% Ó without difficulty and the arterial saturation quickly improves. During inspection of your anesthesia equipment, you notice that the bobbin in the 02 rotameter is not rotating. This most likely indicates: A. The flow of N20 through the Ó rotameter B. No flow of 02 through the 02 rotameter C. A flow of Ó through the Ó rotameter that is markedly lower than indicated D. A leak in the 02 rotameter above the bobbin E. A leak in the 02 rotameter below the bobbin
(B) All of the choices listed in this question can potentially result in inadequate flow of 02 , to the patient; however, given the description of the problem, no flow of 02 , through the 02, rotameter is the correct choice. In a normally functioning rotameter, gas flows between the rim of the bobbin and the wall of the Thorpe lube, causing the bobbin to rotate. If the bobbin is rotating you can be certain that gas is fl owing through the rotameter and that the bobbin is not stuck.
Which of the following terms is defined as perception of an ordinary non-noxious stimulus as pain? (A) Hyperalgesia (B) Allodynia (C) Hyperesthesia (D) Dysesthesia
(B) Allodynia Allodynia is a perception o an ordinary non-noxious stimulus as pain
Each of the following will shift the oxyhemoglobin dissociation curve to the right EXCEPT A. Volatile anesthetics B. Decreased Páo C, Decreased pH D. Increased temperature E. Increased red blood cell 2,3-DPG content
(B) Also see explanation to questions 108 and 109. In addition to the items listed in this question, other factors that shift the oxyhemoglobin dissociation curve to the right include pregnancy and all abnonnal hemoglobins such as hemoglobin S (sickle cell hemoglobin). For reasons unknown, volatile anesthetics increase the Pso of adult hemoglobin by 2 to 3.5 mm Hg. A rightward shift of the oxyhemoglobin dissociation curve will decrease the transfer of 02 from alveoli to hemoglobin and improve release of 02 from hemoglobin to peripheral tissues
The most important determinant of resistance to laminar gas flow through a tube is the A. Length of the tube B. Radius of the tube C. Viscosity of the gas D. Density of the gas E. Mass of the gas
(B) Also see explanation to questions I and 21. Laminar flow occurs when a substance flows down a parallel-sided tube at a rate less than critical velocity. Resistance to laminar gas flow through a tube is directly proportional to the viscosity of the gas and length of the tube and is inversely proportional to the fourth power of the radius of the tube. This is known as the Hagan-Poiseuille Law of Friction. Based on this law, a change in the radius of the tube will have the greatest effect on the resistance to laminar gas flow though a tube.
A 3-year-old child with severe congenital facial anomalies is anesthetized for extensive facial reconstruction. After inhalation induction with sevoflurane and oral tracheal intubation, a 22-gauge arterial line is placed in the right radial artery. The arterial cannula is then connected to a transducer that is located 10 cm below the patient's heart. After zeroing the arterial line at the transducer, how will the given pressure compare with the true arterial pressure? A. It will be 10 mm Hg higher B. It will be 7.5 mm Hg higher C. It will be the same D. It will be 7.5 mm Hg lower E. It will be 10 mm Hg lower
(B) Also see explanations to questions 3 and 13. In this question the reference point was the transducer, which was located 10 cm below the level of the patient's heart. Thus, there is an approximate 10 cm H20 fluid column from the level of the patient's heart to the transducer. This will cause the pressure reading from the transducer system to read approximately 7.5 mm Hg higher than a true arterial pressure of the patient. A 20-cm column of H20 will exert a pressure equal to 14.7 mm Hg.
Which of the following signs and symptoms is NOT associated with amniotic fluid embolism? A. Dyspnea B. Hypertension C. Bleeding (disseminated intravascular coagulation) D. Hypoxemia E. Seizures
(B) Amniotic fluid embolism is a very rare but serious complication of labor and delivery that results from the entrance of amniotic fluid and constituents of amniotic fluid into the maternal systemic circulation. For this to occur, the placental membranes must be ruptured, and abnormal open sinusoids at the uteroplacental site or lacerations of endocervical veins must exist. The onset of amniotic fluid embolism is associated with dyspnea, severe hypotension, and hypoxemia. Disseminated intravascular coagulation (Ole) occurs in as many as 40% of these patients, whereas seizures occasionally occur.
Which of the following is true regarding a patient with septal defects? (A) An increase in SVR relative to PVR will increase cyanosis. (B) An increase in PVR relative to SVR avors right to left shunting. (C) An increase in PVR relative to SVR will decrease risk of paradoxical air embolism. (D) Eisenmenger syndrome is most often due to left ventricular hypertrophy.
(B) An increase in PVR relative to SVR avors right to left shunting. When right-sided pressures exceed let sided pressures with septal defects, a mixing of un-oxygenated venous blood with the oxygenated blood can lead to cyanotic states, a right to left shunting. This also can lead to right-sided air bubbles moving across the septum to the left, causing paradoxical air embolism to the cerebral or coronary arterial circulation. The reverse is true. An increase in SVR (with increased left-sided pressures) will reverse the right-to-left shunt and decrease cyanosis. Eisenmenger syndrome is the result of chronic left-to-right shunts which increase right-sided pressures, resulting in right-ventricular hypertrophy with elevated right-sided pressures. This will result in a reversal of the pressure gradient, reversing the shunt to become a right-to-left shunt.
Which is true regarding morbidity and mortality in pediatric anesthesia? (A) Anesthetic risk is directly related to patient age. (B) Anesthetic risk is greatest in patients younger than 1 year. (C) Anesthetic risk is greater now than in the past. (D) Anesthetic risk is similar throughout childhood
(B) Anesthetic risk is greatest in patients younger than 1 year. Pediatric anesthetic morbidity and mortality are inversely related to age with greatest risk in patients younger than 1 year
With regard to regulation of blood flow, the correct order of vascular responsiveness to Pacó from most to least sensitive is: A. Cerebrum> spinal cord> cerebellum B. Cerebrum> cerebellum> spinal cord C. Cerebellum> cerebrum> spinal cord D. Cerebellum> spinal cord> cerebrum E. Spinal cord> cerebrum> cerebellum
(B) Arterial carbon dioxide tension (Pacó) is one of the most important extracerebral biochemical factors regulating CBF. The cerebral vasculature is most sensitive to changes in Pacó within the physiologic range (Le., approximately 20 to 80 mm Hg). In general, the regional sensitivity of the cerebral vasculature to changes in Pacó (Le., CÓ responsiveness) is directly proportional to the resting CMR for each region of the brain. Regional CÓ responsiveness is greatest in the cerebrum, less in the cerebellum, and least in the spinal cord
The rational for storage of platelets at room temperature (22°C) is A. It maintains platelet count B. It optimizes platelet function C. It reduces the chance for infection D. It decreases the incidence of allergic reactions E. There is less splenic sequestration
(B) At a pH below 6.0 or in cold temperatures such as 4°C (the temperature used for blood storage), platelets undergo irreversible shape changes. The optimal temperature for platelet storage is 22°C ± 2°C or room temperature. There are two major problems with platelet storage at this Blood Products, Transfusion, and Fluid Therapy 171 recommended temperature. First, the pH falls because of platelet metabolism. Second, bacterial growth is possible, which could potentially lead to sepsis and death. To minimize these problems platelet storage is limited to 5 days at 22°C
Following general endotracheal anesthesia, the patient is in respiratory distress and is unable to speak. What nerve(s) may be injured? (A) Unilateral recurrent laryngeal nerve (B) Bilateral superior laryngeal nerve (C) Unilateral superior laryngeal nerve (D) Bilateral vagus nerves
(B) Bilateral superior laryngeal nerve Areas of the anterior shoulder are supplied by the superficial cervical plexus, which passes through the platysma at the posterior sternocleidomastoid (SCM) giving of superficial and deep branches. The superficial cervical plexus innervates the skin and the superficial structures of the head, neck, and shoulders. It lies in the plane just behind the SCM and can be blocked with a field block at that location.
The blood volume of a 10-kg, l-year-old infant is A. 650mL B. 800 mL C. 1100 mL D. 1300 mL E. 1500 m
(B) Blood volume decreases with age. A preterm newborn has a blood volume of 100 to 120 mL/kg; a term newborn has a blood volume of about 85 to 90 mL/kg; an infant has a blood volume of 80 mL/kg; a 5-year-old child has a blood volume of 70 to 75 mL/kg; and an adult has a blood volume of 65 mL/kg. This 10-kg, I-year-old infant would have an estimated blood volume of 800 mL.
The leftward shift of the oxyhemoglobin dissociation curve caused by hypocarbia is known as the A. Fick principle B. Bohr effect C. Haldane effect D. Law of Laplace E. None of the above
(B) Bohr effect. The effects of Pacó and pH on the position of the oxyhemoglobin dissociation curve is known as the Bohr effect. Hypercarbia and acidosis shift the curve to the right, and hypocarbia and alkalosis shift the curve to the left. The Bohr effect is attributed primarily to the action of CÓ and pH on erythrocyte 2,3-DPG metabolism.
In the supine position, what nerve injury is associated with arm abduction >90 degrees and lateral rotation of the head? (A) Ulnar nerve (B) Brachial plexus (C) Radial nerve (D) Suprascapular nerve
(B) Brachial plexus Ulnar nerve symptoms may result from injury to the brachial plexus. Keeping the arms abducted <90 degrees as well as proper head alignment minimizes stretching of the brachial plexus.
Which surgical procedures pose the lowest risk for myocardial infarction within 30 days of surgery? Select (3) three (A) Liver transplant (B) Breast reduction (C) Hysterectomy (D) Cataract (E) Prostatectomy
(B) Breast reduction (C) Hysterectomy (D) Cataract Liver transplant and prostatectomy are considered intermediate risk carrying a 1-5% likelihood o myocardial infarction following surgery. Vascular and aortic procedures carry the highest risk o in arct (>5%)
The correct arrangement of local anesthetics in order of their ability to produce cardiotoxicity from most to least is A. Bupivacaine, lidocaine, ropivacaine B. Bupivacaine, ropivacaine, lidocaine C. Lidocaine, bupivacaine, ropivacaine D. Ropivacaine, bupivacaine, lidocaine E. Lidocaine, ropivacaine, bupivacaine
(B) Bupivacaine, ropivacaine, lidocaine All local anesthetics have a dose-dependent depression effect on cardiac contractility and conduction velocity. The cardiodepressant effect generally parallels the anesthetic potency. Bupivacaine has been shown to be 16 times more toxic than lidocaine, well out of proportion to the potency ratio and two times more toxic than ropivacaine despite similar nerve-blocking potency
Effective inflation of an intra-aortic balloon catheter should occur at the same time as which of the following? A. Immediately after P wave on ECG B. Immediately after closure of aortic valve C. During opening of the aortic valve D. During systolic upstroke on arterial tracing E. At midpoint of QRS complex
(B) By deflating just before ventricular systole, an intra-aortic balloon pump (IABP) is designed to reduce aortic pressure and afterload, thereby enhancing left ventricular ejection and reducing wall tension and oxygen consumption. By inflating in diastole, just after closure of the aortic valve, diastolic aortic pressure and coronary blood flow are increased. Thus proper timing of inflation and deflation is crucial to correct functioning of an IABP. The P wave on the ECG is a late diastolic event and inflating the IABP just after the P wave would minimize augmentation of diastolic coronary blood flow. In addition, inflation of the device that late in diastolic would risk having the balloon inflated during ventricular systole, which would dramatically increase ventricular afterload and worsen the myocardial oxygen supply and demand balance. Similarly, the midpoint of the QRS complex represents the electrical activation of the ventricles, which heralds the end of ventricular diastole, a time when the balloon should be deflating before ventricular ejection
What is the level of the larynx in a child? (A) C1-C3 (B) C2-C4 (C) C3-C5 (D) C4-C7
(B) C2-C4 The larynx in a small child is adjacent to cervical vertebrae 2-4 with the glottis adjacent to C4.
How much will CBF increase in a patient whose Pacó is increased from 35 to 45 mm Hg? A. There is no relationship between Pacó and CBP B. 10 mLIl 00 g/min C. 25 mLllOO g1min D. 40 mLll 00 g1min E. 50 mLll 00 g/min
(B) CBF will increase by approximately I mL/IOO g/min for every 1 mm Hg increase in Pacó, (i.e., approximately 2%). This effect is caused by CÓ-mediated decrease in the pH of the extracellular fluid surrounding the cerebral vessels, which causes cerebral vasodilatation. The pH changes rapidly because CÓ diffuses freely across the cerebral vascular endothelium into the extracellular fluid. However, the change in pH wanes after 6 to 10 hours because extracellular fluid pH is gradually normalized by reabsorption of HCO) and excretion of H+ by the kidneys. An increase in Pacó of 10 mm Hg (from 35 to 45 mm Hg) will result in an increase in CBP of approximately 10 rnL/I00 glmin
Which diagnostic finding is consistent with intracranial hypertension? (A) MRI with a 0.5 cm midline brain shift (B) CT with a 0.5 cm midline brain shift (C) CT with contrast with a 0.4 cm midline brain shift (D) MRI with a 0.4 cm midline brain shift
(B) CT with a 0.5 cm midline brain shift A cat scan (CT ) that evidences a 0.5 midline brain shift represents a finding consistent with intracranial hypertension.
Which are mechanisms of action for gabapentin? Select (2) two (A) GABA agonist effect (B) Calcium channel blockade (C) Excitatory neurotransmitter inhibition (D) Inhibition of prostaglandin synthesis
(B) Calcium channel blockade (C) Excitatory neurotransmitter inhibition Possible mechanisms include calcium or sodium channel blockade and inhibition o excitatory neurotransmitters in the central nervous system
Which two lung pathologies are Forms of COPD? Select (2) two (A) Asthma (B) Chronic bronchitis (C) Aspiration pneumonitis (D) Emphysema
(B) Chronic bronchitis (D) Emphysema Emphysema and chronic bronchitis provide the prototype o pathological changes in COPD.
What complication is associated with using 6% hetastarch in volumes > 20 mL/kg? (A) Interference with blood typing (B) Coagulopathy (C) Kidney failure (D) Anaphylaxis
(B) Coagulopathy Hetastarch in doses > 20 mL/kg has been known to produce coagulopathy. Dextran I doses > 20 mL/kg is associated with interference with blood typing and kidney failure. Unlike dextran, which is antigenic and known to cause anaphylaxis, hetastarch is nonantigenic.
Select the FALSE statement. A. If a Magill forceps is used for a nasotracheal intubation, the right nares is preferable for insertion of the nasotracheal tube B. Extension of the neck can convert an endotrache.al intubation to an endobronchial intubation C. Bucking signifies the return of the coughing reftex D. Postintubation pharyngitis is more likely to occur in females E. Stenosis becomes symptomatic when the adult tracheal lumen is reduced to less than 5 mm.
(B) Complications of tracheal intubation can be divided into those associated with direct laryngoscopy and intubation of the trachea, tracheal tube placement, and extubation of the trachea. The most frequent complication associated with direct laryngoscopy and tracheal intubation is dental trauma. If a tooth is dislodged and not found, radiographs of the chest and abdomen should be taken to determine whether the tooth has passed through the glottic opening into the lungs. Should dental trauma occur, immediate consultation with a dentist is indicated. Other complications of direct laryngoscopy and tracheal intubation include hypertension, tachycardia, cardiac dysrhythmias, and aspiration of gastric contents. The most common complication that occurs while the endotracheal tube is in place is inadvertent endobronchial intubation. Flexion, not extension, of the neck or change from the supine to the head-down position can shift the carina upward, which may convert a mid-tracheal tube placement into a bronchial intubation. Extension of the neck can cause cephalad displacement of the tube into the pharynx. Lateral rotation of the head can displace the distal end of the endotracheal tube approximately 0.7 cm away from the carina. Complications associated with extubation of the trachea can be immediate or delayed. The two most serious immediate complications associated with extubation of the trachea are laryngospasm and aspiration of gastric contents. Laryngospasm is most likely to occur in patients who are lightly anesthetized at the time of extubation. If laryngospasm occurs, positive-pressure mask-bag ventilation with 100% 02 and forward displacement of the mandible may be sufficient treatment. However, if laryngospasm persists, succinylcholine should be administered intravenously or intramuscularly. Pharyngitis is another frequent complication after extubation of the trachea. This complication occurs most commonly in females, presumably because of the thinner mucosal covering over the posterior vocal cords compared with males. This complication usually does not require treatment and spontaneously resolves in 48 to 72 hours. Delayed complications associated with extubation of the trachea include laryngeal ulcerations, tracheitis, tracheal stenosis, vocal cord paralysis, and arytenoid cartilage dislocation.
What mechanism facilitates heat loss through air currents? (A) Radiation (B) Convection (C) Conduction (D) Evaporation
(B) Convection Evaporative heat loss results fluid loss through the skin and respiratory system. Conductive heat loss occurs when direct contact between cold and warm objects. Radiation involves the transfer of heat from infrared rays. Convective heat loss requires currents and is dependent on thermal gradients.
What is the efferent limb of the oculocardiac reflex? (A) Cranial nerve V (B) Cranial nerve X (C) Cranial nerve I (D) Cranial nerve III
(B) Cranial nerve X Trigeminal (CN V) afferent and vagal (CN X) efferent pathways comprise the oculocardiac reflex.
Critical CBF in patients anesthetized with isoflurane is A. 5 mLI/ 100 g/min B. 10 mL/IOO g/min C. 18 mL/lOO g/min D. 25 mL/ 100 g/min E. 32 mLl/ IOO g/min
(B) Critical CBF is the CBF below which EEG evidence of cerebral ischemia begins to appear. Critical CBF in patients anesthetized with isoflurane, desflurane, or sevoflurane is approximately 10 mLllOO g/min. In contrast, critical CBF in patients anesthetized with halothane is 18 to 20 mLllOO g/min, and critical CBF in patients anesthetized with enflurane is about 15 mLI 100 g/min. Based on studies that compared the requirement for shunt placement after carotid artery cross-clamping in patients under isoflurane, enflurane, and halothane anesthesia, it appears that isoflurane provides some degree of cerebral protection against incomplete regional cerebral ischemia in humans
When performing an ankle block, which of the following nerves is located by identifying the groove formed proximally by the extensor hallucis longus tendon and the extensor digitorum longus tendon? (A) Saphenous (B) Deep peroneal (C) Posterior tibial (D) Sural
(B) Deep peroneal The deep peroneal nerve passes lateral to the anterior tibial artery, extensor hallucis longus, and tibialis anterior tendons and medial to the extensor digitorum longus tendon. It is easily accessible as it becomes more super cial to travel with the dorsalis pedis artery. It is located by identi ying the groove formed proximally by the extensor hallicus longus tendon and the extensor digitorum longus tendon. T is groove can be identi ed by having the patient extend the great toe, making the extensor hallucis longus tendon more prominent
How is coronary perfusion pressure defined? (A) Difference between mean arterial pressure; central venous pressure (B) Difference between aortic diastolic pressure; left-ventricular end-diastolic pressure (C) Difference between aortic systolic pressure; left-ventricular end-diastolic pressure (D) Difference between systolic pressure; central venous pressure
(B) Difference between aortic diastolic pressure; left-ventricular end-diastolic pressure Left-ventricular perfusion mostly occurs during diastole, when the force of the aortic diastolic pressure drives blood through the coronary arteries, overcoming the intramural left-ventricular end-diastolic pressure. During systole, aortic pressure is unable to overcome the higher left-ventricular systolic pressures to generate flow.
800. A sciatic nerve block is performed in a healthy 26-year-old male patient for bunion surgery. Fifteen milliliters of 1.5% mepivacaine is slowly injected after the landmarks are identified and a paresthesia is elicited in the great toe. In what order would the following nerve fibers be blocked? A. Sympathetic, proprioception, pain, motor B. Sympathetic, pain, proprioception, motor C. Motor, pain, proprioception, sympathetic D. Pain, proprioception, sympathetic, motor E. Pain, proprioception, motor, sympathetic
(B) Differential nerve blockade is a complex process where anatomic and chemical factors determine the susceptibility of fibers to blockade by local anesthetics. Diameter, myelinization, and location within the nerve trunk affect the onset and regression time. In general, the small unmyelinated sympathetic fibers are blocked first followed by unmyelinated C fibers (pain and temp), then small myelinated fibers (proprioception, touch, pressure), and finally the large myelinated fibers (motor).
A sciatic nerve block is performed in a healthy 26-year-old male patient for bunion surgery. Fifteen milliliters of 1.5% mepivacaine is slowly injected after the landmarks are identified and a paresthesia is elicited in the great toe. In what order would the following nerve fibers be blocked? A. Sympathetic, proprioception, pain, motor B. Sympathetic, pain, proprioception, motor C. Motor, pain, proprioception, sympathetic D. Pain, proprioception, sympathetic, motor E. Pain, proprioception, motor, sympathetic
(B) Differential nerve blockade is a complex process where anatomic and chemical factors determine the susceptibility of fibers to blockade by local anesthetics. Diameter, myelinization, and location within the nerve trunk affect the onset and regression time. In general, the small unmyelinated sympathetic fibers are blocked first followed by unmyelinated C fibers (pain and temp), then small myelinated fibers (proprioception, touch, pressure), and finally the large myelinated fibers (motor).
When is body temperature loss the greatest? (A) During the preoperative preparation (B) During the 1st hour in the operating room (C) During the 2nd and 3rd hours in the operating room (D) During the 4th hour in the operating room
(B) During the 1st hour in the operating room The greatest amount of heat loss occurs during the 1st hour in the operating room (0.5-1.5C). The greater temperature decline is gradual and then plateaus.
When is body temperature loss the greatest? (A) During the preoperative preparation (B) During the 1st hour in the operating room (C) During the 2nd and 3rd hours in the operating room (D) During the 4th hour in the operating room
(B) During the 1st hour in the operating room The greatest amount of heat loss occurs during the 1st hour in the operating room (0.51.5C). T erea ter temperature decline is gradual and then plateaus
A 28-year-old gravida I, para 0 parturient with Eisenmenger's syndrome (pulmonary hypertension with an intracardiac right-to-Ieft or bidirectional shunt) is to undergo placement of a lumbar epidural for analgesia during labor. It may be wise to avoid a local anesthetic with epinephrine in this patient because it: A. Raises pulmonary vascular resistance B. Lowers systemic vascular resistance C. Increases heart rate D. Acts as a tocolytic agent E. Causes excessive increases in systolic blood pressure .
(B) Eisenmenger's syndrome may develop in patients with left-to-right intracardiac shunting such as ventricular septal defect, atrial septal defect, or patent ductus arteriosus. In this syndrome, the pulmonary and vascular tone and right ventricular muscle undergo changes in response to the shunt, producing pulmonary hypertension and a change in the direction of the shunt to a right-to-left or bidirectional type with peripheral cyanosis. The maternal mortality rate is 30% to 50%. Approximately 3% of all newborns with congenital heart defects will develop this condition. Because the pulmonary vascular resistance is fixed in these patients, this condition is not amenable to surgical correction; thus, survival beyond age 40 years is uncommon. Any event or drug that increases pulmonary vascular resistance or decreases systemic vascular resistance will worsen the right-to-Ieft shunt, exacerbate peripheral cyanosis, and may precipitate right ventricular heart failure in these patients. Controversy exists regarding pain management for these patients. Many prefer a narcotic-based analgesic (spinal or epidural). Placing an arterial catheter and a pulse oximeter, as well as aggressive treatment of any fall in peripheral vascular resistance, is recommended if a local anesthetic (carefully titrated) is administered centrally. Low-dose epinephrine, which can be used to decrease absorption of local anesthetics, should not be added because it can cause a further decrease in systemic vascular resistance, which will exacerbate the right-to-left shunt.
Intracranial hypertension is defined as a sustained increase in intracranial pressure (ICP) above: A. 5 mm Hg B. 15 mmHg C. 25 mm Hg D. 40 mm Hg E. None of the above
(B) Elevated JCP frequently is the final stage of a pathologic cerebral insult (e.g., head injury, intracranial tumor, subarachnoid hemorrhage, metabolic encephalopathy, or hydrocephalus). The intracranial contents consist of three components: brain parenchyma (80% to 85%), blood (3% to 6%), and csr (5% to 15%). None of these components is compressible; accordingly, an increase in the volume of any of these requires a compensatory decrease in the volume of one or both of the other components to avoid the development of intracranial hypertension. Normal JCP is less than 15 mm Hg. As measured in the supine position, intracranial hypertension is defined as a sustained increase in JCP above 15 to 20 mm Hg
Which act to diminish pain signals? Select (2) two (A) Glutamate (B) Enkephalin (C) Substance P (D) ß-Endorphin
(B) Enkephalin (D) ß-Endorphin Endogenous opioids modulate pain by decreasing severity.
Which of the following properties of epidurally administered local anesthetics determines the extent to which epinephrine will prolong the duration of blockade? A. Molecular weight B. Lipid solubility C. pKa D. Amide versus ester structure E. Concentration
(B) Epinephrine is primarily added to local anesthetics to check for the IV placement of an epidural catheter, to decrease the vascular uptake of local anesthetics, or to increase the intensity and duration of the block. By producing vasoconstriction of the epidural blood vessels, vascular uptake of the local anesthetic is reduced, allowing more of the drug to enter the nervous tissue. The more lipid soluble the local anesthetic, the less effect epinephrine has.
Gas from an N20 compressed-gas cylinder enters the anesthesia machine through a pressure regulator that reduces the pressure to A. 60 psi B. 45 psi C. 30 psi D. 15 psi E. 10 psi
(B) Gas leaving a compressed-gas cylinder is directed through a pressure-reducing valve, which lowers the pressure within the metal tubing of the anesthesia machine to 45 to 55 psi
Gas from an N20 compressed-gas cylinder enters the anesthesia machine through a pressure regulator that reduces the pressure to A. 60 psi B. 45 psi C. 30 psi D. 15 psi E. 10 psi
(B) Gas leaving a compressed-gas cylinder is directed through a pressure-reducing valve, which lowers the pressure within the metal tubing of the anesthesia machine to 45 to 55 psi.
Which of the following is the most useful in improving neurological outcomes after cardiac arrest? A. Steroids B. Hypothermia C. Barbiturates D. Ibuprofen E. Calcium
(B) Global brain ischemia occurs when there is an inadequate supply of oxygen and nutrients to the entire brain. Global ischemia may be stratified into incomplete (e.g., systemic shock with persistent low blood now to the brain) or complete (e.g., cardiac arrest). In contrast, focal brain ischemia occurs when there is ischemia to only a portion of the brain (e.g., classic stroke). Although corticosteroids are thought to possess antioxidant properties, investigators evaluating their effectiveness during cardiac arrest have reported either no improvement or a worsening of neurologic outcome. Worsening of outcome is thought to be due to corticosteroid-induced hyperglycemia. During focal brain ischemia, barbiturates provide neuronal protection by decreasing cerebral metabolism (i.e., EEG activity) and redistributing regional CBF. However, because the EEG becomes isoelectric (i.e., maximal depression of electrical activity and metabolism) within 20 seconds of cardiac arrest and there is no CBr to redistribute, studies demonstrating barbiturate-mediated brain protection during or after cardiac arrest are lacking. Use of ibuprofen for brain protection has not been demonstrated in cardiac arrest patients. During ischemia, calcium accumulates within neurons and contributes to irreversible cell death. Thus, in the setting of a disrupted blood brain barrier, intravenous calcium may worsen postischemic neurologic outcome. Hypothermia, at the time of either focal or global brain ischemia, has consistently been demonstrated to provide brain protection during cardiac arrest. The mechanisms of hypothermia-mediated brain protection are discussed in the following reference
A peribulbar block was performed. There was notable resistance during the injection. The patient becomes agitated and complains of pain. What do you suspect? (A) Retrobulbar hemorrhage (B) Globe puncture (C) Extraocular muscle palsy (D) Intravascular injection
(B) Globe puncture Globe puncture is associated with increased IOP, resistance during injection, patient agitation and pain, and hemorrhage. In a retrobulbar hemorrhage, the eye moves forward. T ere may be subconjunctival bleeding. Extraocular muscle palsy results in diplopia. Intravascular injection o local anesthetic during eye blocks result in seizures
Which of the following characterize A-a nerve fibers? Select (3) three (A) Diameter 0.5-1 µm (B) Heavy myelination (C) Diameter 15-20 µm (D) Motor function (E) Light myelination (F) Pain and temperature
(B) Heavy myelination (C) Diameter 15-20 µm (D) Motor function B fibers are lightly myelinated, 1-4 µm in diameter possessing preganglionic and autonomic function. C fibers are not myelinated, 0.5-1 µm in diameter and are responsible for touch and temperature sensation.
What effect does the lithotomy position have on arterial pressure? (A) Lower than supine position (B) Higher than supine position (C) Lower than trendelenburg (D) Lower than sitting position
(B) Higher than supine position The blood pressure in the lithotomy position remains the same as or higher than the supine position. Autotransfusion from the lower extremities occurs in the lithotomy position. trendelenburg position typically increases blood pressure whereas the sitting position o ten results in a lower blood pressure.
Which of the following are risk factors for postoperative nausea and vomiting? Select (3) three (A) Male (B) History of motion sickness (C) Opioids (D) Strabismus surgery (E) Cataract surgery (F) Hypertension
(B) History of motion sickness (C) Opioids (D) Strabismus surgery Females are more likely to experience PONV than males. General anesthesia and commonly used opioids, volatile agents, and nitrous oxide contribute to PONV. Patients who are hypotensive postoperatively are at risk for PONV. Certain surgeries are linked to PONV including gynecological and urinary procedures, breast and
A 110-kg (242.5-pound), gravida I, para 0 woman has a blood pressure of 180/95 during an office visit at the 18th week of gestation and 170/95 one week later. She has some ankle but no facial edema, and no protein detected in her urine. These findings would be classified as A. Preeclampsia B. Chronic hypertension C. Chronic hypertension with superimposed preeclampsia D. Gestational hypertension E. A normal finding
(B) Hypertension (systolic blood pressure> 140 or an increase >30 mm Hg over baseline; diastolic blood pressure >90 or an increase of 15 mm Hg over baseline) occurs in about 7% of all pregnancies. It is commonly classified by the American College of Obstetricians and Gynecologists as one of four types (preeclampsia-eclampsia, chronic hypertension, chronic hypertension with preeclampsia-eclampsia, or gestational hypertension). Preeclampsia rarely occurs before 24 weeks EGA except in patients with gestational trophoblastic neoplasms (e.g., molar pregnancy) and manifests as a triad of hypertension, generalized edema, and proteinuria. Chronic hypertension is persistent hypertension before, during, and after pregnancy (e.g., >6 weeks postpartum). Some patients develop gestation hypertension, which is an increase in blood pressure without generalized edema or proteinuria, which resolves by 2 to 6 weeks postpartum
By what percentage does cerebral blood flow (CBF) change for each mm Hg increase in Pacó? A. 1% B. 2% C. 7% D. 10% E. 25%
(B) Hyperventilation of the lungs causes constriction of cerebral blood vessels, which reduces global cerebral blood flow (CBF) and cerebral blood volume (CBV). This effect is mediated by changes in the pH induced in the extracellular fluid. In contrast to autoregulation, CÓ reactivity is preserved in most patients with severe brain injury; thus, hyperventilation can rapidly lower intracranial pressure (ICP) through the reduction in CBV. Although the effects of hyperventilation on CBV and ICP are almost immediate, the duration of effect wanes after 6 to 10 hours of hyperventilation and may last up to 24 to 36 hours, because the pH of the extracellular fluid equilibrates to the lower Pacó level. Generally speaking, CBF increases (or decreases) by approximately 2% for each mm Hg increase (or decrease) in Pacó• CBF increases (or decreases) 1 mUIOO g/min per I mm Hg increase (or decrease) in Pacó• Because normal global CBF is 50 mLllOO g/min, a I mL/IOO g/min alteration in CBF represents a 2% change.
Which of the following concentrations of epinephrine corresponds to a I :200,000 mixture? A. 0.5 ug/mL B. 5 ug/mL C. 50 ug/mL D. 0.5 mg/mL E. None of the above
(B) I :200,000 means I g = 1000 mg = 1,000,000 J.lg per 200,000 mL 1,000,000 J.lg .;. 200,000 mL = 5 J.lg/mL Epinephrine is commonly packaged I: 1000 1000 mg per 1,000 mL = I mg/mL I: 10,000 1000 mg per 10,000 mL = 0.1 mg/mL.
A 75-year-old patient with signs and symptoms of a leaking cerebral aneurysm is brought to the emergency room for evaluation. T-wave inversion, a prolongation of the QT interval, and U waves are noted on the preoperative ECG. Appropriate action at this point would be A. Begin infusion of nitroglycerin B. Check serum calcium and potassium C. Administer esmolol D. Place a pulmonary artery catheter E. Delay surgery until myocardial infarction has been ruled out.
(B) In addition to ECG changes (e.g., T-wave inversion, depression of the ST segment, appearance of U waves, prolonged QT interval, and rarely Q waves), abnormal thallium scintigraphy, regional wall-motion abnormalities, and elevated creatine kinase-MB isoenzymes have been reported in patients with subarachnoid hemorrhage (SAH). Although historically considered a functionally insignificant neurogenic phenomena, there is increasing evidence that these changes may be a sign of underlying myocardial ischemia. However, even if myocardial ischemia is present, it seems to have a minimal impact on patient outcome (Le., morbidity and mortality). Because electrolyte abnormalities (e.g., hypokalemia or hypocalcemia) may contribute to the etiology of the ECG changes, it would probably be most appropriate to quantify these electrolytes before initiating other therapies or canceling emergency surgery.
How long after a stroke can anesthesia for surgery be carried out with about the same risk of a perioperative occlusive vascular accident as existed immediately before the previous stroke? A. 1 week B. 6 weeks C. 6 months D. 9 months E. 1 year
(B) In patients who have suffered a cerebral vascular accident as a result of occlusive vascular disease, there is a loss of normal vasomotor responses to changes in Pacó and arterial blood pressure in the areas of ischemia (i.e., vasomotor paralysis) as well as disruption of the blood-brain barrier. Approximately 4 to 6 weeks is required for these changes to stabilize. Therefore, it is recommended that anesthesia for elective nonneurologic surgical procedures be postponed for about 1 month after an occlusive vascular accident to minimize the risk of a subsequent perioperative occlusive vascular accident.
Which initial intervention is correct if pulmonary embolism is suspected? (A) Discontinue intravenous fluids (B) Increase FiÓ (C) Extubate the patient (D) Discontinue inotropic support
(B) Increase FiÓ Increase intravenous fluids, keep the patient intubated, provide inotropic support, and increase FiÓ.
What are the appropriate measures to reduce the amount of oxygen consumed and prolong the duration of your backup oxygen supply when the oxygen supply fails? (A) Turn on the ventilator and ventilate manually through the circle system. (B) Increase oxygen flows to 5 L per minute. (C) Place the patient on pressure control ventilation. (D) Reduce tidal volume and increase respiratory rate on the ventilator.
(B) Increase oxygen flows to 5 L per minute. Most anesthesia machines utilize oxygen as the driving gas to power the ventilator. By reducing resh oxygen ow rates and eliminating the use o the ventilator by allowing the patient to breathe spontaneously or ventilating via the reservoir bag, you will prolong the backup oxygen supply.
What statement is true regarding colloids? (A) Inexpensive (B) Increase plasma volume (C) Used for initial resuscitation (D) Used primarily for extracellular expansion
(B) Increase plasma volume As compared to crystalloids, colloids are expensive and are useful in increasing the plasma volume. Crystalloids are typically used for initial resuscitation and extracellular fluid replacement.
Which nerve block results in the highest blood level o local anesthetic? (A) Sciatic (B) Intercostal (C) Paravertebral (D) Cervical plexus
(B) Intercostal Along with the highest complication rate of nerve blocks, the intercostal block results in the highest blood level of local anesthetic. The anatomy is a vessel-rich area.
Which of the following explains the rapid onset of 2-chloroprocaine when used for epidural anesthesia? (A) It is activated by ester hydrolysis. (B) It is administered in high concentrations. (C) It has high potency and lipid solubility. (D) It has relatively low pKa.
(B) It is administered in high concentrations. 2-chloroprocaine is a rapidly acting local anesthetic despite its slow onset in isolated nerves. Its high pKa of 9 and large charge would normally result in a slow onset of action. It, however, has a low toxicity and, therefore, can be administered in high concentrations of 3%. The resultant large number of molecules results in mass diffusion and therefore quick onset. The onset of local anesthetic in isolated nerves (in vitro) is determined to a large extent by the concentration of lipid soluble (nonionized) agent administered to the nerve to be anesthetized. The relative concentration of nonionized to ionized form present in a particular agent is expressed by its pKa, the pH at which these amounts are equal. Agents which have a pKa closer to physiological pH exist in a nonionized state in larger concentrations, resulting in a faster onset. Reducing the pH of the agent by mixing it with an alkaline solution (sodium bicarbonate) increases the amount of nonionized free base available and thus increases speed of onset. Other characteristics such as ease of diffusion and concentration affect the clinical onset of action.
An adult patient with moderate aortic regurgitation receives a spinal anesthetic. A blood pressure drop to 68/42 is treated with 100 µg of phenylephrine. How will this dose impact the patient's underlying disease state? (A) It will improve the regurgitation. (B) It will exacerbate the regurgitation. (C) It will have no impact on the regurgitation. (D) Phenylephrine is contraindicated in this patient.
(B) It will exacerbate the regurgitation Phenylephrine can be used to treat anesthetic-induced hypotension in a patient with aortic regurgitation but the doses should be small and incremental, that is, 25-50 µg. Larger doses such as 100 µg will increase the systemic vascular resistance and exacerbate the regurgitation.
Which induction agent produces effects desirable for patients with Tetralogy of Fallot? (A) Etomidate (B) Ketamine (C) Midazolam (D) Propofol
(B) Ketamine Tetralogy of Fallot is one of the most common cyanotic congenital heart de ects. It is marked by the following our features: RV outflow tract obstruction, ventricular septal de ect, a rightward aortic deviation, overriding the VSD and RVH. Due to the right ventricular out ow obstruction and coexisting VSD, patients with Tetralogy of Fallot shunt blood from right to left, ejecting deoxygenated right ventricular blood mixed with oxygenated blood into the aorta.
Where is local anesthetic injected in a radial block at the wrist? (A) Medial to the ulnar artery at the wrist (B) Lateral to the radial artery at the wrist (C) Medial to the radial artery at the wrist (D) Lateral to the ulnar artery at the wrist
(B) Lateral to the radial artery at the wrist The radial nerve block at the wrist requires injecting 3-5 mL of local anesthetic lateral to the radial artery. The ulnar nerve block requires injecting local anesthetic medial to the ulnar artery at the wrist.
Which cardiac variable leads to heart failure resulting from obesity? (A) Decreased preload (B) Left ventricular systolic dysfunction (C) Decreased aterload (D) Hypotension
(B) Left ventricular systolic dysfunction Volume overload and vascular stiffness result from obesity. Increased preload, increased afterload, and hypertension lead to left ventricular systolic dysfunction
Magnesium sulfate (MgS04) is used as an' anticonvulsant in patients with preeclampsia and may produce any of the following effects EXCEPT: A. Sedation B. Analgesia C. Hypotension D. Respiratory paralysis E. Tocolysis
(B) Magnesium sulfate is used either as a tocolytic agent to prevent premature labor or to prevent seizures in parturients with preeclampsia. Magnesium sulfate has many other pharmacologic properties, including sedation, hypotension, loss of deep tendon reflexes (10 mEq/L), respiratory paralysis (15 mEqlL), and cardiac arrest (>25 mEqlL). Magnesium does not, however, have any analgesic properties. 1 mEq/L = 1.2 mg/dL
What is the goal of hemodynamic management for the patient with mitral stenosis? (A) Avoiding bradycardia (B) Maintenance of sinus rhythm (C) Aggressive volume resuscitation (D) Inotropic support with phosphodiesterase inhibitors
(B) Maintenance of sinus rhythm The patient with mitral stenosis has impaired left ventricular filling. Sinus rhythm atrial contractions help optimize left ventricular filling. Maintenance of sinus rhythm with a normal rate should be a perioperative goal. Tachycardia should be avoided as it will decrease diastolic left ventricular lling time and left ventricular end diastolic pressure. Mitral stenosis is associated with left atrial and pulmonary hypertension due to the stenotic transvalvular pressure gradient. Phosphodiesterase inhibitors cause vasodilation and increase left ventricular emptying which will result in severe hypotension. Non-inotropic vasopressors, such as vasopressin or phenylephrine, should be used in the presence of hypotension.
What is the primary determinant of cerebral perfusion? (A) Position (B) Mean arterial pressure (C) Intracranial pressure (D) Central venous pressure
(B) Mean arterial pressure All of these can have some impact but the primary variable is mean arterial pressure.
The mean arterial pressure in a patient with a blood pressure of 180/60 mm Hg is : A. 90mmHg B. 100 mm Hg C. 110 mm Hg D. 120mm Hg E. 130 mm Hg
(B) Mean arterial pressure can be calculated using the following formula: MAP = BPo + 113 (BPs - BPo) where MAP (mm Hg) is the mean arterial pressure, BPo (mm Hg) is the diastolic blood pressure, and BPs (mm Hg) is the systolic blood pressure
To avoid cardiac microshock, total leakage current for catheters or electrodes placed close to the heart must be less than A. 1 microamp B. 10 microamps C. 20 microamps D. 50 microamps E. 1 Milliamp
(B) Microshock occurs when a small amOUIll of electrical power is delivered directly to the heart. The minimum electrical current required to cause ventricular fibrillation of the human heart is approximately 50 J.lA. To provide a margin of safety, 10 J.lA is the maximum permissible total leakage current allowed through electrodes or catheters that contact the heart.
The patient weighs 120 kg. The Ideal Body Weight is 60 kg. What is the patient's classification? (A) Obese (B) Morbidly obese (C) Overweight (D) Moderate obesity
(B) Morbidly obese Morbid obesity is twice the ideal body weight. Obesity re ects 20% over the ideal body weight.
What factors are associated with hypotension in the Post Anesthesia Care Unit? Select (2) two (A) Hypervolemia (B) Nausea (C) Arrhythmias (D) Pain (E) Shivering
(B) Nausea (C) Arrhythmias The main cause of hypotension the PACU is hypovolemia. Hypertension in the PACU reflects pain ul stimulation (surgical, intubation, bladder distention) and shivering.
Which of the following agents will cause the greatest decreased afterload? (A) Verapamil (B) Nicardipine (C) Metoprolol (D) Nitroglycerine
(B) Nicardipine All of the agents mentioned have an afterload decreasing effect. Nicardipine, however, is a calcium calcium-channel blocking agents which is very selective for vascular smooth muscle. Verapamil is a calcium-channel blocker more selective for cardiac than vascular smooth muscle. Nitroglycerine is a nitrate that causes arterial and venodilation. The dilation from nitroglycerine is much more pronounced on venous vessels. Metoprolol, a beta blocker, will have minimal to no effect on afterload. From the list, Nicardipine causes the most arterial vasodilation.
What are the three most common used pharmacological agents or treating ischemic heart disease? (A) Nitrates, alpha blockers, and ACE-inhibitors. (B) Nitrates, beta-blockers, and calcium channel blockers. (C) Beta-blockers, calcium channel blockers, and ACE-inhibitors. (D) Calcium channel blockers, nitrates, and ARB.
(B) Nitrates, beta-blockers, and calcium channel blockers. Calcium channel blockers, nitrates, and ARBs Rationale: Nitrates, beta-blockers, and calcium channel blockers are the most commonly used pharmacological agents or treating ischemic heart disease.
The patient is scheduled for a tympanoplasty. Which inhalational agent will you avoid? (A) Sevoflurane (B) Nitrous oxide (C) Desflurane (D) Isoflurane
(B) Nitrous oxide When using nitrous oxide, air-filled cavities expand. The blood-gas partition coef cient o nitrous oxide is 0.46. T e rapid movement of gas into air- lled cavities is 34 times greater than nitrogen. In this case, the middle ear is subject to increased pressures.
Normal global CBP is A. 25 mUI00 g1min B. 50 mLll 00 g1min C. 75 mLllOO g1min D. 100 mLll 00 g1min E. 150 mLll 00 g/min
(B) Normal global CBF is approximately 45 to 55 mLIl00 glmin. Cortical CBF (gray matter) is approximately 75 to 80 mLllOO g/min and subcortical CBF (mostly white matter) is approximately 20 mLll 00 glmin. Factors that regulate CBF include Pacó, Páo, CMR, cerebral perfusion pressure, autoregulation, and the autonomic nervous system.
A 95-year-old woman has persistent and prolonged thoracic pain after a herpes zoster infection. Which of the treatments below would be the LEAST efficacious in the treatment of her pain? A. Oral amitriptyline B. Oral c1onidine C. Topical capsaicin ointment D. Transcutaneous electrical nerve stimulation E. Topical lidocaine patch
(B) Oral c1onidine Postherpetic neuralgia is defined as pain persisting beyond the healing of the herpes zoster lesions. The incidence of postherpetic neuralgia increases with age and occurs in 20% to 50% of patients older than 50 years and greater than 50% in patients older than 80 years. Treatment of established postherpetic neuralgia has been shown to be resistant to interventions and thus can be difficult. However, proven therapies include tricyclic antidepressants, anticonvulsants, topical local anesthetics, and topical capsaicin. Injection therapies may be helpful, but they are most useful during the more acute stages of the disease rather than during the late chronic stages. Oral clonidine, which is used to treat hypertension and opioid withdrawal, has not been shown to be an effective treatment for postherpetic neuralgia.
When is the fetus most susceptible to the effects of teratogenic agents? A. 1 to 2 weeks of gestation B. 3 to 8 weeks of gestation C. 9 to 14 weeks of gestation D. 15 to 20 weeks of gestation E. Greater than 20 weeks of gestation
(B) Organogenesis occurs between the 15th to 56th days (3 to 8 weeks) of gestation in humans and is the time during which the fetus is most susceptible to teratogenic agents. There is no conclusive evidence to implicate any local, IV induction agents or volatile anesthetic agents in the causation of congenital anomalies.
A 58-year-old patient has severe shortness of breath and "wheezing." On examination, the patient has inspiratory and expiratory stridor. Further evaluation reveals marked extrinsic compression of the proximal trachea by a tumor. The type of airflow at the point of obstruction within the trachea is A. Laminar flow B. Orifice flow C. Undulant flow D. Stenotic flow E. None of the above
(B) Orifice flow occurs when gas flows through a region of severe constriction such as described in this question. Orifice now is a special case of turbulent gas fl ow where the diameter of the tube is considerably larger than its length (e.g., in the larynx). Laminar fl ow occurs when gas fl ows down parallel-sided tubes at a rate less than critical velocity. When the gas flow exceeds the critical velocity, it becomes turbulent.
A 58-year-old patient has severe shortness of breath and "wheezing." On examination, the patient has inspiratory and expiratory stridor. Further evaluation reveals marked extrinsic compression of the proximal trachea by a tumor. The type of airflow at the point of obstruction within the trachea is A. Laminar flow B. Orifice flow C. Undulant flow D. Stenotic flow E. None of the above
(B) Orifice flow occurs when gas flows through a region of severe constriction such as described in this question. Orifice now is a special case of turbulent gas flow where the diameter of the tube is considerably larger than its length (e.g., in the larynx). Laminar fl ow occurs when gas flows down parallel-sided tubes at a rate less than critical velocity. When the gas flow exceeds the critical velocity, it becomes turbulent.
A patient's serum potassium level is 7.2 mEq/L. In which sequential order will cardiac manifestations of hyperkalemia progress? (A) Peaked T waves, loss of P wave, widened QRS complex, sine wave (B) Peaked T waves, widened QRS complex, loss of P wave, sine wave (C) Loss of R-wave amplitude, peaked T waves, widened QRS complex, sine wave (D) Prolonged PR interval, peaked T waves, widened QRS complex, asystole
(B) Peaked T waves, widened QRS complex, loss of P wave, sine wave ECG changes associated with severe hyperkalemia characteristically progress sequentially in the Following order: First, peaked T waves, next a widening of the QRS complex, followed by a progression of the P-R interval, then a loss of P wave, then a loss of R wave amplitude, S -segment depression (sometimes elevation), and, nally, a sine wave that will ultimately change into ventricular fibrillation and asystole
In a 70-kg patient, 1 unit of platelet concentrate should increase the platelet count by A. 2000 to 5000/mm3 B. 5000 to 10,000/mm3 C. 15,000 to 20,000/mm3 D. 20,000 to 25,000/mm3 E. Greater than 25,000/mm3
(B) Platelet count is increased about 5000 to 10,000/mm3 per unit of platelet concentrate in the typical 70-kg patient. Each unit contains greater than 5.5 x 1010 platelets
The common element thought to be present in every case of cauda equina syndrome after continuous spinal anesthesia is A. Use of microcatheter B. Maldistribution of local anesthetic C. Administration of lidocaine D. Addition of epinephrine E. Hyperbaricity
(B) Pooling of local anesthetics in dependent areas of the spine within the subarachnoid space has been identified as the causative factor in cases of cauda equina syndrome. Microlumen catheters may enhance the nonuniform distribution of solutions within the intrathecal space, but cauda equina syndrome has been associated with the use of larger catheters as well .
The common element thought to be present in every case of cauda equina syndrome after continuous spinal anesthesia is A. Use of microcatheter B. Maldistribution of local anesthetic C.Administration of lidocaine D. Addition of epinephrine E. Hyperbaricity
(B) Pooling of local anesthetics in dependent areas of the spine within the subarachnoid space has been identified as the causative factor in cases of cauda equina syndrome. Microlumen catheters may enhance the nonuniform distribution of solutions within the intrathecal space, but cauda equina syndrome has been associated with the use of larger catheters as well.
To supplement a brachial plexus block to cover the anterior shoulder, the cervical plexus can be blocked at which of the following locations? (A) Anterior to the mastoid process (B) Posterior border of the sternocleidomastoid (C) At the interscalene groove (D) Posterior to the angle of the mandible
(B) Posterior border of the sternocleidomastoid. Areas of the anterior shoulder are supplied by the superfcial cervical plexus, which passes through the platysma at the posterior sternocleidomastoid (SCM) giving of superfcial and deep branches. The superfcial cervical plexus innervates the skin and the super facial structures of the head, neck, and shoulders. It lies in the plane just behind the SCM and can be blocked with a field block at that location.
A 95-year-old woman has persistent and prolonged thoracic pain after a herpes zoster infection. Which of the treatments below would be the LEAST efficacious in the treatment of her pain? A. Oral amitriptyline B. Oral clonidine C. Topical capsaicin ointment D. Transcutaneous electrical nerve stimulation E. Topical lidocaine patch
(B) Postherpetic neuralgia is defined as pain persisting beyond the healing of the herpes zoster lesions. The incidence of postherpetic neuralgia increases with age and occurs in 20% to 50% of patients older than 50 years and greater than 50% in patients older than 80 years. Treatment of established postherpetic neuralgia has been shown to be resistant to interventions and thus can be difficult. However, proven therapies include tricyclic antidepressants, anticonvulsants, topical local anesthetics, and topical capsaicin. Injection therapies may be helpful, but they are most useful during the more acute stages of the disease rather than during the late chronic stages. Oral clonidine, which is used to treat hypertension and opioid withdrawal, has not been shown to be an effective treatment for postherpetic neuralgia.
What percentage of all pregnancies are affected by preeclampsia? A. 2% B. 7% C. 12% D. 17% E. 22%
(B) Preeclampsia is a disorder that rarely occurs before the 24th week of gestation (unless a hydatidiform mole is present) and is characterized by the triad of hypertension, generalized edema, and proteinuria. It occurs with an overall incidence of approximately 7% and occurs most frequently in primigravidas. The incidence of preeclampsia is significantly higher in parturients with a hydatidi form mole, multiple gestations. obesity. polyhydramnios, or diabetes. Mothers with preeclampsia during their first pregnancy have a 33% chance of having preeclampsia in subsequent pregnancies. Preeclampsia can progress to eclampsia (preeclampsia accompanied by a seizure not related to other conditions). Sixty percent of eclamptic cases precede delivery. Of the rest, most occur within the first 24 hours after delivery. Approximately 5% of untreated parturients with preeclampsia will develop eclampsia
Which topical local anesthetics may cause methemoglobinemia? Select (2) two (A) Bupivacaine (B) Prilocaine (C) Mepivacaine (D) Benzocaine (E) Procaine
(B) Prilocaine (D) Benzocaine Clinically significant methemoglobinemia may result when using topical prilocaine and benzocaine. Bupivacaine, mepivacaine, and procaine are not topical anesthetics.
The LEAST reliable site for central temperature monitoring is the A. Pulmonary artery B. Skin on forehead C. Distal third of the esophagus D. Nasopharynx E. Tympanic membrane
(B) Pulmonary artery, esophageal, axillary, nasopharyngeal, and tympanic membrane temperature measurements correlate with central temperature in patients undergoing noncardiac surgery. Skin temperature does not reflect central temperature and does not warn adequately of malignant hyperthermia or excessive hypothermia.
What results when placing a femoral block with nerve stimulation? (A) Thigh adduction (B) Quadriceps twitch (C) Sciatic nerve block posterior approach (D) Sciatic nerve block anterior approach
(B) Quadriceps twitch Thigh adduction occurs with an obturator block. T e posterior approach to sciatic nerve block results in a gluteal muscle twitch and plantar flexion or dorsiflexion. Foot inversion or plantar exion is elicited when the anterior approach is used.
While performing an axillary block utilizing the transarterial approach, a paresthesia is elicited a ter passing through the artery. Which nerve is posterior to the artery? (A) Ulnar (B) Radial (C) Median (D) Intercostobrachial
(B) Radial The radial nerve lies posterior to the axillary artery, and it is anesthetized when injecting posterior to the artery.
Following placement of a stellate ganglion block the patient becomes hoarse. What has occurred? (A) Phrenic nerve block (B) Recurrent laryngeal nerve block (C) Subdural injection (D) Pneumothorax
(B) Recurrent laryngeal nerve block Unilateral recurrent laryngeal nerve block results in hoarseness.
Side effects of ritodrine include all of the following EXCEPT A. Tachycardia B. Hypertension C. Hyperglycemia D. Pulmonary edema E. Hypokalemia
(B) Ritodrine and terbutaline are ~-adrenergic agonists with tocolytic properties. Side effects are similar to those of other ~-adrenergic drugs and include tachycardia, hypotension, hyperglycemia, pulmonary edema, and hypokalemia.
A 14-year-old girl with severe scoliosis is to undergo spine surgery. Anesthesia is maintained with fentanyl, N20 50% in Ó, vecuronium, and isoflurane. Neurologic function of the spinal cord is monitored by SSEPs. In reference to the SSEP waveform, ischemia would be manifested as A. Increased amplitude and increased latency B. Decreased amplitude and increased latency C. Decreased amplitude and decreased latency D. Increased amplitude and decreased latency E. Increased amplitude and no change in latency
(B) SSEPs are composed of negative and positive voltage deflections with specific latencies and amplitudes. Baseline values for latency and amplitude must be determined for each patient at the onset of surgery because the characteristics of SSEP waveforms change with recording circumstances (e.g., the latency becomes greater and the amplitude becomes smaller as the distance between the neural generator and the recording electrode is increased). A decrease in the amplitude or an increase in the latency in the SSEP waveform from baseline values may suggest ischemia along the sensory pathway in question.
What are mechanisms of action for duloxetine? Select (2) two (A) Monoamine oxidase inhibition (B) Serotonin reuptake inhibition (C) α2 receptor agonist effect (D) Norepinephrine reuptake inhibition
(B) Serotonin reuptake inhibition (D) Norepinephrine reuptake inhibition This drug inhibits serotonin and norepinephrine reuptake.
35. Which agent results in an increased heart rate during inhalational anesthesia? (A) Desflurane 0.75 MAC (B) Sevoflurane >1.5 MAC (C) Desflurane 0.5 MAC (D) Sevoflurane <1 MAC
(B) Sevoflurane >1.5 MAC Heart rate increases linearly with dose. There is a minimal increase in heart rate with desflurane when using less than 1 MAC. The heart rate increases with Sevofurane at 1.5 MAC or greater.
What is the surface landmark oF the fourth cervical cutaneous dermatome? (A) Anterior neck (B) Shoulder (C) Biceps (D) Xiphoid
(B) Shoulder Referred diaphragm pain occurs in the shoulder due to innervation at C3-C5.
In what position is a venous air embolism (VAE) most likely to occur? (A) Lateral decubitus (B) Sitting (C) Prone (D) Trendelenburg
(B) Sitting In surgeries above the level o the heart, the risk of VAE exists. Any position where the surgery is above the level of the heart predisposes the patient to VAE. Open sinuses allow for the entrainment of air.
Which statement about stored blood is correct? (A) The amount of extracellular potassium transfused per unit is 10 mEq per unit. (B) Stored blood typically has a pH < 7.45. (C) Stored blood contains factors V and VIII. (D) Stored blood can contain as much as 150 mEq/L of potassium.
(B) Stored blood typically has a pH < 7.45. The amount of extracellular potassium transfused per unit is usually < 4 mEq per unit. Stored blood is acidic due to the citric acid anticoagulant and accumulation of lactic acid. Stored blood does not contain actors V and VIII and stored blood can contain as much as 17 mEq/L of potassium.
Which nerve is at greatest risk for injury during thyroid surgery? (A) Recurrent laryngeal nerve (B) Superior laryngeal nerve (C) Facial nerve (D) Glossopharyngeal nerve
(B) Superior laryngeal nerve The superior laryngeal nerve injury is greatest or surgery involving the anterior neck.
A 55-year-old business executive is scheduled for colonoscopy and polypectomy under general anesthesia. A bruit is auscultated over the right carotid artery on physical examination. The patient is otherwise healthy. Which of the following would be the most appropriate course of action? A. Cancel surgery and obtain a carotid angiogram B. Cancel surgery and obtain Doppler ultrasound carotid blood flow studies C. Cancel surgery and consult a neurologist D. Proceed with surgery and obtain a carotid angiogram postoperatively. E. Proceed with surgery
(B) Surgical treatment of carotid artery stenosis greatly decreases the risk of stroke, especially in men with a stenosis diameter greater than 70%. Studies show a high rate of stroke in patients with asymptomatic carotid stenosis greater than 75%; and 80% of carotid atherothrombotic strokes occur without warning. The National Institutes of Health now recommends carotid endarterectomy in asymptomatic patients with a greater than 60% reduction in carotid artery diameter. Doppler studies also show that 70% to 75% stenosis represents the point at which a pressure drop across the stenosis is likely to occur. Thus if collateral circulation is not adequate, low-flow transient ischemic attacks and infarcts occur. It would be considered most appropriate to further study the patient's carotid artery disease before proceeding with an elective case.
The device on anesthesia machines that most reliably detects delivery of hypoxic gas mixtures is the A. Fail-safe valve B. 02 analyzer C. Second-stage 02 pressure regulator D. Proportion-limiting control system E. Diameter-index safety system.
(B) The 02 analyzer is the last line of defense against inadvertent delivery of hypoxic gas mixtures. It should be located in the inspiratory (not expiratory) limb of the patient breathing circuit to provide maximum safety. Because the 02 concentration in the fresh-gas supply line may be different from that of the patient breathing circuit, the 02 analyzer should not be located in the fresh-gas supply line.
A 1000-g, 27-week EGA boy is born with a heart rate of 85. He is completely limp, shows no respiratory effort, and has no initial response to stimulation. He is totally cyanotic. The umbilical cord has only two vessels. The I-minute Apgar score would be A. 0 B. 1 C. 2 D. 3 E. 4
(B) The Apgar score is a subjective scoring system used 10 evaluate the newborn and is commonly performed I and S minutes after delivery. If the score is less than 7, then the scoring is repeated 10, IS, and 20 minutes after delivery. A value of 0, I, or 2 is given to each of five signs (heart rate, respiratory effort, reflex irritability, muscle tone, and color) and totaled.
Which section of the brachial plexus is blocked with a supraclavicular block? A. Roots B. Trunks C. Divisions D. Cords E. Branches
(B) The advantages of the supraclavicular block are fourfold. The plexus is blocked where it is most compact, namely at the level of the trunks. A small volume of anesthetic is required and no part of the plexus is spared as with axiilary or interscalene block. The block can be performed with the arm in any position
Under maximum stress, how much cortisol is produced per day? A. 50 mg B. 150 mg C. 250 mg D. 350 mg E. Up to 1000 mg
(B) The daily production of cortisol under normal circumstances is approximately 20 mg. Under maximum stress, daily cortisol production can increase to 150 mg.
Inhalation of CÓ increases VE by: A. 0.5 L/min/mm Hg increase in Pacó B. 1 to 3 L/min/mm Hg increase in Pacó C. 3 to 5 L/min/mm Hg increase in Pacó D. 5 to 10 L/min/mm Hg increase in Pacó E. 10 to 20 L/min/mm Hg increase in Pacó
(B) The degree of ventilatory depression caused by volatile anesthetics can be assessed by measuring resting Pacó, the ventilatory response to hypercarbia, and the ventilatory response to hypoxemia. Of these techniques, the resting Pacó is the most frequently used index. However, measuring the effects of increased Pacó on ventilation is the most sensitive method of quantifying the effects of drugs on ventilation. In awake unanesthetized humans, inhalation of CÓ increases minute ventilation (VE) by approximately 1 to 3 L/min/mm Hg increase in Pacó• Using this technique, halothane, isoflurane, enflurane, and N20 cause a dose-dependent depression of the ventilation.
Inhalation of CÓ increases VE (minute ventilation) by A. 0.5 Uminlmm Hg increase in Pacó B. 1 to 3 Uminlmm Hg increase in Pacó C. 3 to 5 Uminlmm Hg increase in Pacó D. 5 to 10 Uminlmm Hg increase in Pacó E. 10 to 20 Uminlmm Hg increase in Pacó
(B) The degree of ventilatory depression caused by volatile anesthetics can be assessed by measuring resting Pacó, the ventilatory response to hypercarbia, and the ventilatory response to hypoxemia. Of these techniques, the resting Pacó is the most frequently used index. However, measuring the effects of increased Pacó on ventilation is the most sensitive method of quantifying the effects of drugs on ventilation. In awake unanesthetized humans, inhalation of CÓ increases minute ventilation (VE) by approximately 1 to 3 L/minlmm Hg increase in Pacó• Using this technique, halothane, isoflurane, enflurane, and N20 cause a dose-dependent depression of the ventilation.
Which of the following systems prevents attachment of gas-administering equipment to the wrong type of gas line? A. Pin-index safety system B. Diameter-index safety system C. Fail-safe system D. Proportion-limiting control system E. None of the above
(B) The diameter-index safety system prevents incorrect connections of medical gas lines. This system consists of two concentric and specific bores in the body of one connection, which correspond to two concentric and specific shoulders on the nipple of the other connection.
A 19-year-old woman is undergoing surgery for a Harrington rod placement. General anesthesia is administered with desflurane, nitrous oxide, and fentanyl. After completion of spinal instrumentation, a wake-up test is undertaken. Four thumb twitches are present when the nerve stimulator attached to the ulnar nerve is activated. The volatile anesthetic and nitrous oxide have been discontinued for 10 minutes when the patient is asked to move her hands and feet. After repeated commands, the patient still does not move her hands or feet. The most appropriate intervention at this time would be. A. 3 mg neostigmine plus 0.6 mg glycopyrrolate IV. B. 20 ug naloxone IV. C. 0.1 mg flumazenil IV. D. Institute SSEP monitoring. E. Reduce the distraction on the rod..
(B) The differential diagnosis for a nonmoving patient during a wake-up test includes presence of neuromuscular blockade, inadequate volatile or nitrous oxide washout, or presence of opiates or sedative hypnotic-type drugs. There are also a few other extremely rare central causes such as stroke. Because gross neuromuscular blockade has worn off in this patient and the volatile anesthetic and nitrous oxide have largely been washed out, a trial of naloxone would not be unreasonable. An initial small dose (e.g., 20 ug) may be all that is needed to reverse the effects of the fentanyl. If this dose is not effective, it should be repeated.
The leading cause of maternal death in the United States is: A. General anesthesia (failed intubation or aspiration) B. Hemorrhage C. Pulmonary embolism D. Pregnancy-induced hypertension E. Infection.
(B) The leading cause of maternal death in the United States is hemorrhage (29%). Next is pulmonary embolism (20%), pregnancy-induced hypertension (18%), infection (13%), and cardiomyopathy (6%). Anesthesia is involved in only 3% of maternal deaths. Most of these anesthetic-related deaths are due to general anesthetic complications such as aspiration of gastric contents or failure to intubate and adequately ventilate the patient.
A 75-year-old patient with chronic obstructive pulmonary disease is ventilated with a mixture of 50% oxygen with 50% helium. Isoflurane 2% is added to this mixture. What effect will helium have on the mass spectrometer reading of the isoflurane concentration? A. The mass spectrometer will give a slightly increased false value B. The mass spectrometer will give a false value equal to double the isoflurane concentration C. The mass spectrometer will give the correct value D. The mass spectrometer will give a wrong value equal to half the isoflurane concentration E. The mass spectrometer will give an erroneous value slightly less than the correct value of isoflurane.
(B) The mass spectrometer functions by separating the components of a stream of charged particles into a spectrum based on their mass-to-charge ratio. The amount of each ion at specific mass-to-charge ratios is then determined and expressed as the fractional composition of the original gas mixture. The charged particles are created and manipulated in a high vacuum to avoid interference by outside air and minimize random collisions among the ions and residual gases. An erroneous reading will be displayed by the mass spectrometer when a gas that is not detected by the collector plate system is present in the gas mixture to be analyzed. Helium, which has a mass charge ratio of 4, is not detected by standard mass spectrometers. Consequently, the standard gases (Le., halothane, enflurane, isoflurane, oxygen, nitrous oxide, nitrogen, and carbon dioxide) will be summed to 100% as if helium were not present. All readings would be approximately twice their real values in the original gas mixture in the presence of 50% helium.
The half-life of carboxyhemoglobin in a patient breathing 100% 02 , is A. 5 minutes B. I hour C. 2 hours D. 4 hours E. 12 hours
(B) The most frequent immediate cause of death from fires is carbon monoxide toxicity. Carbon monoxide is a colorless, odorless gas that exerts its adverse effects by decreasing 02 delivery to peripheral tissues. This is accomplished by two mechanisms. First, because the affinity of carbon monoxide for the 02-binding sites on hemoglobin is 240 times that of 02' Ó is readily displaced from hemoglobin. Thus, 02 content is reduced. Second, carbon monoxide causes a leftward shift of the oxyhemoglobin dissociation curve, which increases the affinity of hemoglobin for 02 at peripheral tissues. Treatment of carbon monoxide toxicity is administration of 100% 02' Breathing 100% 02 decreases the half-time of carboxyhemoglobin from 250 minutes to approximately 50 minutes
A 100-kg male patient has a measured serum sodium concentration of 105 mEq/L. How much sodium would be needed to bring the serum sodium to 120 mEq/L? A. 600 mEq B. 900 mEq C. 1200 mEq D. 2400 mEq E. 3600 mEq
(B) The normal serum sodium concentration is 135 to 145 mEq/L. Hyponatremia occurs when the serum level is less than 135 mEq/L. Clinical symptoms correspond not only to the level of hyponatremia but also to rapidity of the fall in sodium levels. Hyponatremia is most commonly not a deficiency in total body sodium but rather is an excess of total body water (e.g., absorption of irrigating fluids as seen in TURP syndrome, syndrome of inappropriate antidiuretic hormone secretion [SIADH]). It can also be caused by an excessive loss of sodium as seen in severe sweating, vomiting, diarrhea, bums, and the use of diuretics. With acute falls in serum sodium, neurologic symptoms (confusion, restlessness, drowsiness, seizures, coma) resulting from cerebral edema can be seen at serum levels below 120 mEq/ L. Cardiac symptoms (ventricular tachycardia, ventricular fibrillation) can be seen at levels below 100 mEq/L. Therapy for severe hyponatremia includes water restriction, loop diuretics, and at times the administration of hypertonic saline (3% NaCl). The dose of sodium needed for correction can be calculated by multiplying the total body water (TBW = Body weight x 0.6) times the increase in sodium desired, i.e.,
A 62-year-old patient scheduled for elective repair of an abdominal aortic aneurysm develops a wide complex tachycardia (heart rate 150) during induction of anesthesia. Blood pressure is 110/78. Which of the following drugs would be most useful in the management of this dysrhythmia? A. Lidocaine, 100 mg IV B. Amiodarone, 150 mg IV over 10 minutes C. Adenosine, 6 mg rapidly over 3 seconds D. Verapamil, 5 to 10 mg IV E. Esmolol, 35 mg IV
(B) The patient described in this question has a wide complex tachycardia of undetermined origin. Differentiation of a ventricular from a supraventricular etiology is useful in determining the most efficacious therapy. A heart rate of 150/min could represent ventricular tachycardia (usual range 150 to 250), paroxysmal supraventricular tachycardia (also has a range of 150 to 250/min), or atrial flutter (rate of 150/min is common 2: 1 heart block). Without additional history or information, this rhythm should be treated as "wide complex tachycardia" of unknown origin. According to the 2000 Advanced Cardiac Life Support (ACLS) guidelines, therapy could include amiodarone, procainamide, or DC cardioversion. Because it is possible that this rhythm could be true ventricular tachycardia, use of adenosine for wide complex tachycardia of unknown origin is controversial and is discouraged. Adenosine should only be used when the tachycardia is strongly suspected to be supraventricular in origin. Because the rhythm could be a paroxysmal supraventricular tachycardia or atrial flutter with heart block, lidocaine would not be a useful therapy. Ibutilide is used to treat new-onset atrial fibrillation or atrial flutter.
A 69-year-old man with a history of diabetes mellitus and chronic renal failure is to undergo placement of a dialysis fistula under regional anesthesia. During needle manipulation for a supraclavicular brachial plexus block, the patient begins to cough and complain of chest pain and shortness of breath. The most likely diagnosis is A. Angina B. Pneumothorax C. Phrenic nerve irritation D. Intravascular injection of local anesthetic E. Intrathecal injection of local anesthetic
(B) The risk of pneumothorax is a significant limitation for supraclavicular brachial plexus blocks. Furthermore, the technique is difficult to teach and describe. For these reasons, this block should not be performed in patients in whom a pneumothorax or phrenic nerve block would result in significant dyspnea or respiratory distress. A pneumothorax should be considered if the patient begins to complain of chest pain or shortness of breath or begins to cough during placement of supraclavicular brachial plexus block.
An analgesic effect similar to the epidural administration of 10 mg of morphine could be achieved by which dose of intrathecal morphine? A. 0.1 mg B. 1 mg C. 5mg D. 10 mg E. There is no correlation
(B) The site of action of spinally administered opiates is the substantia gelatinosa of the spinal cord. Epidural administration is complicated by factors related to dural penetration, absorption in fat, and systemic uptake; therefore, the quantity of intrathecally administered opioid required to achieve effective analgesia is typically much smaller. The ratio of epidural to intrathecal dose of morphine is approximately 10: 1. Morphine is typically given in doses of 3 to 10 mg in the lumbar epidural space. Intrathecal morphine dosage is 0.2 to 1.0 mg. Onset time for epidural administration is 30 to 60 minutes with a peak effect in 90 to 120 minutes. Onset time for intrathecal administration is shorter than epidural administration. Duration of 12 to 24 hours of analgesic effect can be expected by either route.
Which of the following nerves is located immediately lateral to the trachea? A. Vagus B. Recurrent laryngeal C. Phrenic D. Long thoracic E. Spinal accessory
(B) The structures in the neck from medial to lateral are the recurrent laryngeal nerve, carotid artery, vagus nerve, internal jugular vein, and phrenic nerve.
A lumbar epidural catheter is placed in a healthy 23-year-old gravida 1, para 0 parturient for an elective cesarean section. Twenty-five minutes after the full dose of local anesthetic is administered, the patient states that she has difficulty breathing through her nose. The most likely explanation for this is A. A total spinal from inadvertent subarachnoid injection of local anesthetic. B. A total sympathectomy and nasal congestion from a high level of blockade. C. Volume overload D. Amniotic fluid embolism E. Intravascular injection of local anesthetic
(B) The sympathetic nerve fibers exit the spinal cord through TI-L2. A high spinal or high epidural can block all of the sympathetic fibers, causing hypotension, bradycardia, and venodilation. Venodilation of the veins in the nasal mucosa causes nasal stuffiness and swelling. Because this patient can speak, the patient does not have a "total spinal." Acute volume overload, amniotic fluid embolism (see explanation to question 686), and i11lravascular injection of local anesthetic do not present with nasal stuffiness.
What is the P 50 of fetal hemoglobin at term? A. 15 B. 20 C. 27 D. 30 E. 37
(B) The term P 50 denotes the blood oxygen tension (Páo) that produces 50% saturation of erythrocyte hemoglobin. The P50 value of fetal blood (75% to 85% of fetal blood is hemoglobin F) is around 19 to 21 mm Hg versus the adult value of 27 mm Hg. Thus, fetal hemoglobin has a higher affinity for oxygen than does maternal hemoglobin
Which of the following characteristics of volatile anesthetics is necessary for calculation of the time constant? A. Blood/gas partition coefficient B. Brain/blood partition coefficient C. Oil/gas partition coefficient D. Minimum alveolar concentration E. Saturated vapor pressure
(B) The time constant is defined as capacity divided by now. The time constant for a volatile anesthetic is determined by the capacity of a tissue to hold the anesthetic relative to the tissue blood now. The capacity of a tissue to hold a volatile anesthetic depends both on the size of the tissue and on the affinity of the tissue for the anesthetic. The brain time constant of a volatile anesthetic can be estimated by doubling the brain/blood partition coefficient for the volatile anesthetic. For example, the time constant of halothane (brain/blood partition coefficient of 2.6) for the brain (mass of approximately 1500 g blood now of 750 mLlmin) is approximately 5.2 minutes.
Which of the following techniques is LEAST effective in a treatment of pruritus from administration of neuraxiai opiates? A. Nalbuphine 5 mg TV B. Dexmedetomidine 30 meg IV C. Diphenhydramine 50 mg IV D. Hydroxyzine 20 mg TM E. Propofol 10 mg IV
(B) The treatment of pruritus from the administration of neuraxial opiates is primarily with opioid antagonists, mixed opioid agonist-antagonist, and antihistamine drugs. Nalbuphine is a mixed opioid agonist-antagonist; diphenhydramine and hydroxyzine have antihistamine properties. Propofol at very low doses has been useful to treat pruritus not only induced by neuraxial opiates but also the pruritus associatcd with cholestatic liver disease. Dexmedetomidine is a highly selective a,-receptor agonist that has a faster onset and shorter duration of action compared to clonidine. Dexmedetomidine has analgesic properties, can potentiate neuraxial analgesia when injected spinally, and can perhaps decrease the incidence of pruritus if the narcotic dose is reduced. It is not used to treat pruritus. When administered IV it would cause sedation, as will as lower the blood pressure and heart rate
Cutaneous innervation of the plantar surface of the foot is provided by the A. Sural nerve B. Posterior tibial nerve C. Saphenous nerve D. Deep peroneal nerve E. Superficial peroneal nerve
(B) There are five nerves that supply the ankle and foot: the posterior tibial, sural, superficial and deep peroneal, and saphenous nerves. These nerves are superficial at the level of the ankle and are easy to block. The posterior branch of the tibial nerve gives rise to the medial and lateral plantar nerves, which supply the plantar surface of the foot.
What is the storage life of whole blood stored with citrate phosphate dextrose (CPD)? A. 14 days B. 21 days C. 35 days D. 42 days E. 49 days
(B) There are many preservation solutions used for whole blood and RBCs. Acid citrate dextrose (ACD), CPD, and citrate phosphate double dextrose (CP2D) each allows blood to have a shelf life of 21 days. In 1978, the FDA approved the additive adenine to CPD. This extended the shelf life of blood by 2 weeks. CPDA-l has a shelf life of 35 days. These solutions were used mainly for whole blood. However, when component therapy became more widespread it was noted that packing the RBCs by removing the plasma removed a significant amount of adenine and glucose as well. By using an additive solution (which contains primarily adenine, glucose, and saline) to the CPD or CP2D whole blood that has the plasma removed, the "packed" RBCs can now be stored for 42 days. The three different additive solutions currently used in the United States are Adsol (AS-I), Nutricel (AS-3), and Optisol (AS-5).
Six hours after a patient received a transfusion with 2 units of fresh frozen plasma and 1 unit of platelets, she presents with hypoxia, fever, and noncardiogenic pulmonary edema. What complication do you suspect? (A) Post-transfusion purpura (B) Transfusion-related acute lung injury (C) Delayed hemolytic reaction (D) Transfusion-related immunomodulation.
(B) Transfusion-related acute lung injury Transfusion-related acute lung injury ( TRALI) presents as hypoxia, often acute; ever and noncardiogenic pulmonary edema within 6 hours of a blood product transfusion, especially fresh frozen plasma or platelets. A would occur from development of platelet allo-antibodies and noted in the precipitous platelet count drop 5-10 days after transfusion. Because TRALI is a type of nonhemolytic reaction, C is incorrect. D would manifest as diminished immuno-responsiveness and inflammation promotion.
Which of the following correctly describes the effect of transposition of the great arteries on the rate of induction of anesthesia? A. Inhalation induction is faster than normā; intravenous induction is slower than normal B. Inhalation induction is slower than normal; intravenous induction is faster than normal C. Both inhalation and intravenous induction are faster than normal D. Both inhalation and intravenous induction arc slower than normal E. Inhalation induction is normal; intravenous induction is faster than normal
(B) Transposition of the great arteries is a congenital cardiac defect that results from failure of the truncus arteriosus to rotate during organogenesis such that the aorta arises from the right ventricle and the pulmonary artery arises from the left ventricle. As a result, the left and right ventricles are not connected in series and the pulmonary and systemic circulations function independently. This results in profound arterial hypoxemia; survival is not possible unless there is a concomitant defect that allows for intermixing of blood between the two circulations. Induction of anesthesia with volatile anesthetics will be delayed because minimal portions of inhaled drugs will reach the systemic circulation. In contrast, anesthetic drugs that are administered intravenously will be distributed with minimal dilution to the brain; therefore, doses and rates of injection should be reduced in these patients.
What nerve injury is most likely to occur when the arm is pronated? (A) Brachial plexus (B) Ulnar nerve (C) Radial nerve (D) Suprascapular nerve
(B) Ulnar nerve To avoid injury to the ulnar nerve, the forearm is supinated. An additional measure to avoid injury include the use of elbow padding and flexing elbows <90 degrees.
Which o the following is not a risk factor for developing cauda equine syndrome? (A) Lidocaine spinal anesthesia (B) Use of glucose to increase baricity of neuraxial anesthetics (C) Epidural anesthesia (D) Continuous spinal anesthesia (CSA)
(B) Use of glucose to increase baricity of neuraxial anesthetics. Injuries have occurred with CSA most likely because of increased anesthetic doses administered to compensate for an inadequate block. Toxicity can occur with accidental intrathecal injection through what was intended to be an epidural injection. Most cases of cauda equine syndrome due to local anesthetic neurotoxicity have occurred with the use of lidocaine. Recent cases of cauda equine syndrome have been associated with markedly hyperbaric solutions. Despite this, there is no evidence to suggest that hyperbaric solutions are responsible.
A 70 kg adult man presents for emergent exploratory laparotomy after free air is seen on abdominal imaging. In addition, his serum sodium is 160 mEq/L. Which of the following is NOT true? (A)A relatively higher concentration of sevoflurane will be needed for adequate anesthesia. (B)The fastest rate at which his sodium should be corrected is 1.5 mEq/L/h. (C)His condition would likely be worsened by administration of demeclocycline. (D)Rapid correction of his sodium level could result in permanent neurologic deficit.
(B)The fastest rate at which his sodium should be corrected is 1.5 mEq/L/h. In general, plasma sodium concentration should not be decreased faster than 0.5 mEq/L/h. Rapid correction of hypernatremia can result in permanent neurologic damage, as well as seizures and brain edema. Hypernatremia increases the minimum alveolar concentration for inhaled anesthetics. Demeclocycline is a tetracycline antibiotic that interferes with the action of ADH. By blocking ADH at its receptor, demeclocycline impairs the ability of the kidneys to concentrate urine, and therefore may worsen hypernatremia. Because of this effect, demeclocycline is used as off label treatment for SIADH. Hypernatremia increases the MAC of volatile anesthetics.
After emergency repair of a ruptured abdominal aortic aneurysm, a 68-year-old patient is mechanically ventilated in the intensive care unit with 20 cm H20 of positive end-expiratory pressure (PEEP) for 3 days. Sodium nitroprusside has been infused at a rate of 1.5 J.1g1kglmin for 48 hours to control hypertension. Suddenly, the systemic blood pressure falls from 130/70 to 50 mm Hg systolic and the Sáo drops to 75%. The most likely cause of this scenario is: A. Cyanide toxicity B. Acute myocardial infarction C. Tension pneumothorax D. Hyperventilation E. Methemoglobinemia
(C) PEEP is produced by the application of positive pressure to the exhalation valve of the mechanical ventilator at the conclusion of the expiratory phase. PEEP is often used to increase arterial oxygenation when FI02 exceeds 0.50 to reduce the hazard of 02 toxicity. PEEP increases lung compliance and functional residual capacity by expanding previously collapsed but perfused alveoli, thus improving ventilation/perfusion matching and reducing the magnitude of the rightto-left transpulmonary shunt. There are, however, a number of potential hazards associated with the use of PEEP. These include decreased cardiac output, pulmonary barotrauma (i.e., tension pneumothorax), increased extravascular lung water, and redistribution of pulmonary blood flow. Barotrauma, such as pneumothorax, pneumomediastinum, and subcutaneous emphysema, occurs as a result of overdistention of alveoli by PEEP. Pulmonary barotrauma should be suspected when there is abrupt deterioration of arterial oxygenation and cardiovascular function during mechanical ventilation with PEEP. If barotrauma is suspected, a chest x-ray should be obtained and if a tension pneumothorax is present, a chest tube should be placed in the involved chest cavit
Normal resting myocardial Ó consumption is A. 2.0 mUIOO g/min B. 3.5 mUI00 g/min C. 10 mL/IOO g/min D. 15 mLlI 00 g/min E. 25 mLII 00 g/min
(C) Myocardial preservation is achieved during cardiopulmonary bypass primarily by infusing cold (4°C) cardioplegia solutions containing potassium chloride 20 mEqlL. This rapidly produces hypothermia of the cardiac muscle and a flaccid myocardium. In the normal contracting muscle at 37°C, myocardial Ó consumption is approximately 8 to 10 mL/lOO g/min. This is reduced in the fibrillating heart at 22°C to approximately 2 mUI00 g1min. Myocardial Ó consumption of the electromechanically quiescent heart at 22°C is less than 0.3 mUI00 g1min
Normal resting coronary artery blood flow is A. 10 mUIOO glmin B. 40 mUIOO glmin C. 80 mUIOO glmin D. 120 mLlIOO glmin E. 160 mLlI 00 glmin
(C) Resting coronary artery blood flow is approximately 80 mUI00 g/min, or approximately 3% to 5% of the cardiac output. Resting myocardial 02 consumption is 8 to 10 mUIOO g/min, or approximately 10% of the total body consumption of 02
Which of the following is the earliest sign of lidocaine toxicity? A. Shivering B. Nystagmus C. Lightheadedness and dizziness D. Tonic-clonic seizures E. Nausea and vomiting
(C) Toxic reactions to local anesthetics are usually due to intravascular or intrathecal injection or to an excessive dosage. The initial symptoms of local anesthetic toxicity are lightheadedness and dizziness. Patients also may note perioral numbness and tinnitus. Progressive central nervous system (CNS) excitatory effects include visual and auditory disturbances, shivering, twitching, and ultimately generalized tonic-clonic seizures. CNS depression can ensue, leading to respiratory depression or arrest.
Which of the following would be the most likely cause of oozing in a patient transfused with 10 units of packed red blood cells (RECs)? A. Citrate toxicity B. Low factor V C. Low fibrinogen D. Dilutional thrombocytopenia E. Low factor VIII
(C) With the massive transfusion or whole blood or RBCs (i.e., > I circulating blood volume = 10 units for a 70-kg adult within 24 hours), you can expect to see a decrease in clolling factors and platelets. BOlh whole blood and packed RBCs are stored at about 4°C. At this temperature platelet activity rapidly decreases, and by 24 to 48 hours platelet activity is only 5% to 10%. The labile factors V and VIII also rapidly decrease at this temperature, whereas the other clotting factors are relatively stable. With massive transfu sion of whole blood, dilutional thrombocytopenia develops early. Because packed RBCs contain little plasma, bleeding tendencies are different after massive transfusion compared to whole blood transfusions. In the case of massive isovolemic RBC transfusion (crystalloid + RBCs) you first see a decrease in fibrinogen fo llowed by a decrease in factors V and VIII and then thrombocytopenia. Transfusion practices should be guided by the patient's clinical status and laboratory tests. With rapid transfusion, the citrate in blood may lead to a transient fall in ionized calcium levels. This is not associated with oozing (
What does the National Institute or Occupational Safety and Health (NIOSH) recommend for the room concentration of a halogenated agent when nitrous oxide is used? (A) 25 ppm (B) 2 ppm (C) 0.5 ppm (D) 2.5 ppm
(C) 0.5 ppm The National institute for Occupational Safety and Health (NIOSH) recommend limiting the room concentration o nitrous oxide to 25 ppm and halogenated agent to 2 ppm and 0.5 ppm when nitrous oxide is also used.
Which of the following is appropriate to use for intravenous regional anesthesia? (A) 0.5% lidocaine with epinephrine 50 mL (B) 5.0% lidocaine with epinephrine 40 mL (C) 0.5% lidocaine 50 mL (D) 0.5% bupivacaine 50 mL
(C) 0.5% lidocaine 50 mL Vasoconstrictors are contraindicated in regional blocks involving extremities. Low versus high local anesthetic concentration is used. In addition, preservatives are contraindicated. Bupivacaine should not be used in light o potential systemic toxicity.
A patient with mitral stenosis is asymptomatic with occasional mild symptoms with exertion. Which mitral valve area is associated with these symptoms? (A) 0.2-0.5 cm 2 (B) 0.5-1.0 cm 2 (C) 1.5-2.0 cm 2 (D) 2.0-2.5 cm 2
(C) 1.5-2.0 cm 2 Patients with valve areas between 1.5 and 2.0 cm2 are usually asymptomatic or have only mild symptoms with exertion. Critical mitral stenosis is associated with valve are 0.5-1.0 cm2 or less. Mitral stenosis is usually diagnosed when the valve area is 1.5 cm2 or less.
After placing a spinal anesthetic the sensory block is assessed at 8. Where is the most likely level of the motor block? (A) 4 (B) 6 (C) 10 (D) 2
(C) 10 A motor block typically is typically two or more segments below the sensory block
What is the smallest volume o in used ABO- incompatible donor blood that will cause an acute hemolytic reaction? (A) 40-60 mL (B) 25-30 mL (C) 10-15 mL (D) 1-3 mL
(C) 10-15 mL Acute hemolytic reactions may occur a ter in usion with as little as 10-15 mL o ABOincompatible blood and may result in death or 20-60% o patients.
During laparoscopic bariatric surgery, you apply positive end expiratory pressure (PEEP). What is the recommended upper limit? (A) 5 cm H2O (B) 10 cm H2O (C) 15 cm H2O (D) 20 cm H2O
(C) 15 cm H2O When using large tidal volumes, oxygenation may be impaired. Limit PEEP to 15 cm H2O.
What is size of the transfer tubing in the scavenger system? (A) 22 mm (B) 20 mm (C) 19 mm (D) 9 mm
(C) 19 mm Rationale: Transfer tubing is 19 or 30 mm.
What is the outer diameter of the scavenger tubing? (A) 22- mm (B) 32- mm (C) 19- mm (D) 10- mm
(C) 19- mm The outer diameter of the scavenger tubing is 19- mm; the outer diameter or the common gas outlet is 22- mm.
Which is a normal functional residual capacity? (A) 500 mL (B) 1,200 mL (C) 2,300 mL (D) 1,100 mL
(C) 2,300 mL Which is a normal functional residual capacity? (A) 500 mL (B) 1,200 mL (C) 2,300 mL (D) 1,100 mL Rationale: A) is tidal volume, B) residual volume, and D) is expiratory reserve volume. Functional residual capacity is a combination o maximal volume that can be expired below tidal volume and the volume remaining a ter maximal exhalation.
A 62-year-old patient is scheduled to undergo resection of a frontal lobe intracranial tumor under general anesthesia. Preoperatively, the patient is alert and oriented, and has no focal neurologic deficits. Within what range should Pacó be maintained? A. 15 and 20 mm Hg B. 20 and 25 mm Hg C. 25 and 30 mm Hg D. 30 and 35 mm Hg E. 35 and 40 mm Hg
(C) 25 and 30 mm Hg Cerebral ischemia has been reported in both humans and laboratory animals when the Pacó is reduced below 20 mm Hg. It is likely that cerebral ischemia is caused by a leftward shift of the oxyhemoglobin dissociation curve (produced by the severe alkalosis) and possibly by intense cerebral vasoconstriction. A leftward shift of the oxyhemoglobin dissociation curve increases the affinity of hemoglobin for Ó, which reduces off-loading of Ó from hemoglobin at the capillary bed. This effect combined with decreased CBF can result in cerebral ischemia. Combined with the fact that there is very little additional benefit in terms of reducing CBV and ICP, it is recommended to limit acute hyperventilation of the lungs to a Pac02 of 25 to 30 mm Hg. Within this range, reduction in ICP is maximal and risk of cerebral ischemia is minimal.
What are the fluid requirements for redistribution and evaporative surgical fluid losses during a bowel resection? (A) 0-2 mL/kg (B) 2-4 mL/kg (C) 4-8 mL/kg (D) 10-14 mL/kg
(C) 4-8 mL/kg Redistribution and evaporative loss are replaced according to the degree of tissue trauma sustained during surgery: minimal tissue trauma (e.g., herniorrhaphy/short super cial procedure) requires 0-2 mL/kg; moderate tissue trauma (e.g., cholecystectomy) requires 2-4 mL/kg; and severe tissue trauma (e.g., bowel resection) requires 4-8 mL/kg.
What is the granule size commonly used in CÓ absorbent? (A) 2-4 mesh (B) 6-8 mesh (C) 4-8 mesh (D) 1-2 mesh
(C) 4-8 mesh Granule size is a compromise between the higher absorptive surface area of small granules and the lower resistance to gas flow of larger granules. The granule size commonly used in CÓ absorbent is between 4 and 8 mesh.
When the pressure gauge drops below 745 psig on a nitrous oxide E-cylinder at room temperature, approximately how much nitrous oxide is left in the tank? (A) 1,590 L (B) 660 L (C) 400 L (D) 625 L
(C) 400 L E-cylinder nitrous oxide tanks contain nitrous oxide in the liquid and gas state. T e only accurate way to determine the amount o gas le t in the tank is by weighing it. A ull E-cylinder tank will hold 1,590 liters o nitrous oxide. When the liquid orm is consumed and the tank pressure drops below 745 psig, the amount o nitrous oxide in the gas phase is about 400 liters.
What is the average distance from the skin to the epidural space? (A) 1 cm (B) 1.5 cm (C) 5 cm (D) 7.5 cm
(C) 5 cm The distance from the skin to the epidural space ranges from 2.5-8 cm.
Preoxygenation results in how many minutes of oxygen reserve? (A) 1-3 minutes (B) 3-6 minutes (C) 5-8 minutes (D) >8 minutes
(C) 5-8 minutes Preoxygenation affords approximately 5-8 minutes of oxygen reserve.
What dose of protamine sulfate would be appropriate to reverse 5,000 units of heparin? (A) 500 µg (B) 5 mg (C) 50 mg (D) 5 µg
(C) 50 mg Protamine is a positively charged protein that binds to and inactivates heparin. Protamine is therefore dosed according the dose of heparin given and not the degree of anticoagulation obtained. Generally 1 mg of protamine is administered for every 100 units of heparin in circulation. Therefore, this patient needs 5,000/100 = 50 mg of protamine IV.
You are planning to add fentanyl to the epidural for labor. How much will you add to the local anesthetic solution? (A) 5 mg (B) 10 µg (C) 50 µg (D) 0.5 mg
(C) 50 µg Fentanyl 50-150 µg is the appropriate dose as an addition to labor epidural analgesia.Morphine 5 mg is also useful as well as meperidine (50-100 µg) or Sufentanil (5-20 µg).
The normal vital capacity for a 70-kg man is A. 1 L B. 2L C. 5L D. 7L E. 9L
(C) 5L The volume of gas exhaled during a maximum expiration is the vital capacity. In a normal healthy adult, the vital capacity is 60 to 70 mLlkg. In a 70-kg patient, the vital capacity is approximately 5 L
During a repeat cesarean section a term infant is delivered. On assessment at 1 minute, the infant has a heart rate of 90, blue extremities, whimpering to stimulus, breathing regularly, and active with good muscle tone. What is the 1 minute Apgar score? (A) 5 (B) 6 (C) 7 (D) 8
(C) 7 Apgar scores are calculated for this patient as such: 2 points to regular breathing and active/good muscle tone. 1 point is given each for a HR <100 bpm, acrocyanosis and whimpering. Scores 0-4 are regarded as severely depressed, 4-7 as mildly depressed, and 8-10 as vigorous.
Which class of nerve fiber will be the site of therapeutic stimulation for a transcutaneous electrical nerve stimulation ( TENS) unit? (A) A δ ibers (B) C fibers (C) A ß fibers (D) B fibers
(C) A ß fibers TENS units are effective through activation of large diameter afferent fibers such as Aß fibers. Aδ, B, and C fibers all have comparably smaller diameters
A 40-year-old male with a history of well-controlled hypertension is scheduled for a carpal tunnel release. How will you classify the patient? (A) ASA IV (B) ASA III (C) ASA II (D) ASA I
(C) ASA II The American Society o Anesthesiologists (ASA) Physical Status Classification is used to assign patients a physical status prior to anesthesia and surgery. The patient's history of well- controlled hypertension is considered a mild systemic disease.
Afterload reduction is beneficial during anesthesia for noncardiac surgery in patients with each of the following conditions EXCEPT A. Aortic insufficiency B. Mitral regurgitation C. Tetralogy of Fallot D. Congestive heart failure E. Patent ductus arteriosus
(C) Afterload reduction during anesthesia is beneficial in all of the conditions listed in this question except tetralogy of Fallot. In tetralogy of Fallot, blood is shunted through a ventricular septal defect from the pulmonary circulation to the systemic circulation because of right ventricular outflow obstruction. A decrease in systemic vascular resistance would augment this right-to-Ieft shunt through the ventricular septal defect, which will reduce pulmonary vascular blood flow and exacerbate systemic hypoxemia.
AFluotec (halothane) vaporizer will deliver an accurate concentration of an unknown volatile anesthetic if the latter shared which property with halothane? A. Molecular weight B. Viscosity C. Vapor pressure D. Blood/gas partition coefficient E. Oil/gas partition coefficient
(C) Agent-specific vaporizers, such as the Fluotec (halothane) vaporizer, are designed for each volatile anesthetic. However, volatile anesthetics with identical saturated vapor pressures could be used interchangeably with accurate delivery of the volatile anesthetic.
Which term describes full drug activation of a receptor? (A) Antagonist (B) Partial agonist (C) Agonist (D) Noncompetitive antagonist
(C) Agonist Drugs that are agonists fully activate a receptor. Partial agonists activate parts of a receptor. Antagonists bind, but do not activate receptors. Noncompetitive antagonists irreversibly bind to a receptor.
The P 50 of sickle cell hemoglobin is A. 19mmHg B. 26mmHg C. 31 mmHg D. 35 mmHg E. 40mmHg
(C) Also see explanation to question 109. A P50 less than 26 mm Hg defines a leftward shift of the oxyhemoglobin dissociation curve. This means that at any given Páo, hemoglobin has a higher affinity for 02' A P 50 greater than 26 mm Hg describes a rightward shift of the oxyhemoglobin dissociation curve. This means that at any given Páo, hemoglobin has a lower affinity for 02' Conditions that cause a rightward shift of the oxyhemoglobin dissociation curve are metabolic and respiratory acidosis, hyperthermia, increased erythrocyte 2,3-DPG content, pregnancy, and abnormal hemoglobins, such as sickle cell hemoglobin or thalassemia. Alkalosis, hypothermia, fetal hemoglobin, abnormal hemoglobin species, such as carboxyhemoglobin, methemoglobin, and sulfhemoglobin, and decreased erythrocyte 2,3-DPG content will cause a leftward shift of the oxyhemoglobin dissociation curve.
A 78-year-old patient is anesthetized for resection of a liver tumor. After induction and tracheal intubation, a 20-gauge arterial line is placed and connected to a transducer that is located 20 cm below the level of the heart. The system is zeroed at the stopcock located at the wrist while the patient's arm is stretched out on an arm board. How will the arterial line pressure compare with the true blood pressure? A. It will be 20 mm Hg higher B. It will be 15 mm Hg higher C. It will be the same D. It will be 15 mm Hg lower E. It will be 20 mm Hg lower
(C) Also see explanation to question 3. It is important to zero the electromechanical transducer system with the reference point at the approximate level of the heart. This will eliminate the effect of the fluid column of the transducer system on the arterial blood pressure reading of the system. In this question, the system was zeroed at the stopcock, which was located at the patient's wrist (approximate level of the ventricle). Blood pressure expressed by the arterial line will, therefore, be accurate, provided the distance between the patient's wrist and the stopcock remains 20 cm.
What is the correct order of structures (from cephalad to caudad) in the intercostal space? A. Nerve, artery, vein B. Vein, nerve, artery C. Vein, artery, nerve D. Artery, nerve, vein E. Artery, vein, nerve
(C) An intercostal nerve block is performed with the patient in the prone position. The needle is inserted about 8 cm lateral to the midline posteriorly. If the needle is inserted more laterally, the lateral cutaneous branches of the intercostal nerves may be missed as they arise at the midaxillary line. The needle is advanced until the rib is contacted and is then "walked off' the inferior border of the rib. Five milliliters of local anesthetic is injected after the needle has been advanced 2 to 3 mm. The most common complications of this block are intravascular injection and pneumothorax
A 46-year-old paticnt with Crohn's disease is schedulcd for a colcctomy under general ancsthesia. The patient has a history of rhcumatic fever with modcratc mitral regurgiLation. Which of the fOllowing antibiotics would be thc most appropriate choice ror prophylaxis against subacute bactcrial cndocarditis in this patient? A. Ampicillin and erythromycin B. Erythromycin and gcntamycin C. Ampicillin and gentamycin D. Clindamycin E. Penicillin
(C) Antimicrobial prophylaxis is useful in preventing bacterial endocarditis in patients with valvular heart disease, prosthetic heart valves, and other cardiac abnormalities, such as mitral prolapse, when these patients undergo procedures associated with transient bacteremia. Antimicrobial agents used for prophylaxis should be directed toward streptococci, enterococci, and staphylococci. Tracheal intubation is not an indication for prophylaxis per se. Currently, the recommended antibiotic regimen for patients needing prophylaxis for bacterial endocarditis includes ampicillin, I to 2 g IV 30 minutes before surgery, and gentamicin, 1.5 mg/kg IV 30 minutes before surgery. These doses should be repeated 8 hours after the initial dose. For patients with penicillin allergy, prophylaxis should be achieved with vancomycin, I g IV slowly, starting one hour before surgery
Which is not an indication for cryoprecipitate administration? (A) Fibrinogen levels <80-100 mg/dL (B) Factor XIII deficiency (C) Antithrombin deficiency (D) Preoperative prophylaxis for patient with von Willebrand disease
(C) Antithrombin deficiency Cryoprecipitate contains factor VIII, von Willebrand factor (vWF), fibrinogen, fibronectin, and factor XIII. Although actor-specifc concentrates can be administered for patients with hemophilia and von Willebrand disease, it remains an indication for cryoprecipitate administration. Cryoprecipitate is typically administered for documented for suspected fibrinogen levels < 80-100 mg/dL. Antithrombin deficiency is an indication for fresh frozen plasma administration.
Which valve disorder most likely predisposes a patient to coronary ischemia with hypotension? (A) Mitral stenosis (B) Mitral regurgitation (C) Aortic stenosis (D) Aortic regurgitation
(C) Aortic stenosis Patients with advanced aortic stenosis are extremely sensitive to hypotension. Aortic stenosis leads to left ventricular hypertrophy due to elevated left ventricular pressures. This leads to both an increase in oxygen demand (hypertrophy and increased left ventricular systolic pressures) and a decrease in myocardial perfusion due to left ventricular end-diastolic pressure, which is elevated even early in disease progression
Which anticholinergic increases heart rate the most? ( A) Scopolamine (B) Glycopyrrolate (C) Atropine (D) Pyridostigmine
(C) Atropine While all anticholinergics increase heart rate, scopolamine exerts the least e ect ollowed by glycopyrrolate. Pyridostigmine is a cholinesterase inhibitor.
Which anticholinergic increases heart rate the most? (A) Scopolamine (B) Glycopyrrolate (C) Atropine (D) Pyridostigmin
(C) Atropine While all anticholinergics increase heart rate, scopolamine exerts the least effect followed by glycopyrrolate. Pyridostigmine is a cholinesterase inhibitor.
Calculate cerebral perfusion pressure based on the following data: ICP 25 mm Hg, central venous pressure 15 mm Hg, systolic blood pressure 120 mm Hg, diastolic pressure 90 mm Hg, pulmonary artery occlusion pressure 10 mm Hg A. 95 mmHg B. 85 mmHg C. 75 mmHg D. 65 mmHg E. 55 mmHg
(C) Autoregulation of cerebral vasomotor tone maintains CBF within a narrow range over a wide range of mean systemic arterial blood pressures or cerebral perfusion pressures. The relationship between cerebral blood flow, cerebral perfusion pressure (CPP), and cerebrovascular resistance (CVR) is expressed as follows. Cerebral perfusion pressure can be approximated as the difference in mean arterial pressure (MAP) and ICP.Cerebral perfusion pressure approximates mean arterial pressure when the cranium is open. Mean systemic arterial blood pressure can be approximated as 113 the systolic blood pressure plus 2/3 the diastolic pressure or diastolic plus 113 the pulse pressure (i.e., systolic-diastolic blood pressure). In this patient, the cerebral perfusion pressure is 75 mm Hg.
Because you are concerned with monitoring factors contributing to cerebral ischemia during mediastinoscopy, where will you place your monitors? (A) Blood pressure cuff on right arm; arterial line in left hand (B) Blood pressure cuff on right arm; pulse oximeter on right hand (C) Blood pressure cuff on left arm; arterial line in right hand (D) Blood pressure cuff on left arm; pulse oximeter on left hand
(C) Blood pressure cuff on left arm; arterial line in right hand Because the mediastinoscope can compress the innominate artery as it passed through the upper thorax, there is concern about a decrease in blood flow to the right common carotid artery, to the right vertebral artery and a decrease in subclavian flow to the right hand; therefore, monitoring perfusion to the right hand with either a pulse oximeter waveform or radial arterial waveform can detect decreased flow to the right arm.
What statement is true regarding a patient who is awake in the supine position? (A) The blood pressure decreases due to autoregulation. (B) Venous return decreases. (C) Blood pressure remains relatively constant. (D) Sympathetic out low increases.
(C) Blood pressure remains relatively constant. When a patient goes from standing to the supine position, venous return increases. Sympathetic out ow decreases while parasympathetic activity increases due to activation of afferent baroreceptors. Activated atrial and ventricular receptors also decrease sympathetic outflow. These processes along with activation of atrial reflexes results in maintenance of arterial blood pressure.
The expression that for a fixed mass of gas at constant temperature, the product of pressure and volume is constant is known as A. Graham's law B. Bernoulli's law C. Boyle's law D. Dalton's law E. Charles' law
(C) Boyle's law states that for a fi xed mass of gas at constant temperature, the product of pressure and volume is constant. This concept can be used to estimate the volume of gas remaining in a compressed-gas cylinder by measuring the pressure within the cylinder.
Which muscle is likely to be unaffected by an axillary brachial plexus block? (A) Abductor pollicis brevis (B) Interosseous (C) Brachialis (D) Pronator teres
(C) Brachialis The axillary block is one of the most common nerve blocks and potential for serious complication is low; however, the block is often incomplete. Blockade is at the level of terminal nerves after separation of the musculocutaneous nerve, which requires an additional injection for a complete block. The musculocutaneous nerve enters the coracobrachialis muscle, which it innervates, and goes on to supply the biceps brachii and the brachialis. Sensory innervation is provided to the skin on the radial side of the forearm to the radiocarpal joint.
Which factors will exacerbate mitral regurgitation? (A) tachycardia and acute increases in afterload. (B) tachycardia and acute decreases in afterload. (C) Bradycardia and acute increases in afterload. (D) Bradycardia and acute decreases in afterload.
(C) Bradycardia and acute increases in afterload. Although the anesthetic management will be tailored according to the severity o the mitral regurgitation, in general, factors such as slow heart rate and acute increases in afterload should be avoided in order to prevent exacerbation o disease. A normal to slightly fast heart rate as well as afterload reduction will improve forward flow.
Which of the flowing local anesthetics and dosages are used for cesarean section with spinal anesthesia? (A) Lidocaine (100 mg) (B) tetracaine (14 mg) (C) Bupivacaine (12 mg) (D) Mepivacaine (16 mg)
(C) Bupivacaine (12 mg) The dose of spinal lidocaine for cesarean section is 50 to 60 mg; bupivacaine (10 to 15 mg); and tetracaine (7 to 10 mg). Mepivacaine is not administered or spinal anesthesia or cesarean section
Which o the ollowing local anesthetics and dosages are used or cesarean section with spinal anesthesia? (A) Lidocaine (100 mg) (B) Tetracaine (14 mg) (C) Bupivacaine (12 mg) (D) Mepivacaine (16 mg)
(C) Bupivacaine (12 mg) The dose of spinal lidocaine or cesarean section is 50 to 60 mg; bupivacaine (10 to 15 mg); and tetracaine (7 to 10 mg). Mepivacaine is not administered for spinal anesthesia or cesarean section.
A 32-year-old male is found unconscious by the fire department in a room where he has inhaled 0.1 % carbon monoxide for a prolonged period. His respiratory rate is 42 breaths/min, but he is not cyanotic. Carbon monoxide has increased this patient's minute ventilation by which of the following mechanisms. A. Shifting the 02 hemoglobin dissociation curve to the left B. Increasing CÓ production C. Causing lactic acidosis D. Decreasing Páo E. Producing methemoglobin
(C) Carbon monoxide inhalation is the most common immediate cause of death from fire. Carbon monoxide binds to hemoglobin with an affinity 240 times greater than that of oxygen. For this reason very small concentrations of carbon monoxide can greatly reduce the oxygen-carrying capacity of blood. In spite of this, the arterial Páo often is normal. Because the carotid bodies respond to arterial Páo, there would not be an increase in minute ventilation until tissue hypoxia were sufficient to produce lactic acidosis .
How is cardiac index calculated? (A) Cardiac Output/ Stroke Volume (B) Cardiac Output / Systemic Vascular Resistance (C) Cardiac Output / Body Surface Area (D) Cardiac Output / Heart Rate
(C) Cardiac Output/ Body Surface Area Cardiac index is a measure of cardiac output comparable among individuals of different body habitus. It is calculated by dividing the cardiac output by the body surface area.
An 80-year-old female with moderate aortic stenosis is undergoing an emergent open reduction and internal fixation of her left hip. Preoperative vital signs include a blood pressure of 175/95 mmHg and a heart rate in sinus rhythm of 65 beats per minute. Shortly after induction with propofol and general anesthesia maintained with sevo urane, the patient's heart rate increases to an irregular 133 beats per minute. The blood pressure decreases to 69/55 mmHg. What would be the most e ective action to restore the patient to a stable hemodynamic profile? (A) Administer 100 µg of phenylephrine intravenously. (B) Request that the surgery begin immediately so that a painful stimulus may increase blood pressure. (C) Cardiovert the patient with a synchronized transthoracic shock of 170 joules. (D) Administer a 500 mL bolus of Lactated Ringer's
(C) Cardiovert the patient with a synchronized transthoracic shock of 170 joules. The irregular accelerated heart rate is likely atrial fibrillation. Loss of atrial synchronized contraction can reduce ventricular filling by 20-30%. An elderly patient with atrial stenosis has a fixed out ow obstruction and can be expected to have hypertrophy, resulting in decreased ventricular compliance. T e increased heart rate and decreased atrial "kick" all combine to significantly decrease this patient's left ventricular end-diastolic volume. Hemodynamic consequences to a reduced ventricular end-diastolic volume will be most pro oundly seen in a patient with concomitant reduced ventricular compliance. While all o the interventions mentioned may increase blood pressure, only synchronized cardioversion solves the underlying problem
A 62-year-old patient is scheduled to undergo resection of a frontal lobe intracranial tumor under general anesthesia. Preoperatively, the patient is alert and oriented, and has no focal neurologic deficits. Within what range should Pacó be maintained? A. 15 and 20 mm Hg B. 20 and 25 mm Hg C. 25 and 30 mm Hg D. 30 and 35 mm Hg E. 35 and 40 mm Hg
(C) Cerebral ischemia has been reported in both humans and laboratory animals when the Pacó is reduced below 20 mm Hg. It is likely that cerebral ischemia is caused by a leftward shift of the oxyhemoglobin dissociation curve (produced by the severe alkalosis) and possibly by intense cerebral vasoconstriction. A leftward shift of the oxyhemoglobin dissociation curve increases the affinity of hemoglobin for Ó, which reduces off-loading of Ó from hemoglobin at the capillary bed. This effect combined with decreased CBF can result in cerebral ischemia. Combined with the fact that there is very little additional benefit in terms of reducing CBV and ICP, it is recommended to limit acute hyperventilation of the lungs to a Pac02 of 25 to 30 mm Hg. Within this range, reduction in ICP is maximal and risk of cerebral ischemia is minimal.
An unconscious 19-year-old woman with closed head injUly is in the intensive care unit after a motor vehicle accident. The following hemodynamic values are noted: blood pressure 110/80 mm Hg, heart rate 96 beats/min, right atrial pressure 10 111m Hg, ICP 40 mm Hg. What is the cerebral perfusion pressure? A. 80 mm Hg B. 70 mm Hg C. 50 mm Hg D. 40 mm Hg E. 35 mm Hg
(C) Cerebral perfusion pressure is defined as the difference in mean systemic arterial blood pressure and ICP. Thus, cerebral perfusion pressure in this patient is 50 mm Hg.
An unconscious 19-year-old woman with closed head injury is in the intensive care unit after a motor vehicle accident. The following hemodynamic values are noted: blood pressure 110/80 mm Hg, heart rate 96 beats/min, right atrial pressure 10 111m Hg, ICP 40 mm Hg. What is the cerebral perfusion pressure? A. 80 111m Hg B. 70 mm Hg C. 50 mm Hg D. 40 mm Hg E. 35 mm Hg
(C) Cerebral perfusion pressure is defined as the difference in mean systemic arterial blood pressure and ICP. Thus, cerebral perfusion pressure in this patient is 50 mm Hg.
The most rapid maneuver available for lowering ICP in a patient with a large intracranial mass is A. Mannitol, 1 glkg IV B. Ketamine, 1 mglkg IV C. Hyperventilation to 25 mm Hg Pacó D. Furosemide, 1 mglkg IV E. Methylprednisolone, 30 mglkg
(C) Changes in plasma Pacó will affect cerebral vascular tone. Hypocarbia (associated with hyperventilation) will rapidly cause vasoconstriction, thereby reducing CBF, CBV, and ICP. Thus, hyperventilation is the technique that will be most rapidly available to decrease ICP in patients with an intracranial mass.
What would be the correct classification of hyperalgesia with sympathetic dysfunction following a traumatic injury that included direct nerve damage persisting beyond the standard healing period in the absence of other conditions that may be responsible for the pain? (A) Complex regional pain syndrome type I (B) Reflex sympathetic dystrophy (C) Complex regional pain syndrome type II (D) Persistent allodynia
(C) Complex regional pain syndrome type II Precipitating injury to the nerve itself identi es complex regional pain syndrome type II. type I does not include distinct injury to the nerve. Re ex sympathetic dystrophy is a synonym or type I
What is an indication of significant venous air embolism during a seated craniotomy? (A) Increased end-tidal carbon dioxide (B) Unchanged end-tidal carbon dioxide (C) Decreased end-tidal carbon dioxide
(C) Decreased end-tidal carbon dioxide Entraining large amounts of air into the venous system results in decreased end-tidal carbon dioxide.
During induction of general anesthesia, the pregnant patient quickly desaturates. Which factors most likely caused the desaturation? (A) Increased functional residual capacity and increased oxygen consumption (B) Decreased residual volume and increased expiratory reserve volume (C) Decreased functional residual capacity and increased oxygen consumption (D) Increased residual volume and decreased expiratory reserve volume
(C) Decreased functional residual capacity and increased oxygen consumption Respiratory changes of pregnancy include decreased functional residual capacity (FRC), increased oxygen consumption, and decreased residual and expiratory reserve volumes. Decreased FRC and increased oxygen consumptions lead to rapid decrease in oxygen saturation.
During induction of general anesthesia, the pregnant patient quickly desaturates. Which factors most likely caused the desaturation? (A) Increased functional residual capacity and increased oxygen consumption (B) Decreased residual volume and increased expiratory reserve volume (C) Decreased functional residual capacity and increased oxygen consumption (D) Increased residual volume and decreased expiratory reserve volume
(C) Decreased functional residual capacity and increased oxygen consumption. Respiratory changes of pregnancy include decreased functional residual capacity (FRC), increased oxygen consumption, and decreased residual and expiratory reserve volumes. Decreased FRC and increased oxygen consumptions lead to rapid decrease in oxygen saturation.
Which steroid has the smallest particulate size? (A) Methylprednisolone acetate (B) Triamcinolone diacetate (C) Dexamethasone sodium phosphate (D) Betamethasone
(C) Dexamethasone sodium phosphate Dexamethasone has the smallest particulate size, which minimizes the risk of vasoocclusive complications if inadvertently injected into a vessel during an epidural steroid injection.
The afferent input for somatosensory evoked potentials (SSEPs) is carried through which spinal cord tract? A. Spinocerebellar B. Spinothalamic C. Dorsal columns D. Corticospinal E. Vestibulospinal
(C) Dorsal Columns SSEPs are voltage signals that appear in response to electrical stimulation of peripheral nerves. The impulse elicited by electrical stimulation of a peripheral nerve ascends the ipsilateral dorsal column of the spinal cord, decussates in the medulla oblongata, and is ultimately recorded on the contralateral somatosensory cortex of the brain. SSEPs are composed of negative and positive voltage deflections with specific latencies and amplitudes. In general, the earlier deflections represent impulses and synapses within the spinal cord or brainstem, whereas the later impulses represent thalamic and/or cortical synapses. Intraoperative monitoring of SSEPs provides the ability to assess the integrity of the peripheral nerve (e.g., posterior tibial nerve, dorsal columns, brainstem, medial lemniscus, internal capsule, and contralateral somatosensory cortex)
Concerning the patient in question I, administration of 70% helium in Ó instead of 100% Ó will decrease the resistance to airflow through the stenotic region within the trachea because: A. Helium decreases the viscosity of the gas mixture B. Helium decreases the friction coefficient of the gas mixture C. Helium decreases the density of the gas mixture D. Helium decreases the Reynolds number of the gas mixture E. None of the above
(C) During orifice flow, the resistance to gas flow is directly proportional to the density of the gas mixture. Substituting helium for nitrogen will decrease the density of the gas mixture, thereby decreasing the resistance to gas flow (as much as threefold) through the region of constriction.
Which congenital cardiac malformation is most commonly associated with Down syndrome? (A) Transposition of the great vessels (B) Coarctation of the aorta (C) Endocardial cushion defect (D) Aortic stenosis
(C) Endocardial cushion defect Endocardial cushion de ects are the most common congenital cardiac malformations associated with Down syndrome.
Which volumes are included in vital capacity? (A)Tidal volume and residual volume (B) Residual volume and expiratory reserve volume (C) Expiratory reserve volume and inspiratory capacity volume (D) Inspiratory capacity volume and residual volume
(C) Expiratory reserve volume and inspiratory capacity volume. Expiratory reserve volume and inspiratory capacity volume comprise vital capacity.
Which of the following clotting factors is not synthesized by the liver? A. Factor II B. Factor VII C. Factor VIII D. Factor IX E. Factor X
(C) Factors IV (ionized calcium) and VIII are not synthesized by the liver. Factor 8 is synthesized by vascular endothelial cells and megakaryocytes and is involved in promoting coagulation via the intrinsic clotting.
Normal fetal heart rate (FHR) is A. 60 to 100 beats/min B. 100 to 140 beats/min C. 120 to 160 beats/min D. 150 to 200 beats/min E. None of the above
(C) Fetal monitors consist of a two-channel recorder for simultaneous recording of fetal heart rate and uterine activity. In looking at the FHR one assesses the baseline rate, the FHR variability, and the periodic changes (accelerations or decelerations) that occur with uterine contractions. The normal FHR varies between 120 and 160 beats/min. Some extend the lower limit of normal to 110 beats/min. Baseline FHRs less than 120 beats/min (bradycardia) and greater than 160 beats/min (tachycardia) have been associated with fetal asphyxia. Causes of fetal bradycardia include hypoxia, acidosis, congenital heart block, and some drugs. Causes of fetal tachycardia include infection, fever, maternal smoking, fetal paroxysmal supraventricular tachycardia, and some drugs (ritodrine, terbutaline, atropine). Normal heart rate beat-to-beat variability ranges ·between 5 and 20 beats/min. Lack of FHR beat -to-beat variability may be caused by drugs, such as benzodiazepines, opiates, volatile anesthetics, anticholinergics, fetal asphyxia, anemia, and prematurity
By what percentage is tissue metabolic rate reduced during cardiopulmonary bypass at 30°C? A. 35 B. 45 C. 55 D. 65 E. 75
(C) For each degree Celsius body temperature is lowered, tissue metabolic rate declines approximately 8%. At core temperature of 30°C would correspond roughly to a 56% reduction in metabolic rate
Which would result from excessive pressure on the sciatic nerve by the piriformis muscle? (A) Chronic pain in the perineum with voiding difficulty (B) Anterior thigh pain and weakness upon standing (C) Gluteal pain with paresthesia in the posterior thigh (D) Lumbar vertebral pain exacerbated by flexion of the lower back.
(C) Gluteal pain with paresthesia in the posterior thigh The sciatic nerve emerges from the greater sciatic foramen immediately approximate to the piriformis muscle. Nerve compression by this muscle results in gluteal pain and posterior paresthesia
What is the most common cause of acute epiglottitis? (A) Streptococcus pneumoniae (B) Allergic reaction (C) Haemophilus influenzae B (D) Viral in ection
(C) Haemophilus influenzae B Haemophilus influenzae B bacteria are the causative agent
For which infectious diseases is donor blood tested after it is collected, typed, and screened? (A) Hepatitis A, Hepatitis B, and Hepatitis C (B) Hepatitis B, Hepatitis C, and Hepatitis D (C) Hepatitis C, Syphilis, and Human Immunodeficiency Virus (D) Hepatitis C, Cytomegalovirus (CMV), and Syphilis
(C) Hepatitis C, Syphilis, and Human Immunodeficiency Virus Once donor blood is collected, it is typed, screened or antibodies, and tested or hepatitis B, hepatitis C, syphilis, and human immunodeciency virus (HIV).
Which of the following local anesthetics has the lowest ratio of dosage required for cardiovascular collapse to dosage required for central nervous system toxicity? A. Lidocaine B. Etidocaine C. Bupivacaine D. Prilocaine E. Chloroprocaine
(C) In general, in both in vivo and in vitro studies there is an overall direct correlation between anesthetic's potency and its direct depressant effect on myocardial contractility. The ratio of dosage required for cardiovascular collapse in animal models compared with that required to produce neurologic symptoms is the lowest for bupivacaine and levo-bupivacaine (2.0). Ratios for other local anesthetics are as follows: ropivacaine, 2.2; prilocaine, 3.1; procaine and chloroprocaine, 3.7; etidocaine, 4.4; lidocaine and mepivacaine.
Which hemodynamic event will decrease coronary per usion pressure the most? (A) Decreased systolic blood pressure (B) Decrease in left ventricular end-diastolic pressure (LVEDP) (C) Increase in pulmonary capillary wedge pressure (PCWP) (D) Increase in diastolic blood pressure
(C) Increase in pulmonary capillary wedge pressure (PCWP) Coronary perfusion pressure = arterial diastolic pressure minus the LVEDP. Any decreases in aortic pressure or increases in ventricular end-diastolic pressure will reduce coronary perfusion pressure. Since PCWP is an indirect measure of LVEDP, an increase in PCWP will decrease coronary perfusion pressure.
What is the best approach to avoiding cardiac arrest during spinal anesthesia? (A) Decrease preload (B) Give prophylactic ephedrine (C) Increase preload (D) Give prophylactic atropine
(C) Increase preload Preload is essential when administering spinal and epidural anesthesia. Giving a fluid bolus improves preload in light of a sympathetic blockade. When signifcant bradycardia occurs following administration of local anesthetic, give ephedrine and atropine in sequence. These measures will help avoid cardiac arrest.
Which factors are not complications associated with massive blood transfusion? Select (2) two (A) Serum K + 5.5 (B) Core temperature 35.5 °C (C) Increased 2,3 DPG (D) Decreased 2,3 DPG (E) Ionized Ca + 1.25 mmol/L
(C) Increased 2,3 DPG (E) Ionized Ca + 1.25 mmol/L Decreased 2,3 DPG is a complication associated with massive transfusion, not increased 2,3 DPG. Hypocalcemia is also associated with massive transfusion. This ionized calcium value is normal. Hyperkalemia (A), hypothermia (B), and decreased 2,3 DPG (D) are all complications of massive blood transfusion.
Injecting local anesthetic at which site is associated with the greatest risk of systemic absorption? (A) Brachial plexus (B) Paracervical (C) Intercostal (D) Caudal
(C) Intercostal Intercostal nerve blocks result in the highest blood levels of any block in the body. In general, more vascular locations result in greater risk o systemic absorption. The risk declines as follows: Intercostal > caudal > paracervical > epidural > brachial plexus > sciatic > subcutaneous.
Which feature of a pediatric endotracheal tube will have greatest influence on work of breathing? (A) External diameter (B) Length (C) Internal diameter (D) Curvature
(C) Internal diameter The internal diameter of the tube has the greatest influence on resistance.
What brachial plexus approach is indicated for a patient undergoing a shoulder surgery? (A) Supraclavicular (B) Infraclavicular (C) Interscalene (D) Axillary
(C) Interscalene Surgeries distal to the mid-humerus employ supraclavicular, infraclavicular, and axillary blocks. The interscalene block is used for surgeries proximal to the humerus including the shoulder.
A patient states that their feet are numb following administration of an epidural test dose. What is the most likely cause? (A) Intravascular injection (B) Local anesthetic toxicity (C) Intrathecal injection (D) Normal response to a test dose
(C) Intrathecal injection The test dose determines correct epidural needle placement. Inadvertent injection of an epidural test dose into the intrathecal space results in signs and symptoms consistent with a spinal anesthetic. Intravascular injection is demonstrated by tachycardia.
What is a disadvantage of the Bain circuit? (A) Increases circuit bulk (B) Partial warming of inspiratory gas (C) Kinking of the fresh gas inlet tube (D) Requires low fresh gas low
(C) Kinking of the fresh gas inlet tube Rationale: A disadvantage o this circuit is the chance o kinking or disconnection o the resh gas inlet. Periodic check o the inner tubing is set to prevent this complication.
Which of the following form the lumbar plexus? (A) L1-3 and T10 (B) L1-4 and T10 (C) L1-4 and T12 (D) L1-3 and T12
(C) L1-4 and T12 L1-4 and T12 ventral rami form the lumbosacral plexus.
Where does the spinal cord end in a 5-year-old? (A) L1 (B) L2 (C) L3 (D) L4
(C) L3 The spinal cord ends at L1 in adults and L3 in children.
A patient having which of the following conditions is LEAST likely to develop disseminated intravascular coagulation? A. Pregnancy-induced hypertension B. Placenta abruption C. Placenta previa (bleeding) D. Amniotic fluid embolism E. Dead fetus syndrome
(C) Laboratory diagnosis of DIC is based on the demonstration of consumption of procoagulants (decrease in fibrinogen, decrease in platelet count, and prolongation of prothrombin time [PT] and activated partial thromboplastin time [aP'IT]), demonstration of circulating fibrin-fibrinogen degradation products, and indirect evidence of obstruction of the microcirculation. DIC is associated with the following obstetric conditions: placental abruption, dead fetus syndrome, amniotic fluid embolism, gram-negative sepsis, and severe pregnancy-induced hypertension. Placental abruption is the most common cause of DIC in pregnant patients. If you look at severe placenta abruptions (where the abruption is large enough to cause fetal death), about 30% of patients will develop DIC within 8 hours of the abruption. Patients with placenta previa who are bleeding do not develop DIC because the blood loss does not induce a coagulopathy.
When dosing medications for obese patients, what is the best weight parameter to use? (A) Total body weight (B) Ideal body weight (C) Lean body weight (D) Total body mass index
(C) Lean body weight High plasma concentrations result when administering IV medications to obese patients based on total body weight. This is due to poor blood flow to fat. Lean body weight is the parameter when dosing medications for obese patients. Lean body weight does not include fat weight. Neither ideal body weight nor body mass index is used to calculate IV medications for obese patients.
Where is the best location to monitor blood pressure or patients undergoing right shoulder arthroscopy in the beach chair position? (A) Right lower extremity (B) Left lower extremity (C) Left upper extremity (D) Right upper extremity
(C) Left upper extremity The upper extremity is used to monitor non invasive blood pressure or this case. There is a significant difference (40 mmHg) when using the lower extremity. Hypotension although common or this procedure and position, needs to be minimized to avoid low cerebral perfusion
The "snap" felt just before entering the epidural space represents passage through which ligament? A. Anterior longitudinal ligaments B. Posterior longitudinal ligaments C. Ligamentum flavum D. Supraspinous ligament E. Interspinous ligament
(C) Ligamentum flavum The structures that are traversed by a needle placed in the midline prior to the epidural space are as follows: skin (Le., subcutaneous tissue), supraspinous ligament, interspinous ligament, and ligamentum ftavum. The ligamentum ftavum is tough and dense and often perceived as a "snap." The anterior and posterior longitudinal ligaments bind the vertebral bodies together. See also explanation and diagram in question 870
During the preoperative airway exam, you visualize the soft palate, faces, and uvula. How would you classify the patient's airway? (A) Mallampati I (B) Mallampati III (C) Mallampati II (D) Mallampati IV
(C) Mallampati II The Mallampati (MP) score correlates the ease of laryngoscopy and tracheal intubation with the ability to visualize oropharyngeal structures. Visualization of the soft palate, faces, uvula, and tonsillar pillars identifies the airway as a MP I. Visualization of the soft palate and base of the uvula is a MP III. No visualization of the soft palate identifes the airway as a MP IV.
A 56-year-old patient is brought to the operating room (OR) for elective replacement of a stenotic aortic valve. An awake 20-gauge arterial catheter is placed into the right radial artery and is then connected to a transducer located at the same level as the patient's left ventricle. The entire system is zeroed at the transducer. Several seconds later the patient raises both arms into the air such that his right wrist is 20 cm above his heart. As he is doing this, the blood pressure on the monitor reads 120/80. What would this patient's true blood pressure be at this time? A. 140/100 mm Hg B. 135/95 mm Hg C. 120/80 mm Hg D. 105/65 mm Hg E. 100/60 mm Hg
(C) Modern electronic blood pressure monitors are designed to interface with electro-mechanical transducer systems. These systems do not require extensive technical skill on the part of the anesthesia provider for accurate usage. A static zeroing of the system is built into most modern electronic monitors. Thus, after the zeroing procedure is accomplished, the system is ready for operation. The system should be zeroed with the reference point or the transducer at the approximate level of the aortic root, eliminating the effect of the fluid column of the system on arterial blood pressure readings.
Which selection pertains to a closed waste gas scavenging system with active scavenging? (A) Must have a negative-pressure relief valve (B) Must have both a negative and positive pressure relief valve (C) Must have a positive-pressure relief valve (D) Requires no pressure relief valves
(C) Must have a positive-pressure relief valve A closed waste gas scavenging system is closed to the outside atmosphere and requires negative and positive pressure relief valves that shield the patient from the negative pressure o the vacuum system and positive pressure from an impediment in the scavenging tubing.
A lumbar epidural is placed in a 24-year-old gravida 1, para 0 parturient with myasthenia gravis for labor. Select the true statement regarding neonatal myasthenia gravis. A. The newborn is usually affected. B. The newborn is affected by maternal immunoglobulin M (lgM) antibodies. C. The newborn may require anticholinesterase therapy for up to 3 weeks. D. The newborn will need lifelong treatment. E. Only female newborns are affected.
(C) Myasthenia gravis (MG) is an autoimmune neuromuscular disease in which immunoglobulin G (lgG) antibodies are directed against the acetylcholine receptors in skeletal muscle, causing patients to present with general muscle weakness and easy fatigability. Smooth muscle and cardiac muscle are not affected. About 10% to 20% of newborns born to mothers with MG are transiently affected because the IgG antibody is transferred through the placenta. Neonatal MG is characterized by muscle weakness (e.g., hypotonia, respiratory difficulty) and may present within the first 4 days of life (80% present within the first 24 hours). Anticholinesterase therapy may be required for a few weeks until the maternal IgG antibodies are metabolized.
Normal resting myocardial Ó consumption is: A. 2.0 mU/1OO g/min B. 3.5 mU/100 g/min C. 10 mL/IOO g/min D. 15 mL/I00 g/min E. 25 mLI/ 100 g/min
(C) Myocardial preservation is achieved during cardiopulmonary bypass primarily by infusing cold (4°C) cardioplegia solutions containing potassium chloride 20 mEqlL. This rapidly produces hypothermia of the cardiac muscle and a flaccid myocardium. In the normal contracting muscle at 37°C, myocardial Ó consumption is approximately 8 to 10 mLIlOO g1min. This is reduced in the fibrillating heart at 22°C to approximately 2 mUI00 g1min. Myocardial Ó consumption of the electromechanically quiescent heart at 22°C is less than 0.3 mUI00 g1min
Which of the following statements is true regarding airway blocks? (A) Topical lidocaine may produce methemoglobinemia. (B) 4% lidocaine is injected into the trachea upon inspiration. (C) Nerve blocks of the airway pose risk for aspiration. (D) Local anesthesia to the mouth and pharynx blocks nerve transmission from the superior laryngeal nerve.
(C) Nerve blocks of the airway pose risk for aspiration Benzocaine is linked to methemoglobinemia. For transtracheal blocks, local anesthetic is injected into the trachea during end expiration. The trigeminal and glossopharyngeal nerves innervate the airway including the anterior 2/3 of the tongue.
Gabapentin is most helpful in treating which type of pain? (A) Acute somatic pain (B) Deep visceral pain (C) Neuropathic pain (D) Chronic arthritic joint pain
(C) Neuropathic pain Gabapentin and other anticonvulsants are most helpful when used in the treatment neuropathic pain.
What are three functions of the hanger yoke? (A) Shuts of nitrous oxide when oxygen pressure falls below 20 psi, provides a gas tight seal, and ensures unidirectional low (B) Monitors inspired oxygen level, reduces pressure to 45-47 psi, and ensures unidirectional low (C) Orients cylinders, provides a gas tight seal, and ensures unidirectional flow (D) Ensures at least 25% oxygen is given when using nitrous oxide, provides a gas tight seal, and ensures unidirectional low
(C) Orients cylinders, provides a gas tight seal, and ensures unidirectional flow. Part one of A refers to the oxygen shut of valve, parts one and two of B refer to the oxygen analyzer and the pressure regulator, part one of D refers to the hypoxic guard.
What is the definition of persistent postsurgical pain? (A) Pain resulting from outpatient surgery sufficient to require inpatient care (B) Pain for > 1-2 weeks following surgery (C) Pain for > 1-2 months following surgery (D) Pain for > 1 year following surgery
(C) Pain for > 1-2 months following surgery Chronic pain persisting beyond 4-8 weeks following surgery defines persistent postsurgical pain.
Which oxygen analyzer works by using the oxygen molecules' unique attraction into magnetic fields? (A) Electrogalvanic cell (B) Polarographic electrode (C) Paramagnetic oxygen sensor (D) Fluorescence quenchin
(C) Paramagnetic oxygen sensor A creates its own electric current by using a lead anode and either a gold or silver anode. B creates its own electric current by using a silver anode and platinum cathode. D uses the fluorescence caused by a molecule emitting light in response to being energized.
Which is an example of sensation without stimulus? (A) Temporal summation (B) Dynamic allodynia (C) Paresthesia (D) Analgesia
(C) Paresthesia Paresthesia is the spontaneous perception o an abnormal sensation.
Which is an example of sensation without stimulus? (A) emporal summation (B) Dynamic allodynia (C) Paresthesia (D) Analgesia
(C) Paresthesia Rationale: Paresthesia is the spontaneous perception of an abnormal sensation.
Cleft palate, micrognathia, glossoptosis, and congenital heart disease are key characteristics of which syndromes? (A) Treacher Collins (B) VATER (C) Pierre-Robin (D) Prader-Willi
(C) Pierre-Robin The listed characteristics are those of Pierre-Robin syndrome. Glossoptosis is an important characteristic as it created a ball-valve effect in the airway that can result in asphyxiation.
Which of the following factors has the greatest effect on the level of spinal anesthesia? (A) Age (B) Patient height (C) Position of patient during injection (D) Drug volume
(C) Position of patient during injection. The most important factors affecting the level of spinal anesthesia are solution baricity, drug dose, injection site, and patient position both during and directly after injection. In general, higher levels are obtained with higher doses, higher sites of injection, and hypobaric solutions (when in head up position).
Which of the following local anesthetics should be avoided in a glucose-6-phosphate dehydrogenase (G6PD) defciency? (A) Ropivacaine (B) Etidocaine (C) Prilocaine (D) Tetracaine
(C) Prilocaine Both prilocaine and lidocaine have been associated with red cell hemolysis in patients with G6PD de ciency. T e enzyme G6PD, catalyzes the initial step in the hexose monophosphate shunt which protects red blood cells against oxidative injury by producing NADPH. Hemolysis is triggered when older red blood cells that are de cient in the enzyme are destroyed when exposed to drugs such as prilocaine with high redox potential. Ref: Butterworth, J.F., Mackey, D.C.,
Which local anesthetic is metabolized by 0-toluidine? (A) Nesacaine (B) Cocaine (C) Prilocaine (D) Mepivacaine
(C) Prilocaine Prilocaine is the only amide local anesthetic not metabolized by P-450 microsomal enzymes. Ester local anesthetics nesacaine is metabolized by pseudocholinesterase whereas N-methylation and ester hydrolysis is responsible or cocaine metabolism. Mepivacaine is metabolized by P-450 microsomal enzymes.
Which of the following would result in the greatest decrease in the arterial hemoglobin saturation (Sp02) value measured by the dual-wave-Iength pulse oximeter? A. Intravenous injection of indigo carmine. B. Intravenous injection of indocyanine green. C. Intravenous injection of methylene blue. D. Presence of elevated bilirubin. E. Presence of fetal hemoglobin.
(C) Pulse oximeters estimate arterial hemoglobin saturation (Sáo) by measuring the amount of light transmitted through a pulsatile vascular tissue bed. Pulse oximeters measure the alternating current (AC) component of light absorbance at each of two wavelengths (660 and 940 nm) and then divides this measurement by the corresponding direct current component. Then the ratio (R) of the two absorbance measurements is determined by the following equation. U sing an empirical calibration curve that relates arterial hemoglobin saturation to R, the actual arterial hemoglobin saturation is calculated. Based on the physical principles outlined above, the sources of error in Sp02 readings can be easily predicted. Pulse oximeters can function accurately when only two hemoglobin species, oxyhemoglobin and reduced hemoglobin, are present. If any light-absorbing species other than oxyhemoglobin and reduced hemoglobin are present, the pulse oximeter measurements will be inaccurate. Fetal hemoglobin has minimal effect on the accuracy of pulse oximetry, because the extinction coefficients for fetal hemoglobin at the two wavelengths used by pulse oximetry are very similar to the corresponding values for adult hemoglobin. In addition to abnonnal hemoglobins, any substance present in the blood that absorbs light at either 660 or 940 nm, such as intravenous dyes used for diagnostic purposes, will affect the value of R, making accurate measurements of the pulse oximeter impossible. These dyes include methylene blue and indigo cannine. Methylene blue has the greatest effect on Sáo measurements because the extinction coefficient is so similar to that of oxyhemoglobin.
What mechanism results in the greatest amount of heat loss in the operating room? (A) Convection (B) Evaporation (C) Radiation (D) Conduction
(C) Radiation Radiation (60%) results in the most heat lost in the operating room. Evaporation, convection, and conduction follow.
A patient with two peripheral intravenous (PIV) lines is undergoing general endotracheal anesthesia (GETA) for an orthopedic procedure. A recent lab value reveals a serum potassium level of 2.9 mEq/L. Which intervention is appropriate for this patient? (A) Administer IV replacement K + in dextrose solutions. (B) Maintain ETCO2 levels between 25-30 mmHg. (C) Reduce the rocuronium redose by 25-50%. (D) Administer IV replacement K + 20 mEq IV in 0.9% NS over 1 hour.
(C) Reduce the rocuronium redose by 25-50%. Increased sensitivity to neuromuscular blockers is common in patients with hypokalemia, and, there ore, dosages should be reduced by 25-50%. A is incorrect because dextrose containing solutions will result in hyperglycemia and secondary insulin secretion, thus worsening hypokalemia. B is incorrect because hyperventilation will cause further decreases in plasma K+. D is incorrect because peripheral replacement of K+ should not exceed 8 mEq/h. Rapid replacement (i.e., 10-20 mEq/L) requires central venous administration.
The afferent input for somatosensory evoked potentials (SSEPs) is carried through which spinal cord tract? A. Spinocerebellar B. Spinothalamic C. Dorsal columns D. Corticospinal E. Vestibulospinal
(C) SSEPs are voltage signals that appear in response to electrical stimulation of peripheral nerves. The impulse elicited by electrical stimulation of a peripheral nerve ascends the ipsilateral dorsal column of the spinal cord, decussates in the medulla oblongata, and is ultimately recorded on the contralateral somatosensory cortex of the brain. SSEPs are composed of negative and positive voltage deflections with specific latencies and amplitudes. In general, the earlier deflections represent impulses and synapses within the spinal cord or brainstem, whereas the later impulses represent thalamic and/or cortical synapses. Intraoperative monitoring of SSEPs provides the ability to assess the integrity of the peripheral nerve (e.g., posterior tibial nerve, dorsal columns, brainstem, medial lemniscus, internal capsule, and contralateral somatosensory cortex) (Miller: Anesthesia, ed 5, pp 1336-1337). 730
Which of the following peripheral nerve block(s) would provide the most effective analgesia for a total knee arthroplasty? (A) Femoral nerve block (B) Femoral nerve block and obturator nerve block (C) Sciatic nerve block and psoas block (D) Sciatic and popliteal block
(C) Sciatic nerve block and psoas block Patients undergoing total knee arthroplasty experience significant postoperative pain. Surgical anesthesia for knee procedures utilizing a tourniquet can be provided through blockade of the femoral, lateral femoral cutaneous, obturator, and sciatic nerve
An injection of 0.5% ropivacaine is placed into the brachial plexus via the interscalene approach. Which of the following is most likely to be spared? (A) Sensation of the radial side of the forearm (B) Sensation of the medial upper arm (C) Sensation of half of the fourth and all of the fifth fingers (D) Sensation of the palmar surface of the first three fingers.
(C) Sensation of half of the fourth and all of the fifth fingers The interscalene block of the brachial plexus is the most proximal approach to the brachial plexus and idea or shoulder surgery with advantages of clear landmarks and a low risk of pneumothorax because of the distance to the dome of the pleura. his approach can be used for forearm and hand surgery; however, blockade of the inferior trunk is typically incomplete. The inferior trunk provides innervation to C8 and 1. Supplementation at the site of the ulnar nerve can assist with providing coverage for that distribution.
How would you classi y a patient with repeated blood pressure measurements ranging rom 160/100 to 179/109? (A) High normal (B) Stage 1 hypertension (C) Stage 2 hypertension (D) Stage 3 hypertension
(C) Stage 2 hypertension Stage two or moderate hypertension is de ned as systolic pressure between 160 to 179 mmHg and diastolic pressure between 100 to 109 mmHg
Which is least adaptive in an infant as compared to an adult? (A) Heart rate (B) Cardiac output (C) Stroke volume (D) Chest wall
(C) Stroke volume Stroke volume in neonates and infants is less adaptive than in an adult. Increasing heart rate is the means of increasing cardiac output.
Which statement is true regarding ultrasound for peripheral nerve blocks? (A) Structures that appear white on the ultrasound screen are hypoechoic. (B) Low frequencies are used for peripheral nerve blocks. (C) Structures that appear white on the ultrasound screen are hyperechoic. (D) High- frequency transducers offer a low resolution picture.
(C) Structures that appear white on the ultrasound screen are hyperechoic. Hypoechoic refers to dark structures on the ultrasound screen. Higher frequencies are used or peripheral nerve blocks, whereas lower frequencies are used for spinal and epidural anesthesia when ultrasound technology is employed. High- frequency transducers provide high resolution pictures but poor tissue penetration. Low- frequency transducers allow or deeper tissue penetration.
How would postoperative pain localized to the site of skin incision be classified? (A) Visceral pain (B) Deep somatic pain (C) Superficial somatic pain (D) Referred pain
(C) Superficial somatic pain This is an example of acute superficial somatic pain.
Which nerve is blocked by injection through the thyrohyoid membrane to anesthetize the area between the vocal cords and the epiglottis? (A) Hypoglossal (B) Recurrent laryngeal (C) Superior laryngeal (D) Glossopharyngeal
(C) Superior laryngeal Sensory innervation of the airway below the epiglottis is supplied by the vagus nerve. The internal branch of the superior laryngeal nerve provides sensation from the epiglottis to the vocal cords.
A 68-year-old woman is to undergo foot surgery under spinal anesthesia. Which of the following statements concerning the immediate physiologic response to the surgical incision is true? A. The cardiovascular response to stress will be blocked, but the adrenergic response will not B. The adrenergic response to stress will be blocked, but the cardiovascular response will not C. Both the adrenergic and cardiovascular responses will be blocked D. Neither the adrenergic or cardiovascular response will be blocked E. The cardiovascular response will be blocked but the adrenergic response will be augmented.
(C) Surgical trauma includes a wide variety of physiologic responses. General anesthesia has no or only a slight inhibitory effect on endocrine and metabolic responses to surgery. Regional anesthesia inhibits the nociceptive signal from reaching the CNS and, therefore, has a significant inhibitory effect on the stress response, including adrenergic, cardiovascular, metabolic, immunologic, and pituitary. This effect is most pronounced with procedures on the lower part of the body and less with major abdominal and thoracic procedures. The variable effect is probably due to unblocked afferents, Le., vagal, phrenic, or sympathetic.
What level of neural blockade is needed for analgesia during the first stage of labor? (A) T10-L1 motor level (B) T10-S4 sensory level (C) T10-L1 sensory level (D) T10-S4 motor level
(C) T10-L1 sensory level A sensory level 10-L1 is needed for adequate analgesia during the rst stage of labor. During the second stage o labor additional sensory levels 10-S4 require neural blockade.
How do transient neurologic symptoms ( TNS) differ from cauda equina syndrome? (A) TNS persists for several weeks following surgery. (B) Cauda equina syndrome disappears within 10 days following surgery. (C) TNS symptoms spontaneously disappear. (D) Cauda equina syndrome symptoms include severe radicular back pain.
(C) TNS symptoms spontaneously disappear Cauda equina syndrome is a persistent condition that results in lower extremity weakness, bowel and bladder dysfunction. TNS occurs within 24 hours of surgery. Mild to severe radicular back pain results, but symptoms spontaneously disappear.
Which color of nail polish would have the greatest effect on the accuracy of dual-wavelength pulse oximeters? A. Red B. Yellow C. Blue D. Green E. White
(C) The accurate function of dual-wavelength pulse oximeters is altered by nail polish. Because blue nail polish has a peak absorbance similar to that of adult deoxygenated hemoglobin (near 660 nm), blue nail polish has the greatest effect on the Sp02 reading. Nail polish causes an artifactual and fixed decrease in the Sp02 reading by these devices.
Uptake of sevoflurane from the lungs during the first minute of general anesthesia is 50 mL. How much sevoflurane would be taken up from the lungs between the 16th and 36th minutes? A. 25 mL B. 50 mL C. 100 mL D. 200mL E. 500 mL
(C) The amount of volatile anesthetic taken up by the patient in the first minute is equal to that amount taken up between the squares of any two consecutive minutes. Accordingly, 50 I11L would be taken up between the 16th (4 X 4) and 25th (5 X 5) minute, and another 50 mL would be taken up between the 25th and 36th (6 X 6) minute (Miller: Anesthesia, ed 5, p 87).
What is the normal oxygen consumption in the brain per minute? A. 0.5 mUI00 g brain tissue B. 2.0 mUI00 g brain tissue C. 3.5 mUI00 g brain tissue D. 7.5 mLllOO g brain tissue E. 10 mL/l 00 g brain tissue
(C) The brain is an obligate aerobe, as it cannot store oxygen. Under normal circumstances, there is a substantial safety margin in that the delivery of oxygen is considerably greater than demand. Oxygen consumption is in the range of 3 to 5 mUIOO g of brain tissue/min, whereas the delivery of oxygen is approximately 50 mL bloodliOO g brain tissue/min
The deep peroneal nerve innervates the : A. Lateral aspect of the dorsum of the foot B. Entire dorsum of the foot C. Web space between the great toe and the second toe D. Web space between the third and fourth toes E. Medial aspect of the dorsum of the foot
(C) The deep peroneal nerve innervates the short extensors of the toes and the skin of the web space between the great and second toe. The deep peroneal nerve is blocked at the ankle by infiltration between the tendons of the anterior tibial and extensor hallucis longus muscle.
A 72-year-old patient undergoing resection of an astrocytoma in the sitting position suddenly develops hypotension. Air is heard on the precordial Doppler ultrasound. Each of the following therapeutic maneuvers to treat VAE is appropriate EXCEPT A. Discontinue N20 B. Apply jugular venous pressure C. Implement positive end-expiratory pressure (PEEP) D. Administer epinephrine to treat hypotension E. Flood the surgical wound with saline
(C) The general approach to treating patients following venous air embolism (VAE) is to (I) stop further air entrainment, (2) aspirate entrained air, (3) prevent expansion of existing air, and (4) support cardiovascular function. Cessation of subsequent air entrainment is achieved by flooding the surgical field with irrigation fluid. Additionally, noncollapsible veins can be sealed using electrocautery, vessel ligation, or bone wax. Neck veins can be compressed as a means of increasing jugular venous pressure, which mitigates or prevents further air entry and helps localize the source of air. A multiorificed right atrial catheter, placed before the event, is the most effective means of aspirating VAE. In order to prevent expansion of the V AE, nitrous oxide is immediately discontinued. Cardiovascular function is supported using inotropes, vasopressors, and intravenous fluids as indicated. Of the response options provided, PEEP is the least correct answer. Approximately 20% to 30% of humans have a probe patent foramen ovale. Initiation of PEEP may increase the risk of paradoxical embolism or decrease venous effluent from the calvarium, resulting in increased CBV and ICP.
Select the one true statement concerning phantom limb pain. A. Most phantom limb pain becomes more severe with time B. Most amputees do not experience phantom limb pain C. Nerve blocks are commonly used to treat phantom limb pain D. Trauma amputees have a higher incidence of phantom limb pain than nontrauma amputees E. The incidence of phantom limb pain increases with more distal amputations.
(C) The incidence of phantom limb pain is estimated to be 60% to S5%. The incidence of phantom limb pain does not differ between traumatic and nontraumatic amputees. The incidence of phantom pain increases with more proximal amputation. Although very difficult to treat, nerve blocks are commonly used in an attempt to treat phantom pain. These include trigger point injections, peripheral and central nerve blocks, and sympathetic blocks.
Morphine is not used routinely for labor epidurals because it: A. Increases uterine tone B. Causes excessive neonatal respiratory depression. C. Has a slow onset. D. Decreases uterine blood flow E. Adversely affects FHR variability
(C) The main reason morphine is not routinely used for labor epidurals is its long onset time (40 to 50 minutes after 4 to 5 mg epidural morphine). Morphine has little effect on uterine tone, uterine blood flow, or FHR. The doses used epidurally do not cause significant neonatal depression.
Which of the following is the most important disadvantage of interscalene brachial plexus block compared with other approaches? A. Not suitable for operations on the shoulder B. Large volumes of local anesthetics required C. Frequent sparing of the ulnar nerve D. Frequent sparing of the musculocutaneous nerve E. High incidence of pneumothorax.
(C) The major disadvantage of the interscalene block for hand and forearm surgery is that blockade of the inferior trunk (C8-Tl) is often incomplete. Supplementation of the ulnar nerve is often required. The risk of pneumothorax is quite low, but blockade of the ipsilateral phrenic nerve occurs in up to 100% of blocks. This can cause respiratory compromise in patients with significant lung disease.
The minimum macroshock current required to elicit ventricular fibrillation is A. 1 milliamp B. 10 milliamp C. 100 milliamp D. 500 milliamp E. 5000 milliamp
(C) The minimum macroshock current required to elicit ventricular fibrillation is 100 milliamps.
Which of the following is the most sensitive means of detecting venous air embolism (VAE)? A. Electroencephalography (EEG) B. Pulmonary artery catheter C. Transesophageal echocardiography D. Mass spectrometry E. Right atrial catheterization
(C) The most common complications associated with the surgical sitting position include venous air embolism (YAE), paradoxical YAE, cardiovascular instability, pneumocephalus, subdural hematoma, peripheral neuropathy, and quadriplegia (quadriplegia is possibly caused by compression ischemia of the cervical spinal cord in patients with aberrant spinal cord blood supply). YAE occurs when air is entTained into open veins in the presence of negative intraluminal pressures (i.e., negative with respect to atmospheric pressure). Significant YAE can result in reduced cardiac output and profound hypoxia. Current devices used to detect YAE include the transesophageal echocardiograph, Doppler ultrasound, pulmonary artery catheter, mass spectrometer (to monitor changes in PECO, and PEN,), right atrial catheter, and esophageal stethoscope (to listen for a "mill wheel" cardiac murmur). The most sensitive means of diagnosing YAE include transesophageal echocardiography or precordial Doppler monitoring.
A 22-year-old patient who sustained a closed head injury is brought to the operating room (OR) from the ICU for placement of a dural bolt. Hemoglobin has been stable at 15 g/elL. Blood gas analysis immediately before induction reveals a Páo of 120 mm Hg and an arterial saturation of 100%. After induction the Páo rises to 150 mm Hg and the saturation remains the same. How has the oxygen content of this patient's blood changed? A. It has increased by 10% B. It has increased by 5% C. It has increased by less than 1% D. Can not be determined without Pacó E. Can not be determined without pH
(C) The oxygen content of blood can be calculated with the following formula: Ó content = (1.39 X hemoglobin X arterial saturation) + 0.003 X Páo First oxygen content = (1.39 X 15 X 1.0) + 0.003 X 120 = 21.21 mL/dL Second oxygen content = (1.39 X 15 X 1.0) + 0.003 X 150 = 21.30 mL/dL
Each of the following will cause erroneous readings by dual-wavelength pulse oximeters EXCEPT A. Carboxyhemoglobin B. Methylene blue C. Fetal hemoglobin D. Methemoglobin E. Nail polish
(C) The presence of hemoglobin species other than oxyhemoglobin can cause erroneous readings by dual-wavelength pulse oximeters. Hemoglobin species such as carboxyhemoglobin and methemoglobin, dyes such as methylene blue and indocyanine green, and some colors of nail polish will cause erroneous readings. Because the absorption spectrum of fetal hemoglobin is similar to that of adult oxyhemoglobin, fetal hemoglobin does not significantly affect the accuracy of these types of pulse oximeters. High levels of bilirubin have no significant effect on the accuracy of dual-wavelength pulse oximeters, but may cause falsely low readings by nonpulsatile oximeters.
When intracranial hypertension exists, the main compensatory mechanism from the body is A. Increased absorption at the intracranial arachnoid villi B. Increased absorption of cerebrospinal fluid (CSF) in the spinal arachnoid villi C. Shifting of CSF into the spinal subarachnoid space D. Reduction of cerebral blood volume (CBV) from compression of cerebral veins E. Decreased production of CSF at the choroid plexus.
(C) The primarily compensatory mechanism for intracranial hypertension is translocation of CSF from the intracranial vault into the spinal subarachnoid space.
A 61-year-old male patient with idiopathic hypertrophic subaortic stenosis is scheduled for left ventricular myectomy under general anesthesia. Which of the following anesthetics would provide the most stable hemodynamics in this patient? A. N2O-narcotic B. Ketamine C. Halothane D. Sevoflurane E. Isoflurane
(C) The primary goal in the anesthetic management of patients with idiopathic hypertrophic subaortic stenosis is to reduce the gradient across the left ventricular outflow obstruction. In general, drugs that increase myocardial contractility or reduce preload or afterload increase the magnitude of this obstruction. Halothane is an ideal volatile anesthetic agent for maintaining anesthesia in these patients because it is a direct myocardial depressant, but it does not decrease systemic vascular resistance. Both of these characteristics are beneficial for these patients because they do not increase the magnitude of left ventricular outflow obstruction. Should hypotension develop, phenylephrine, a pure (X-adrenergic receptor agonist, should be administered to increase arterial blood pressure because it increases systemic vascular resistance, thereby reducing left ventricular outflow obstruction (Stoelting: Basics of Anesthesia.
The "snap" felt just before entering the epidural space represents passage through which ligament? A. Anterior longitudinal ligaments B. Posterior longitudinal ligaments C. Ligamentum flavum D. Supraspinous ligament E. Interspinous ligament
(C) The structures that are traversed by a needle placed in the midline prior to the epidural space are as follows: skin (Le., subcutaneous tissue), supraspinous ligament, interspinous ligament, and ligamentum ftavum. The ligamentum ftavum is tough and dense and often perceived as a "snap." The anterior and posterior longitudinal ligaments bind the vertebral bodies together.
Which of the following factors is LEAST responsible for killing bacteria in anesthesia machines? A. Metallic ions B. High Ó concentration C. Anesthetic gases (at clinical concentrations) D. Shifts in humidity E. Shifts in temperature
(C) There is considerable controversy regarding the role of bacterial contamination of anesthesia machines and equipment in cross-infection between patients. The incidence of postoperative pulmonary infection is not reduced by the use of sterile disposable anesthetic breathing circuits (as compared with the use of reusable circuits that are cleaned with basic hygienic techniques). Furthermore, inclusion of a bacterial filter in the anesthesia breathing circuit has no effect on the incidence of cross-infection. Clinically relevant concentrations of volatile anesthetics have no bacteriocidal or bacteriostatic effects. Low concentrations of volatile anesthetics, however, may inhibit viral replication. Shifts in humidity and temperature in the anesthesia breathing and scavenging circuits are the most important factors responsible for killing bacteria. In addition, high Ó concentration and metallic ions present in the anesthesia machine and other equipment have a significant lethal effect on bacteria. Acid-fast bacilli are the most resistant bacterial form to destruction. Nevertheless, there has been no case documenting transmission of tuberculosis via a contaminated anesthetic machine from one patient to another. When managing patients who can potentially cause cross-infection of other patients (e.g., patients with tuberculosis, pneumonia, or known viral infections, such as acquired immune deficiency syndrome [AIDS]) a disposable anesthetic breathing circuit should be used and nondisposable equipment should be disinfected with glutaraldehyde (Cidex). Sodium hypochlorite (bleach), which destroys the human immunodeficiency virus, should be used to disinfect nondisposable equipment, including laryngoscope blades, if patients with AIDS require anesthesia.
Which of the following does not define somatic nociceptive pain? (A) Transduction (B) Transmission (C) Thermal (D) Modulation
(C) Thermal Transduction, transmission, modulation, and perception are the processes involved with somatic nociceptive pain. Thermal, mechanical, or chemical stimuli result in an action potential via transduction.
What is the best means to avoid lung overdistension for obese ventilated patients? (A) Tidal volume 10-15 mL/kg (B) Tidal volume 12-15 mL/kg (C) Tidal volume 6-10 mL/kg (D) Tidal volume 4-8 mL/kg
(C) Tidal volume 6-10 mL/kg Methods to minimize overdistension of the lung in obese patients include increasing the ventilation rate, keeping the end-inspiratory pressure <30 cm H2O and using a tidal volume o 6-10 mL/kg.
The pressure gauge on a size "E" compressed-gas cylinder containing 02 reads 1600 psi. How long could 02 be delivered from this cylinder at a rate of 2 L/min? A. 90 minutes B. 140 minutes C. 250 minutes D. 320 minutes E. Cannot be calculated
(C) United States manufacturers require that all compressed-gas cylinders containing 0, for medical use be painted green. A compressed-gas cylinder completely filled with 0, has a pressure of approximately 2000 psi and contains approximately 625 L of gas. According to Boyle's law (see explanation to question 9) the volume of gas remaining in a closed container can be estimated by measuring the pressure within the container. Therefore, when the pressure gauge on a compressed-gas cylinder containing 0, shows a pressure of 1600 psi, the cylinder contains 500 L of 0 ,. At a gas flow of 2 Llmin, 0, could be delivered from the cylinder for approximately 250 minute.
Uterine blood flow at term pregnancy is A. 50 mL/min B. 250 mL/min C. 700 mL/min D. 1100 mL/min E. 1500 mL/min
(C) Uterine blood flow increases dramatically from 50 to 100 mL/min before pregnancy to about 700 to 900 mL/min at term (i.e., >1 unit of blood per minute). Ninety percent of the uterine blood flow at term goes to the intervillous spaces. Uterine blood flow is related to the perfusion pressure (uterine arterial pressure minus uterine venous pressure) divided by the uterine vascular resistance. Thus, factors that decrease uterine blood flow include systemic hypotension, aortocaval compression, uterine contraction, and vasoconstriction
Which clotting factor is the first to become inactivated shortly after a patient has begun warfarin therapy? (A) IV (B) V (C) VII (D) IX
(C) VII Because factor VII has the shortest half-life (4-6 hours), it is the first factor to become inactivated a ter a patient begins treatment with warfarin.
The term luxury perfusion refers to a situation that occurs in the brain when: A. Blood flow has resumed after a period of ischemia. B. Blood flow is directed from a normal region of the brain to an ischemic region. C. Vasoparalysis exists. D. The Robin Hood phenomenon exists. E. A zone of ischemic penumbra exists.
(C) Vasoparalysis exist. During acute focal cerebral ischemia, vasoparalysis results in impaired coupling between cerebral blood flow and metabolism. Consequently, cerebral blood flow is usually greater than cerebral metabolic rate and is passively associated with systemic arterial blood pressure. Under these circumstances, autoregulation and the reactivity of the cerebrovasculature to carbon dioxide is also disturbed. Thus, tight control of systemic arterial blood pressure is important in managing patients with focal ischemia, because cerebral perfusion is highly dependent on mean arterial blood pressure
Epidural use of which of the following opioids would result in the greatest incidence of delayed respiratory depression? A. Sufentanil B. Fentanyl C. Morphine sulfate D. Hydromorphone E. Meperidine
(C) Water-soluble drugs such as morphine have a higher potential for inducing delayed respiratory depression through cephalad migration in the CNS.
Which risk factors predispose patients to lower extremity neuropathy? Select (3) three (A) Hypertension (B) Obesity (C) thin body habitus (D) Cigarette smoking (E) Diabetes
(C) thin body habitus (D) Cigarette smoking (E) Diabetes Surgeries longer than 2 hours, positioning that involves the peroneal nerve, hypotension, elderly and vascular diseases are risk actors predisposing patients to lower extremity neuropathy.
The second-stage 02 pressure regulator delivers a constant 02 pressure to the rotameters of: A. 4 psi B. 8 psi C. 16 psi D. 32 psi E. 64 psi
(C) Ó and N20 enter the anesthesia machine from a central supply source or compressed-gas cylinders at pressures as high as 2200 psi (oxygen) and 750 psi (N20). First-stage pressure regulators reduce these pressures to approximately 45 psi. Before entering the rotameters, second-stage Ó pressure regulators further reduce the pressure to approximately 14 to 16 psi.
Which of the following would MOST likely be present after 24 hours of continued hyperventilation of an otherwise normal subject? (A)-PaCÓ < normal; CSF PCÓ < normal; CSF pH > normal; CBF < normal (B)-PaCÓ < normal; CSF PCÓ < normal; CSF pH > normal; CBF = normal (C)-PaCÓ < normal; CSF PCÓ < normal; CSF pH = normal; CBF = normal (D)-PaCÓ < normal; CSF PCÓ = normal; CSF pH = normal; CBF = normal
(C)-PaCÓ < normal; CSF PCÓ < normal; CSF pH = normal; CBF = normal. After 24 hours of continuous hyperventilation, the patient's PaCÓ would, by definition, be low. As the blood brain barrier (BBB) is freely permeable to CÓ, the PCÓ of the CSF would also be low; however, the pH of the CSF would have normalized. This would result in normal cerebral blood flow, despite continued hyperventilation.
A 22-year-old man with idiopathic hypertrophic sub aortic stenosis is undergoing an elective cholecystectomy under general anesthesia. Immediately after induction with thiopental, 5 mg/kg IV, the arterial blood pressure decreases from 140/82 to 70/40 mm Hg. What would be the most appropriate drug for treatment of hypotension in this patient? A. Ephedrine B. Mephentermine C. Isoproterenol D. Phenylephrine E. Epinephrine
(D) All of the drugs listed in this question except phenylephrine will increase the inotropic state of the myocardium, which can increase left ventricular outflow obstruction and decrease cardiac output. Phenylephrine, because it is a pure a-adrenergic receptor agonist, has minimal direct effects on myocardial contractility
A VVI pacemaker programmed to pace at a rate of 70 beats/min is noted on the preoperative ECG to pace at 61 beats/min. The most likely reason for this decrease in the pacing heart rate is A. Decreased atrial rate B. Third-degree heart block C. Trifascicular heart block D. Battery failure E. Normal variation
(D) The anesthetic management of patients with artificial cardiac pacemakers should include ECG monitoring to confirm continued function of the pulse generators as well as emergency equipment (e.g., electrical defibrillator, external converter magnet) and drugs (atropine, isoproterenol) to maintain an acceptable intrinsic heart rate if the artificial pacemaker malfunctions. Inadvertent displacement of the endocardial electrodes by catheters has not been reported when the electrodes have been in place for 4 weeks or more. In general, anesthetic drugs will not alter the function of artificial cardiac pacemakers. However, the stimulation thresholds for ventricular capture are not static values and can be altered by a number of physiologic events. For example, acute hypokalemia and respiratory alkalosis will increase the threshold for ventricular capture, which could result in a loss of pacing. In contrast, acute hyperkalemia and acidosis will decrease the threshold for ventricular capture, which may make the patient vulnerable to ventricular fibrillation. A decrease in the programmed rate of the pacemaker greater than 10% is a sign of battery failure. Should this occur, elective surgery should be canceled and a thorough evaluation of the pacemaker should be undertaken.
How much blood does a fully soaked laparotomy "lap" pad contain? (A) 10-20 mL (B) 25-50 mL (C) 50-100 mL (D) 100-150 mL
(D) 100-150 mL A fully soaked lap pad holds 100-150 ml o blood whereas a fully soaked 4 × 4 sponge holds approximately 10 mL.
What statement is true regarding digital nerve blocks? (A) A small gauge needle is inserted at the distal aspect of the selected digit. (B) 2-3 mL of lidocaine with epinephrine is used. (C) A small gauge needle is inserted at the medial and lateral borders of the base of the selected digit. (D) 2-3 mL of lidocaine is used
(D) 2-3 mL of lidocaine is used The digital block is performed by injecting 2-3 mL of a non-epinephrine containing local anesthetic solution at the base of the selected digit.
What is the normal aortic valve area? (A) 0.5-1.0 cm 2 (B) 1.0-1.5 cm 2 (C) 1.5-2.5 cm 2 (D) 2.5-3.5 cm 2
(D) 2.5-3.5 cm 2 The normal aortic valve has an area o 2.5 to 3.5 cm2.
The E-cylinder oxygen gauge pressure reads 850 psi: How many liters are remaining presuming that the E-cylinder was full at 2,000 psi and 660 L? (A) 300 L (B) 660 L (C) 240 L (D) 280 L
(D) 280 L Capacity L Service pressure psi = Contents remaining L Gauge pressure psi
Spinal anesthesia using tetracaine 12 mg is given for a patient undergoing a transurethral resection of the prostate. If you add epinephrine what is the longest anticipated duration? (A) 0.5 hour (B) 1 hour (C) 2 hours (D) 3 hours
(D) 3 hours Addition of epinephrine to tetracaine extends the duration of action from 2-4 hours.
How many liters per minute will the oxygen flush valve provide to the common gas outlet? (A) 10 L/min (B) 80-100 L/min (C) 20-30 L/min (D) 35-75 L/min
(D) 35-75 L/min The oxygen flush valve provides a high flow of oxygen directly to the common gas outlet at 35-75 L/min.
During the preoperative interview the patient shares that he/she performs light housework, plays golf once a week, and walks to the grocery store to get the newspaper. What is his/her metabolic equivalent (MET s)? (A) 1 MET (B) 2 MET s (C) 3 METs (D) 4 MET s
(D) 4 MET s Good functional capacity (4 ME s) includes those listed as well as heavy housework, short distance running, and climbing a flight of stairs without stopping. Poor functional capacity (1 ME ) includes basic activities of daily living and walking one to two blocks (<4 mph).
In which patient is spinal anesthesia contraindicated? (A) 30-year-old taking daily garlic (B) 50-year-old taking subcutaneous heparin injections (C) 25-year-old taking NSAIDS (D) 40-year-old who received thrombolytic therapy
(D) 40-year-old who received thrombolytic therapy Herbal remedies including garlic, ginkgo and ginseng increase the risk of bleeding, but are not contraindicated for regional anesthesia. No contraindication exists for patients taking aspirin, NSAIDs, or subcutaneous heparin. Thrombolytic therapy is an absolute contraindication or regional anesthesia.
Which patient requires a preoperative chest X-ray? (A) 55-year-old smoker undergoing a laparoscopic cholecystectomy (B) 65-year-old chronic stable bronchitic undergoing a carpal tunnel release (C) 60-year-old undergoing a transurethral resection of the prostate (D) 50-year-old undergoing a mitral valve replacement
(D) 50-year-old undergoing a mitral valve replacement. Preoperative chest X-rays are indicated or patients with acute or chronic symptomatic pulmonary dysfunction, cardiac conditions, or malignancies o the chest.
Which patient faces the greatest risk of complete cardiovascular collapse? (A) 75-year-old female with bilateral carotid artery disease with an aortic valve area of 1.1 cm2 undergoing left carotid endarterectomy (B) 82-year-old male with severe mitral regurgitation and severe tricuspid regurgitation with atrial fibrillation undergoing bowel resection for colon cancer (C) 67-year-old male with aortic valve area o 0.7 cm 2 undergoing left carotid endarterectomy (D) 59-year-old male with aortic valve area of 0.7 cm 2 undergoing colon resection for ischemic colon
(D) 59-year-old male with aortic valve area of 0.7 cm 2 undergoing colon resection for ischemic colon Aortic valve area of 0.7 cm2 is indicative of severe aortic stenosis. In severe aortic stenosis, changes in intravascular volume and decreases in a terload can lead to critical coronary ischemia. Patients with advanced aortic stenosis are particularly sensitive to hypotension. Aortic stenosis leads to left ventricular hypertrophy due to elevated left ventricular pressures. This, in turn, leads to both an increase in oxygen demand (due to hypertrophy and increased left ventricular systolic pressures) and a decrease in myocardial perfusion (due to left ventricular end-diastolic pressure). Abdominal surgeries in general, and colon resections (especially with ischemia which can lead to septic shock like states) in particular, are known or fluid shifts and decreases in a terload secondary to release of vasodilatory substances. Hypotension can quickly deteriorate to ventricular dysrhythmias and complete cardiovascular collapse necessitating cardiopulmonary resuscitation, even resulting in death.
What is the uterine blood flow at term? (A) 200-300 mL/min (B) 300-400 mL/min (C) 400-500 mL/min (D) 600-700 mL/min
(D) 600-700 mL/min The normal uterine blood flow in the nonpregnant female is 50 mL/min. At term the blood flow increases to approximately 10% of the cardiac output.
Estimate the total dIfference in cerebral blood flow if PaCO2 is decreased from 40 mmHg to 34 mmHg. Assume total brain weight is 1,400 grams. (A) 0-50 mL/min (B) 30-60 mL/min (C) 60-120 mL/min (D) 90-180 mL/min
(D) 90-180 mL/min The change in cerebral blood flow is 1 or 2 mL/100g/min for every 1 mmHg change in PaCO2. [6 x 2] x 14 = 168 ml/min
What should the activated clotting time be prior to initiation of cardiopulmonary bypass (CPB)? (A) <150 seconds (B) >200 seconds but <350 seconds (C) >350 seconds but <450 seconds (D) >400 seconds
(D) >400 seconds Initiation of cardiopulmonary bypass can begin after the AC is greater than 400-480 seconds. Failure to establish adequate anticoagulation will result in disseminated intravascular coagulation and formation of clots in the CPB pump.
Which phrase describes radiculopathy? (A) Abnormal sensation with or without a stimulus (B) Pain linked to noxious stimulation (C) Nerve distribution pain (D) Abnormal function of nerve roots
(D) Abnormal function of nerve roots The unpleasant or abnormal sensation with or without a stimulus is dysesthesia. Hyperalgesia is the increased response to noxious stimulation. Neuralgia describes pain associated with nerve distribution.
While receiving a blood transfusion during general anesthesia tachycardia and hypotension develop. What is the most likely cause? (A) Delayed hemolytic reaction (B) Anaphylactic reaction (C) Urticarial reaction (D) Acute hemolytic reaction
(D) Acute hemolytic reaction When a patient receives incompatible ABO blood, hemolytic reactions result. When patients are awake symptoms include chills, flank pain, nausea, and ever. Patients undergoing general anesthesia exhibit tachycardia hypotension, hemoglobinuria, and oozing. Delayed hemolytic reactions develop 2-21 days after the transfusion and are mild compared to the acute hemolytic reaction. Anaphylactic reactions occur in patients with IgA deficiency. Urticarial reactions are linked to plasma proteins.
A 100-kg patient is administered 40,000 units of heparin. Five minutes later the ACT was measured to be 182 seconds. What is the next step? (A) Proceed with cardiopulmonary bypass. (B) Wait 5 more minutes and recheck ACT . (C) Administer an additional 40,000 units of heparin. (D) Administer two units of fresh frozen plasma
(D) Administer two units of fresh frozen plasma The dose administered is appropriate (300-400 units/kg) to obtain an ACT necessary for initiating cardiopulmonary bypass, 400-800 seconds. typically, this therapeutic anticoagulation is obtained and varied within 3-5 minutes of administration. A patient may have an antithrombin III deficiency that renders them resistant to the e ects of heparin. Recombinant antithrombin III can be administered, but more commonly two units o fresh frozen plasma are administered to provide the antithrombin III necessary to achieve adequate anticoagulation.
A 22-year-old man with idiopathic hypertrophic sub aortic stenosis is undergoing an elective cholecystectomy under general anesthesia. Immediately after induction with thiopental, 5 mglkg IV, the arterial blood pressure decreases from 140/82 to 70/40 mm Hg. What would be the most appropriate drug for treatment of hypotension in this patient? A. Ephedrine B. Mephentermine C. Isoproterenol D. Phenylephrine E. Epinephrine
(D) All of the drugs listed in this question except phenylephrine will increase the inotropic state of the myocardium, which can increase left ventricular outflow obstruction and decrease cardiac output. Phenylephrine, because it is a pure a-adrenergic receptor agonist, has minimal direct effects on myocardial contractility
Vaporizers for which of the following volatile anesthetics could be used interchangeably with accurate delivery of the concentration of anesthetic set on the vaporizer dial? A. Halothane, sevoflurane, and isoflurane. B. Sevoflurane and isoflurane. C. Halothane and sevoflurane. D. Halothane and isoflurane. E. Sevofturane and desfturane.
(D) Also see explanation to question 16. The saturated vapor pressures of halothane and isoflurane are very similar (approximately 240 mm Hg at room temperature) and therefore could be used interchangeably in agent-specific vaporizers (see table in explanation for question 16) (Ehrenwerth: Anesthesia Equipment: Principles and Applications, pp 60-63; Stoelting: Basics of Anesthesia, ed 4, pp 134-136).
A 23-year-old parturient in the first trimester is brought to the OR for emergency appendectomy. General anesthesia is planned. An increased risk of congenital malformation associated with which drug has been suggested (but not proven) and almost always should be avoided? A. Thiopental B. Nitrous oxide C. Isoflurane D. Diazepam E. None of the above
(D) An increased risk of congenital malformations has been suggested by several old studies with the use of minor tranquilizers such as diazepam, meprobamate, and chlordiazepoxide during the first trimester of pregnancy. The cause-and-effect relationship has not been proven; in fact, several newer studies failed to show an association between minor tranquilizers and congenital malformations. Nevertheless, the United States Food and Drug Administration recommends that diazepam (caution with midazolam) should not be used in the first trimester of pregnancy.
A 75-year-old patient is undergoing craniotomy for resection of a large astrocytoma. During administration of isoflurane anesthesia, arterial blood gas sampling reveals a Pacó of 30 mm Hg. At this time, this patient's global cerebral blood flow would be approximately A. 10 mL X 100 g brain weight-I X min-I B. 20 mL X 100 g brain weighrl X min-1 C. 30 mL X 100 g brain weighr1 X min-1 D. 40 mL X 100 g brain weighrl X min-1 E. 50 mL X 100 g brain weighr1 X min-I.
(D) Arterial CÓ tension (Pacó) is the single most potent physiologic determinant of cerebral blood flow (CBF) and cerebral blood volume (CBV). Between Pacó values of 20 and 80 mm Hg, CBF decreases 1 to 1.5 mL X 100 g brain weighr1 X min-1 and CBV decreases approximately 0.05 mL X 100 g brain weighr1 for each 1 mm Hg decrease in Pacó• Decreasing the Pacó to 25 to 30 mm Hg should provide near-maximal reductions in CBF, CBV, and ICp, lasting up to 24 hours, without adversely affecting acid-base/electrolyte (e.g., decreases in potassium or ionized calcium) status or decreasing cerebral oxygen delivery (Le., as a result of intense cerebral vasoconstriction and a leftward shift of the oxyhemoglobin dissociation curve). Because this patient's Pacó is 10 mm Hg below normal, CBF also would be reduced to approximately 35 to 40 mL X 100 g brain weighr1 X min.
What discontinuation issues may result for patients who take angiotensin converting enzyme (ACE) inhibitors? (A) Potential clotting abnormalities (B) Cholinergic symptoms (C) Psychosis and agitation (D) Atrial fibrillation
(D) Atrial fibrillation Discontinuing preoperative medications may result in potential clotting abnormalities with non-steroidal anti-in ammatories or antiplatelet drugs; cholinergic symptoms with tricyclic antidepressants; psychosis or agitation with selective serotonin reuptake inhibitors (SSRIs); and rebound hypertension and/or atrial fibrillation with ACE inhibitors. Ref: Butterworth, J.F., Mackey, D.C., & Wasnick, J.D. (2013). Ch 18 & 27 Morgan & Mikhail's Clinical Anesthesiology (5th ed.). New York, NY: Lange Medical Books McGraw-Hill.
The predominant component of Baralyme granules is A. Water B. Silica C. Barium hydroxide D. Calcium hydroxide E. Potassium hydroxide
(D) Baralyme granules are composed primarily of barium hydroxide (20%) and calcium hydroxide (80%). Unlike soda lime, Baralyme granules are inherently hard; thus, the addition of silica to the granules is not necessary. Furthermore, Baralyme granules contajn water in the form of barium hydroxide octahydrate salt and, therefore, can be used more efficiently in dry climates.
Which of the following local anesthetics would produce the lowest concentration in the fetus relative to the maternal serum concentration during a continuous lumbar epidural? A. Etidocaine B. Bupivacaine C. Lidocaine D. Chloroprocaine E. Mepivacaine
(D) Because of the rapid hydrolysis of ester local anesthetics, very little drug is available to cross the placenta. Plasma cholinesterase activity can be reduced up to 40% in pregnant patients, yet the elimination half-life of chloroprocaine is little affected (ranging from 1.5 to 6 minutes).
Select the FALSE statement regarding spinal anatomy and spinal anesthesia. A. The addition of phenylephrine to lidocaine will prolong spinal anesthesia B. A high thoracic sensory block will result in total sympathetic blockade C. The largest vertebral interspace is L5-S 1 D. The dural sac extends to the S3-4 interspace E. Tetracaine provides longer anesthesia than does procaine.
(D) Both phenylephrine and epinephrine will prolong a spinal anesthetic when administering lidocaine. The Taylor approach for spinal anesthesia uses a paramedian approach to the L5-S 1 interspace-the largest interspace of the vertebral column. The sympathetic nervous system originates in the thoracic and lumbar spinal cord TI-L3; therefore, a high thoracic sensory level can cause a complete sympathetic block. The dural sac extends to S2-S3, not S3-S4. The spinal cord extends to L3 in the infant and LI-L2 in adults.
A 24-year-old carpenter is treated for a closed head injury sustained 3 days earlier after falling from a roof. He has been hemodynamically stable, but despite aggressive efforts to pharmacologically reduce ICP, he is now unconscious and unresponsive to painful stimuli. All of the following are clinical criteria consistent with a diagnosis of brain death in this patient EXCEPT A. Persistent apnea for 10 minutes B. Absence of pupillary light reflex C. Persistent spinal reflexes D. Decorticate posturing E. Absence of oropharyngeal reflex
(D) Brain death is defined as irreversible cessation of brain function. It is extremely important to identify and reverse any factors that can mimic the clinical or laboratory criteria for brain death, such as hypothermia, drug intoxication (hypnotic sedatives and major tranquilizers), or metabolic encephalopathy. Clinical criteria for brain death can be divided into those that are related to cortical function and those that are related to brainstem function. Absence of cortical function is manifested by lack of spontaneous motor activity, consciousness, and purposeful movement in response to painful stimuli. Absence of brainstem function is manifested by the inability to elicit reflexes, such as the pupillary response to light and the corneal oculocephalic, oculovestibular, oropharyngeal, and respiratory reflexes. For example, in patients without brainstem function there is no increase in heart rate when atropine is administered intravenously, and there is no respiratory effort during apnea even when the Paco, is greater than 60 mm Hg. Decerebrate and decorticate posturing are not consistent with the diagnosis of brain death.
What is the most common level of approach to perform a stellate ganglion block? (A) C3 (B) C4 (C) C5 (D) C6
(D) C6 An anterior approach is made toward Chassaignac's tubercle, which is the transverse process of C6.
The lower and upper limits of CBP autoregulation (mean arterial blood pressure) are, respectively, A. 25 and 125 mm Hg B. 25 and 200 mm Hg C. 40 and 250 mm Hg D. 50 and 150 mm Hg E. 50 and 200 mm Hg
(D) CBF autoregulation is the intrinsic capability of the cerebral vasculature to adjust its resistance to maintain CBF constant over a wide range of mean arterial blood pressures. In normal subjects the lower limit of CBF autoregulation corresponds to a mean arterial pressure of approximately 50 to 60 mm Hg and the upper limit is a mean arterial pressure of 150 to 160 mm Hg. At mean arterial blood pressures above or below the limits of CBF autoregulation, CBF is pressure dependent. Although the precise mechanism of CBF autoregulation is not known, it is thought to result from an intrinsic characteristic of cerebral vascular smooth muscle that has not yet been identified.
Which of the following substances under normal circumstances exists at the same concentration in both the CSF and blood? A. Potassium B. Chloride C. Glucose D. Sodium E. Albumin
(D) CSF is a clear aqueous solution that is fonned at a rate of 0.35 to 0.40 mL/min or approximately 560 mL/day in the average size human. The turnover time for the total CSF volume is approximately 5 to 7 hours, or a turnover rate of about four times per day. CSF is produced primarily by the choroid plexus, by oxidation of glucose, and by ultrafiltration by cerebral capillaries. The composition of CSF is markedly different from that of plasma. Only sodium exists in both the CSF and plasma at approximately the same concentration. Macromolecules, such as albumin, globulin, and fibrinogen, are almost completely excluded from the CSF. Compared with plasma, CSF contains higher concentrations of chloride and magnesium and lower concentrations of glucose, potassium, bicarbonate, calcium, and phosphate.
If the anesthesia machine is discovered Monday morning having run with 5 L/min of oxygen all weekend long, the most reasonable course of action to take before administering the next anesthetic would be A. Turn machine off for 30 minutes before induction B. Place humidifier in line with the expiratory limb C. Avoid use of sevofturane D. Change the CÓ absorbent E. Administer 100% oxygen for the first hour of the next case.
(D) Clinically significant concentrations of carbon monoxide can result from the interaction of desiccated absorbent, both soda lime and Baralyme. The resulting carboxyhemoglobin level can be as high as 30%. Many of the reported occurrences of carbon monoxide poisoning have been observed on Monday mornings. This is thought to be the case because the absorbent granules are the driest after disuse for 2 days, particularly if the oxygen flow has not been turned off completely. There are several factors that appear to predispose to the production of carbon monoxide: (1) degree of absorbent dryness (completely desiccated granules produce more carbon monoxide than hydrated granules); (2) use of Baralyme versus soda lime (provided that the water content is the same in both); (3) high concentrations of volatile anesthetic (more carbon monoxide is generated at higher volatile concentrations); (4) high temperatures (more carbon monoxide is generated at higher temperatures); and (5) type of volatile used.
Which classication of breathing circuits has complete rebreathing? (A) Open (B) Semi-open (C) Semi-closed (D) Closed
(D) Closed Open and semi-open have no rebreathing; semi-closed has partial rebreathing.
Which of the following is not a physiologic response to pain? (A) Increased peripheral vascular resistance (B) Decreased tidal volume (C) Increased platelet aggregation (D) Decreased urinary sphincter tone
(D) Decreased urinary sphincter tone Pain results in increased urinary sphincter tone.
How does obesity affect the functional residual capacity (FRC) during general anesthesia? (A) Increases FRC 50% (B) Decreases FRC 20% (C) Increases FRC 20% (D) Decreases FRC 50%
(D) Decreases FRC 50% A 20% decrease in FRC exists for nonobese patients. For obese patients undergoing general anesthesia, FRC decreases 50%.
Which corticosteroid has the most potent glucocorticoid activity? (A) Hydrocortisone (B) Prednisone (C) Methylprednisolone (D) Dexamethasone
(D) Dexamethasone The relative glucocorticoid potency of dexamethasone is roughly 25 times that of hydrocortisone.
Interruption of pain impulses can be accomplished through the administration of intrathecal opioids. These opioids act by binding to which of the following sites? (A) Periaqueductal gray (B) Dorsal root ganglia (C) Anterior horn (D) Dorsal horn
(D) Dorsal horn Small quantities of opioids injected within the intrathecal or epidural space produce analgesia segmentally, confined to the sensory nerves entering the dorsal horn of the spinal cord in the vicinity of the area of injection. Presynaptic opioid receptors inhibit primary afferent release of substance P and other neurotransmitters. Postsynaptic opioid receptors decrease spinothalamic tract activity in the dorsal horn.
What actor least affects the spread of spinal local anesthetic? (A) Baricity (B) Drug dosage (C) Site of injection (D) Drug volume
(D) Drug volume While each of the factors affects the spread of local anesthetic in the CSF, drug volume least affects the spread. Other factors influencing the spread of spinal local anesthetic include age, curvature of the spine, intraabdominal pressure, needle direction, patient height, and pregnancy.
Which symptom is not present in advanced aortic stenosis? (A) Angina (B) Dyspnea on exertion (C) Orthostatic syncope (D) Dyspnea at rest
(D) Dyspnea at rest Angina, dyspnea on exertion, and orthostatic and/or exertional syncope are the classic triad o aortic stenosis symptoms
What classic triad of symptoms is associated with aortic stenosis with a valve area <1 cm2? (A) Hypotension, dyspnea on exertion, and pulmonary congestion. (B) Hoarseness, chest pain, and pulmonary emboli. (C) Chest pains, arrhythmias, and embolic events. (D) Dyspnea on exertion, angina, and exertional syncope.
(D) Dyspnea on exertion, angina, and exertional syncope. Rationale: Patients with advanced aortic stenosis have a classic triad o symptoms: dyspnea on exertion (usually associated with congestive heart ailure), angina, and exertional syncope. A is associated with mitral regurgitation. B is associated with mitral stenosis. C is associated with mitral valve prolapse
How does the elimination half-time o remifentanil differ from alfentanil? (A) Elimination half-time is longer or remi entanil. (B) Elimination half-time is shorter or alfentanil. (C) Elimination half-time is similar or alfentanil and remifentanil. (D) Elimination half-time is shorter or remifentanil.
(D) Elimination half-time is shorter or remifentanil. Ester hydrolysis results in shorter elimination half-life or remifentanil as compared to all other opioids.
If the diameter of an intravenous catheter is doubled, flow through the catheter will: A. Decrease by a factor of 2 B. Decrease by a factor of 4 C. Increase by a factor of 8 D. Increase by a factor of 16 E. Increase by a factor of 32
(D) Factors that influence the rate of laminar flow of a substance through a tube is described by the Hagen-Poiseuille law of friction. The mathematical expression of the Hagen-Poiseuille law of friction is as follows. Where V is the flow of the substance, r is the radius of the tube, AP is the pressure gradient down the tube, L is the length of the tube, and Jl is the viscosity of the substance. Note that the rate of laminar flow is proportional to the radius of the tube to the fourth power. If the diameter of an intravenous catheter is doubled, flow would increase by a factor of 2 raised to the fourth power
One goal during a general anesthetic is decrease the neuroendocrine stress response to surgical stimulation. Which medication will be helpful? (A) Vecuronium (B) Midazolam (C) Lidocaine (D) Fentanyl
(D) Fentanyl Narcotics in large doses help decrease release o catecholamines, cortisol, and antidiuretichormone. Muscle relaxants, benzodiazepines, and local anesthetics do not produce similar effects.
Which anticholinergic is classifed as a quaternary amine? (A) Scopolamine (B) Atropine (C) Neostigmine (D) Glycopyrrolate
(D) Glycopyrrolate Atropine and scopolamine are classi ed as tertiary amines. Neostigmine contains a quaternary ammonium.
A patient with dysmenorrhea is scheduled for dilation and curettage (D & C). What preoperative testing is required? (A) CBC (B) Electrolyte panel (C) Chest X-ray (D) HCG
(D) HCG A pregnancy test is needed prior to D & C.
The most important buffering system in the body is: A. Hemoglobin B. Plasma proteins C. Bone D. HC03 E. Phosphate
(D) HCǑ Buffer systems represent the first line of defense against adverse changes in pH. The HC03 - buffer system is the most important system and represents greater than 50% of the total buffering capacity of the body. Other important buffer systems include hemoglobin, which is responsible for approximately 35% of the buffering capacity of blood, phosphates, plasma proteins, and bone.
Which risk factor contributes to myocardial ischemia in a patient with aortic regurgitation? (A) Heart rate 40-50 beats/minute. (B) Heart rate 50-70 beats /minute. (C) Heart rate 80-100 beats/minute. (D) Heart rate 110-120 beats/minute.
(D) Heart rate 110-120 beats/minute. One anesthetic goal of managing a patient with aortic regurgitation is to maintain the heart rate toward the upper limits of normal (i.e., c. 80 to 100 beats/minute). A heart rate that is too slow or an increase in systemic vascular resistance will increase the regurgitant volume (A and B). tachycardia, on the other hand, will contribute to myocardial ischemia in a patient with aortic regurgitation.
The likelihood of a clinically significant hemolytic transfusion reaction resulting from administration of type-specific blood is less than A. 1 in 10 B. 1 in 250 C. 1 in 500 D. 1 in 1000 E. 1 in 10,000
(D) Hemolytic transfusion reactions are often the result of clerical error. There are three main blood compatibility tests that can be performed to reduce the chance of a hemolytic reaction: ABO Rh typing, antibody screening, and crossmatching. With correct ABO and Rh typing the possibility of an incompatible transfusion is less than 1 per 1000. If you add a type and screen, the possibility of an incompatible transfusion is less than 1 per 10,000. Optimal safety occurs when crossmatching is performed.
A patient receives large volumes o 0.9% normal saline during a case. What is the risk associated with this? (A) Hypochloremic alkalosis (B) Hyperchloremic alkalosis (C) Hypochloremic acidosis (D) Hyperchloremic acidosis
(D) Hyperchloremic acidosis When large volumes o normal saline are given, a dilutional hyperchloremic metabolic acidosis with normal anion gap is produced due to the high sodium and chloride content. As serum chloride concentration increases, plasma bicarbonate concentration decreases.
A 54-year-old female is undergoing a total thyroidectomy under general anesthesia. The patient is awakened in the OR, the mouth and pharynx are suctioned, and after intact laryngeal reflexes are demonstrated, the endotracheal tube is removed. Two days later the anesthesiologist is consulted because the patient has severe stridor and upper airway obstruction. The most likely cause of airway obstruction in this patient is A. Damage to the recurrent laryngeal nerve B. Damage to the superior laryngeal nerve C. Tracheomalacia D. Hypocalcemia E. Hematoma
(D) Hypocalcemia The symptoms of hypocalcemia, which may be manifested as laryngospasm or laryngeal stridor, usually develop within the first 24 to 48 hours after total thyroidectomy. After the airway is established and secured, the patient should be treated with IV calcium in the form of either calcium gluconate or calcium chloride
Which laminae receive input from C fibers? (A) III, IV, VI (B) I, VI, X (C) II, VII, IX (D) I, II, V
(D) I, II, V Signals from C bers travel to laminae I, II, V.
An incompetent ventilator pressure-relief valve can result in A. Hypoxia B. Barotrauma C. A low-circuit-pressure signal D. Hypoventilation E. Hyperventilation
(D) If the ventilator pressure-relief valve were to become incompetent, there would be a direct communication between the patient breathing circuit and the scavenging system circuit. This would result in delivery of part of the VT during the inspiratory phase of the ventilator cycle directly to the scavenging system reservoir bag. Therefore, adequate positive-pressure ventilation may not be achieved and hypoventilation of the patient's lungs may result.
A patient with a prosthetic aortic valve who is chronically anticoagulated with Coumadin is scheduled for a radical retropubic prostatectomy. What is the most appropriate management of this patient's anticoagulation? A. Continue Coumadin and replace blood loss intraoperatively with whole blood B. Continue Coumadin and give 2 units of fresh frozen plasma before surgery C. Stop Coumadin on the evening before surgery and administer vitamin K 4 hours prior to surgery D. Stop Coumadin 3 days before surgery and resume Coumadin 1 to 7 days after surgery E. Change to heparin SQ 1 week before surgery and continue the heparin until 6 hours prior to surgery.
(D) In patients with prosthetic heart valves, Coumadin therapy should be discontinued in sufficient time to allow the PT to return to within 20% of normal. This usually requires 1 to 3 days. Coumadin should then be resumed 1 to 7 days after surgery. In this elective case, answer D is the simplest and best choice. If more urgent surgery is needed, intravenous vitamin K (which needs at least 4 hours) or fresh frozen plasma (more rapid effects) will correct the PT. Monitoring the PT will be helpful in ascertaining the appropriate time for surgery from the coagulation standpoint. Heparin usually is not needed .
A patient is admitted to the Post Anesthesia Care Unit with shallow, rapid respirations, diaphoresis, and tachycardia. What is the most likely cause? (A) Delayed awakening (B) Hypothermia (C) Emergence delirium (D) Inadequate oxygenation
(D) Inadequate oxygenation Common causes of delayed awakening reflect metabolic, neurological, and prolonged action of anesthetic drugs. The patient's presentation is not consistent with delayed awakening. Signs and symptoms of hypothermia reflect depressed metabolism, central nervous system depression, bradyarrhythmias, and ventricular arrhythmias. Emergence delirium refers to patients with dysfunctional cognitive signs including agitation, restlessness, ear, lack of orientation, and similar symptoms.
Which of the following would hasten the onset and increase the clinical duration of action of a local anesthetic, and provide the greatest depth of motor and sensory blockade when used for epidural anesthesia? A. Addition to 1 :200,000 epinephrine B. Increasing the volume of local anesthetic C. Increasing the concentration of local anesthetic D. Increasing the dose E. Placing the patient in the head-down position
(D) Increasing the total dose (mass) of local anesthetic is more efficacious in hastening the onset and increasing the duration of an epidural anesthetic than increasing the volume or increasing the concentration (while holding the total dose constant).
What results when alpha-1 receptors are activated? (A) Presynaptic nerve terminals are stimulated. (B) Adenylate cyclase activity is inhibited. (C) Negative eedback loop inhibits norepinephrine release. (D) Intracellular calcium ion concentration increases.
(D) Intracellular calcium ion concentration increases. Alpha-1 receptors activate postsynaptic adrenoceptors resulting in increased intracellular calcium. Alpha-2 receptors are located presynaptically. Adenylate cyclase activity is inhibited when alpha-2 receptors are activated. When stimulating alpha-2 receptors, calcium ion concentration decreases creating a negative eedback loop that inhibits norepinephrine release.
1. What results when alpha-1 receptors are activated? (A) Presynaptic nerve terminals are stimulated. (B) Adenylate cyclase activity is inhibited. (C) Negative eedback loop inhibits norepinephrine release. (D) Intracellular calcium ion concentration increases.
(D) Intracellular calcium ion concentration increases. Alpha-1 receptors activate postsynaptic adrenoceptors resulting in increased intracellular calcium. Alpha-2 receptors are located presynaptically. Adenylate cyclase activity is inhibited when alpha-2 receptors are activated. When stimulating alpha-2 receptors, calcium ion concentration decreases creating a negative eedback loop that inhibits norepinephrine release
True statements regarding inclusion of intrathecal morphine, fentanyl, or sufentanil in obstetric anesthesia practice include each of the following EXCEPT: A. The chief site of action is the substantia gelatinosa of the dorsal horn of the spinal column B. There is no motor blockade C. There is no sympathetic blockade D. Pain relief is adequate for the second stage of labor E. Lipophilic narcotics are associated with less respiratory depression than nonlipophilic narcotics.
(D) Intrathecal opiates (e.g., morphine, fentanyl, sufentanil) are very effective in relieving the visceral pain during the first stage of labor. Intrathecal opiates, except for meperidine, which has local anesthetic properties, do not provide adequate pain relief for the second stage somatic pain.
Which of the following may cause prolonged sedation? Select (2) two (A) Echinacea (B) Ephedra (C) Garlic (D) Kava-kava (E) Valerian
(D) Kava-kava (E) Valerian Anesthetic implications for patients taking echinacea include allergic reactions, liver enzyme induction, and immune system dysfunction. The sympathomimetic effects of ephedra predispose to myocardial infarction and stroke. Garlic increases the possibility of bleeding.
Which of the following medications block alpha- and beta receptors? (A) Phentolamine (B) Isoproterenol (C) Propranolol (D) Labetalol
(D) Labetalol Alphā, betā, and betá receptors are blocked by labetalol. A competitive block is produced by phentolamine (alphā and alphá receptors). Isoproterenol is a selective beta blocker whereas propranolol is a nonselective betā and betá receptor blocker.
Clinically significant methemoglobinemia may result from administration of large doses of A. Chloroprocaine B. Bupivacaine C. Etidocaine D. Prilocaine E. Lidocaine
(D) Large doses of prilocaine, usually greater than 600 mg epidurally, can result in clinically significant methemoglobinemia. Prilocaine is metabolized by the liver to o-toluidine, which is responsible for the oxidation of hemoglobin to methemoglobin. Methemoglobinemia can be treated with IV methylene blue, or it will resolve spontaneously.
What local anesthetic is linked to cauda equina syndrome? (A) Ropivacaine (B) Bupivacaine (C) Tetracaine (D) Lidocaine
(D) Lidocaine Administration of spinal lidocaine and epidural 2-chloroprocaine (inadvertent dural puncture) has been implicated in cauda equina syndrome as well as transient neurological symptoms
Differences in which of the following local anesthetic properties accounts for the fact that the onset of an epidural block with 3% 2-chloroprocaine is more rapid than 2% lidocaine? A. Protein binding B. pKa C. Lipid solubility D. Concentration E. Ester versus amide structure
(D) Local anesthetics are weak bases. The neutral (nonionized) form of the molecule is able to pass through the lipid nerve cell membrane, whereas the ionized (protonated) form actually produces anesthesia. Chloroprocaine has the highest pKa of local anesthetics, meaning that a greater percentage of it will exist in the ionized form at any given pH than any of the other local anesthetics. Despite this fact, 3% chloroprocaine has a more rapid onset than 2% lidocaine, presumably because of the greater number of molecules (concentration). If one compares onset time for 1.5% lidocaine against 1.5% chloroprocaine, the former will have a more rapid onset.
Toxic side effects of MgS04 when used to treat preeclampsia include all the following EXCEPT A. Cardiac arrest B. Neonatal hypotonia C. Potentiation of neuromuscular blockade with vecuronium. D. Renal failure E. Hypoventilation.
(D) Magnesium sulfate overdose can lead to both maternal and neonatal complications, which include muscle weakness, respiratory depression, and cardiac failure. If renal failure occurs (as a result of severe preeclampsia and not as a result of MgSO 4)' plasma magnesium concentrations should be monitored closely because MgS04 is excreted by the kidneys. The therapeutic range for plasma magnesium concentrations is 4 to 8 mEq/L. Plasma magnesium concentrations of 10 mEq/L can result in loss of deep tendon reflexes, and concentrations of 15 mEq/L can result in sinoatrial and atrioventricular block and respiratory paralysis. Should plasma magnesium concentrations increase to greater than 25 mEq/L, cardiovascular collapse and cardiac arrest may ensue.
What variables are needed to calculate systemic vascular resistance (SVR)? (A) Body surface area, cardiac output, and central venous pressure (B) Mean arterial pressure, heart rate, and pulmonary capillary wedge pressure (C) Mean arterial pressure, cardiac output, and pulmonary capillary wedge pressure (D) Mean arterial pressure, cardiac output, and central venous pressure
(D) Mean arterial pressure, cardiac output, and central venous pressure Rationale: SVR = 80 x [MAP-CVP]/CO.
What does the American Society of Anesthesiologists' Closed Claims Project database identify as the most common single source of injury pertaining to the anesthesia gas machine? (A) Failure of the anesthesia delivery equipment (B) Faulty ventilator (C) Inaccurate calibration of the oxygen analyzer (D) Misconnect or disconnect of breathing circuit components
(D) Misconnect or disconnect of breathing circuit components The breathing circuit was the most common single source o injury (39%). Nearly all damaging events were related to misconnect or disconnect. A misconnect was deined as a non functional and unconventional configuration of breathing circuit components or attachments.
Which agent increases the cerebral metabolic rate for oxygen (CMRÓ)? (A) Halothane (B) Isoflurane (C) Sevoflurane (D) Nitrous oxide
(D) Nitrous oxide Cerebral vasodilatation and increased cerebral blood ow are linked to nitrous oxide administration without volatile anesthetics. Iso urane, sevo urane, des urane, and halothane decrease CMRO 2.
Which route of administration of fentanyl is subject to the hepatic first-pass effect? (A) Transdermal patch (B) Intravenous injection (C) Sublingual spray (D) Oral tablet
(D) Oral tablet Gastrointestinal absorption is subject to hepatic first-pass effect.
Which is an indication for a celiac plexus block? (A) Post-traumatic hypoperfusion of the arm (B) Lower extremity vascular insufficiency (C) Intractable lumbar pain (D) Pain resulting from pancreatic malignancy
(D) Pain resulting from pancreatic malignancy Pain associated with an intra-abdominal malignancy is a primary indication for this intervention.
Which peripheral nerve block provides complete anesthesia or ankle surgery? (A) Femoral (B) Sciatic (C) Obturator (D) Popliteal
(D) Popliteal The femoral block is useful for analgesia but not total anesthesia for ankle procedures. For surgical procedures below the knee, the popliteal approach to sciatic nerve block provides complete anesthesia. Surgery above and below the knee and including the knee are anesthetized using other approaches to the sciatic nerve block. The obturator block is useful for knee procedures
Twenty- four hours following an epidural anesthetic the patient complains of occipital headache, nausea, vomiting, and double vision. What is the most likely cause? (A) Neurologic injury (B) Spinal hematoma (C) Epidural hematoma (D) Postdural puncture headache
(D) Postdural puncture headache Signs and symptoms are consistent with a postdural puncture headache. Specifcally, a headache associated with changes in position (i.e., sitting or standing worsens the pain). Sharp back and leg pain with accompanying motor weakness are symptoms of spinal or epidural hematoma.
What statement is false regarding the lateral decubitus position? (A) Rhabdomyolysis may occur. (B) Flex the dependent arm <90 degrees. (C) Pad the lateral aspect of the dependent leg. (D) Pulmonary blood flow to the dependent lung decreases.
(D) Pulmonary blood flow to the dependent lung decreases. In the lateral decubitus position, blood ow to the dependent lung is increased.
For which heart rhythm is cardioversion not indicated? (A) Atrial flutter (B) Atrial fibrillation (C) Stable ventricular tachycardia (D) Pulseless ventricular tachycardia
(D) Pulseless ventricular tachycardia Unstable ventricular tachycardia requires defibrillation
Cardiac tamponade is associated with A. Pulsus altemans B. Pulsus tardus C. Pulsus parvus D. Pulsus paradoxus E. Bisferiens pulse
(D) Pulsus paradoxus describes an inspiratory fall in systolic arterial blood pressure of greater than 10 mm Hg often seen in cardiac tamponade. This inspiratory decline in systolic blood pressure represents an exaggeration of the normal small drop in blood pressure seen with inspiration in spontaneously breathing patients. In cardiac tamponade, ventricular filling is limited by the presence of blood, thrombus, or other material in the pericardial space. During inspiration in the spontaneously breathing patient, negative intrathoracic pressure enhances filling of the right ventricle. Because total cardiac volume is limited by the pressurized pericardium in tamponade cases, as the right ventricle fills with inspiration, left ventricular preload and blood pressure decline. Pulsus paradoxus is occasionally seen in cases of severe airway obstruction and right ventricular infarction. Pulsus parvus and pulsus tardus describe, respectively, the diminished pulse wave and delayed upstroke in patients with aortic stenosis. Pulsus altemans describes alternating smaller and larger pulse waves, a condition sometimes seen in patients with severe left ventricular dysfunction. A bisferiens pulse is a pulse waveform with two systolic peaks seen in cases of significant aortic valvular regurgitation
All of the following characterize packed RBCs that have been stored for 35 days at 4°C in citrate phosphate dextrose adenine- I (i.e., CPDA-I) anticoagulant preservative EXCEPT A. Serum potassium greater than 70 mEq/ L B. pH less than 7.0 C. Blood glucose less than 100 mg/dL D. P50 of 28 E. 2,3-diphosphoglycerate (2,3-DPG) less than I ug/mL
(D) RBCs are cooled to about 4°C to decrease cellular metabolism. CPDA-l is a preservative anticoagulant solution often added to blood. It contains citrate, phosphate, dextrose, and adenine. The citrate is used to bind calcium and acts as an anticoagulant. Phosphate acts as a buffer. Dextrose is added, as an energy source for cellular metabolism, the day of donation to raise the blood sugar to greater than 400 mg/dL. At 35 days, the glucose level drops below 100 mg/dL. Adenine is added as a substrate source so that the cells can produce adenosine triphosphate (ATP). Other biochemical changes include a fall in pH to about 6.7 and a rise in plasma potassium from around 4 mEq/L on the day of donation to 76 mEq/L at 35 days. Concentrations of 2,3-DPG fall below 1 IlMlmL, which causes a leftward shift in the oxyhemoglobin dissociation curve that allows for an increased oxygen affinity for the hemoglobin. This leftward shift produces a Pso value less than the normal 26 mm.
An increase in Pacó2 of 10 mm Hg will result in a decrease in pH of A. 0.01 pH units B. 0.02 pH units C. 0.04 pH units D. 0.08 pH units E. None of the above
(D) Respiratory acidosis is present when the Pacó exceeds 44 mm Hg. Respiratory acidosis is caused by decreased elimination of CÓ by the lungs (Le., hypoventilation) or increased metabolic production of CÓ, An acute increase in Pacó of 10 mm Hg will result in a decrease in pH of approximately 0.08 pH units. The acidosis of arterial blood will stimulate ventilation via the carotid bodies and the acidosis of cerebrospinal fluid will stimulate ventilation via the medullary chemoreceptors located in the fourth cerebral ventricle. Volatile anesthetics greatly attenuate the carotid body-mediated and aortic body-mediated ventilatory responses to arterial acidosis, but they have little effect on the medullary chemoreceptor-mediated ventilatory response to cerebrospinal fluid acidosis.
A 44-year-old patient is hyperventilated to a Pacó of 24 mm Hg for 48 hours. What [HC03-] would you expect (normal [HC03-] is 24 mEq/L)? A. 10 mEq/L B. 12 mEq/L C. 14 mEq/L D. 16 mEq/L E. 18 mEq/L
(D) Respiratory alkalosis is present when the Pacó is less than 36 mm Hg. There are three compensatory mechanisms responsible for attenuating the increase in pH that accompanies respiratory alkalosis. First, there is an immediate shift in the equilibrium of the HC03 - buffer system, which results in the production of CÓ, Second, alkalosis stimulates the activity of phosphofructokinase, which increases glycolysis and the production of pyruvate and lactic acid. Third, there is a decrease in reabsorption of HC03 - by the proximal and distal renal tubules. These three compensatory mechanisms result in a maximum decrease in [HC03 -] of approximately 5 mEq/L for every 10 mm Hg decrease in Pacó less than 40 mm Hg.
Although ~-adrenergic receptor blockade is the best treatment for reentrant tachydysrhythmia associated with Romano-Ward syndrome, these dysrhythmias can also be effectively treated with A. Lidocaine B. Procainamide C. Quinidine D. Left stellate ganglion blockade E. Right stellate ganglion blockade
(D) Romano-Ward syndrome is a rare congenital abnormality characterized by prolonged QT intervals on the ECG. Jervell-Lange-Nielsen syndrome is a congenital syndrome characterized by prolonged QT intervals on the ECG in association with congenital deafness. An imbalance between the right and left sides of the sympathetic nervous system may play a role in the etiology of these syndromes. This imbalance can be temporarily abolished with a left stellate ganglion block, which shortens the QT intervals. If this is successful, surgical ganglionectomy may be performed as permanent treatment (
Which nerve provides sensation to the anteromedial foot and medial lower leg? (A) Deep peroneal (B) Sural (C) Superficial peroneal (D) Saphenous
(D) Saphenous The deep peroneal nerve provides sensation to webbing between the first and second digits. The superficial personal nerve supplies sensation to the dorsum of the foot and toes. The sural nerve provides sensation to the lateral foot.
What AANA Standard guides the practice of providing post-anesthesia report? (A) Standard I (B) Standard III (C) Standard V (D) Standard VII
(D) Standard VII Standard VII speaks to the need to "transfer responsibility" for continuity of care.
What factor is not associated with postoperative pulmonary complications? (A) ASA III (B) Cigarette smoking (C) Aortic aneurysm repair (D) Surgery lasting 3 hours
(D) Surgery lasting 3 hours Factors that lead to postoperative pulmonary complications include each of the items except surgery lasting 3 hours. Surgery lasting 4 or more hours is linked to postoperative pulmonary complications.
Prior to general anesthesia the patient reports taking daily imipramine. What is your most serious concern or this patient? (A) Dry mouth (B) Sedation (C) Orthostatic hypotension (D) Sympathomimetic activity
(D) Sympathomimetic activity Dry mouth, sedation, orthostatic hypotension, prolonged QT interval, dry mouth, blurred vision, and urinary retention are side e ects linked to tricyclic antidepressants- CAs (imipramine). The most serious concern or patients taking CAs is sympathomimetic activity resulting in hypertensive crisis and cardiac arrhythmias.
Which principle is not included in radiation safety? (A) Time (B) Distance (C) Shielding (D) Temperature
(D) Temperature Rationale: Time, distance, and shielding guide the need or anesthesia providers to avoid the hazards o radiation in the operating room. No relationship exists between the operating room temperature and radiation safety.
A 56-year-old male patient is anesthetized for elective coronary revascularization. A urinary catheter is placed after induction and coupled to a temperature transducer. A pulmonary artery catheter is inserted, and the temperature probe on the distal portion of the catheter is also connected to a transducer. The reason for measuring the temperature of both the bladder and the blood in the pulmonary vasculature is A. Both are necessary for determining cardiac output by the thermodilution technique B. Bladder temperature is more accurate prebypass; pulmonary artery catheter temperature is more accurate postbypass C. Pulmonary artery catheter temperature is more accurate prebypass; bladder temperature is more accurate postbypass D. It is helpful in determining the likelihood of recooling after discontinuation of cardiopulmonary bypass E. It is the average of these two temperatures, which is important in determining patient body warmth
(D) Temperature of the thermal compartment can be measured accurately in the pulmonary artery, distal esophagus, tympanic membrane, or nasopharynx. These temperature monitoring sites are reliable, even during rapid thermal perturbations such as cardiopulmonary bypass. Other temperature sites, such as oral, axillary, rectal, and urinary bladder, will estimate core temperature reasonably accurately except during extreme thermal perturbations. During cardiac surgery, the temperature of the urinary bladder is usually equal to the pulmonary artery when urine flow is high. However, it may be difficult to interpret urinary bladder temperature because it is strongly influenced by urine flow. The adequacy of rewarming after coronary artery bypass is thus best evaluated by considering both the core and urinary bladder temperatures
Anastomosis of the right atrium to the pulmonary artery (Fontan procedure) is a useful surgical treatment for each of the following congenital cardiac defects EXCEPT A. Tricuspid atresia B. Hypoplastic left heart syndrome C. Pulmonary valve stenosis D. Truncus arteriosus E. Pulmonary artery atresia
(D) The Fontan procedure (usually modified Fontan) is an anastomosis of the right atrial appendage to the pulmonary artery. This procedure is most frequently performed to treat congenital cardiac defects, which decrease pulmonary artery blood flow (e.g., pulmonary atresia and stenosis, and tricuspid atresia). The Fontan procedure is also used to increase pulmonary blood flow when it is necessary to surgically convert the right ventricle to a systemic ventricle (e.g., hypoplastic left heart syndrome). Truncus arteriosus occurs when a single arterial trunk, which overrides both ventricles (which are connected via a ventricular septal defect), gives rise to both the aorta and pulmonary artery. Surgical treatment of this defect includes banding of the right and left pulmonary arteries and enclosure of the associated ventricular septal defect.
In a malpractice action, the final determination of culpability is determined by the defendant physician's. A. Reputation in the community B. Credentials and education C. Rapport with the patient and family D. Adherence to the standards of practice E. History of previous lawsuits.
(D) The Physician's Insurers Association of America conducted a study in 1992 wherein they analyzed malpractice claims reported by physician-owned insurance companies that were closed between January 1985 and June 199 1. Fewer than 5% o' all reported claims were made against anesthesiologists, and those that resulted in payments to the plaintiff comprised fewer than 1% of the total paid claims against physicians of all specialties. The most common type of claim was that made against anesthesiologists who were participating in the care of patients for pregnancy and childbirth. The final determination of culpability or lack thereof is contingent on determining whether the physician followed standards of practice for his or her specialty.
A VVI pacemaker programmed to pace at a rate of 70 beats/min is noted on the preoperative ECG to pace at 61 beats/min. The most likely reason for this decrease in the pacing heart rate is: A. Decreased atrial rate B. Third-degree heart block C. Trifascicular heart block D. Battery failure E. Normal variation
(D) The anesthetic management of patients with artificial cardiac pacemakers should include ECG monitoring to confirm continued function of the pulse generators as well as emergency equipment (e.g., electrical defibrillator, external converter magnet) and drugs (atropine, isoproterenol) to maintain an acceptable intrinsic heart rate if the artificial pacemaker malfunctions. Inadvertent displacement of the endocardial electrodes by catheters has not been reported when the electrodes have been in place for 4 weeks or more. In general, anesthetic drugs will not alter the function of artificial cardiac pacemakers. However, the stimulation thresholds for ventricular capture are not static values and can be altered by a number of physiologic events. For example, acute hypokalemia and respiratory alkalosis will increase the threshold for ventricular capture, which could result in a loss of pacing. In contrast, acute hyperkalemia and acidosis will decrease the threshold for ventricular capture, which may make the patient vulnerable to ventricular fibrillation. A decrease in the programmed rate of the pacemaker greater than 10% is a sign of battery failure. Should this occur, elective surgery should be canceled and a thorough evaluation of the pacemaker should be undertaken
A mechanical ventilator (e.g., Ohmeda 7000) is set to deliver a tidal volume (VT) of 500 mL at a rate of 10 breaths/min and an inspiratory-to-expiratory (lIE) ratio of 1 :2. The fresh gas flow into the breathing circuit is 6 L/min. In a patient with normal total pulmonary compliance, the actual VT delivered to the patient would be A. 400mL B. 500 mL C. 600mL D. 700mL E. 800 mL
(D) The contribution of the fresh gas flow from the anesthesia machine to the patient's VT should be considered when setting the VT of a mechanical ventilator. Because the ventilator pressure-relief valve is closed during inspiration, both the gas from the ventilator bellows and the fresh gas flow will be delivered to the patient breathing circuit. In this question, the fresh gas flow is 6 Umin or 100 mL/sec (6000 mL/60). Each breath lasts 6 sec (60 secllO breaths) with inspiration lasting 2 sec (lIE ratio = 1 :2). Under these conditions, the VT delivered to the patient by the mechanical ventilator will be augmented by approximately 200 mL. In some ventilators, like the Ohmeda 7900, VT is controlled for the fresh-gas flow rate such that the delivered VT is always the same at the dial setting.
A 72-year-old female with insulin-dependent diabetes mellitus and coronary artery disease is to undergo debridement of an ulcer on her right great toe. An ankle block is planned. Which nerves must be adequately blocked in order to perform the surgery? A. Deep peroneal, posterior tibial, saphenous, sural B. Deep peroneal, saphenous, superficial peroneal, sural C. Deep peroneal, posterior tibial, superficial peroneal, sural D. Deep peroneal, posterior tibial, saphenous, superficial peroneal E. Deep peroneal, posterior tibial, saphenous
(D) The great toe is innervated by the deep peroneal, posterior tibial, superficial peroneal, and occasionally the saphenous nerve. All four of these nerves should be blocked for surgery on the great toe.
The line isolation monitor A. Prevents microshock B. Prevents macroshock C. Provides electrical isolation in the OR D. Sounds an alarm when grounding occurs in the OR E. Provides a safe electrical ground
(D) The line isolation monitor alarms when grounding occurs in the OR or when the maximum current that a short circuit could cause exceeds 2-5 mAo The line isolation monitor is purely a monitor and does interrupt electrical current. Therefore, the line isolation monitor will not prevent microshock or macroshock.
The maximum dose of lidocaine containing I :200,000 epinephrine that can be administered to a 70-kg patient for regional anesthesia is A. 50 mg B. 100 mg C. 200 mg D. 500 mg E. 1000 mg
(D) The maximum dose of local anesthetics containing I :200,000 epinephrine that can be used for major nerve blocks is lidocaine, sao mg; mepivacaine, 500 mg; prilocaine, 600 mg; bupivacaine, 225 mg; etidocaine, 400 mg; and tetracaine, 200 mg
The half-life of albumin in the plasma is A. 6 hours B. 2 days C. 8 days D. 20 days E. 90 days
(D) The normal serum albumin level is 3.5 to 5 gldL. Albumin is synthesized by the liver. Because of the long plasma half-life of about 20 days, low levels of albumin may be a late indicator of chronic hepatic failure. Low levels may also be the result of nephrotic syndrome, poor nutrition, and protein-losing enteropathies
Cardiac output returns to within 10% of nonpregnant values by how long postpartum? A. 1 day B. 2 days C. 1 week D. 2 weeks E. 1 month
(D) The numerous changes that take place in the cardiovascular system during pregnancy provide for the needs of the fetus and prepare the mother for labor and delivery. During the first trimester of pregnancy, cardiac output increases by approximately 30% to 40%. At term, the cardiac output is increased 50% over nonpregnant values. This increase in cardiac output is due to an increase in stroke volume and an increase in heart rate. During labor the cardiac output increases another 10% to 15% during the latent phase, 25% to 30% during the active phase, and 40% to 45% during the expulsive stage. The greatest increase in cardiac output occurs immediately after delivery of the newborn when the cardiac output can increase to greater than 75% to 80% above prelabor values. This final increase in cardiac output is attributed primarily to autotransfusion and increased venous return associated with uterine involution. Cardiac output falls to just below prelabor values 48 hours after delivery. But it takes about 2 weeks time for the cardiac output to decrease to within 10% of prepregnant values. By 12 to 24 weeks postpartum, cardiac output returns to normal nonpregnant values
Which of the following patients is most likely to need an emergency hysterectomy for uncontrolled bleeding at the time of delivery. A. Patient with placenta abruption . B. Patient undergoing a vaginal birth after a cesarean section. C. Patient with quadruplets. D. Patient with a placenta previa (not bleeding) for an elective repeat cesarean section. E. Patient with an abdominal pregnancy.
(D) The patient with placenta previa and a previous scar in the uterus has a very high chance of needing an emergency cesarean hysterectomy for uncontrolled bleeding because of a placenta accreta (abnormally adherent placenta). The incidence of placenta accreta in a patient with placenta previa and no previous cesarean section is 5% to 7%, with one previous cesarean section is about 10% to 30%, and with two or more previous sections is 40% to 70%. About two thirds of patients with placenta accreta require a cesarean hysterectomy.
The primary determinants of myocardial Ó consumption, from most to least important, are: A. Preload > afterload > heart rate B. Heart rate> preload> afterload C. Afterload > preload > heart rate D. Heart rate > afterload > preload E. Afterload > heart rate> preload
(D) The primary goal in the anesthetic management of patients with coronary artery disease is to maintain the balance between myocardial Ó supply and demand. Myocardial Ó consumption (i.e., myocardial Ó demand) is determined by three factors: myocardial wall tension, heart rate, and myocardial contractile state. Myocardial wall tension is directly related to the end-diastolic ventricular pressure or volume (preload) and systemic vascular resistance (afterload). In general, myocardial work in the form of increased heart rate results in the greatest increase in myocardial Ó consumption. Also, for a given increase in myocardial work, the increase in myocardial Ó consumption is much less with volume work (preload) than with pressure work (afterload)
The relationship between intra-alveolar pressure, surface tension, and the radius of an alveolus is described by A. Graham's law B. Beer's law C. Newton's law D. Laplace's law E. Bernoulli's law
(D) The relationship between intra-alveolar pressure, surface tension, and the radius of alveoli is described by Laplace's law for a sphere, which states that the surface tension of the sphere is directly proportional to the radius of the sphere and pressure within the sphere. With regard to pulmonary alveoli , the mathematical expression of Laplace's law is as Follows: T = 1/2PR where T is the surface tension, P is the intra-alveolar pressure, and R is the radius of the alveolus. In pulmonary alveoli, surface tension is produced by a liquid film lining the alveoli.
Of the following statements concerning the safe storage of compressed-gas cylinders, choose the one that is FALSE. A. Should not be handled with oily hands. B. Should not be stored near flammable material. C. Should not be stored in extreme heat or cold. D. Paper or plastic covers should not be removed from the cylinders before storage. E. All of the above statements are true
(D) The safe storage and handling of compressed-gas cylinders is of vital importance. Compressedgas cylinders should not be stored in extremes of heat or cold, and they should be unwrapped when stored or when in use. Flames should not be used to detect the presence of a gas. Oily hands can lead to difficulty in handling of the cylinder, which can result in dropping the cylinder. This can cause damage to or rupture of the cylinder, which can lead to an explosion (Ehrenwerth: Anesthesia Equipment: Principles and Applications, pp 8-11). 23
During a normal VT (500-mL) breath, the transpulmonary pressure increases from 0 to 5 cm H20. The product of transpulmonary pressure and VT is 2500 cm H20-mL. This expression of the pressurevolume relationship during breathing determines what parameter of respiratory mechanics? A. Lung compliance B. Airway resistance C. Pulmonary elastance D. Work of breathing E. Closing capacity
(D) The work of breathing is defined as the product of transpulmonary pressure and VT. The work of breathing is related to two factors: the work required to overcome the elastic forces of the lungs and the work required to overcome airflow or frictional resistances of the airways .
756. Each of the following is a relative contraindication to the sitting position EXCEPT A. Ventriculoatrial shunt B. Platypnea-orthodeoxia. C. Right-to-Ieft intracardiac shunt . D. Ventriculoperitoneal shunt. E. Patent foramen ovale.
(D) There are a number of practical reasons for using the sitting position. These include better surgical exposure; less tissue retraction and bleeding; a lower incidence of cranial nerve damage; ready access to the patient's airway, chest, and extremities; and more complete resection of the lesion. Although there are minimal objective data, there are, nonetheless, some conditions considered relative contraindications to the sitting position. These include an open ventriculoatrial shunt, presence of right-to-Ieft intracardiac shunts (because of the potential for paradoxical VAE), presence of platypnea-orthodeoxia (Le., patients who are well oxygenated in the supine position but become hypoxic when they assume the upright position; these patients have hemodynamic-dependent right-to-Ieft intracardiac shunts), and the tendency to develop cerebral ischemia when the patient assumes the upright position. In contrast to the situation with ventriculoatrial shunts, air cannot be entrained via a ventriculoperitoneal shunt directly into the circulation. Ventriculoperitoneal shunt is not a relative contraindication to surgery in the sitting position.
For which medication is regional anesthesia an absolute contraindication? (A) Clopidogrel (B) Unfractionated heparin (C) Low-molecular-weight heparin (D) Thrombolytics
(D) Thrombolytics Regional anesthesia may be performed safely when the waiting period is adhered to for each of the medications except thrombolytics.
What statement about pressure-controlled ventilation is False? (A) Limited peak inspiratory pressure exists. (B) Inspiratory pressure is controlled. (C) Tidal volume is uncontrolled. (D) Tidal volume is controlled
(D) Tidal volume is controlled T idal volume is controlled with volumecontrolled ventilation rather than pressure-controlled ventilation.
Which is an α2 agonist? (A) Carbamazepine (B) Tapentadol (C) Phenytoin (D) Tizanidin
(D) Tizanidin Tizanidine is an α2 agonist sometimes use ul in spastic pain
The mechanism of the transcutaneous electrical nerve stimulator (TENS) unit in relieving pain is A. Direct electrical inhibition of type A and C fibers B. Depletion of neurotransmitter in nociceptors C. Hyperpolarization of spinothalamic tract neurons D. Activation of inhibitory neurons E. Distortion of nociceptors
(D) Transcutaneous nerve stimulation is low-intensity, mixed-frequency (2 and 100 Hz) electrical stimulation that is thought to produce analgesia by releasing endorphins. This technique is effective in treating nociceptive and deafferentation syndromes by a mechanism that is not reversed by naloxone. The mechanism is thought to be activation of inhibitory neurons andlor release of endogenous opiates
During a general anesthetic you suspect an episode of malignant hyperthermia (MH). What will you do First? (A) Call the MHAUS hotline. (B) Administer dantrolene. (C) Inform the surgeon. (D) Turn off inhalational agents
(D) Turn off inhalational agents When suspicion of an episode of malignant hyperthermia exists, each of the responses is in order; however, turning of the inhalational agents is the first priority.
Which of the following elements in the postoperative note are not required by the Center for Medicare and Medicaid Services (CMS)? (A) Mental status (B) Temperature (C) Pain (D) Urine output
(D) Urine output In addition to A, B, and C, respiratory and cardiovascular parameters, nausea, vomiting, and hydration are required documentation per CMS
A patient with rheumatoid arthritis is undergoing a total knee replacement. What is the recommended glucocorticoid dosing regimen? (A) Usual corticosteroid dose + hydrocortisone 25 mg (B) Usual corticosteroid dose + hydrocortisone 100 mg (C) Usual corticosteroid dose + hydrocortisone 150 mg (D) Usual corticosteroid dose + hydrocortisone 50 mg
(D) Usual corticosteroid dose + hydrocortisone 50 mg. Steroid coverage is based on the degree o surgical stress. Total joint replacements are considered moderate surgical stress. For minor procedures, 25 mg o hydrocortisone is recommended, whereas major stress procedures including cardiac and large vascular procedures require 100-150 mg every 8 hours or 2-3 days.
Which clotting factor is not synthesized in the liver? (A) II (B) IV (C) VII (D) VIII
(D) VIII Most clotting factors are synthesized in the liver except actor VIII, that is, von Willebrand factor, which is synthesized by vascular endothelial cells.
Frost develops on the outside of an N20 compressed-gas cylinder during general anesthesia. This phenomenon indicates that A. The saturated vapor pressure of N20 within the cylinder is rapidly increasing B. The cylinder is almost empty C. There is a rapid transfer of heat to the cylinder D. The flow of N20 from the cylinder into the anesthesia machine is rapid E. None of the above
(D) Vaporization of a liquid requires the transfer of heat from the objects in contact with the liquid (e.g., the metal cylinder and surrounding atmosphere). For this reason, at high gas flows, atmospheric water will condense as frost on the outside of compressed-gas cylinders
1% enfturane, 70% N20, and 30% Ó are administered to a patient for 30 minutes. The expired enfturane concentration measured is 1 %. N 20 is shut off and a mixture of 30% Ó, 70% N2 with 1% enfturane is administered. The expired enfturane concentration measured 10 minutes after the start of this new mixture is 2.3%. The best explanation for this observation is A. Intermittent back pressure (pumping effect.) B. Diffusion hypoxia . C. Concentration effect. D. Effect of N20 solubility in enfturane. E. Effect of similar mass-to-charge ratios of N20 and CÓ.
(D) Vaporizer output can be affected by the composition of the carrier gas used to vaporize the volatile agent in the vaporizing chamber, especially when nitrous oxide is either initiated or discontinued. This observation can be explained by the solubility of nitrous oxide in the volatile agent. When nitrous oxide and oxygen enter the vaporizing chamber, a portion of the nitrous oxide dissolves in the liquid agent. Thus, the vaporizer output transiently decreases. Conversely, when nitrous oxide is withdrawn as part of the carrier gas, the nitrous oxide dissolved in the volatile agent comes out of solution, thereby transiently increases the vaporizer output (Eh ren werth: Anesthesia Equipment: Principles and Applications, pp 68-69).
How soon must Fresh Frozen plasma be transfused once thawed? (A) Within 4 hours (B) Within 8 hours (C) Within 12 hours (D) Within 24 hours
(D) Within 24 hours Once fresh frozen plasma has been thawed, it must be given within 24 hours to avoid wastage. Ref: Butterworth, J.F., Mackey, D.C., & Wasnick, J.D. (2013). Ch 51 Morgan & Mikhail's Clinical Anesthesiology (5th ed.). New York, NY: McGraw-Hill.
Which laboratory test provides the most comprehensive assessment o coagulation in a patient with severe cirrhosis? (A) International normalized ratio (B) Prothrombin time (C) Partial thromboplastin time (D) thromboelastography
(D) thromboelastography Thromboelastography allows assessment o the initial clotting process through fibrinolysis which is more comprehensive than an isolated measure o clotting time.
You plan to use an intravenous regional technique for a hand surgery. What is your greatest concern? (A) Duration of the case (B) Using the dual tourniquet system (C) tourniquet discomfort (D) tourniquet failure
(D) tourniquet failure A large volume of local anesthetic from the periphery to the central circulation represents the most serious concern associated with intravenous regional anesthesia. The other variables pose challenges, but are readily remedied.
How is the brachial plexus formed? (A) Roots, divisions, trunks, cords, branches (B) Divisions, trunks, cords, branches (C) Cords, divisions, roots, branches (D) Trunks, divisions, cords, branches
(D) trunks, divisions, cords, branches Rationale: Nerve roots leaving the intervertebral foramina join to form trunks, divisions, cords, and branches.
Which of the following statements concerning the distribution of alveolar ventilation in the upright lungs is true? A. The distribution of V A is not affected by body posture B. Alveoli at the apex of the lungs (nondependent alveoli) are better ventilated than those at the base C. All areas of the lungs are ventilated equally D. Alveoli at the base of the lungs (dependent alveoli) are better ventilated than those at the apex E. Alveoli at the central regions of the lungs are better ventilated than those at the base or apex
(D)Alveoli at the base of the lungs (dependent alveoli) are better ventilated than those at the apex. The orientation of the lungs relative to gravity has a profound effect on efficiency of pulmonary gas exchange. Because alveoli in dependent regions of the lungs expand more per unit change in transpulmonary pressure (Le., are more compliant) than alveoli in nondependent regions of the lungs, V A increases from the top to the bottom of the lungs. Because pulmonary blood flow increases more from the top to the bottom of the lungs than does V A, the ventilation/perfusion ratio is high in non dependent regions of the lungs and is low in dependent regions of the lungs. Therefore, in the upright lungs, the PA02 and pH are greater at the apex, whereas the PAC02 is greater at the base
A 38-year-old primiparous patient with placenta previa and active vaginal bleeding arrives in the OR with a systolic blood pressure of 85 mm Hg. A cesarean section is planned. The patient is lightheaded and scared. Which of the following anesthetic induction plans would be most appropriate for this patient? A. Spinal anesthetic with 12 to 15 mg bupivacaine. B. Epidural anesthetic with 20 to 25 mL 3% 2-chloroprocaine. C. General anesthetic induction with 3 to 4 mg/kg thiopental, intubation with 1 to 1.5 mg/kg succinylcholine. D. General anesthesia induction with 0.5 to 1 mglkg. ketamine, intubation with 1 to 1.5 mglkg succinylcholine E. Replace lost blood volume first, then use any anesthetic the patient wishes.
(D)Placenta previa occurs when the placenta implants on the lower uterine segment so that all (total) or part of the placenta (partial) covers the internal cervical os. A marginal placenta previa occurs when the placenta lies close to but does not cover the internal cervical os. It occurs in about 0.5% of all pregnancies and has a maternal mortality less than 1 % but a fetal mortality approaching 20% (primarily because of prematurity and intrauterine asphyxia). Patients typically present with painless vaginal bleeding that stops spontaneously (first bleed). Delivery is cesarean and is often made a few weeks after the "first" bleed when the baby's lungs mature more. A later bleed can be uncontrolled and accompanied by significant hypovolemia and hypotension. Regional anesthesia is contraindicated in severely hypovolemic patients. Replacing blood loss may not be practical because bleeding may be quicker than replacement is possible. A rapid-sequence general anesthetic (assuming acceptable airway) is preferred. Ketamine supports the cardiovascular system better than does thiopental or propofol. In rare but severe cases of hypovolemic shock, IV anesthetics may not be needed.
Sickle hemoglobin: (Select 2) A-has a lower P50 than hemoglobin A B-releases oxygen less readily than hemoglobin A C-is present in about 30% of African Americans D-readily polymerizes and precipitates in the red cell E-results from a single amino acid substitution on the α-chain F- has decreased solubility as compared to hemoglobin A
(D, F) readily polymerizes and precipitates in the red cell, has decreased solubility as compared to hemoglobin A Sickle hemoglobin (HbS) has a lower affinity for oxygen and an elevated P50 (31 mm Hg) as compared to hemoglobin A (27 mm Hg). HbS also has decreased solubility and readily polymerizes and precipitates in the red cell producing the sickled appearance of the cell. HbS results from the substitution of valine for glutamic acid on the β-chain.
Calculate the cardiac output from the following data: patient weight 70 kg; hemoglobin concentration 10 mg/dL; arterial blood gases on 100% 02: Páo 450 mm Hg, Pacó 32 mm Hg, pH 7.46, Sáo 99%; mixed venous blood gases: Pvó 30 mm Hg, Pacó 45 mm Hg, pH 7.32, Svó 60% . A. 2.5 Umin B. 3.0 Umin C. 3.5 L/min D. 4.0 L/min E. 4.5 L/min
(E) The Fick equation can be used to calculate cardiac output (Q) if the patient's 02 consumption (V02), arterial Ó content (Ca02), and mixed venous 02 content (Cv02) are determined. The downfalls of this type of Q measurement are threefold: (1) sampling and analysis errors in V02, (2) changes in Q while samples are being taken, and (3) accurate determination of V02 may be difficult because of cumbersome equipment. The Fick equation is as follows
Which of the following antidysrhythmic agents should not be used to treat wide complex tachycardia of indeterminate origin? A. Adenosine B. Lidocaine C. Procainamide D. Bretylium E. Verapamil
(E) A wide complex tachycardia of indeterminate origin may be paroxysmal supraventricular tachycardia with aberrant conduction through an accessory pathway, such as in patients with Wolff-Parkinson-White syndrome. In these situations, verapamil would decrease atrioventricular conduction through the AV node, thus allowing conduction of electrical impulses from the atria to the ventricle exclusively via the accessory pathway. This may result in exacerbation of the ventricular rate, which may lead to hemodynamic instability
A 170-J.Lm filter must be used for administration of each of the following EXCEPT A. Fresh frozen plasma B. Cryoprecipitate C. Platelets D. Packed red cells E. Albumin
(E) At the time of collection, an anticoagulant is added to donor blood. Nonetheless, small clots will occasionally form in the units, requiring filtration at the time of transfusion. A 170-lJ.m filter is present in standard blood administration sets for this purpose. Those filters permit rapid transfusion and should be used for infusions of platelets, fresh frozen plasma, cryoprecipitate, red blood cells, and granulocyte concentrates. Albumin does not need to be administered through a 170-lJ.m filter because it does not contain blood clots (
The neuromuscular effects of an intubation dose of vecuronium are terminated by: A. Pseudocholinesterase B. Nonspecific plasma cholinesterases C. The kidneys D. The liver E. Diffusion from the neuromuscular junction back into the plasma
(E) The effects of nondepolarizing neuromuscular drugs is based on the drug being at the receptor. After intravenous injection of a muscle relaxant, plasma drug concentration immediately starts to decrease. To produce paralysis, the drug must diffuse from the plasma to the neuromuscular junction after injection and bind to the receptors. The drug effect is later terminated by diffusion of drug back into the plasma. Recovery of neuromuscular function occurs when the muscle relaxant diffuses from the neuromuscular junction back into the plasma to be metabolized and/or eliminated from the body.
Which of the following antidysrhythmic agents should not be used to treat wide complex tachycardia of indeterminate origin? A. Adenosine B. Lidocaine C. Procainamide D. Bretylium E. Verapamil
(E) A wide complex tachycardia of indeterminate ongm may be paroxysmal supraventricular tachycardia with aberrant conduction through an accessory pathway, such as in patients with Wolff-Parkinson-White syndrome. In these situations, verapamil would decrease atrioventricular conduction through the AV node, thus allowing conduction of electrical impulses from the atria to the ventricle exclusively via the accessory pathway. This may result in exacerbation of the ventricular rate, which may lead to hemodynamic instability.
Which of the following antidysrhythmic agents should not be used to treat wide complex tachycardia of indeterminate origin? A. Adenosine B. Lidocaine C. Procainamide D. Bretylium E. Verapamil
(E) A wide complex tachycardia of indeterminate origin may be paroxysmal supraventricular tachycardia with aberrant conduction through an accessory pathway, such as in patients with Wolff-Parkinson-White syndrome. In these situations, verapamil would decrease atrioventricular conduction through the AV node, thus allowing conduction of electrical impulses from the atria to the ventricle exclusively via the accessory pathway. This may result in exacerbation of the ventricular rate, which may lead to hemodynamic instability
After placement of an epidural catheter in a 55-year-old patient for total hip arthroplasty, an entire epidural dose is administered into the subarachnoid space. Physiologic effects consistent with subarachnoid injection of large volumes of local anesthetic include: (Choose all that apply) I. Hypotension 2. Bradycardia 3. Apnea 4. Dilated pupils
(E) ALL Blockade of the sympathetic fibers (TI-L2) produces hypotension, particularly if the patient is hypovolemic. Bradycardia is produced by blocking the cardiac accelerator fibers (TI-T4). The phrenic nerve (C3-C5) is also blocked by a total spinal anesthetic. The pupils become dilated after intrathecal injection of large quantities of local anesthetics; they will return to normal size after the block recedes.
A 28-year-old, 70-kg woman with ulcerative colitis is undergoing general anesthesia for colon resection and ileostomy. Current medications include sulfasalazine and corticosteroids. Induction of anesthesia and tracheal intubation are uneventful. Anesthesia is maintained with isoflurane, N20 and 50% Ó, and fentanyl, and the patient is paralyzed with atracurium. The patient's lungs are mechanically ventilated with the following parameters: VE 5000 mL and respiratory rate 10 breaths/min. Assuming no change in VE how would VA change if the respiratory rate were increased from 10 to 20 breaths/min? A. Increase by 500 mL B. Increase by 1000 mL C. No change D. Decrease by 750 mL E. Decrease by 1500 mL
(E) Also see explanation to questions 103 and 134. A patient with a Vo of 150 mL and a VA of 350 mL (assuming a nonnal VT of 500 mL) will have a Vo minute ventilation (Vo) of 1500 mL and a VA minute ventilation (VA) of 3500 mL (VE of 5000 mL) at a respiratory rate of 10 breaths/min. If the respiratory rate is doubled but VE remains unchanged, then the Vo would double to 3000 mL and there would be an increase in Vo of 1500 mL and decrease in VA of 1500 mL
A 32-year-old parturient with a history of severe asthma and pregnancy-induced hypertension is brought to the operating room (OR) wheezing and needs an emergency cesarean section under general anesthesia. Which of the following induction agents would be most appropriate for this induction? A. Etomidate B. Midazolam C. Ketamine D. Thiopental E. Propofol
(E) Asthma occurs in about 4% of all pregnancies. When inducing general anesthesia in an asthmatic patient, it is imperative to establish an adequate depth of anesthesia before placing an endotracheal tube. If the patient is "light," then severe bronchospasm may occur. In patients with mild asthma, induction may work with any of these drugs. In a patient with severe asthma, ketamine or propofol is preferred. Because propofol does not stimulate the cardiovascular system as does ketamine, propofol would be preferred in this patient with pregnancy-induced hypertension. In patients with mild asthma who do not need the accessory muscles of respiration, regional anesthesia should be strongly considered because it would eliminate the need for endotracheal intubation.
Which of the following lung volumes or capacities change the LEAST during pregnancy? A. Tidal volume. B. Functional residual capacity. C. Expiratory reserve volume. D. Residual volume. E. Vital capacity.
(E) At term pregnancy, tidal volume (TV) increases about 40% to 45% and the inspiratory reserve volume (IRV) increases about 5%. A decrease occurs in both the expiratory reserve volume (ERV) 20% to 25% and the residual volume (RV) 15% to 20%. A capacity is defined as two or more lung volumes. Functional residual capacity (FRC = ERV + RV) is decreased about 15% to 20% and is partly responsible for the rapid fall in maternal oxygenation that occurs with apnea during the induction of general anesthesia. Total lung capacity (TLC = TV + IRV + ERV + RV) decreases about 5%, whereas vital capacity (VC = TV + IRV + ERV) remains unchanged.
Which of the following combinations would result in delivery of a higher-than-expected concentration of volatile anesthetic to the patient? A. Halothane vaporizer filled with sevoflurane. B. Halothane vaporizer filled with isoflurane. C. Isoflurane vaporizer filled with halothane. D. Isoflurane vaporizer filled with sevoflurane. E. Sevoflurane vaporizer filled with halothane .
(E) Because halothane and isoflurane have similar saturated vapor pressures, the vaporizers for these volatile anesthetics could be used interchangeably with accurate delivery of the anesthetic concentration set by the vaporizer dial. If a sevoflurane vaporizer were filled with a volatile anesthetic that has a greater saturated vapor pressure than sevoflurane (e.g., halothane or isoflurane), a higher-than-expected concentration would be delivered from the vaporizer. If a halothane or isoflurane vaporizer were filled with a volatile anesthetic that had a lower saturated vapor pressure than halothane or isoflurane (e.g., sevoflurane, enflurane, or methoxyflurane), a lower-thanexpected concentration would be delivered from the vaporizer.
Which of the following valves prevents transfilling between compressed-gas cylinders? A. Fail-safe valve B. Pop-off valve C. Pressure-sensor shutoff valve D. Adjustable pressure-limiting valve E. Outlet check valve
(E) Check valves permit only unidirectional flow of gases. These valves prevent retrograde fl ow of gases from the anesthesia machine or the transfer of gas from a compressed-gas cylinder at high pressure into a container at a lower pressure. Thus, these unidirectional valves will allow an empty compressed-gas cylinder to be exchanged for a full one during operation of the anesthesia machine with minimal loss of gas. The adjustable pressure-limiting valve is a synonym for a pop-off valve. A fail-safe valve is a synonym for a pressure-sensor shutoff valve. The purpose of a failsafe valve is to discontinue the flow of N0O if the 02 pressure within the anesthesia machine falls below 25 psi.
Each of the following is decreased in elderly patients compared with their younger counterparts EXCEPT A. Páo B. FEV. C. Ventilatory response to hypercarbia D. Vital capacity E. Closing volume
(E) Closing volume Aging is associated with reduced ventilatory volumes and capacities, and decreased efficiency of pulmonary gas exchange. These changes are caused by progressive stiffening of cartilage and replacement of elastic tissue in the intercostal and intervertebral areas, which decreases compliance of the thoracic cage. In addition, progressive kyphosis or scoliosis produces upward and anterior rotation of the ribs and sternum, which further restricts chest wall expansion during inspiration. With aging, the PRC, residual volume, and closing volume are increased, whereas the vital capacity, total lung capacity, maximum breathing capacity, FEV I' and ventilatory response to hypercarbia and hypoxemia are reduced. In addition, age-related changes in lung parenchyma, alveolar surface area, and diminished pulmonary capillary bed density cause ventilation/perfusion mismatch, which decreases resting Páo.
A 7 1-year-old man is undergoing revascularization of three coronary vessels on cardiopulmonary bypass at 28°C. After the first graft is sewn into the aorta, the arterial pressure measured from a left radial artery is 47 mm Hg and the pulmonary artery pressure is 6 mm Hg. Thirty minutes later the arterial pressure is 52 mm Hg and pulmonary artery pressure is 3 1 mm Hg. The most likely explanation for this is A. Malposition of the aortic cannula B. Malposition of the venous cannula C. Faulty ventricular venting D. Bypass associated sympathetic nervous system stimulation E. Pulmonary artery catheter migration
(E) During cardiopulmonary bypass, it is common for a pUlmonary artery catheter to migrate distally 3 to 5 cm into the pulmonary artery. In fact, pulmonary artery catheter migration during cardiopulmonary bypass is so common that withdrawing the catheter 3 to 5 cm before the initiation of cardiopulmonary bypass may be routinely indicated. Distal catheter migration into a wedge position is often detected by noting an increase in the measured pulmonary artery pressure. Pulmonary artery catheter migration during cardiopulmonary bypass has been implicated in cases of pulmonary artery rupture. Although catheter migration is the most likely explanation for a rise in pulmonary artery pressure during cardiopulmonary bypass, the anesthesiologist must also consider inadequate ventricular venting as a potential cause of increasing pulmonary artery pressures during cardiopulmonary bypass, particularly if the pulmonary artery pressure does not decline after withdrawal of the pulmonary artery catheter from a presumed wedge position. Ventricular distention during cardiopulmonary bypass is detrimental because it can increase myocardial oxygen demand at a time when there is no coronary blood flow. Malposition of the aortic cannula may result in unilateral facial blanching. Malposition of the venous cannula may result in facial or scleral edema or may manifest as poor blood return to the cardiopulmonary bypass circuit.
The most frequent cause of mechanical failure of the anesthesia delivery system to deliver adequate Ó to the patient is A. Attachment of the wrong compressed-gas cylinder to the Ó yoke. B. Crossing of pipelines during construction of the OR C. Improperly assembled Ó rotameter. D. Fresh-gas line disconnection from the anesthesia. machine to the in-line hosing. E. Disconnection of the Ó supply system from the patient.
(E) Failure to oxygenate patients adequately is the leading cause of anesthesia-related morbidity and mortality. All of the choices listed in this question are potential causes of inadequate delivery of 02 to the patient; however, the most frequent cause is inadvertent disconnection of the 02 supply system from the patient (e.g., disconnection of the patient breathing circuit from the endotracheal.
At high altitudes, the flow of a gas through a rotameter will be A. Greater than expected. B. Less than expected . C. Greater than expected at high flows but less than expected at low flows D. Less than expected at high flows but greater than expected at low flows. E. Greater than expected at high flows but accurate at low flow.
(E) Gas density decreases with increasing altitude (i.e., the density of a gas is directly proportional to atmospheric pressure). Atmospheric pressure will influence the function of rotameters (see explanation to question 54) because the accurate function of rotameters is influenced by the physical properties of the gas, such as density and viscosity. The magnitude of this influence, however, depends on the rate of gas flow. At low gas flows, the pattern of gas flow is laminar. Atmospheric pressure will have little effect on the accurate function of rotameters at low gas flows (see explanation to question 43) because laminar gas flow is influenced by gas viscosity (which is minimally affected by atmospheric pressure) and not gas density. However, at high gas flows, the gas flow pattern is turbulent and is influenced by gas density (see explanation to question 2). At high altitudes (Le., low atmospheric pressure), the gas flow through the rotameter will be greater than expected at high flows but accurate at low flows.
The advantage of infusing Hetastarch (hydroxyethyl starch) over dextran 70 for volume replacement is that hetastarch A. Is not associated with allergic reactions B. Is less likely to cause hypervolemia C. Does not interfere with coagulation D. Does not need to be administered through a 1 70-~m fi lter. E. Does not interfere with blood typing and crossmatching
(E) Hetastarch (hydroxyethyl starch) and dextran 70 (glucose polymers with mean molecular weights of 70,000) are colloid solutions that are used for intravascular fluid volume expansion. Both hetastarch and dextran have been associated with allergic reactions, can interfere with coagulation, and can cause hypervolemia. Hetastarch, unlike dextrans, does not interfere with crossmatching of blood at the recommended maximal daily dose of 20 mL/kg. Neither compound needs to be administered through a filter.
Cardiac output is greatest A. During the first trimester of pregnancy B. During the second trimester of pregnancy C. During the third trimester of pregnancy D. During labor E. Immediately after delivery of the newborn
(E) Immediately after delivery, the cardiac output can increase up to 75% to 80% above prelabor values. This is thought to result from autotransfusion and increased venous return to the heart associated with involution of the uterus.
In an emergency when there is a limited supply of type O-negative RBCs, type O-positive RBCs are reasonable for transfusion for each of the following patients EXCEPT A. A 60-year-old woman with diabetes who was involved in a motor vehicle accident B. A 23-year-old man who sustained a gunshot wound to the upper abdomen C. A 84-year-old man with a ruptured abdominal aortic aneurysm D. A 5-year-old boy involved in a pedestrian automobile accident E. A 21-year-old, gravida 2, para 1 woman with placenta previa who is bleeding profusely.
(E) In an emergency when massive amounts of blood are immediately required and the supply of O-negative RBCs in the blood bank is low, it is acceptable to transfuse O-positive RBCs into male patients or into female patients past the age of childbirth before the patient's blood typing is known. This is because delaying blood transfusion for blood typing may be more hazardous to the patient than the risk of a significant transfusion reaction based on Rh type for these patients. However, for the female patient who has the potential for pregnancy, administration of Rh-positive RBCs is not recommended (unless no Rh-negative RBCs are available). This is because an Rh-negative patient who receives Rh-positive RBCs would develop isoimmunization. For these women, future pregnancies with Rh-positive fetuses could be associated with erythroblastosis fetalis. Note: RBCs are preferred over whole blood because Rh-negative whole blood contains a large quantity of anti-A and anti-B antibodies in the plasma.
What effect does thiopental have on the CÓ responsiveness of the cerebral vasculature? A. Thiopental attenuates the effect of hypocarbia on CBF B. Thiopental attenuates the effect of hypercarbia on CBF C. Thiopental augments the effect of hypercarbia on CBF D. Thiopental augments the effect of hypocarbia on CBF E. Thiopental does not affect CÓ reactivity at a dose used clinically.
(E) In general, the cerebrovascular response to changes in Pacó is preserved after the administration of intravenous anesthetics. Specifically, in humans, CÓ reactivity is maintained with barbiturate concentrations sufficient to produce burst suppression on the EEG.
The most common injury in obstetric anesthetic claims is A. Headache B. Pain during anesthesia C. Neonatal death D. Maternal brain damage E. Maternal death
(E) In obstetric claims, the mean maternal age is 28 years. Seventy-one percent of cases involve cesarean section and 29% vaginal deliveries. Of the obstetric claims, 67% were associated with regional anesthesia and 31 % with general anesthesia. The most common injury was maternal death, which comprised 19% of claims. Next was neonatal brain damage, which was slightly less but also 19%. Fifteen percent of claims involved headache, 10% maternal nerve damage, 9% pain during anesthesia, 8% back pain, 7% maternal brain damage, 7% emotional distress, 6% neonatal death, and 5% aspiration pneumonitis.
A 4-year-old child with tetralogy of Fallot is to undergo elective repair of a left inguinal hernia under general anesthesia. Which of the following anesthetics would provide the most stable hemodynamics in this patient? A. Halothane and N20 B. Enfturane and N20 C. Halothane D. Fentanyl and N20 E. Ketamine
(E) In patients with tetralogy of Fallot, it is important to maintain systemic vascular resistance to reduce the magnitude of the right-to-Ieft intracardiac shunt. Therefore, induction of anesthesia in these patients is best accomplished with ketamine 3 to 4 mglkg 1M or 1 to 2 mglkg IV. Ketamine will usually improve arterial oxygenation, which reflects increased pulmonary blood flow due to ketamine-induced increases in systemic vascular resistance.
While on cardiopulmonary bypass during elective coronary artery revascularization, the patient is noted to have bulging sclerae. Mean arterial pressure is 50 mm Hg, temperature is 28°C, and there is no ECG activity. The most appropriate action to take at this time is to: A. Administer mannitol, 50 gm IV B. Administer furosemide, 20 mg IV C. Decrease the cardiac index D. Check the position of the aortic cannula E. Check the position of the venous return cannula
(E) Incorrect positioning of the aortic perfusion and venous return cannulae are possible complications associated with cardiopulmonary bypass. Improper postioning of the aortic cannula would tend to result in unilateral facial blanching, whereas facial edema (e.g., bulging sclerae) reflects venous congestion and may be caused by improper positioning of the venous return canula. Incorrect positioning of the venous return cannula can occur when the cannula is inserted too far into the superior vena cava, which causes obstruction of the right innominate vein. If the venous cannula is inserted too far into the inferior vena cava, venous return from the lower regions of the body can be impaired and abdominal distention can occur. If this happens, the vena caval cannula should be withdrawn to a more proximal position and the adequacy of the venous return from the patient to the cardiopulmonary bypass machine should be confirmed. A properly positioned venous return cannula will bleed back with nonpulsatile flow when the proximal end is lowered below the patient.
Each of the following will alter the position or slope of the CÓ-ventilatory response curve EXCEPT A. Hypoxemia B. Fentanyl C. N20 D. Volatile anesthetics E. Ketamine
(E) Ketamine. Measuring the ventilatory response to increased Pacó is a sensitive method for quantifying the effects of drugs on ventilation. In general, all volatile anesthetics (including N20), narcotics, benzodiazepines, and barbiturates depress the ventilatory response to increased Pacó in a dose-dependent manner. The magnitude of ventilatory depression by volatile anesthetics is greater in patients with COPD than in healthy patients. ABGs may need to be monitored during recovery from general anesthesia in patients with COPD. Ketamine causes minimal respiratory depression. Typically, respiratory rate is decreased only 2 to 3 breaths/min and the ventilatory response to changes in Pacó is maintained during ketamine anesthesia.
Which of the following pharmacologic agents would have the LEAST effect on transcranial motor evoked potentials? A. Isoflurane B. Nitrous oxide C. Etomidate D. Diazepam E . Fentanyl.
(E) Limitations in somatosensory evoked potential monitoring have prompted interest in monitoring the motor system. Specifically, motor evoked potentials (MEPs) are used to monitor the integrity of motor pathways in the nervous system during neurosurgical, orthopedic, or major vascular (e.g., procedures that involve cross-clamping of the thoracic aorta) surgery. Electrical or magnetic stimulation of the motor cortex produces an evoked potential that is propagated via descending motor pathways and can be recorded from the spinal epidural space, spinal cord, peripheral nerve, or the muscle itself. In general, inhalation and intravenous anesthetics decrease the amplitude and increase the latency of the MEP response. Fentanyl is an exception to this rule and has little, if any, effect on MEP monitoring.
Which of the following would have the greatest effect on the level of sensory blockade after a subarachnoid injection of isobaric 0.75% bupivacaine? A. Coughing during placement of the block B. Addition of epinephrine to the local anesthetic solution C. Barbotage D. Patient weight E. Patient position
(E) Many factors have an effect on the sensory level after a subarachnoid injection. The baricity of the solution and the patient position are the most important determinants of sensory level. The other listed options have little to no effect on sensory level. Patient height also has little effect on sensory level.
A 24-year-old gravida 2, para 1 parturient is anesthetized for emergency cesarean section. On emergence from general anesthesia, the endotracheal tube is removed and the patient becomes cyanotic. Oxygen is administered by positive-pressure mask-bag ventilation. High airway pressures are necessary to ventilate the patient, and wheezing is noted over both lung fields. The patient's blood pressure falls from 120/80 to 60130 mm Hg, and heart rate increases from 105 to 180 beats/min. The most likely cause of these manifestations is A. Venous air embolism B. Amniotic fluid embolism C. Mucous plug in trachea D. Pneumothorax E. Aspiration
(E) Many of the signs are consistent with the choices described in this question. From the temporal perspective, gastric acid aspiration is the most likely cause. Morbidity and mortality occurring after gastric acid aspiration is determined by both the amount and the pH of the aspirated material. Aspiration of a gastric volume greater than 0.4 mLlkg with a pH less than 2.5 causes severe pneumonitis with high morbidity and mortality. Using these values, 70% of women who fasted before elective cesarean section are "at risk for aspiration." Recently it has been noted that the volume needed to cause aspiration in primates should be 0.8 mL/kg and the pH less than 3.5. Regardless of the definition of the "patient at risk," when aspiration occurs it can be lethal. Bronchospasm and wheezing are suggestive of gastric acid aspiration and not amniotic fluid embolism. Other signs and symptoms of aspiration include sudden coughing or laryngospasm, dyspnea, tachypnea, the presence of foreign material in the mouth or posterior pharynx, chest wall retraction, cyanosis not relieved by oxygen supplementation, tachycardia, hypotension, and the development of pinky frothy exudates. The onset of these signs and symptoms is usually rapid. Early treatment with positive-pressure ventilation and PEEP or continuous positive airway pressure decreases the incidence of mortality from acid aspiration.
Which of the following statements regarding the newborn with thick meconium-stained amniotic fluid is TRUE? A. Intubation is required for all such newborns. B. Antibiotics are needed to treat the infection. C. Steroids are needed to treat the inflammation. D. Respiratory distress syndrome is common. E. Surfactant is useful in severe cases.
(E) Meconium-stained amniotic fluid occurs in about 10% of all deliveries. For many years it was suggested that all newborns with thick meconium-stained fluid be intubated and the trachea suctioned. In the last few years it has been suggested that intubation and tracheal suction should only be performed in newborns who are not vigorous (Le., does not depend upon the consistency of the meconium-stained fluid). In newborns who are vigorous (i.e., strong respiratory efforts, good muscle tone, and heart rate >100 beats/min), routine oral and nasal suctioning with a suction bulb is all that is needed. Because meconium is sterile, antibiotics are not needed. Steroids have not been necessary in the treatment of meconium-stained newborns. Respiratory distress syndrome (RDS) is a condition that occurs as a result of low levels of pulmonary surfactant in the alveoli. RDS occurs in premature newborns, whereas meconium staining occurs typically in the older often postterm newborns. Surfactant has been used with success to loosen the thick meconium in some newborns with severe respiratory distress and may lessen the need for extracorporeal membrane oxygenation (EcMO) .
Which of the following intravenous anesthetics is contraindicated in patients with intracranial hypertension? A. Diazepam B. Fentanyl C. Thiopental D. Midazolam E. Ketamine
(E) Of the choices listed in this question, ketamine is the only intravenous anesthetic not recommended for patients with intracranial hypertension because it increases cerebral metabolic rate (CMR), cerebral blood flow (CBF), cerebral blood volume (CBV), and ICP. Barbiturates, etomidate, and propofol decrease CMR, CBF, CBV, and ICP. All three of these agents indirectly decrease CBF by their inhibitory effect on CMR. However, unlike thiopental, etomidate also has a direct vasoconstrictor effect on the cerebral vasculature. One potential advantage of etomidate over thiopental is that it does not produce significant cardiovascular depression. Although not as pronounced as the barbiturates, benzodiazepines such as midazolam also reduce CMR and CBF. Flumazenil, a benzodiazepine antagonist, has been reported to reverse the effect of midazolam on CMR, CBF, CBV, and ICP. Consequently, flumazenil should be avoided in midazolamanesthetized patients known to have intracranial hypertension. Generally speaking, the opioid anesthetics, such as morphine and fentanyl, cause either a minor reduction or have no effect on CBF and CMR.
A 28-week estimated gestational age (EGA), 1000-g male infant is born to a 24-year-old mother who is addicted to heroin. The mother admits taking an extra "hit" of heroin before coming to the hospital because she was nervous. The infant's respiratory depression would be best managed by A. 0.1 mg naloxone IV through an umbilical artery catheter. B. 0.1 mg naloxone 1M in the newborn's thigh muscle C. 0.1 mg naloxone down the endotracheal tube D. 0.4 mg naloxone 1M to the mother during the second stage of labor E. None of the above
(E) Opioid abuse includes morphine, heroin, methadone, meperidine, and fentanyl. The problems associated with abuse are many and include the drug effect itself, substances mixed with the narcotics (e.g., talc, com starch), as well as infection and malnutrition. Newborn respiratory depression as manifested by a low respiratory rate is treated with controlled ventilation but not with naloxone. Naloxone can precipitate an acute withdrawal reaction and should not be administered to patients with chronic narcotic use (mother or newborn). The dose of naloxone to treat narcotic-induced respiratory depression in the nonaddicted newborn is 0.1 mg/kg
Allodynia is defined as: A. Spontaneous pain in an area or region that is anesthetic B. Pain initiated or caused by a primary lesion or dysfunction in the nervous system C. An unpleasant abnormal sensation, whether spontaneous or evoked D. An increased response to a stimulus that is normally painful E. Pain caused by a stimulus that does not normally provoke pain
(E) Pain caused by a stimulus that does not normally provoke pain. The International Association for the Study of Pain (IASP) has defined several pain terms. Anesthesia dolorosa refers to spontaneous pain in an area or region that is anesthetic. Neuropathic pain is pain initiated or caused by a primary lesion or dysfunction in the nervous system. Dysesthesia is an unpleasant abnormal sensation, whether spontaneous or evoked. Hyperalgesia is an increased response to a stimulus that is normally painful. Allodynia is pain caused by a stimulus that does not normally provoke pain
A 57-year-old patient is scheduled for hemorrhoidectomy. The patient has a history of mild chronic obstructive pulmonary disease, hypertension, and traumatic foot amputation from a tractor accident. His only hospitalizations were for two suicide attempts related to excruciating phantom limb pain that resolved 10 years ago. He takes phenelzine (Nardil), thiazide, and potassium. Which of the following anesthetic techniques would be most appropriate for this patient? A. Spinal anesthetic with 0.5% hyperbaric bupivacaine B. Epidural anesthetic with 0.5% bupivacaine C. Local infiltration with lidocaine and epinephrine, sedation with propofol and meperidine D. General anesthesia with Pentothal, succinylcholine, nitrous oxide, isoflurane, meperidine E. General anesthesia with propofol, succinylcholine, nitrous oxide, fentanyl.
(E) Reactivation of phantom limb pain has been reported in patients who have received both spinal and epidural anesthetics. With a history of a painful phantom limb so severe as to drive a patient to attempt suicide, it is probably wise to avoid spinal and epidural anesthetics. Any anesthetic or combination of techniques that involves meperidine is contraindicated in patients receiving monoamine oxidase inhibitors. The combination of meperidine and monoamine oxidase inhibitors has been associated with hypothermia, hypotension, hypertension, ventilatory depression, skeletal muscle rigidity, seizures, and coma. Because of this unfavorable drug interaction, meperidine should be avoided in patients receiving monoamine oxidase inhibitors. Accordingly, the only acceptable anesthetic in this question would be general anesthesia with propofol, succinylcholine, nitrous oxide, and fentanyl.
567. A 2-month-old infant with a strong family history of sickle cell anemia is brought to the emergency room with an incarcerated inguinal hernia. Which of the following should be carried out before surgery? A. Sickle cell prep B. Hemoglobin electrophoresis C. Peripheral smear D. Hematology consultation E. None of the above
(E) Sickle cell anemia (hemoglobin SS) is an inherited disorder of the [3-chain of the hemoglobin molecule caused by a single amino acid substitution. It has a incidence of about 0.2% in the African American population in contrast to the relatively benign heterozygous condition, sickle cell trait (hemoglobin AS), which affects 8% to 10% of the same group. Sickling can occur in homozygous patients who become hypoxic, acidotic, hypothermic, or dehydrated. The predominant hemoglobin species in a 2-mol1lh-old infant, however, is hemoglobin F (fetal hemoglobin), which would temporarily protect the infant from the manifestations of sickle cell anemia were he or she homozygous for hemoglobin S. The patient should, however, be worked up for sickle cell anemia at some point in early life, but such a workup is not a prerequisite for surgery at age 2 months.
Which of the following pharmacologic agents would have the LEAST effect on somatosensory evoked potentials? A. Isoflurane B. Nitrous oxide C. Sodium thiopental D. Etomidate E. Vecuronium
(E) Somatosensory evoked potentials (SSEPs) are used to monitor the integrity of sensory pathways in the nervous system during neurosurgical or orthopedic surgery (also see explanation to question 761). Volatile anesthetics (e.g., isoflurane) and barbiturates (e.g., sodium thiopental) decrease the amplitude and increase the latency of SSEP waveforms. Nitrous oxide decreases the amplitude but has no effect on latency. Etomidate increases both the amplitude and latency. In contrast, nondepolarizing muscle relaxants (e.g., vecuronium) have no effect on sensory pathways of the nervous system and, thus, can be used during SSEP monitoring.
The maximum FI02 that can be delivered by a nasal cannula is A. 0.25 B. 0.30 C. 0.35 D. 0.40 E. 0.45
(E) The FI02 delivered to patients from low-flow systems (e.g., nasal prongs) is determined by the size of the 02 reservoir, the Ó flow, and the patient's breathing pattern. As a rule of thumb, assuming a normal breathing pattern, the FI02 delivered by nasal prongs increases by approximately 0.04 for each min increase in 02 flow up to a maximal FI02 of approximately 0.45 (at an 02 flow of 6 L/min). In general, the larger the patient's VT or faster the respiratory rate, the lower the FIó for a given 02 flow.
Calculate the cardiac output from the following data: patient weight 70 kg; hemoglobin concentration 10 mg/dL; arterial blood gases on 100% 02: Páo 450 mm Hg, Pacó 32 mm Hg, pH 7.46, Sáo 99%; mixed venous blood gases: Pvó 30 mm Hg, Pacó 45 mm Hg, pH 7.32, Svó 60%. A. 2.5 Umin B. 3.0 Umin C. 3.5 L/min D. 4.0 L/min E. 4.5 L/min
(E) The Fick equation can be used to calculate cardiac output (Q) if the patient's 02 consumption (V02), arterial Ó content (Ca02), and mixed venous 02 content (Cv02) are determined. The downfalls of this type of Q measurement are threefold: (1) sampling and analysis errors in V02, (2) changes in Q while samples are being taken, and (3) accurate determination of V02 may be difficult because of cumbersome equipment.
Allodynia is defined as : A. Spontaneous pain in an area or region that is anesthetic B. Pain initiated or caused by a primary lesion or dysfunction in the nervous system C. An unpleasant abnormal sensation, whether spontaneous or evoked D. An increased response to a stimulus that is normally painful E. Pain caused by a stimulus that does not normally provoke pain.
(E) The International Association for the Study of Pain (IASP) has defined several pain terms. Anesthesia dolorosa refers to spontaneous pain in an area or region that is anesthetic. Neuropathic pain is pain initiated or caused by a primary lesion or dysfunction in the nervous system. Dysesthesia is an unpleasant abnormal sensation, whether spontaneous or evoked. Hyperalgesia is an increased response to a stimulus that is normally painful. Allodynia is pain caused by a stimulus that does not normally provoke pain
The mass spectrometer waveform above represents which of the following situations? A. Cardiac oscillations B. Kinked endotracheal tube C. Bronchospasm D. Incompetent inspiratory valve E. Incompetent expiratory valve
(E) The capnogram can provide a variety of information, such as verification of the presence of exhaled CÓ after tracheal intubation, estimation of the difference in Pacó and PETC02, abnormalities of ventilation, and the presence of hypercapnia or hypocapnia. The four phases of the capnogram are inspiratory baseline, expiratory upstroke, expiratory plateau, and inspiratory downstroke. The shape of the capnogram can be used to recognize and diagnose a variety of potentially adverse circumstances. Under normal conditions, the inspiratory baseline should be 0, indicating that there is no rebreathing of CÓ with a normal functioning circle breathing system. If the inspiratory baseline is elevated above 0, there is rebreathing of CÓ, If this occurs, the differential diagnosis should include an incompetent expiratory valve, exhausted CÓ absorbent, or gas channeling through the CÓ absorbent. However, the inspiratory baseline may be elevated when the inspiratory valve is incompetent (e.g., there may be a slanted inspiratory downstroke). The expiratory upstroke occurs when the fresh gas from the anatomic dead space is quickly replaced by CÓ-rich alveolar gas. Under normal conditions the upstroke should be steep; however, it may become slanted during partial airway obstruction, if a side stream analyzer is sampling gas too slowly, or if the response time of the capnograph is too slow for the patient's respiratory rate. Partial obstruction may be the result of an obstruction in the breathing system (e.g., by a kinked endotracheal tube) or in the patient's airway (e.g., the presence of chronic obstructive pulmonary disease or acute bronchospasm). The expiratory plateau is normally characterized by a slow but shallow progressive increase in CÓ concentration. This occurs because of imperfect matching of ventilation and perfusion in all lung units. Partial obstruction of gas flow either in the breathing system or in the patient's airways may cause a prolonged increase in the slope of the expiratory plateau, which may continue rising until the next inspiratory downstroke begins. The inspiratory downstroke is caused by the rapid influx of fresh gas, which washes the CÓ away from the CÓ sensing or sampling site. Under normal conditions the inspiratory downstroke is very steep. Causes of a slanted or blunted inspiratory downstroke include an incompetent inspiratory valve.
An anesthesia pain service consult is sought for a 78-year-old patient with a complaint of pain in the distribution of the trigeminal nerve. The patient has no other medical problems except a history of congestive heart failure for which he takes digoxin and thiazide. In addition to his chief complaint, the patient over the last 72 hours has complained of dysesthesia in the feet, difficulty with vision, and emesis times three. The most appropriate step at this time would be A. Trigeminal nerve block with bupivacaine B. Obtain neurologic workup for multiple sclerosis C. Administration of fentanyl and ondansetron D. Initiate therapy with carbamazepine E. Obtain a digoxin level .
(E) The early signs of digitalis toxicity include loss of appetite and nausea and vomiting. In some patients there may be pain that is similar to trigeminal neuralgia. Pain or discomfort in the feet and pain and discomfort in the extremities may be a feature of digitalis toxicity. Transient visual disturbances have been reported in patients with digitalis toxicity. In this patient, it would be prudent to obtain a digoxin level as an early part of the workup for these complaints. He may also have true trigeminal neuralgia, and workup for this condition can be undertaken after digitalis toxicity has been ruled out.
The most common complication associated with a supraclavicular brachial plexus block is A. Blockade of the phrenic nerve B. Intravascular injection into the vertebral artery C. Spinal blockade D. Blockade of the recurrent laryngeal nerve E. Pneumothorax
(E) The most common complication associated with a supraclavicular brachial plexus block is pneumothorax. Other potential complications include phrenic nerve paralysis, Horner's syndrome, nerve damage or neuritis, or intravascular injection.
The most common transfusion-associated infection in the United States is A. Syphilis B. Hepatitis B C. Hepatitis C D. Human immunodeficiency virus (HIV) E. Cytomegalovirus (CMV)
(E) The most common transfusion associated infection in the United States is CMV. Antibodies to CMV are found in 40% to 90% of asymptomatic patients and show that in most patients CMV infection is benign. However, in immunocompromised patients or premature newborns, CMV infection can be serious and at times fatal. Because CMV's infectious form is carried in white blood cells, transfusion of CMV-negative blood or blood that has been filtered to remove WBCs can be used. Risk of transfusion-transmitted infection with a unit of screened blood in the United States (1999 data) is less than 1% for CMV, 1 in 63,000 for hepatitis B, 1 in 103,000 for hepatitis C, 1 in 493,000 for HIV, and 1 in 641,000 for human T-celllymphotropic virus (HTLV). The infective agent for syphilis does not survive at 4°C, making transmission unlikely for whole blood, RBCs, fresh frozen plasma, or cryoprecipitate. It is possible for platelets (stored at room temperature) to transmit syphilis
An otherwise healthy 3-month-old black female infant with a hemoglobin of 19 mgldL at birth presents for elective repair of an inguinal hernia. Her preoperative hemoglobin is 10 mgldL. Her father has a history of polycystic kidney disease. The most likely explanation for this patient's anemia is A. Sickle cell trait B. Sickle cell anemia C. Iron deficiency D. Undiagnosed polycystic kidney disease E. It is a normal finding
(E) The most likely explanation for the "falling" hemoglobin level in this patient is that this is a normal physiologic finding. At birth, a full-term infant has a hemoglobin level of approximately 15 to 20 g/elL. A physiologic anemia occurs by age 2 to 3 months, resulting in hemoglobin concentrations of approximately 10 to 12 glelL. Mter 3 months, there is a progressive increase in hemoglobin concentration, which reaches levels similar to that of adults by age 6 to 9 months
A 29-year-old gravida 1, para 0 parturient at 10 weeks of gestation is to undergo an emergency appendectomy under general anesthesia with isoflurane, N20, and 02' Which of the following is a proven untoward consequence of general anesthesia in the unborn fetus? A. Nephroblastoma B. Cleft palate C. Mental retardation D. Behavioral defects E. None of the above
(E) The primary objectives in the anesthetic management of parturients undergoing general anesthesia for nonobstetric surgery are to (1) ensure maternal safety, (2) avoid teratogenic drugs, (3) avoid intrauterine fetal asphyxia, and (4) prevent the induction of preterm labor. Premature onset of labor is the most common complication associated with surgery during the second trimester of pregnancy. Performance of intra-abdominal procedures in which the uterus is manipulated is the most significant factor in causing premature labor in these patients. Neurosurgical, orthopedic, thoracic, or other surgical procedures that do not involve manipulation of the uterus do not cause pre term labor. No anesthetic agent or technique has been found to be significantly associated with a higher or lower incidence of preterm labor. Furthermore, there is no evidence that the risk of developing any of the conditions listed in this question is increased for the offspring of patients who receive general anesthesia during pregnancy.
Which of the following respiratory parameters is not increased in the parturient? A. Minute ventilation B. Tidal volume C. Arterial Páo D. Oxygen consumption E. Serum bicarbonate
(E) The respiratory system undergoes many changes during pregnancy with an increase in minute ventilation about4S% to SO%, tidal volume 40% to 4S%, and arterial Pao, increases slightly due to a fal l in Paco,. Oxygen consumption increases about 20% to 60%. The serum bicarbonate level falls an average of 4 mEq/L to keep pH in the normal range because of the respiratory alkalosis (Paco, to approximately 30 mm Hg) that occur.
An 18-year-old patient receiving subcutaneous heparin develops a Horner's syndrome on the left side after placement of an epidural for labor analgesia. On physical examination a T5 anesthetic level is noted, but aside from the Horner's syndrome no other findings are revealed. The most appropriate course of action at this time would be A. Remove the epidural B. Consult a neurosurgeon C. Obtain a computed tomographic scan D. Secure the airway E. None of the above
(E) This benign condition occasionally develops after a lumbar epidural anesthetic even when the highest dennatome level blocked is below T5. It may be related to the superficial anatomic location of the descending spinal sympathetic fibers that lie just below the spinal pia of the dorsolateral fu niculus, which is within diffusion range of subanesthetic concentrations of local anesthetics in the cerebrospinal fluid.
A 65-year-old male involved in a motor vehicle accident is brought to the emergency room with a blood pressure of 60 mm Hg. He is transfused with 4 units of type 0, Rh-negative whole blood and 4 L of lactated Ringer's solution. After the patient is brought to the operating room his blood type is determined to be A positive. Which of the following is the most appropriate blood type for further intraoperative transfusions? A. Type A, Rh-positive whole blood B. Type A, Rh-positive RBCs C. Type 0, Rh-positive whole blood D. Type 0, Rh-negative whole blood E. Type 0, Rh-negative RBCs
(E) Type 0, Rh-negative blood is also called universal donor blood because the transfused RBCs lacks the antigens needed to be hemolyzed. Because a-negative blood's plasma contains anti-A and anti-B antibodies, it is preferable to administer packed RBCs (with little plasma) over whole blood (lot of plasma) in an emergency. However, if two or more units of type a-negative, un-crossmatched whole blood are administered to a patient and subsequent blood typing reveals the patient's blood type to be A, B, or AB, then switching back to the patient's own blood type could lead to major intravascular hemolysis of the transfused RBCs and, therefore, is not advised. Use of type a-negative universal donor whole blood or preferably RBCs is recommended. In the male patient or the older female patient who will not have more children, type a-positive whole blood can be administered if few type 0, Rh-negative units are available and massive transfusion is anticipated. Only after it is determined that the patient has a low enough levels of transfused anti-A and anti-B antibodies should the correct type blood be administered.
Drugs useful in the treatment of uterine atony in an asthmatic with preeclampsia include A. Oxytocin, 15-methyl prostaglandin F2a (PGF2a) and ergonovine B. Oxytocin and 15-methyl PGF2a C. Oxytocin and ergonovine D. 15-methyl PGF2a only E. Oxytocin only
(E) Uterine atony is a common cause of postpartum hemorrhage. Treatment consists of uterine massage, drugs, and in rare cases hysterectomy. Drugs commonly used include oxytocin, ergot alkaloids (ergonovine, methylergonovine), and prostaglandins (PGÉ, PGF2a, I5-methyl PGF2a). The ergot alkaloids not infrequently cause elevations in blood pressure and are relatively contraindicated in patients with hypertension (such as preeclampsia). Ergot alkaloids have been associated with bronchospasm and may not be appropriate in asthmatics. The prostaglandin 15-methyl PGF2a (carboprost, Hemabate) is the only prostaglandin currently approved for uterine atony in the United States and may cause significant bronchospasm in susceptible patients
A venous blood sample from which of the following sites would correlate most reliably with Páo and Pacó? A. Jugular vein B. Subclavian vein C. Antecubital vein D. Femoral vein E. Vein on posterior surface of a warmed hand.
(E) When arterial sampling is not possible, "arterialized" venous blood can be used to estimate ABG tensions. Because blood in the veins on the back of the hands have very little Ó extracted, the Ó content in this blood best approximates the Ó content in a sample of blood obtained from an artery.
Select the FALSE statement regarding iatrogenic bacterial infections from anesthetic equipment. A. Even low concentrations of Ó are lethal to airborne bacteria. B. Bacteria that are released from the airway during violent exhalation originate almost exclusively from the anterior oropharynx C. Of all the bacterial forms, acid-fast bacteria are the most resistant to destruction D. Shifts in temperature and humidity are probably the most important factors responsible for bacterial killing E. Bacterial filters in the anesthesia breathing system lower the incidence of postoperative pulmonary infections.
(E). There is no evidence that the incidence of postoperative pulmonary infection is altered by the use of sterile disposable anesthesia breathing systems (compared with the use of reusable systems that are cleaned with basic hygienic techniques) or by the inclusion of a bacterial filter in the anesthesia breathing system.
A patient's blood type is to be determined. No agglutination is seen when the patient's blood is mixed with Anti-A antibody or Anti-B antibody. Agglutination is seen when the patient's blood is mixed with Anti-D antibody. Which ABO blood type PRBCs would be acceptable to administer to this patient? (A) A positive (AB) positive (B) positive (O) positive
(O) positive Many antigens are present on the surface of red blood cells. A and B antigens are capable of causing an antibody response that results in fatal intravascular hemolysis, whereas reaction of the D antigen with its antibody can cause hemolytic disease of the newborn. Red blood cells exist with one of 3 clinically important states: A antigen only, B antigen only, or neither the A or the B antigen. When a type and screen is performed, antibodies towards the A and B antigens are mixed with the patient's blood to check for agglutination, which will occur when the patient's blood contains the appropriate antigen. In the case above, no agglutination occurs with the mixture of either Anti-A or Anti-B antibodies to the patient's serum, indicating that the red blood cells do not have either A or B antigen on their surfaces (type O). Agglutination does occur with Anti-D antibody, however, so the Rh type of the patient is "positive," hence the patient is Type O positive. Because this patient has Type O positive blood, they must receive Type O blood. Because they do have the D antigen, though, they can receive either Rh positive or Rh negative blood.
In a term fetus the normal oxygen consumption is approximately A. 7 mL/min B. 14 mL/min C. 21 mL/min D. 32 mL/min E. 45 mL/min
(e) The normal term (approximately 3 kg) fetus has an oxygen consumption of 7 mL/kg/min or about 2 1 mL/min. Because the fetal store of oxygen is about 42 mL, in theory it would take 2 minutes to completely deplete it during an interruption in the normal blood supply of oxygen. In reality, the fetus has several compensatory mechanisms that allow it to survive for longer periods of time during periods of hypoxia
True statement(s) concerning peripheral nerve structure and function include which of the following?(Choose all that apply) 1. Both nonmyelinated and myelinated nerves are surrounded by Schwann cells 2. The speed of propagation of an action potential along a nerve axon is greatly enhanced by myelin 3. Generation of an action potential is an "all-or-nothing" phenomenon 4. Propagation of an action potential along myelinated nerve axons occurs by saltatory conduction via the nodes of Ranvier.
-All are correct. Peripheral nerve axons are always enveloped by a Schwann cell. The myelinated nerves may be enveloped many times by the same Schwann cell. Transmission of nerve impulses (i.e., action potentials) along nonmyelinated nerves occurs in a continuous fashion, whereas transmission along myelinated nerves occurs by saltatory conduction from one node of Ranvier to the next. Myelination speeds transmission of neurological impUlses; it also renders nerves more susceptible to local anesthetic blockade. An action potential is associated with an inward flux of sodium that occurs after a certain membrane threshold has been exceeded.
The perioperative use of a thoracic epidural with a local anesthetic solution is associated with A. The spinal reflex inhibition of the gastrointestinal (GI) tract remaining unaffected B . Similar pulmonary complications as intrapleural and intercostal block C. Attenuating spinal reflex inhibition of diaphragmatic function D. No effect in size of myocardial infarction compared to lumbar epidural E. No change in coronary blood flow
. ANSWER: C By inhibiting sympathetic outflow and attenuating spinal reflex inhibition of the GI tract, epidural analgesia can facilitate the return of GI tract motility. It has been shown that thoracic epidural analgesia with a local anesthetic decreases the incidence of pulmonary infections and complications compared with epidural opioids alone, wound infiltration with local anesthetic, intercostal blocks, and intrapleural analgesia. Thoracic epidural analgesia reduces splinting behavior and attenuates the spinal reflex inhibition of diaphragmatic function. It also decreases the severity and size of myocardial infarction, as well as attenuation of sympathetically mediated coronary vasoconstriction and improvement in coronary blood fl ow to areas at risk.
Which of the following is FALSE for the effects of neuraxial block on thermoregulation? A. Spinal anesthesia increases temperature threshold for sweating. B. Spinal anesthesia decreases temperature threshold for vasoconstriction. C. Spinal anesthesia decreases temperature threshold for shivering. D. Intravenous administration of lidocaine, with equivalent plasma levels; alters thresholds for vasoconstriction and shivering similar to epidural administration of lidocaine. E. The intensity of shivering is decreased by neuraxial anesthesia.
. ANSWER: D Both spinal and epidural anesthesia increase the sweating threshold and decrease the threshold for vasoconstriction and shivering. This is unrelated to plasma levels of local anesthetics, as both spinal anesthesia and epidural anesthesia produce the same effect, and administration of intravenous lidocaine equivalent to plasma levels obtained from an epidural infusion does not produce the same effect. Epidural anesthesia also decreases the maximum intensity of shivering as well as the gain of shivering as the body temperature decreases.
Which of the following is NOT a side effect of Dextran 40? A . Anaphylactoid reaction B . Interference with blood cross-matching C . Renal impairment D. Coagulopathy E. Hyperglycemia
. ANSWER: E Dextran has multiple side effects, including anaphylaxis, renal failure, coagulopathy, and interference in crossmatching blood. Dextran-induced anaphylactoid reactions (DIARs) occur in 1% of patients when patients have IgG antibodies that bind to dextran, causing a type III immunecomplex-meditated anaphylactoid reaction. These reactions can be significantly reduced by pretreating with 20 mL of Dextran 1, a hapten that binds to the patient's dextranreactive antibodies. Dextrans can coat the RBC membranes of the recipient, making blood cross-matching less reliable. Renal failure from dextran is hypothesized to be from accumulation of dextran molecules in the renal tubules. Dextran administration can lead to a coagulopathy with decreased platelet-endothelial adhesiveness, decreased factor VIII, and increased fibrinolysis. Hyperglycemia is not commonly seen despite its sugar backbone.
A 30-year-old man is in the preoperative holding area with a heart rate of 70 beats per minute and an estimated stroke volume of 70 mL. He is breathing 10 times per minute with a tidal volume of 500 mL and an estimated dead space of 100 mL. What is this patient's ventilation/ perfusion ratio? A. 0.5 B. 0.8 C. 1.0 D. 1.2 E. 1.5
.ANSWER: B The ventilation/perfusion (V/Q) ratio can be quantified for the entire lung given some knowledge of the patient's alveolar ventilation and cardiac output. Alveolar ventilation can be calculated by subtracting the dead space volume from the tidal volume and multiplying this difference by the respiratory rate. The cardiac output can be calculated by multiplying the stroke volume by the heart rate. In this example, alveolar ventilation is 4 L/min and cardiac output is 4.9 L/min, giving a V/Q ratio of 0.8.
For an acute respiratory acidosis an increase in Pacó of 20 mm Hg will result in a decrease in pH of A. 0.04 units B. 0.08 units C. 0.12 units D. 0.16 units E. 0.24 units
.ANSWER: D For a purely acute respiratory acidosis, the pH will change 0.08 units for every 10-mm Hg change in the Pacó . For a purely chronic respiratory acidosis, the pH will change 0.03 units for every 10-mm Hg change in the Pacó . For respiratory disorders that are a combination of acute and chronic, then the pH response will be between 0.03 units and 0.08 units for every 10-mm Hg change in the Pacó
Prior to administering general anesthesia to a patient, the anesthesiologist checks for leaks in the anesthesia machine by closing the adjustable pressure-limiting (pop-off) valve, occluding the patient end of the breathing circuit, and filling the system via the Ó flush valve until the reservoir bag is full and there is a pressure within the circuit of approximately 15 to 20 cm H20. The anesthesia machine contains an outlet check valve at the common gas outlet. The Ó flow is then slowly decreased until the pressure no longer rises. This technique will identify gross leaks in which of the following components of the anesthesia machine?(Choose all that apply) 1. Unidirectional expiratory valve 2. Unidirectional inspiratory valve 3. CÓ absorber 4. Vaporizer
1,2,3 The technique described in this question will detect gross leaks in components of the anesthesia machine located "downstream" from the rotameters. These components include gaskets, vaporizers, Thorpe tubes, and the patient breathing circuit. However, in anesthesia machines that have an outlet check valve, the integrity of the low-pressure components of the machine (i.e., vaporizer, rotameter) cannot be assessed using this technique
True statement(s) concerning the metabolism of local anesthetics include which of the following? (Choose all that apply) 1. Plasma clearance of ester-type local anesthetics is decreased in patients who are homozygous for atypical pseudocholinesterase 2. Plasma clearance of ester-type local anesthetics is decreased in patients with severe cirrhotic liver disease 3. Plasma clearance of amide-type local anesthetics is decreased in patients with severe cirrhotic liver disease 4. Plasma clearance of amide-type local anesthetics is decreased in patients with severe renal insufficiency.
1,2,3 Ester-type local anesthetics are hydrolyzed in plasma by pseudocholinesterase, which is produced by the liver. Thus, patients with atypical pseudocholinesterase or severe liver disease will metabolize these drugs more slowly than will normal patients. Renal excretion plays only a minor role in the elimination of amide-type local anesthetics, accounting for less than 1 % to 6% of the dose administered to the patient. Plasma clearance of ester-type local anesthetics may be decreased in patients with impaired hepatic function because the synthesis of pseudocholinesterase by the liver is reduced.
Advantages of the Bain anesthesia breathing circuit include: (Choose all that apply) 1. Improved humidification of the fresh gas inflow as a result of partial re-breathing 2. Ease of scavenging waste anesthetic gases from the overflow valve 3. Rewarming of the fresh gas inflow by the surrounding exhaled gases 4. Ease of detecting kinking of the inner tube
1,2,3 The Bain anesthesia breathing circuit is a coaxial version of a Mapleson D breathing circuit. The fresh gas inflow enters through a tube located within the corrugated expiratory limb of the circuit and an adjustable pressure-relief valve is located near the reservoir bag. Advantages of this design include improved humidification of the fresh gas inflow as a result of partial rebreathing, ease of scavenging waste anesthetic gases from the overflow valve, and warming of the fresh gas inflow by the surrounding exhaled gases. Unfortunately, this design can lead to serious complications. Unrecognized disconnection or kinking of this tube within the expiratory limb of the circuit may lead to hypoxia orrebreathing of exhaled gases.
True statements concerning the arterial pressure waveform generated in the radial artery compared with that generated in the aortic root include which of the following? (Choose all that apply) 1. The systolic pressure is higher 2. The pulse pressure is greater 3. The diastolic pressure is lower 4. The mean arterial pressure is higher
1,2,3 The arterial pulse is caused by a wave of vascular distention that results from the combined effects of the forward-propagating pressure wave (caused by the impact of the stroke volume of the heart into a closed system) and its reflectance back toward the heart from various parts of the vasculature. The arterial pulse wave is not due to the passage of blood itself. The characteristics of the arterial pulse wave change as it moves peripherally. In the peripheral vasculature, the arterial pulse wave has a higher systolic pressure, a lower diastolic pressure, a greater pulse pressure (i.e., the difference between the systolic and diastolic pressures), and a lower mean arterial pressure than in the aorta.
Which of the following mechanical ventilator parameters can influence the tidal volume delivered to patients? (Choose all that apply) 1. Ventilator rate 2. Fresh gas flow 3. l:E ratio 4. PEEP
1,2,3 During the inspiratory phase of the mechanical ventilator cycle, the ventilator pressure-relief valve is closed so that gas from the ventilator bellows and the fresh gas flow entering the circuit from the anesthesia machine are delivered to the patient. Thus, the fresh gas flow will influence the actual VT delivered to the patient. Because the ventilator rate and lIE ratio determine the time during which the ventilator is in the inspiratory phase, these variables will also influence the actual VT. Accordingly, the magnitude of the effect these variables will have on the actual VT delivered to the patient is inversely related to the total pulmonary compliance of the patient relative to that of the anesthesia breathing circuit components
True statements concerning soda lime granules include which of the following? (Choose all that apply) 1. A specific water content is required for optimal activity 2. The hardness of the granules is caused by the addition of silica. 3. The reaction of CÓ with the granules produces heat 4. The granules consist primarily of sodium and potassium hydroxide
1,2,3 In semiclosed or closed anesthesia breathing circuits, CÓ is eliminated by chemical neutralization. This process can be accomplished by mixing exhaled gases with soda lime or Baralyme. Soda lime granules consist primarily of calcium hydroxide. The hardness of these granules is due to the addition of silica. This hardness decreases the amount of dust, which if present can be carried throughout the breathing circuit to the patient, causing chemical injury to the lungs. The reaction of CÓ with calcium hydroxide is exothermic and requires a specific water content to assure optimal activity.
Which of the following conditions is associated with decreased clearance of ester-type local anesthetics? 1. Cirrhotic liver disease 2. Pregnancy 3. Renal insufficiency 4. Severe chronic obstructive pulmonary disease.
1,2,3 Pregnancy is associated with decreased pseudocholinesterase activity; however, this reduction in activity is minimal such that the rate of hydrolysis of ester-type local anesthetics is sufficient to limit significant placental transfer to the fetus. Severe liver disease is associated with a decreased concentration of pseudocholinesterase. Likewise, uremic patients have decreased serum levels of pseudocholinesterase, which may interfere with the metabolism of ester local anesthetics. Pulmonary disease does not affect the clearance of local anesthetics, provided blood flow to the liver is not lowered by hypoxia.
Which of the following drugs will decrease the plasma clearance of amide-type local anesthetics? (Choose all that apply). 1. Propranolol 2. Cimetidine 3. Halothane 4. Phenytoin
1,2,3 Volatile anesthetics, sympathomimetics, BETA-adrenergic receptor antagonists, and the H2-receptor antagonist cimetidine reduce hepatic blood flow, thereby reducing plasma clearance of amidetype local anesthetics. There is also evidence that propranolol directly inhibits mixed-function oxidase activity of hepatocytes. Phenytoin increases clearance of lidocaine by enzyme induction
True statements concerning the structure and function of the Bain anesthesia breathing circuit include which of the following? (Choose all that apply) 1. The fresh gas inflow is located near the patient 2. The overflow valve is located near the reservoir bag 3. The amount of rebreathing depends on the fresh-gas inflow rate 4. Can be used efficiently during controlled ventilation
1,2,3,4 The Bain anesthesia breathing circuit is a coaxial version of a Mapleson D breathing circuit. The fresh gas inflow is located near the patient and an adjustable pressure-relief valve is located near the reservoir bag. This design allows for efficient use during both spontaneous and controlled ventilation. Fresh gas flows of 200 to 300 mLlkglmin are necessary to prevent rebreathing of CÓ when the Bain breathing circuit is used during spontaneous ventilation. Fresh gas flows of 70 mLlkglmin are required when the Bain breathing circuit is used during controlled ventilation
Which of the following affect the efficiency of CÓ neutralization by CÓ absorption canisters?(Choose all that apply) 1. Channeling 2. Tidal volume 3. Size of the granules 4. pH of the fluid inside the canister
1,2,3,4 The optimal CÓ absorptive condition of soda lime or Baralyme canisters exists when the patient's VT is accommodated entirely within the void space of the canister. This optimal condition depends on the size of the granules and the presence or absence of channeling within the canister. Channeling is the passage of exhaled gases through low-resistance pathways within the canister, such that the majority of the granules are bypassed. Low pH is associated with depletion of CÓ neutralizing capacity.
Mass spectrometry readings of nitrogen are taken in a patient who is paralyzed, intubated, and on a ventilator. The inspired nitrogen concentration is 0 and expired nitrogen is 3.2%. Possible explanations for these would include:(Choose all that apply) 1. Nitrogen washout 2. A leak in the CÓ absorber 3. Air embolism 4. A deflated endotracheal cuff
1,3 Monitoring end-expired and inspired nitrogen by mass spectrometer can be a useful tool during anesthesia. For example, monitoring of end-tidal nitrogen during preoxygenation before rapid sequence induction of anesthesia will ensure adequate denitrogenation of the patient. Additionally, an increase in end-tidal nitrogen is a sensitive means for detecting air entering the cardiovascular system, such as venous air embolism via open veins during pelvic, thoracic, or intracranial surgery. An equipment fault causing an air leak into the anesthetic breathing system or into the mass spectrometry sampling system would be detected by an increase in inspired nitrogen.
Duration of action of local anesthetics may be increased by (Choose all that apply). 1. Adding vasoconstrictors 2. Adding bicarbonate 3. Increasing the dose 4. Use of carbonated solutions
1,3 Addition of CÓ or HC03- to local anesthetic solutions hastens the onset of the anesthetic block but does not increase its duration. Vasoconstrictors decrease absorption (and metabolism) of local anesthetics. A larger dose results in longer anesthetic duration, as well as denser blockade .
Drugs that will decrease the plasma clearance of ester-type local anesthetics include:(Choose all that apply). 1. Echothiophate 2. N20 3. Neostigmine 4. Phenytoin
1,3 Ester-type local anesthetics are broken down partly in the blood by pseudocholinesterase and red cell esterase and partly in the liver. Anticholinesterase drugs, such as echothiophate, neostigmine, pyridostigmine, and edrophonium, inhibit pseudocholinesterase and thus slow the plasma clearance of ester-type local anesthetics. Phenytoin is an enzyme inducer that may hasten the metabolism of amide-type local anesthetics, such as lidocaine but would have little, if any, effect on ester-type local anesthetics and would certainly not impede their plasma clearance.
Which of the following factors cause overdamping of direct arterial pressure waveforms?(Choose all that apply) 1. Long length of tubing 2. Low viscosity of fluid in tubing 3. Small radius of tubing 4. Low compliance of tubing
1,3 The mechanical characteristics of transducer systems can be understood by the description of two parameters: natural frequency and damping coefficient. The natural frequency of a transducer system is the frequency at which the system will resonate. Any physiologic frequency occurring near the natural frequency of the transducer system is amplified. For this reason, the natural frequency of standard transducer systems used to measure arterial blood pressure is greater than that which exists in a blood pressure signal (which is approximately 20 Hz). The damping coefficient represents the tendency of the transducer system to extinguish oscillations through viscous and frictional forces. The damping coefficient is dependent on several mechanical characteristics of the transducer system and is mathematically expressed as follows.
Factor(s) that antagonize local anesthetics include 1. Tissue acidosis 2. Presence of myelin 3. Increasing fiber diameter 4. Rapid firing rate
1,3 The presence of myelin and a rapid neuronal firing rate actually enhance the ability of local anesthetics to block the neuron. Local anesthetics gain access to receptors when the sodium channels are open, as occurs during an action potential. Larger-diameter fibers are more difficult to block than small-diameter fibers. Tissue acidosis results in formation of the ionized form of the local anesthetics. This form does not readily transverse the lipophilic cell membrane
A 22-year-old college student involved in a motor vehicle accident sustains numerous injuries, including a closed head injury. He is unconscious and unresponsive to all external stimuli. Disadvantages of using urea compared with mannitol to reduce ICP include:(Choose all of the questions that are correct). 1. A higher incidence of rebound intracranial hypertension with urea 2. A higher incidence of venous thrombosis with urea 3. An increased ability of urea to penetrate an intact blood-brain barrier 4. A higher incidence of myocardial depression with urea.
1. A higher incidence of rebound intracranial hypertension with urea 2. A higher incidence of venous thrombosis with urea 3. An increased ability of urea to penetrate an intact blood-brain barrier. Hyperosmotic drugs, such as mannitol and urea, and loop diuretics, such as furosemide, are effective in reducing ICP because intracellular water is a significant component of the intracranial contents. The maximum reduction in ICP typically occurs within 15 to 60 minutes after administration of these agents. Mannitol should be administered intravenously in doses of 0.25 to 1.0 g/kg over 15 to 30 minutes. Doses of mannitol greater than or equal to 1.0 g/kg do not further increase the magnitude of ICP reduction. Urea should be administered intravenously in doses of 1.0 to 1.5 g/kg over 15 to 30 minutes. Rebound intracranial hypertension occurs more frequently after administration of urea compared with mannitol. This observation reflects the ability of urea molecules to penetrate the blood-brain barrier, which reduces the osmotic gradient and increases brain water. Another disadvantage of urea (compared with mannitol) is a high incidence of venous thrombosis should extravasation of the urea occur. Because osmotic diuretics can initially increase intravascular fluid volume, these agents should be administered ctu'efu lly in patients with limited cardiac reserve. The incidence of venous thrombosis after administration of mannitol is low. Neither mannitol nor urea causes myocardial depression.
What is the blood to gas partition coeffcient of halothane? (A) 0.47 (B) 0.65 (C) 1.4 (D) 2.4
(D) 2.4 The blood to gas partition coeffcient of nitrous oxide is 0.47; sevoflurane is 0.65; and iso urane is 1.4.
Choose all items that correctly match anatomic structures with their level of termination in adults. (Choose all that apply). 1. Spinal cord, LI-L2 2. Preganglionic sympathetic nerves, L2 3. Spinal canal, sacral hiatus 4. Dural sac, S4
1,2,3 In adults the spinal cord ends at LI-L2. The sympathetic nerve fiber originates in the intermediolateral grey column of the TI-L2 spinal segments. The spinal canal originates at the foramen magnum and terminates at the sacral hiatus. The dural sac terminates at S2 in adults.
dentify the concept that most closely correlates with local anesthetic potency a. pKa b. lipid solubility c. addition of epi d. protein binding
b. lipid solubility
Rank the following nondepolarizing NMBA in terms of potency (1-most potent, 4-least) Cisatracurium Rocuronium Pancuronium Atracurium
1= Cisatracurium 2= Pancuronium 3= Atracurium 4= Rocuronium
What is the maximum dose of EMLA cream for a 9 month old infant who weighs 8kg?
2g EMLA cream contains a 50/50 mixtures of lidocaine and prilocaine
Which of the following materials will not ignite during laser surgery of the airway?(Choose all that apply) 1. Rubber 2. Silicone 3 Polyvinyl chloride (PVC) 4. Metal
4, Any endotracheal tube not constructed of metal has the potential to ignite in an 02-enriched environment. PVC tubes are ignited most easily. Silicone endotracheal tubes are more difficult to ignite than PVC tubes
Match each type of peripheral nerve with its function. a. A alpha............................ 1. fast pain b. A delta............................. 2. preganglionic SNS c. C ---------------------3. Motor d. B ---------------------4. slow pain
A alpha= motor A delta= fast pain B= preganglionic SNS C= slow pain
An 82-year-old female arrives to the OR for open reduction of a left intratrochanteric fracture. Significant past medical history includes hypertension, moderate aortic stenosis and dementia. The most appropriate anesthetic technique for this patient is: A-opioid-based general anesthesia B-spinal anesthesia C-volatile-agent-based general anesthesia D-epidural anesthesia
A-opioid-based general anesthesia In patients with mild to moderate aortic stenosis, a primarily opioid-based technique results in minimal cardiac depression, less tachycardia and suppression of the sympathetic response to surgical stimulation. These are all desired effects as HTN and tachycardia may precipitate ischemia in these patients. Spinal or epidural anesthesia as well as a volatile-agent-based anesthesia can cause a fall in afterload with resulting severe hypotension.
Signs of air embolism in a patient include all, except A. Hypertension B. Heart murmur C. Arrhythmia D. Decreased EtCÓ
A. Clinical signs of venous air embolism include a decrease in end-tidal CÓ, a decrease in arterial oxygen saturation, sudden hypotension, mill wheel murmur, and even sudden circulatory arrest. Presence of a patent foramen ovale, which has an incidence of 20% in adults, can lead to paradoxical air embolism, with the potential of causing coronary ischemia or a stroke.
Which of the following statements is true regarding fluid loss? A. Substantial evaporative losses can be associated with large wounds and are directly proportionate to the surface area exposed B. Internal redistribution of fluids, "third spacing," cannot cause massive fluid shifts C. Traumatized, inflamed, or infected tissues can only sequester minimal amounts of fluid in the interstitial space D. Cellular dysfunction as a result of hypoxia usually produces a decrease in intracellular fluid volume.
A. Substantial evaporative losses can be associated with large wounds and are directly proportionate to the surface area exposed. Third spacing can cause massive fluid shifts, and traumatized, inflamed, or infected tissue can sequester large amounts of fluid. Cellular dysfunction as a result of hypoxia usually produces an increase in intracellular fluid volume
In a conventional crossmatch: A. Donor cells are mixed with recipient serum B. Recipient cells are mixed with donor serum C. Donor serum is tested against red cells of known antigenic composition D. None of the above.
A. A crossmatch mimics a transfusion, where donor cells are mixed with the recipient's serum. This has three purposes: (1) confirms ABO/Rh typing, (2) detects recipient antibodies to other blood group systems, and (3) detects antibodies in low titers or those that do not agglutinate easily. Choice C describes an antibody screen
A 24-year-old female status postrecent living-related renal transplant requires chronic immunosuppression with cyclosporine and steroids to combat organ rejection. She now presents for right-knee arthroscopic anterior cruciate ligament repair and mentions significant history of postoperative nausea and vomiting (PONV). The most appropriate next step in planning her anesthetic management is A. Proceed with total IV anesthesia (TIVA), avoiding inhaled anesthetics B. Avoid regional anesthesia C. Liberally infuse intravenous fluids D. Use metoclopramide to decrease gastric secretions
A. Transplant recipients are always under various regimens of immunosuppression to prevent organ rejection. Clinically significant reductions in serum levels of these medications can be caused by dilution with massive fluid resuscitation perioperatively, as well as with cardiopulmonary bypass. Many immunosuppressants are metabolized in the liver via the cytochrome P450 system such that drugs administered during anesthesia (or perioperatively) may affect blood levels including increased concentrations with cimetidine and metoclopramide and decreased levels with octreotide. Regional anesthesia and/or TIVA are reasonable options to minimize PONV in this patient.
A standing or ascending bellow is preferred for anesthesia ventilators, as disconnection is indicated by: A. Collapse B. Filling by gravity C. Disconnection alarm D. Stoppage of flowmeter gas
A. An ascending bellow collapses when disconnection occurs. A descending bellow, however, continues to fill by gravity when disconnection occurs. Therefore, ascending bellows are preferred for anesthesia ventilators.
Since fresh gas flow equal to minute ventilation is sufficient to prevent rebreathing, which of the following Mapleson circuit breathing/ventilation systems is the most efficient for spontaneous ventilation of the patient? A. Mapleson A B. Mapleson B C. Mapleson C D. Mapleson D
A. During spontaneous ventilation/breathing of the patient, the Mapleson circuit providing for the most efficacy ranges from A > D > C > B (in the order of decreasing efficiency).
A pulmonary artery catheter is placed to help guide management of hypotension. Cardiac output is found to be markedly decreased with low central venous, pulmonary artery, and pulmonary artery occlusion pressures. Systemic vascular resistance is moderately elevated. Of the options listed below, the most beneficial intervention at this time would be to A. Administer volume B. Begin diuresis C. Start an infusion of milrinone D. Start an infusion of epinephrine
A. In the clinical scenario, low central venous, pulmonary artery, and pulmonary artery occlusion pressures support the diagnosis of hypovolemia. Increasing intravascular volume would be the most beneficial intervention at this time.
A 65-year-old patient is noted to have excessive bleeding during a colectomy with an activated clotting time (ACT) of 200 seconds. The most unlikely reason for this oozing is: A. Undiagnosed factor VII deficiency B. Prior administration of heparin 5,000 U subcutaneously C. Preoperative ingestion of aspirin and ibuprofen D. Dilutional thrombocytopenia
A. The ACT enables one to monitor the anticoagulant effect of unfractionated heparin. ACT prolongation can also indicate coagulation-factor deficiency, severe thrombocytopenia, or severe platelet dysfunction. The ACT is sensitive to a deficiency or dysfunction of all the clotting factors (except factor VII)—indicating problems with the intrinsic or common pathways. Factor level must be less than 5% of normal to prolong the ACT
Detrimental effects of hypothermia include all of the following, except: A. Increasing cerebral oxygen consumption . B. Increasing surgical site infections . C. Impairment of platelet function. D. Increasing the duration of action of muscle relaxants.
A. Uncontrolled hypothermia has many detrimental effects, including increased oxygen utilization through shivering, impaired platelet function and coagulation, delayed wound healing and increasing surgical site infections, as well as potential for serious dysrhythmias. Cerebral oxygen consumption, however, decreases by approximately 7% per degree Celsius decrease in temperature.
Incorrect statement regarding the mechanisms of an Ambu bag is A. It contains a non-rebreathing valve, same as the circle system B. It is capable of delivery of nearly a 100% Ó concentration C. It allows for positive-pressure ventilation D. Patient valve has low resistance to both inspiration and expiration
A. While resuscitation devices such as Ambu bags or bag-mask units have nonrebreathing valves, neither the Mapleson (only has adjustable pressure-limiting valve) nor the circle system (only has unidirectional valves and does allow rebreathing) has this component. Ambu resuscitation bags do allow for positivepressure ventilation as the intake valve closes during bag compression. The patient valve has low resistance, but can become obstructed by exhaled moisture. Ambu bags have a reservoir system to prevent room air entrapment and are able to deliver nearly 100% oxygen.
What does horner syndrome after brachial plexus block indicate? A. A successful block B. High block C. Pneumothorax D. Nerve damage
A. A successful block
Each of the following is associated with acute tubular necrosis, except A. Hyaline casts B. Urine specific gravity <1.010 C. Muddy casts D. Fractional excretion of sodium of 4%
A. Acute tubular necrosis is classified as a "renal" (e.g., not prerenal or postrenal) cause of acute kidney injury. Diagnosis is made by a fractional excretion of sodium >3%, greater than expected urine sodium concentration with low osmolality and presence of muddy casts on urinalysis. A sensitive indicator of tubular function is sodium handling because the ability of an injured tubule to reabsorb sodium is impaired, whereas an intact tubule can maintain this resorptive capacity. If the patient has tubular damage for any reason, the urinary sodium will be greater than expected. Keep in mind that the use of diuretics, however, can complicate the interpretation of these results. Low urine flow, concentrated urine, or an acidic environment can contribute to the formation of hyaline casts, pointing to hypovolemia and prerenal failure (Table 14-3).
Which 2 steps are important in a transtracheal block A. Aspirating until air is pulled into the syringe. B. Penetrating the hypothyroid membrane. C. Penetrating the cricothyroid membrane. D. Inserting the needle into the trachea inferior to the cricoid cartilage.
A. Aspirating until air is pulled into the syringe. C. Penetrating the cricothyroid membrane.
While performing an axillary brachial plexus blockade, the goal is to deposit local anesthetic medications at what location of the brachial plexus and to target which specific nerve structures? A. Level of the branches and targeting the radial, median, and ulnar peripheral nerves B. Level of the trunks and targeting the interscalene, radial, and ulnar peripheral nerves C. Level of the divisions and targeting the supraclavicular, median, and radial peripheral nerves D. Level of the cords and targeting the infraclavicular, ulnar, and radial peripheral nerves.
A. Axillary block is typically performed at the level of the individual peripheral nerve branches of the brachial plexus, specifically the radial, median, and ulnar nerves.
What is the function of cranial nerve 3? A. Both sensory and motor. B. Just motor. C. Just sensory. D. None.
A. Both sensory and motor.
Regarding assessment of surgical blood loss A. Both surgeons and anesthesiologists tend to underestimate blood loss B. Measurement of blood in the surgical suction container is all that is necessary to estimate blood loss C. The use of irrigating solutions does not complicate assessment of blood loss D. A soaked "lap" pad can hold 10 to 15 mL of blood
A. Both surgeons and anesthesiologists tend to underestimate blood loss. Measurement of blood in the surgical suction container is only one component of estimating blood loss. Blood lost in sponges, "lap" pads, and occult bleeding under the drapes must be accounted for. The use of irrigating solutions often complicates the assessment of blood loss. A soaked "lap" pad can hold up to 100 to 150 mL of blood
Knowing the sensory dermatomes of the hand, which nerve root would you want to block if surgery will be performed on the little finger (fifth digit) A. C8 B. C7 C. C6 D. C4
A. C8
Regarding central venous pressure (CVP) monitoring A. Low values of <5 mm Hg may be considered normal in the absence of other signs of hypovolemia B. CVP readings can be interpreted independently of the clinical setting C. CVP monitoring is never indicated in patients with normal cardiac and pulmonary function D. In a patient with right ventricular dysfunction, a CVP of 10 mm Hg should be considered elevated.
A. CVP measurements must be evaluated in context of the clinical setting. Factors such as underlying cardiopulmonary disease, patient position, and anatomy can affect the values. A CVP of <5 mm Hg can be normal in a healthy patient without signs of hypovolemia. For surgical cases during which large fluid shifts are expected, placement of a CVP monitor may be indicated. Patients with compromised right ventricular function generally have high CVPs, and thus, a CVP of 10 mm Hg should be considered normal to low depending on the degree of dysfunction.
You receive a patient from the emergency department with multiple stab wounds to the upper abdomen. The patient is unstable, and needs to emergently come to the operating room with minimal to no time for fluid resuscitation. After placing a central line, you notice loss of the Y descent on the CVP tracing, as well as universally elevated filling pressures. If you were to then do an echocardiogram, you might expect to find which of the following? A. Cardiac tamponade B. Significant tricuspid regurgitation C. Descending thoracic aortic dissection D. AV dissociation
A. Cardiac tamponade It would be highly unlikely to have elevated filling pressures in a bleeding trauma patient who has not yet been resuscitated. Aortic dissections can cause cardiac tamponade, but only if they involve the aortic root and then extend into the pericardium
Therapy for cerebral vasospasm includes A. Hypertension, hypervolemia, hemodilution B. Normotension, euvolemia, hypocarbia C. Hypotension, hypovolemia, hypocarbia D. Hypertension, hypervolemia, hypocarbia
A. Cerebral vasospasm occurs in about one-third of patients surviving the initial aneurysmal rupture, and carries a high degree of morbidity and mortality. The degree of vasospasm depends on the degree of initial subarachnoid hemorrhage. Vasospasm usually develops 3 to 14 days postsubarachnoid hemorrhage results in narrowing of cerebral blood vessels and decreased blood flow distally. This may lead to an ischemic deficit and cerebral infarction, if left untreated. Therapies for cerebral vasospasm include "triple-H therapy" (hypertension/hypervolemia/hemodilution), balloon angioplasty, and intra-arterial nicardipine and other vasodilators.<CT>
Which 2 landmarks are used to locate the sacral hiatus? A. Coccyx B. Sacral Cornua C. Iliac crest. D. Ischial Spine
A. Coccyx B. Sacral Cornua
All of the following are contraindications of electroconvulsive therapy (ECT), except : A. Pacemaker B. Recent stroke C. Raised intracranial pressure D. Severe osteoporosis
A. Contraindications to ECT include recent myocardial infarction (<3 months), a recent stroke (<1 month), an intracranial mass and raised intracranial pressure, angina, poorly controlled congestive heart failure, significant pulmonary disease, bone fractures, severe osteoporosis, pregnancy, glaucoma, and retinal detachment
A 28-year-old male is being treated in the ICU for raised intracranial pressure (ICP). All the following measures can aid in decreasing ICP quickly, except A. Corticosteroids B. Hyperventilation to PaCÓ of 30 mm Hg C. Mannitol D. Head elevation to 30 degrees
A. Definitive treatment of intracranial hypertension is ideally directed at the underlying cause. Treatment modalities include fluid restriction, head elevation, osmotic agents and loop diuretics, moderate hyperventilation (up to 24-36 hours), avoidance of hypotension, hypoxia and hypercarbia, and corticosteroids. The latter is used to decrease cerebral edema in patients with known intracranial tumors, and take a few hours to take effect.
Four days after a left total hip arthroplasty, an obese 62-year-old woman complains of severe back pain in the region where the epidural was placed. Over the ensuing 48 hours, the back pain gradually worsens and a severe aching pain that radiates down the left leg to the knee develops. The most likely diagnosis is A. Epidural abscess B. Epidural hematoma C. Anterior spinal artery syndrome D. Arachnoiditis E. Meralgia paresthetica
A. Epidural abscess Development of an epidural abscess is fortunately an exceedingly rare complication of spinal and epidural anesthesia. When it does occur, prompt recognition and treatment are essential if permanent sequelae are to be avoided. Symptoms from an epidural abscess may not become apparent until several days after placement of the block. The usual symptoms include severe back pain, sensory disturbances, and motor weakness. Unlike an epidural hematoma in which severe back pain is the key feature, patients with epidural abscesses will complain of radicular pain approximately 3 days after development of the back pain. Anterior spinal artery syndrome is characterized predominantly by motor weakness or paralysis of the lower extremities. Meralgia paresthetica is related to entrapment of the lateral femoral cutaneous nerve as it courses below the inguinal ligament and is associated with burning pain over the lateral aspect of the thigh. It is not a complication of epidural anesthesia.
You are consulted on an ASA IV patient for a right-ankle surgery. The patient has a known history of difficult intubation and status post-spinal fusion surgery. The surgeon is requesting for a peripheral nerve block that will provide for surgical anesthesia. Which of the following nerves will need to be blocked in order to provide for complete anesthesia during performance of foot and ankle surgery? A. Both sciatic and femoral nerve blockade B. Sciatic nerve block alone C. Femoral nerve block alone D. Sciatic, femoral, and obturator nerve blocks
A. For complete surgical anesthesia of the foot and ankle, both sciatic and femoral/saphenous nerves need to be anesthetized/blocked. The obturator nerve does not provide sensory or motor nerve distribution to foot or ankle.
A 65-year-old male is undergoing surgery for medulloblastoma in the posterior fossa of brain. Approximately 1 hour into surgery you notice arrhythmias on the monitors. The next step will be : A. Inform the surgeon B. Give β-blockers C. Administer lidocaine D. Give 100% oxygen
A. For posterior fossa tumor resection, the patient is frequently placed in the sitting or prone position. Monitoring of the patient includes arterial blood pressure line, a central venous catheter (for access, pressure monitoring, aspiration of any air —if required), and a precordial Doppler to detect intracardiac air (venous air embolism). Operations on posterior fossa tumors can injure vital brain-stem respiratory and circulatory nuclei, resulting in hemodynamic fluctuations or depression of ventilation. The surgeon should be informed at the first sign of cardiac arrhythmias.
A patient with spinal injury, sustained 3 hours ago, comes to the OR for exploratory laparotomy. Anesthetic management of the patient includes which of the following? A. Rapid-sequence induction with succinylcholine B. Hypothermia for better neurologic outcome C. Managing autonomic hyperreflexia D. Avoiding corticosteroids
A. In the early management of acute spinal injury patients, particular emphasis should be placed on preventing further spinal damage, which may occur during patient movement, airway manipulation, and positioning. High-dose corticosteroids are often administered to help improve neurological outcome. The head and neck should be stabilized using manual inline stabilization, and awake fiberoptic intubation should be considered in high cervical injuries. Patients with high cord transections may have impaired airway reflexes, hypotension, and bradycardia and may be prone to hypothermia in view of generalized vasodilation. Succinylcholine can be used safely in first 24 hours following spinal injury.
The most important factor governing cerebral blood flow (CBF) is A. Cerebral metabolic oxygen demand B. PaCÓ C. pH D. Cerebral perfusion pressure
A. Increased metabolic activity leads to an increase in CBF. Regional CBF parallels metabolic activity and can vary from 10 to 300 mL/100 g/min. For example, motor activity of a limb is associated with a rapid increase in regional blood flow of the corresponding motor cortex.
The only inhalational anesthetic that can cause an isoelectric EEG among the following is : A. Isoflurane B. Halothane C. Enflurane D. Nitrous oxide
A. Isoflurane can produce an isoelectric EEG at 2 to 2.5 MAC, while enflurane typically produces a spike and wave pattern at 2 to 3 MAC. Seizure activity may be seen on EEG with 3% enflurane in a hypocapnic patient. Halothane causes slowing of EEG activity with increasing concentration until 4 MAC, after which it produces uniform activity. Increasing sevoflurane concentration from 2 to 5 MAC changes the cortical EEG pattern from a high-amplitude slow wave to burst suppression to an isoelectric EEG interspersed with spikes
In the "three in one" block, which of the following are the nerves that can be blocked? A. Lateral femoral cutaneous B. Femoral C. Popliteal saphenous D. Obturator E. Posterior femoral cutaneous
A. Lateral femoral cutaneous B. Femoral D. Obturator
A patient presents for preoperative evaluation for upcoming surgery. He has a history of liver transplantation 2 years ago, otherwise feeling well. Which of the following is most likely to be present during preoperative evaluation? A. Elevated serum creatinine concentration B. Hypoalbuminemia C. Prolonged partial thromboplastin time D. Hypocalcemia
A. Long-standing insufficient liver function is believed to cause changes in the circulation that changes vessel tone and blood flow in the kidneys. The likely presence of renal insufficiency is a consequence of these changes in blood flow, rather than direct damage to the kidney itself.
The drug of choice for treating nausea and vomiting in a patient with parkinsonism would be: A. Ondansetron B. Promethazine C. Droperidol D. Metoclopramide
A. Parkinson disease is a movement disorder that affects individuals 50 to 70 years of age. It is caused by progressive loss of dopamine in the nigrostriatum. Patients have bradykinesia, postural instability, rigidity, facial masking, and a resting pillrolling tremor. Antidopaminergic activity associated with butyrophenones, phenothiazines, and metoclopramide can worsen symptoms and thus these should be avoided.
Contraindications to safely perform peripheral regional anesthesia include all of the following, except A. Patients who may not provide absolute cooperation during nerve block placement (mental retardation) without administration of sedation B. Patient refusal C. Severe coagulopathy while anticipating a deep nerve plexus blockade D. Evidence of infection at injection site
A. Patient refusal is an absolute contraindication following informed consent. Evidence of anticipated injection-site infection and severe coagulopathy are considered relative contraindications, and risk-to-benefit analysis needs to be carefully considered. Non-cooperative patients can often pose an increased risk to patient/operator safety, but it is not an absolute contraindication to performing regional anesthesia.
While performing the popliteal approach for a sciatic nerve block under ultrasound guidance, you are able to identify the popliteal artery adjacent to two hyperechoic nerve structures that appear to become one nerve structure upon proximal movement of the ultrasound probe placed within the popliteal fossa. The correct identity of the two nerve branches is A. The nerve on the lateral side is the common peroneal nerve, and the nerve on the medial side is the tibial nerve (combined nerve is the sciatic nerve) B. The nerve on the lateral side is the sciatic nerve, and nerve on the medial side is the deep peroneal nerve (combined nerve is the femoral nerve) C. The nerve on the lateral side is the common tibial nerve, and nerve on the medial is the superficial peroneal nerve (combined nerve is the sciatic nerve) D. The nerve on the lateral side is the common posterior tibial nerve, and the nerve on the medial side is the superficial peroneal nerve (combined nerve is the femoral nerve)
A. Popliteal approach to the sciatic nerve block is typically performed at the site of bifurcation of the tibial (medial position) and common peroneal (lateral position) nerves. The sciatic nerve is most optimally blocked with local anesthetic at the union (bifurcation) of these two nerves that frequently become one nerve structure approximately 7 to 10 cm proximal to the popliteal crease.
The primary mechanism by which the action of tetracaine is terminated when used for spinal anesthesia is A. Systemic absorption B. Uptake into neurons C. Hydrolysis by pseudocholinesterase D. Hydrolysis by nonspecific esterases E. Spontaneous degradation at 37°C
A. Systemic absorption Ester local anesthetics are hydrolyzed by cholinesterase enzymes that are present mainly in plasma and in a smaller amount in liver. Because there is no cholinesterase enzymes present in cerebrospinal fluid (CSF), the anesthetic effect of tetracaine will persist until it is absorbed into systemic circulation. The rate of hydrolysis varies, with chloroprocaine being fastest, procaine intermediate, and tetracaine the slowest. Toxicity is inversely related to the rate of hydrolysis; tetracaine is, therefore, the most toxic.
Systolic blood pressures are generally higher and diastolic blood pressures are generally lower in which of the following conditions? A. The further you are from the heart when using a direct arterial measurement B. The closer you are to the heart when using a direct arterial measurement C. When using an automated noninvasive blood pressure cuff compared to a direct arterial measurement D. When recording from an over dampened arterial tracing
A. Systolic blood pressures are generally higher and diastolic blood pressures are generally lower the further you are from the heart when using direct invasive arterial measurement. For example, when comparing a dorsalis pedis arterial measurement to a femoral arterial measurement, the dorsalis pedis will record higher systolic and lower diastolic pressures compared to the femoral line. However, the mean arterial pressures will be approximately the same. A noninvasive automated blood pressure cuff will tend to correlate with systolic arterial blood pressures, but the diastolic pressure will be approximately 10 mm Hg lower when measured via the direct invasive arterial monitor. An over dampened arterial line tracing will tend to reduce systolic pressures and increase diastolic pressures.
Electrical nerve stimulation of which of the following nerves will produce quadriceps muscle contraction? A. Femoral nerve B. Sciatic nerve C. Lateral femoral cutaneous nerve D. Obturator nerve
A. The femoral nerve provides motor supply to the quadriceps muscles and sensory supply to portion of the medial thigh. The femoral nerve does not have any motor components below the knee (only a sensory branch, saphenous nerve, below the knee).
During placement of an ultrasound-guided and nerve stimulator-assisted axillary nerve block, your needle tip is imaged superiorly to the axillary artery. You also see pronation of the patient's forearm. The needle tip is in closest proximity to which of the following branches of the brachial plexus? A. Median nerve B. Axillary nerve C. Musculocutaneous nerve D. Interscalene nerve
A. The median nerve is most frequently positioned superior to the axillary artery (with some anatomical variations). Stimulation of the median nerve will cause muscle stimulation, creating wrist flexion, thumb opposition, and forearm pronation.
You perform a right-side T3-T5 paravertebral blockade for a patient who is to undergo a right mastectomy with axillary lymph node dissection. Medical history of the patient includes alcohol abuse and panic attacks. After the surgery in the post- anesthesia care unit, the patient complains of a new-onset right-arm paresthesia. Vital signs remain stable along with strong and equal upper extremity bilateral pulses. The most likely diagnosis is A. Surgery-related brachial plexus nerve injury and/or positional injury B. The patient is experiencing withdrawal from alcohol C. Side effects/complications of the paravertebral block on the brachial plexus D. Patient is having a panic attack
A. The most likely cause is secondary to axillary lymph node dissection-related brachial plexus injury. The level of paravertebral blocks was at T3-T5; therefore, the brachial plexus should not be affected (C4-T1) by the paravertebral-injected local anesthetic.
For patients with COPD, preoperative management should include which of the following (Choose 2) a. treating infections b. serial arterial blood gases c. mechanical ventilation d. relieving brochospasm
A;D
In order to perform surgery on the knee, which of the following nerves should be blocked? (Choose all that apply). 1. Femoral nerve 2. Sciatic nerve 3. Lateral femoral cutaneous nerve 4. Obturator nerve
ALL, The knee is innervated anteriorly by the femoral nerve, medially by the obturator nerve, posteriorly by the sciatic, and laterally by the common peroneal and the lateral femoral cutaneous nerves. All of these must be blocked for operative procedures.
Your patient's hemodynamic profile is as follows: HR = 100 beats/minute, cardiac output (CO) = 5.0 L/min, end-diastolic volume (EDV)= 100 mL. Calculate the ejection fraction and write the answer in the box below:
Answer = 50% Rationale: First EDV - ESV/EDV = SV Second = HR x CO = Third = CO/HR /EDV = 5000 mL/100/ 100 Forth= STEP 4: Convert to % by multiplying × 100 = 50%
The largest fraction of carbon dioxide in the blood is in the form of : A - carbamino compounds B- Bicarbonate C- Dissolved gas D- Carboxyhemoglobin
B
Which of the following drugs should NOT be administered via an endotracheal tube? A. Lidocaine B. HC03 C. Atropine D. Naloxone E. Epinephrine
B) N.A.V.E.L narcan, atropine, vasopressin, epinepherine, lidocaine
Electrocardiographic changes seen with hypokalemia include: A-peaked T waves B-increasingly prominent U waves C-shortened PR interval with P wave inversion D-decreased QRS amplitude
B-increasingly prominent U waves Electrocardiographic changes seen with hypokalemia include: T wave flattening/inversion ST segment depression increased P wave amplitude prolongation of the P-R interval increasingly prominent U waves
Characteristics of omphalocele include: (Select 2) location lateral to the umbilicus : A-lacks a hernia sac B-results from the failure of midgut migration into the abdomen C-nitrous oxide should be used during the repair to ensure a rapid emergence. D-association with trisomy 21 E-results from abnormal development of the right omphalomesenteric artery.
B-results from the failure of midgut migration into the abdomen. D-association with trisomy 21. Gastroschisis and omphalocele are characterized by defects in the abdominal wall that allow herniation of the viscera. Omphaoceles occur at the base of the umbilicus, have a hernia sac and are commonly associated with other anomalies. In contrast, gastroschisis is usually lateral to the umbilicus, lacks a hernia sac and is usually an isolated finding. Nitrous oxide is best avoided during repair as it may result in bowel distention making closure more difficult.
What is the most likely risk of a digital block? A. Failure of block. B. Nerve injury. C. Prolonged block. D. Ischemic digit.
B. Nerve injury.
The desired level of PaCÓ in a neurosurgical patient is : A. 30 to 35 mm Hg B. 25 to 30 mm Hg C. 20 to 25 mm Hg D. 15 to 25 mm Hg
B. PaCÓ is the most potent physiologic determinant of cerebral blood flow. Maximal reductions in ICP can be achieved by decreasing PaCÓ to 25 to 28 mm Hg, and the reduction in ICP lasts up to 24 to 36 hours.
Immediately before unclamping and reperfusion of the transplanted liver, sodium bicarbonate and calcium chloride are administered intravenously to counteract A. Coagulopathy B. Decreased cardiac output C. Increased systemic vascular resistance D. Hypertension
B. Postreperfusion syndrome is the most common hemodynamic derangement in liver transplantation, manifesting mainly as decreased heart rate, mean arterial pressure, and systemic vascular resistances. Ventricular function, both right and left, has been shown to be normal during reperfusion, in which case the visceral and liver vasodilation that occurs would be the main cause of arterial hypotension. Prophylaxis with atropine prevents bradycardia but not hypotension. Administration of calcium chloride and sodium bicarbonate together with hyperventilation mitigates the symptoms related to the reduced cardiac output
. Which one of the following patients would you choose to administer platelets to? A. A pregnant patient with HELLP syndrome expecting to undergo emergent cesarean delivery, platelet count 100 × 10 9 /L B . A patient with an intracranial hemorrhage on aspirin and clopidogrel requiring decompressive craniectomy, platelet count 200 × 10 9 /L C . A pregnant patient expecting to deliver vaginally without an epidural, platelet count 55 × 10 9 /L D. A patient with thrombotic thrombocytopenic purpura (TTP) requiring dialysis catheter placement for plasmapheresis, platelet count 50 × 10 9 /L E . A patient who is post-cardiopulmonary bypass arriving in the cardiothoracic intensive care unit with an output of 50 cc/h of blood from the chest tube, platelet count 200 × 10 9 /L
B. Bleeding into a closed or noncompliant space such as the brain, eye, and spine demands immediate reversal of anticoagulation. Clopidogrel irreversibly inhibits the P2Y 12 receptor and thus prevents the cross-linking of platelets to fibrin, the final step in the clotting cascade pathway. Aspirin irreversibly inactivates the cyclooxygenase enzyme and thus blocks the formation of thromboxane A 2 in platelets, further decreasing platelet aggregation. While transfused platelets in a patient on these agents may also be inactivated, their transfusion would be appropriate in the scenario given. According to the 2006 ASA Task Force Practice Guidelines for Perioperative Blood Transfusion and Adjuvant Th erapies, "platelet transfusion is rarely indicated if the platelet count is known to be greater than 100 × 10 9/ L and is usually indicated when the count is below 50 × 10 9 /L in the presence of excessive bleeding." Furthermore, procedures with limited anticipated blood loss, including vaginal deliveries, may be performed with platelet counts less than 50 × 10 9 /L. A lthough HELLP syndrome may lead to worsening thrombocytopenia and possible bleeding, transfusion would not be warranted at this time according to the guidelines. Th e transfusion of platelets in disseminated intravascular coagulation (DIC) or other consumptive processes featuring active platelet destruction, such as heparin-induced thrombocytopenia (HIT), TTP, and idiopathic thrombocytopenic purpura (ITP), is generally not indicated unless there is uncontrolled bleeding or the platelet count is less than 20K. Although platelet dysfunction is common aft er cardiopulmonary bypass, there is no clear indication for platelet transfusion if chest tube output does not suggest active bleeding. Th e causes for post-cardiopulmonary bypass platelet dysfunction are thought to be multifactorial, including heparin suppression of platelet activation secondary to thrombin inhibition, hypothermia, and the physical shearing stress on platelets during cardiopulmonary bypasS.
A precordial Doppler can detect a minimal of ___ mL of intracardiac air: A. 0.1 B. 0.25 C. 0.5 D. 1
B. A precordial Doppler can detect as little as 0.25 mL of intracardiac air. A precordial Doppler is the next best sensitive indicator to detect intracardiac air after a transesophageal echocardiogram
A sudden drop in somatosensory-evoked potentials (SSEPs) would cause you to be worried about: A. Damage to the anterior spinal artery B. Damage to the posterior spinal arteries C. An insufficient depth of anesthesia D. The inadvertent administration of a neuromuscular blocking agent
B. SSEPs monitor the posterior spinal column, which would be affected by damage to the posterior spinal arteries or compression of the posterior spinal cord. A light plane of anesthesia would not cause a drop in SSEPs, nor would the administration of a neuromuscular blocking agent (the latter would hinder the use of motor-evoked potentials).
The correct statement for human neuraxial anatomy is A. Adult spinal cord ends at L2 B. Spinal cord in children ends at L3 C. The dural sac and subarachnoid space in adults end at S1 D. The dural sac and subarachnoid space in children end at S2
B. The spinal cord typically ends around L1 in adults, and around L3 in children. This is the reason why neuraxial blocks are performed below these levels and carry a lower risk of direct spinal cord injury. The dural sac and subarachnoid spaces end at S2 in adults and S3 in children.
How much local anesthetic should be administered per spinal segment to patients between 20 and 40 years of age receiving epidural anesthesia? A. 0.5 mL B. 1.0mL C. 1.5mL D. 2mL E. 2.5mL
B. 1.0mL Each milliliter of local anesthetic will anesthetize about one spinal segment. For example, if in a parturient undergoing caesarean section 15 mL of 3% chloroprocaine were injected through an epidural placed at L2-L3, about 15 segments would be anesthetized. Two thirds of these would be above the epidural entry site and one third would be below.
Ó requirement for a 70-kg adult under general anesthesia is A. 150 mL/min B. 250 mLlmin C. 350 mLlmin D. 450 mLlmin E. 550 mLlmin
B. 250 mLlmin The Ó requirement for an adult under general anesthesia is 3 to 4 mLlkg/min. The Ó requirement for a newborn under general anesthesia is 7 to 9 mLlkglmin. Alveolar ventilation (VA) in neonates is double that of adults to help meet their increased Ó requirements. This increase in VA is achieved primarily by an increase in respiratory rate as tidal volume (VT) is similar to that of adults. Although CÓ production also is increased in neonates, the elevated V A maintains the Pacó near 38 to 40 mm Hg.
A supraclavicular block of the brachial plexus does not provide consistent surgical anesthesia for shoulder surgery secondary to potential sparing of which of the following nerve branches of the brachial plexus? A. Musculocutaneous and axillary nerve branches B. Axillary and suprascapular nerve branches C. Ulnar and axillary nerve branches D. Suprascapular and supraclavicular nerve branches
B. A supraclavicular approach to brachial plexus blockade does not consistently and reliably provide anesthesia/analgesia to the axillary and suprascapular nerve branches. Therefore, a supraclavicular block can be used for postoperative analgesia, but may not be ideal for surgical anesthesia during invasive shoulder procedures. Sparing of ulnar nerve during a supraclavicular block may also occur that would not provide effective anesthesia for procedures distal to the mid-humerus.
The estimated maintenance fluid requirement for a 9-year-old, 35-kg patient is A. 50 mL/h B. 75 mL/h C. 100 mL/h D. 20 mL/h
B. 75 mL/h According to the "4-2-1 rule," 75 mL/h would be the maintenance rate. This is calculated as 40 + 20 + 15 = 75 mL/h (Table 5-2).
The most appropriate nerve block for pain management in a patient scheduled for a total hip replacement is: A. Femoral nerve block B. Lumbar plexus block C. Femoral and obturator nerve block D. Femoral and lateral femoral cutaneous nerve block
B. A femoral block for hip surgical procedures have intrinsic limitations as does not completely cover ALL dermatome distributions of the hip. A properly placed and functioning lumbar plexus blockade/catheter will cover the femoral, obturator, and lateral femoral cutaneous nerve and often provides for better pain control of the hip in conjunction with a sciatic/sacral nerve plexus block.
A line-isolation monitor A. Warns that an electrical shock is imminent B. Warns of a fault between the power line and the ground C. Warns of the presence of two faults D. Trips the ground leakage circuit breaker
B. A line-isolation monitor, when alarming, indicates that a single fault has occurred between the power line and the ground. As soon as the alarm is triggered, the equipment should be checked, especially the last equipment that was plugged in. A single fault does not cause an electrical shock, as two faults are required to produce a shock.
If the isofturane vaporizer dial is set to deliver 1.15% in Denver, Colorado (barometric pressure 630 mm Hg), how many MAC will the patient receive? A. About 20% more than 1 MAC B. About 10% more than 1 MAC C. One MAC D. About 10% less than 1 MAC E. About 20% less than I MAC
B. About 10% more than 1 MAC.
The causes of the oxyhemoglobin dissociation curve shifting to the right include all of the following except (Choose 3) A. Acidosis B. Alkalosis C. Decrease 2,3 DPG D. Fetal hemoglobin E. Voltatile anesthetics F. Hyperthermia
B. Alkalosis C. Decrease 2,3 DPG D. Fetal hemoglobin
All of the following medication adjuvants can be used in combination with local anesthetic solutions during performance of a peripheral nerve blockade to extend the duration/effectiveness of nerve blockade, except A. Epinephrine B. Ketamine C. Dexamethasone D. Clonidine
B. All of the above adjuvant medications, except ketamine, are commonly used in peripheral nerve blocks to improve the density and prolong the duration of nerve blockade efficacy. Ketamine, along with ephedrine, when mixed with local anesthetics during a peripheral nerve block has been studied in animal models and was deemed to offer little to no additional benefits or synergistic effects.
The following local anesthetic medication is associated with the highest risk for cardiovascular collapse in the event of local anesthetic systemic toxicity (LAST) A. Lidocaine B. Bupivacaine C. Ropivacaine D. Mepivacaine
B. Bupivacaine is best known for its high cardiovascular toxicity, although any of the local anesthetic medications listed above can result in LAST. One of the reported advantages of ropivacaine over bupivacaine is its relatively lowered incidence of cardiovascular toxicity. The other listed local anesthetic medications tend to have neurological toxicity prior to progressing toward cardiovascular collapse.
A 30-year-old male is found unresponsive outside a supermarket. The emergency response team finds him in ventricular fibrillation. After 10 minutes of CPR, the emergency response team is successful in reviving the patient. In the emergency room, it is decided to cool the patient to 34°C from 37°C. By this measure, the cerebral metabolic demand will decrease by A. 12% B. 18% C. 24% D. 30%
B. Cerebral metabolic rate decreases by 6% per degree Celsius decrease in body temperature below 37°C. Hence, a 3°C drop in temperature will decrease the cerebral metabolic rate by 18%.
A chronic alcoholic patient with liver cirrhosis is likely to demonstrate all of the following during administration of anesthesia, except A. A high minimum alveolar concentration (MAC) for desflurane B. Opioid hyperalgesia C. Resistance to the hypnotic effects of thiopental D. Resistance to the analgesic effects of opiates
B. Certain physiologic and pathologic states may alter MAC of inhaled anesthetics. MAC is higher in infants and lower in the elderly. Also, MAC increases with hyperthermia, alcoholism, and thyrotoxicosis. Furthermore, hypothermia, hypotension, and pregnancy seem to decrease MAC, while duration of anesthesia, gender, height, and weight seem to have little effect on MAC. Those with chronic liver disease are also at increased risk of arterial-venous shunting
Which ester local anesthetic (LA) is partially metabolized by the liver? A. Procaine B. Cocaine C. Mepivacaine D. Tetracaine
B. Cocaine Metabolism of cocaine occurs primarily in the liver with about 1% being excreted in the urine.
The most common nonhemolytic reaction to transfusion of blood products is A. Allergic B. Febrile C. Anaphylactoid D. Urticaria
B. Febrile reactions are the most common adverse nonhemolytic reaction and occur with 0.5% to 1% of transfusions. The most likely cause is an interaction between the recipient's antibodies and the antigen present on the leukocytes of platelets of the donor. The patient's temperature rarely increases above 38°C, and the condition is treated by slowing the infusion and administering antipyretics. Severe febrile reactions accompanied by chills and shivering may require discontinuation of the blood transfusion.
Which of the following is an inappropriate anesthetic solution for the spinal component of a combined spinal/epidural technique? A. Hyperbaric B. Hypobaric. C. Isobaric.
B. Hypobaric. Hypobaric has potential to cause high spinal.
In healthy patients, the lactate in lactated Ringer solution A. Causes a lactic acidosis B. Is converted to bicarbonate by the liver C. Is rapidly bound by albumin D. Causes a hyperchloremic metabolic acidosis
B. In healthy patients the lactate in lactated Ringers solution is rapidly converted to bicarbonate by the liver and does not cause a lactic acidosis. Administration of a large volume of normal saline can cause a hyperchloremic metabolic acidosis. Lactate is not bound by albumin
Which of the following system prevents the wrong gas cylinder being attached to the anesthesia machine? A. Diameter index safety system B. Pin index safety system C. Hanger yoke assembly system D. Gauge-safety system
B. Pin index safety system Cylinder manufactures have adopted the pin index safety system, which prevents attachment of wrong gas cylinder to the anesthesia machine. The diameter index safety system prevents attachment of the wrong gas hose from the wall supply. Hanger yoke assembly is the method of attachment of gas cylinders to the anesthesia machine.
A 25-year-old patient with severe depression is undergoing an electroconvulsive therapy (ECT). The duration of seizure can be increased by A. Hypoventilating the patient B. Hyperventilating the patient C. Administering succinylcholine D. Administering rocuronium
B. Propofol when used for induction in patients undergoing ECT can increase the seizure threshold and decrease the duration of the seizure. Hyperventilation and administration of caffeine or etomidate can increase seizure duration. Muscle relaxants do not affect the threshold or duration of the seizure.
Pulse oximetry illuminates tissue samples with two wavelengths of light in order to calculate oxygen saturation. These wavelengths are ______ nm: A. 540 and 780 B. 660 and 940 C. 720 and 960 D. 480 and 720
B. Pulse oximetry uses two wavelengths of light to calculate oxygen saturation. These wavelengths are 660 nm of red light (well absorbed by oxygenated hemoglobin) and 940 nm of infrared light (well absorbed by deoxygenated hemoglobin.
Serious complications with transesophageal echocardiography (TEE), such as oral or pharyngeal injury or esophageal rupture, have an incidence as high as: ' A. 0.01% B. 0.1% C. 1% D. 10%
B. Serious complications with TEE have been reported in approximately 0.1% of cases, or approximately 1 in 1,000 patients. Strict contraindications to TEE include but are not limited to esophageal spasm, esophageal stricture, esophageal laceration, esophageal perforation, and esophageal diverticulum. Relative contraindications include but are not limited to upper GI bleed, dysphagia or odynophagia, mediastinal radiation, large diaphragmatic hernias, atlantoaxial disease, and difficult intubation due to possibility of unintentional extubation with probe manipulation.
A patient with chronic liver disease is scheduled for a laparoscopic abdominal operation. The risk of mortality during surgery for this patient is assessed using A. Mayo end-stage liver disease B. Child-Turcotte-Pugh score C. Ranson criteria D. Alvarado score
B. The Child-Turcotte-Pugh score is used to predict mortality during surgery in patients with chronic liver disease, namely, cirrhosis. The Mayo or model for endstage liver disease was initially developed to predict death within 3 months of surgery in patients who had undergone a transjugular intrahepatic portosystemic shunt procedure and was subsequently found to be useful in determining prognosis and prioritizing patients for liver transplant. Alvarado score is used for appendicitis, while the Ranson criteria assess pancreatitis
The femoral nerve provides sensory innervation to the A. Lower extremity below the knee B. Anterior and medial thigh C. Posterior and medial thigh D. Almost the entire ankle
B. The femoral nerve provides sensory innervation to the anterior and medial thigh above the knee, and medial side of the lower extremity below the knee. The femoral nerve innervates and supplies motor control of the anterior quadriceps muscles above the knee and no motor innervation below the knee.
Bone marrow depression and peripheral neuropathy have been associated with prolonged exposure to anesthetic concentrations of: A-isoflurane B-desflurane C-sevoflurane D-nitrous oxide
Bone marrow depression and peripheral neuropathy have been associated with prolonged exposure to anesthetic concentrations of: B-nitrous oxide By irreversibly oxidizing the cobalt atom in vitamin B12, nitrous oxide inhibits vitamin B12 dependent enzymes. These enzymes include methionine synthetase and thymidylate synthetase. As a result of these enzyme inhibitions, prolonged exposure to nitrous oxide has been associated with bone marrow depression, megaloblastic anemia, peripheral neuropathy and teratogenicity.
A patient requires emergency surgery immediately following a traumatic spinal cord transection at C3. Anesthestic implications include: (Select 2) A- tachycardia B- Hypertension. C- Respiratory failure. D- Hypothermia.
C- Respiratory failure. D- Hypothermia. This patient is at risk for spinal (Neurogenic shock). Presentation: Bradycardia, decreased SNS tone (Vasodilation, venous pooling, hypotension), impairement of SNS output (inability to vasoconstriction or shiver resulting in hypothermia). Pluss C3 puts patients at risk or respiratory failure from diaphragmatic parlysis.
For each 1°C decrease in body temperature, how much will cerebral metabolic rate for oxygen (CMR02) be diminished? A. 3% B. 5% C. 6% D. 10% E. 20%
C) CMR02 decreases approximately 6% per 1°C of temperature reduction. Hypothermia has been reported to improve neurologic outcome after focal or global brain ischemia. Historically, the extent of brain protection was thought to be proportional to the magnitude of hypothermiamediated reduction in CMR02• However, more recent studies have demonstrated that temperature reductions of a mere 1 ° to 2°C significantly improve postischemic neurologic outcome.
Which of the following rotameter flow indicators is read in the middle of the dial? A. Bobbin B. "H" float C. Ball float D. Skirted float E. Nonrotating float
C) Five types of rotameter indicators are commonly used to indicate the flow of gases delivered from the anesthesia machine. As with all anesthesia equipment, proper understanding of their function is necessary for safe and proper use. All rotameter flow indicators should be read at the upper rim except ball floats, which should be read in the middle.
Which of the following is the primary determinate of carbon dioxide elimination. A- Respiratory rate B- Minute ventilation C- Alveolar ventilation D- Tidal volume
C- Alveolar ventilation
Laminar flow in the airway occurs in the: (Select 2) A- trachea B-main stem bronchi C-terminal bronchiole D-3rd generation bronchus E-respiratory bronchiole
C-terminal bronchiole, E-respiratory bronchiole. Flow in the larger airways is mostly turbulent. Laminar flow normally occurs only distal to small bronchioles (< 1mm). The Reynolds number is used to predict the type of airway flow; a low Reynolds number (< 1000) is associated with laminar flow, whereas a high value (> 1500) is associated with turbulent flow.
Laminar flow in the airway occurs in the: (Select 2) A-trachea B-main stem bronchi C-terminal bronchiole D-3rd generation bronchus E-respiratory bronchiole
C-terminal bronchiole, E-respiratory bronchiole Flow in the larger airways is mostly turbulent. Laminar flow normally occurs only distal to small bronchioles (< 1mm). The Reynolds number is used to predict the type of airway flow; a low Reynolds number (< 1000) is associated with laminar flow, whereas a high value (> 1500) is associated with turbulent flow.
A 76-year-old man is scheduled for a hemicolectomy. His past medical history is significant for third degree heart block treated with a permanent pacemaker. Problems with electrocautery use in this patient can be minimized by: A-placing the grounding pad near the pacemaker B-using infrequent bursts of longer duration C-the use of a bipolar cautery D-reducing the surface area of the return electrode
C-the use of a bipolar cautery Electrical interference from the electrocautery can be interpreted by the pacemaker as myocardial activity and suppress pacemaker activity. These problems can be minimized by limiting use to short bursts, placing the grounding pad as far from the pacemaker as possible and using a bipolar cautery.
During fetal monitoring, Type III decelerations are thought to be related to: A-head compression B-umbilical cord compression C-uteroplacental insufficiency D-placental abruption
C-umbilical cord compression Type III, or variable, decelerations are the most common type of decelerations. They are thought to be related to umbilical cord compression and intermittent decreases in umbilical blood flow.
Halfway through a complex pancreatectomy, the surgeon asks you to administer a couple of liters of Hetastarch because he would like the patient extubated at the end of surgery. Estimated blood loss is 1 L and the patient has already received 6 L of crystalloid. She is 70 kg. Your best response would be which of the following? A. You tell the surgeon she has already received too much crystalloid to be extubated. B. You agree to administer Hetastarch because it improves renal function and reduces interstitial fluid edema, which could complicate extubation. C. You do not agree to administer Hetastarch because it can cause coagulopathy, leading to increased surgical blood loss. D. You do not agree to administer Hetastarch because the pancreatectomy will impair the patient's ability to handle the hyperglycemia caused by the degradation of Hetastarch to glucose. E. You agree to administer Hetastarch because there are few to no side effects.
C. Hetastarch is a synthetic colloid in the family of hydroxyethyl starches (HES). It is derived from amylopectin-rich starch that undergoes hydroxyethylation to increase its water solubility and protect it from complete metabolism to glucose by amylase. By creating an osmotic gradient within the intravascular space, Hetastarch achieves eff ective volume expansion using less volume than crystalloid. Its volume expansion properties last for up to 24 hours before excretion by the kidneys. Hetastarch, a first-generation HES, is manufactured with large molecular weights (480 to 670 kDa) and a high degree of hydroxyethylation (molar substitution) to slow the rate of metabolism and elimination. These two properties, however, also appear to be responsible for its numerous side effects, including coagulopathy, anaphylactic reactions, renal impairment, and accumulation of byproducts. While the mechanism is uncertain, Hetastarch interacts with platelets and decreases factor VIII and von Willebrand factor, thus leading to a von Willebrand-like syndrome. This occurs in a dose-dependent fashion with signifi cant bleeding risk at doses greater than 20 mL/kg. Because this patient is 70 kg, the maximum recommended dose is 1,400 mL. Renal impairment likely occurs from the accumulation of these large molecules within the renal tubules.
Drugs that can decrease or reduce opioid-induced biliary spasm include all of the following, except A. Diltiazem B. Atropine C. Metoclopramide D. Glucagon
C. A variety of agents that can produce smooth-muscle relaxation have been used. Nitrates and calcium channel blockers have been the most extensively studied. Anticholinergics, including atropine and glucagon, are additional agents that can provide sphincter of Oddi relaxation. Metoclopramide is a promotility agent that enhances sphincter smooth-muscle contraction.
Clinically significant histamine release has been associated with the use of: A-vecuronium B-rocuronium C-cisatracurium D-atracurium
D-atracurium Atracurium has been associated with histamine release from mast cells and can result in bronchospasm, skin flushing and hypotension.
Spinal anesthesia was performed on a 25-year-old healthy male for ureter stent placement. A total of 1.5 mL of 5% preservative-free lidocaine in 7.5% dextrose was injected intrathecally after being mixed with CSF. There was evidence of free CSF flow before and after injection. The surgery was performed in the lithotomy position and was uneventful, but the patient complained of severe buttock pain in the post- anesthesia care unit. A neuro exam was negative for sensory and motor deficits. The most likely diagnosis is A. Spinal hematoma B. Spinal abscess C. Transient neurological symptoms D. Radiculopathy
C. Although transient neurological symptoms are usually self-limiting, it can be bothersome to patients. The etiology is mostly likely due to the high concentration of lidocaine; therefore, 5% lidocaine is now avoided in spinal anesthesia when possible
Lidocaine and epinephrine are commonly used together when testing epidural anesthesia because A. Lidocaine injection (3 mL of 1.5%) intravascularly will induce local anesthetic toxicity such as perioral numbness. B. Intrathecal injection of epinephrine will result in a high spinal C. Intrathecal injection of lidocaine can cause a low-level spinal anesthesia with some degree of motor block D. Intravascular injection of epinephrine (typically 15 μg/3 mL) can cause hypertension more than tachycardia.
C. A total of 3 mL of 1.5% lidocaine with 1:200,000 epinephrine is commonly used when testing for epidural anesthesia to rule out intrathecal (lidocaine can result in spinal blockade) and/or intravascular injection. Intravascular injection of epinephrine (15 μg) can result in a transient increase in heart rate of 20% or higher, within 30 seconds of injection and without evidence of a BP change
While monitoring a patient for return of neuromuscular function after using rocuronium, you notice the patient has regained four twitches using train of four stimulations. With four twitches on train of four stimulations, the patient may still have blockage of acetylcholine receptors of up to: A. 25% B. 50% C. 75% D. 90%
C. Understanding the limitations of neuromuscular twitch monitoring devices is fundamental for an anesthesia provider. At the point the fourth twitch reappears, still up to 75% to 80% of acetylcholine receptors may be blocked. Adequate reversal (neostigmine-glycopyrrolate) should be given, and clinical signs for return of neuromuscular function should be used to gauge readiness for extubation.
All of the following are signs of dehydration, except A. Progressive metabolic acidosis B. Urinary specific gravity > 1.010 C. Urine osmolality < 300 mOsm/kg D. Urine sodium < 10 mEq/L
C. When dehydrated, patients with normal renal function will retain sodium and produce a concentrated urine. Urine osmolality is typically greater than 450 mOsm/kg in this setting. Urine sodium will be low, and specific gravity will be high.
During laparoscopic cholecystectomy, the risk of failure to visualize contrast material entering the duodenum during intraoperative cholangiogram is highest with the administration of A. Buprenorphine B. Nalbuphine C. Morphine D. Naloxone
C. μ-Receptor agonism may contribute to sphincter of Oddi spasm, preventing passage of contrast with full μ-agonist more likely to contribute versus partial μagonists (e.g., buprenorphine) and agonist-antagonist (e.g., nalbuphine). Naloxone, as a μ-antagonist would alleviate any opioid-induced spasm.
Calculate the Vd/Vt ratio (physiologic dead-space ventilation) based on the following data: Pacó 45 mm Hg, mixed expired CÓ tension (PEcó) 30 mm Hg. A. 0.1 B. 0.2 C. 0.3 D. 0.4 E. 0.5
C. 0.3 Physiologic dead-space ventilation can be estimated using the Bohr equation (described in the explanation to question 103): VO/VT = 45 mm Hg - 30 mm Hg = 15 mm Hg = 0.33 45 mmHg 45 nunHg
The likelihood of a clinically significant hemolytic transfusion reaction resulting from administration of erythrocytes to a patient with a negative antibody screen is less than A. 1 in 100 B. 1 in 1000 C. 1 in 10,000 D. 1 in 100,000 E. 1 in 1,000,000
C. 1 in 10,000
Malfunction of which of the following valves within a circle system may cause rebreathing of carbon dioxide and could potentially result in hypercapnia? A. Inspiratory valve B. Expiratory valve C. Both A and B D. None of the above
C. Both A and B Malfunction in either of the unidirectional valves within a circle system could result in the accumulation and eventual CÓ rebreathing that may result in hypercapnia
What pressure should not be exceeded when performing Positive pressure ventilation with a mask? A. 10 cm/H20 B. 15 cm/H20 C. 20 cm/H20 D. 25 cm/H20
C. 20 cm/H20 Increased risk of abdominal insufflation. Aspiration risk.
A 20-kg, 5-year-old child with a hematocrit of 40% could lose how much blood and still maintain a hematocrit of 30%? A. 140 mL B. 250 mL C. 350mL D. 450mL E. 550 mL
C. 350mL
A 21-year-old patient reports tingling in her thumb during cesarean section under epidural anesthesia. To which dermatomal level would this correspond? A. C4 B. C5 C. C6 D. C7 E. C8
C. C6 The thumb corresponds to dermatome C6, the middle finger corresponds to dermatome C7, and the little finger corresponds to dermatome C8
Pipeline gases are supplied at pressures of about ______ psi: A. 25 B. 40 C. 50 D. 75
C. 50 Pipeline gases are supplied at pressures between 45 and 55 psi. This is in contrast to cylinder gas pressures, which are much higher, and are reduced by pressure regulators to less than 50 psi
The oxygen-flush valve provides which of the following oxygen flows (L/min) to the common gas outlet? A. 10 B. 25 C. 50 D. 90
C. 50 The oxygen-flush valve provides gas flow at pipeline pressures of about 45 to 55 psi at 35 to 75 L/min. The high flow of oxygen is provided directly to the common gas outlet, bypassing the flowmeters and vaporizers. One should be careful when using the oxygen-flush valve, as high gas flows at high pressures can cause lung barotrauma in the patient
What driving pressure is needed to generate sufficient gas flow when a 12 or 14 gauge catheter is used during jet ventilation with an emergency cricothyrotomy? A. 30 psi B. 40 psi. C. 50 psi. D. 60 psi.
C. 50 psi.
True statement about cerebrospinal fluid (CSF) is A. It is formed in the third ventricle B. It is absorbed in arachnoid granulations present in fourth ventricle C. Total volume of CSF is about 150 mL D. Major mechanism of formation is by passive diffusion of ions
C. CSF is formed by the choroid plexuses of cerebral lateral ventricles. In adults, normal CSF production is about 20 mL/hour with a total volume of 150 mL. The CSF is absorbed in arachnoid granulations over cerebral hemispheres. CSF formation involves active secretion of sodium in the choroid plexuses, and not passive diffusion.
Capacity of an oxygen "E" cylinder is approximately ______ L: A. 500 B. 600 C. 650 D. 750
C. 650 The capacity of an "E" cylinder of oxygen is about 625 to 700 L. The pressure in a full cylinder is about 1,800 psi at 20°C. Cylinders are color-coded, with oxygen being green, nitrous oxide being blue, and air being yellow
Following successful performance of a right interscalene block for surgical rotator cuff repair in a 27-year-old patient with no other medical issues, you are called to the recovery room (post-anesthesia care unit) 3 hours later to evaluate the patient. The patient's symptoms include drooping of the right eyelid, redness of the conjunctiva, and pupillary constriction. The most likely diagnosis is A. Spinal anesthesia B. Subdural injection of local anesthetic C. Horner syndrome D. Cerebrovascular accident (CVA)
C. A Horner syndrome (miosis, ptosis, and anhidrosis) can be commonly seen following an interscalene block. This syndrome is often due to proximal tracking of local anesthetic and blockade of the sympathetic fibers to the cervicothoracic ganglion. In patients where a CVA may also be within the differential diagnosis, a thorough history and neural exam should always be included.
Which of the following cardiovascular abnormalities is least likely to be present in a patient with end-stage alcoholic cirrhosis A. Resting tachycardia B. Widened pulse pressure C. Increased peripheral vascular resistance D. Increased cardiac output
C. Cirrhosis is typically associated with several cardiovascular abnormalities including a hyperdynamic circulation characterized by increased cardiac output and decreased peripheral resistance. Other cardiovascular changes include a resting tachycardia, warm peripheries, a bounding pulse, and a widened pulse pressure.
The neuromuscular blocking agent relatively contraindicated in a patient with raised intracranial pressure (ICP) is A. Rocuronium B. Vecuronium C. Atracurium D. Cisatracurium
C. In a patient with increased intracranial pressure, a nondepolarizing muscle relaxant is commonly used to facilitate controlled ventilation and tracheal intubation. Rocuronium and vecuronium are commonly used as they provide the greatest hemodynamic stability. Succinylcholine and atracurium (due to associated histamine
In a patient undergoing craniotomy, the transducer of arterial line should be zeroed at the: A. Level of hypothalamus B. Level of heart C. Level of external auditory meatus D. Level of atmosphere
C. In a seated patient, the arterial pressure in the brain differs significantly from left ventricular pressure. Cerebral perfusion pressure is determined by setting the transducer to zero at the level of the ear, which approximates the circle of Willis
When are digit blocks most commomly used? A. For compartment syndrome B. To burn off warts. C. In the ER for lacerations. D. In the ICU for glucose test
C. In the ER for lacerations.
A 16-year-old patient with acute lysergic acid diethylamide (LSD) intoxication and head injury comes to emergency room. All the following can be used in anesthetic management, except A. Propofol B. Succinylcholine C. Ketamine D. Phenylephrine
C. LSD is a hallucinogen and causes CNS excitation, sensory distortion, delusions, hallucinations, and euphoria. Autonomic effects, mediated via the hypothalamus, include tachycardia, hypertension, mydriasis, piloerection, salivation, lacrimation, and vomiting. In view of hypertension and tachycardia that can be caused by LSD, ketamine should be avoided
You successfully perform and place a bilateral T8 continuous paravertebral block catheters for an open-partial hepatectomy. Eighteen hours postoperatively, the patient complains of 7/10 pain. To improve postoperative analgesia, 10 mL of 0.2% ropivacaine is administered through each catheter. Twenty minutes later, the patient indicates that the pain has decreased to 4/10. The most likely aspect of paravertebral blockade that can account for the reason why the patient did not achieve a pain-free condition is A. The block level was too high; it should have been placed at the T10 level B. The block level is too low; it should have been placed at the T6 level C. Paravertebral blockade analgesia provides for mostly somatic blockade and does not provide for complete coverage of visceral pain D. The local anesthetic volume administered is too small
C. Paravertebral blockade provides mostly for somatic-induced pain with little visceral pain coverage; therefore, hepatectomy patients need additional painmanagement modalities such as opioids
Which of the following are increased in the serum of the patient with renal osteodystophy : A. Calcitriol B. Calcium C. Phosphate D. Parathyroid hormone
C. Phosphate D. Parathyroid hormone
Neuraxial block complications using local anesthetics alone include all of the following, except A. Post-dural puncture headache B. Urinary retention C. Postoperative cognitive dysfunction D. High spinal anesthesia.
C. Postoperative cognitive dysfunction Potential complications of neuraxial blockade can be diverse and range from death, cardiac arrest, seizures, paraplegia, radiculopathy, anterior spinal artery syndrome, high/total spinal anesthesia, arachnoiditis, post-dural puncture headache, back pain, epidural hematoma, and epidural abscess. However, complication rates are low and patients do not typically experience delirium unless systemic opioid analgesics have been used
A patient with type O blood will have which of the following plasma antibodies? A. Anti-A B. Anti-B C. Both anti-A and anti-B D. None
C. Routine typing of blood is performed to identify the antigens (A, B, Rh) on the membranes of erythrocytes. Naturally-occurring antibodies (anti-B, anti-A) are formed whenever erythrocyte membranes lack A or B antigens (or both). These antibodies are capable of causing rapid intravascular destruction of erythrocytes that contain the corresponding antigens.
The electrophysiological monitor most resistant to anesthetic agents is A. Somatosensory-evoked potentials B. Motor-evoked potentials C. Brain-stem auditory-evoked potentials D. Electroencephalography
C. Somatosensory- and motor-evoked potential monitoring is commonly used to detect ischemia of spinal cord in spine surgeries. Brain-stem auditory-evoked responses monitor ischemia during posterior fossa surgeries. Inhalational agents in general increase the latency and decrease the amplitude of evoked potentials (if used at more than 0.5-0.75 MAC). The effect of inhalational anesthetics on evoked potentials in decreasing order is visual > motor > somatosensory > brain-stem auditory
When evaluating regurgitant lesions with transesophageal echocardiography, the Nyquist limit should be set between ______ cm/s: A. 30 and 40 B. 40 and 50 C. 50 and 60 D. 60 and 70
C. The current guidelines recommend a Nyquist limit of 50 to 60 cm/s when evaluating regurgitant lesions. Setting the limit to low could result in overestimating the regurgitant lesion, and setting the limit to high could result in underestimating the regurgitant lesion.
You have just performed a femoral nerve block in preparation for a tibial plateau fracture repair using 20 mL 0.5% ropivacaine. Three hours postsurgery in the recovery room, the patient complains of lateral thigh pain. Was the femoral nerve block a failure and what would be the most appropriate action? A. Yes, repeat the femoral nerve block due to a failed block. B. No, repeat the femoral nerve block as the effectiveness of the local anesthetic has worn off after 4 hours C. No, the pain expressed is not located within the distribution of the femoral nerve, supplement with a lateral femoral cutaneous nerve block D. Yes, the pain is due to a failed femoral block, but do not repeat the block as there exists a high risk of nerve injury.
C. The lateral femoral cutaneous nerve supplies the lateral portion of the thigh. Blockade of the lateral femoral cutaneous nerve is not always consistently blocked with femoral nerve block approach, but can be blocked separately if/when needed.
The stellate ganglion lies in closest proximity to which of the following vascular structures? A. Common carotid artery B. Internal carotid artery C. Vertebral artery D. Axillary artery E. Aorta
C. Vertebral artery
The alderate modified post anesthesia recovery score qualifies all of the following criteria except: A- Consciousness B- Respiration C- Activity D- Temperature.
D- Temperature. Consist of :Activity, Consciousness, Circulation, Respiratory, Oxygen saturation
Sickle hemoglobin: (Select 2) A-has a lower P50 than hemoglobin A B-releases oxygen less readily than hemoglobin A C-is present in about 30% of African Americans D-readily polymerizes and precipitates in the red cell E-results from a single amino acid substitution on the α-chain F-has decreased solubility as compared to hemoglobin A
D-readily polymerizes and precipitates in the red cell. F-has decreased solubility as compared to hemoglobin A. Sickle hemoglobin (HbS) has a lower affinity for oxygen and an elevated P50 (31 mm Hg) as compared to hemoglobin A (27 mm Hg). HbS also has decreased solubility and readily polymerizes and precipitates in the red cell producing the sickled appearance of the cell. HbS results from the substitution of valine for glutamic acid on the β-chain.
Sickle hemoglobin: (Select 2) A-has a lower P50 than hemoglobin A B-releases oxygen less readily than hemoglobin A C-is present in about 30% of African Americans D-readily polymerizes and precipitates in the red cell E-results from a single amino acid substitution on the α-chain. F-has decreased solubility as compared to hemoglobin A
D-readily polymerizes and precipitates in the red cell. F-has decreased solubility as compared to hemoglobin A. Sickle hemoglobin (HbS) has a lower affinity for oxygen and an elevated P50 (31 mm Hg) as compared to hemoglobin A (27 mm Hg). HbS also has decreased solubility and readily polymerizes and precipitates in the red cell producing the sickled appearance of the cell. HbS results from the substitution of valine for glutamic acid on the β-chain.
The factor associated with maximum increase in intracranial pressure (ICP) is A. Increased central venous pressure to 14 mm Hg B. Hypercarbia with PaCÓ of 50 mm Hg C. Ventilation with positive end-expiratory pressure (PEEP) of 5 cm H2O D. Bucking and coughing on endotracheal tube.
D. Intracranial pressure is supratentorial CSF pressure measured in the lateral ventricles or cerebral cortex. Normal ICP is 10 mm Hg or less. Between PaCÓ values of 20 and 80 mm Hg, CBF increases by 1 mL/100 g/min and cerebral blood volume increases by 0.05 mL/110g/min per mm Hg increase in PaCÓ. Increase in CVP and adding PEEP will minimally increase ICP by affecting venous return. Coughing and bucking can cause a much higher increase in ICP (acute increase) than any of the above factors
A 50-year-old male patient is to undergo an open nephrectomy for renal carcinoma. The patient requests an epidural for perioperative pain management, as he is strongly intolerant to μ-agonist opiate therapy with nausea and vomiting. After a T2 sensory level is obtained, the patient is induced with propofol 200 mg and rocuronium 70 mg,followed by tracheal intubation. The expected response to intubation in this patient includes A. Hypertension B. Tachycardia C. Tachypnea D. Mydriasis
D. High thoracic epidural blockade up to T2 blocks the cardiac accelerators, providing adequate sympathectomy to prevent hypertension and tachycardia. Sympathetic outflow to the pupil travels via the intermediolateral cell column at the C8 to T2 cord level and remains intact; thus, the sympathetic surge can still result in mydriasis.
Complications from neuraxial blockade may include all of the following, except A. Radiculopathy B. Anterior spinal artery syndrome C. Arachnoiditis D. Constipation
D. Complications from neuraxial blockade can be diverse and range from death, cardiac arrest, seizures, paraplegia, radiculopathy, anterior spinal artery syndrome, high/total spinal anesthesia, arachnoiditis, post-dural puncture headache, back pain, epidural hematoma, epidural abscess, and urinary retention. However, the complication rates are typically low and may even improve bowel function and decrease constipation
Factors influencing the level of spinal anesthesia achieved include all of the following, except A. Baricity of anesthetic solution B. Patient age C. Volume of anesthetic solution injected D. Patient gender
D. Major factors influencing the level of spinal anesthesia includes baricity of local anesthetic solution, patient position immediately following spinal block placement, drug dose used, site of injection, patient age and spine anatomy, pH of the CSF, drug volume used, needle orifice direction, patient height, and patients being pregnant.
Modern vaporizers are: A. Agent-specific B. Temperature-compensated C. Pressure-compensated D. Both A and B
D. Modern vaporizers are agent-specific and temperature-compensated. Also, specific fillers are available for each volatile agent, which prevent filling on the wrong agent. A constant concentration of agent is delivered, unaffected by temperature or flow rates. Temperature compensation is achieved by a metallic strip composed of two different metals, which expands/contracts to deliver a constant concentration of vapor.
Each of the following would be expected in an otherwise-healthy 125-kg (BMI 40 kg/m2) man undergoing open cholecystectomy, except A. Decreased functional residual capacity B. Increased intra-abdominal pressure and risk of reflux C. Increased metabolism of volatile anesthetics D. Decreased metabolism of atracurium
D. Perioperative morbidity related to obesity is associated with changes in respiratory (e.g., difficult airway, decreased functional residual capacity), cardiovascular (e.g., increased cardiac output), and gastrointestinal (e.g., gastroesophageal reflex disease, increased abdominal pressure) systems that will impact the delivery of anesthesia. Given that metabolism of inhalational agents is increased over normal weight patients, higher minimum alveolar concentrations may be required. Atracurium (including cis-atracurium) is metabolized via Hofmann degradation and is unaffected by the obese state.
The variable not used to calculate an MELD (model for end-stage liver disease) score to prioritize patients for liver transplantation is A. Creatinine B. INR (international normalized ratio) C. Bilirubin D. Albumin
D. The MELD score is a formulaic calculation utilizing three variables: creatinine, INR, and bilirubin. For dialysis-dependent patients, the creatinine score is automatically set to 4 mg/dL despite true serum levels. MELD score = 10 × [0.957 × log e (creatinine) + log e (bilirubin) + 1.12 × log e (INR)] + 6.43
If pressure in a full nitrous oxide "E" cylinder is 745 psi at 20°C, the pressure in a half-full cylinder will be about ______ psi: A. 186 B. 248 C. 372 D. 745
D. 745 Pressure in a half-full "E" cylinder of nitrous oxide will still be 745 psi. Nitrous oxide is present in the cylinder as a liquid, and therefore, the volume remaining in the cylinder does not reflect the pressure in the cylinder. Capacity of an "E cylinder" of nitrous is about 1590 L. It is not until three-fourth of the gas is consumed (about 400 L remaining) that the pressure in the cylinder begins to fall. Therefore, the reliable way to determine the remaining nitrous oxide in the cylinder is to weigh the cylinder. The empty weight of the cylinder is stamped on the cylinder.
Types of autologous blood transfusion include all of the following, except A. Predeposited donation B. Intraoperative blood salvage C. Normovolemic hemodilution D. Donor-directed transfusion
D. A directed (or designated) blood donation is one in which a patient selects his/her own blood donor(s) for an anticipated, nonemergency transfusion. The donor is typically a friend or relative to the patient. Patients undergoing elective procedures with a high probability of blood transfusion can donate their own blood 4 to 5 weeks prior to surgery, and this is referred to as a predeposited donation. Blood salvage refers to the collection of shed blood intraoperatively, which is then concentrated, washed, and transfused back to the patient. For normovolemic hemodilution, blood is removed just prior to surgery and replaced with crystalloid or colloid. The blood is stored for up to 6 hours, and then be given back to the patient after blood loss.
A properly placed psoas compartment block or posterior lumbar plexus block can be associated with any of the following complications, except A. Retroperitoneal hematoma B. Spinal anesthesia C. Local anesthetic systemic toxicity D. Sciatic nerve injury
D. A lumbar plexus block is considered a deep block and has been described as an advanced block in regional anesthesia. Some potential complications include retroperitoneal hematoma, local anesthetic systemic toxicity, intrathecal and/or epidural injections of local anesthetics, and renal injury (with potential for subsequent hematoma). The typical approach for lumbar plexus blockade should not cause injury to the sciatic nerve unless an improperly placed or misdirected regional block needle is positioned too caudad that could then result in injury to sacral plexus and the sciatic nerve.
All of the following qualities are advantages of crystalloid solutions, except A. Nontoxic B. Reaction-free C. Relatively inexpensive D. Have the ability to remain in the intravascular space for a relatively long amount of time.
D. Advantages of crystalloid solutions are that they are nontoxic, reaction-free, and inexpensive. Colloid solutions are composed of large-molecular-weight substances that remain in the intravascular space longer than crystalloids, and typically, the initial volume of distribution is equivalent to the plasma volume. The synthetic colloids and processed albumin have minimal or no risks of infection. Colloids are more expensive than crystalloids, but have fewer risks than blood products.
After blood is collected, the preservative CPDA-1 is commonly added. This contains all of the following, except A. Citrate B. Phosphate C. Dextrose D. Potassium
D. CPDA-1 is the most commonly added preservative added to blood products. It contains citrate as an anticoagulant, phosphate as a buffer, dextrose as a red blood cell energy source, and adenine needed for the maintenance of red cell ATP levels. The potassium found in blood comes from the breakdown of red blood cells.
The most correct statement concerning a unilateral paravertebral block is A. Such a block is always associated with a similar degree of sympathectomy as with an epidural block B. Such a block is often associated with a higher serum level of local anesthetic than that achieved with an intercostal nerve block due to high vascularity C. It is not likely to be associated with a pneumothorax D. Such a block may be associated with epidural spread of local anesthetic
D. Advantages of properly placed paravertebral nerve blocks include reduced degrees of local anesthetic-induced sympathectomy compared to epidural or spinal anesthesia and a lower risk of local anesthetic systemic toxicity as compared with intercostal nerve blocks. However, one of the major concerns for potential complications is development of a pneumothorax, and paravertebral blocks can be associated with variable degrees of local anesthetic epidural spread, especially when placing bilateral paravertebral blocks
A 36-year-old female patient is undergoing thyroidectomy under a deep cervical plexus nerve block. Which of the following complications would be least likely with this block? A. Homer's syndrome B. Subarachnoid injection C. Blockade of the recurrent laryngeal nerve D. Blockade of the spinal accessory nerve E. Blockade of the phrenic nerve
D. Blockade of the spinal accessory nerve. Complications of deep cervical plexus block include injection of the local anesthetic into the vertebral artery, subarachnoid space, or epidural space. Other nerves that may be anesthetized as a complication of this block include the phrenic nerve, recurrent laryngeal nerve, and the cervical sympathetic chain with resultant Homer's syndrome.
You are called to evaluate a 50-year-old patient for brain death. All the following are criteria for brain death, except: A. Apnea for 10 minutes B. Absence of corneal reflex C. Presence of spinal reflexes D. Decerebrate posturing
D. Brain death is irreversible cessation of all brain activity. Generally accepted clinical criteria for brain death include presence of coma, absence of motor activity, absence of brain-stem reflexes (papillary, corneal, vestibule-ocular, and gag/cough), absence of ventilatory effort (PaCÓ >60 mm Hg), exclusion of hypothermia or effect of sedatives, isoelectric EEG, and absence of cerebral perfusion by angiography
Which of the following local anesthetics would produce the lowest concentration in the fetus relative to the maternal serum concentration during a continuous lumbar epidural? A. Etidocaine B. Bupivacaine C. Lidocaine D. Chloroprocaine E. Mepivacaine
D. Chloroprocaine Because of the rapid hydrolysis of ester local anesthetics, very little drug is available to cross the placenta. Plasma cholinesterase activity can be reduced up to 40% in pregnant patients, yet the elimination half-life of chloroprocaine is little affected (ranging from 1.5 to 6 minutes).
Which of the following local anesthetics used for intravenous regional anesthesia (Bier block) is most rapidly metabolized and thus least toxic? A. Lidocaine B. Ropivacaine C. Mepivacaine D. Prilocaine E. Etidocaine
D. Prilocaine. Prilocaine is the most rapidly metabolized of the amide local anesthetics and therefore least toxic. 2-Chloroprocaine is hydrolyzed rapidly in the blood and, therefore, would appear to be
All the following are relative contraindications to a sitting craniotomy, except A. Right-to-left cardiac shunt B. Patent foramen ovale C. Ventriculoatrial shunt D. Ventriculoperitoneal shunt
D. The incidence of venous air embolism in sitting craniotomies is about 20% to 40%. The presence of right-to-left shunt can cause paradoxical air embolism. Air embolism can have catastrophic consequences, such as coronary ischemia and stroke. Thus, sitting position should be avoided in patients with a right-to-left shunt, patent foramen ovale, or ventriculoatrial shunt.
When considering the advantages and disadvantages of different sites for arterial cannulation such as radial, ulnar, femoral, brachial, and dorsalis pedis, the A. Radial artery provides the principal source of blood to the hand B. Cannulation of ulnar artery is commonly associated with damage to the median nerve C. Dorsalis pedis artery is commonly used during emergencies and low-flow states D. Cannulation of the femoral artery risks local and retroperitoneal hematoma
D. The ulnar artery is the principal source of blood flow to the hand. Hence radial artery cannulation is much more commonly used for invasive blood pressure monitoring. Cannulation of the brachial artery risks damage to the median nerve. The femoral artery is often used in emergencies, since it is a large vessel and can still be identified in low flow states. Cannulation of the femoral artery risks both local and retroperitoneal hematoma. Dorsalis pedis artery cannulation, while not ideal since it is far from the central circulation, can reliably measure mean arterial pressure
The rate of induction of anesthesia with isoflurane would be slower than expected in patients: (Select all that apply) A. With anemia B. With chronic renal failure C. In shock D. With cirrhotic liver disease With a right-to-Ieft E. intracardiac shunt
E only The depth of general anesthesia is directly proportional to the alveolar anesthetic partial pressure. The faster the rate of increase in F AlF'I, the faster the induction of anesthesia. With the exception of a right-to-left intracardiac shunt (see explanation to question 337 on effect of shunt on the rate of increase in F AlFI and explanation to question 346 on the effect of shunt on arterial anesthetic partial pressure and rate of induction of anesthesia), all of the conditions listed in this question will accelerate the rate of increase in F AlFI and, thus, the rate of induction of anesthesia (Stoelting: Pharmacology and Physiology in Anesthetic Practice, ed 2, pp 26-27).
Laminar flow in the airway occurs in the: (Select 2) A- trachea B- main stem bronchi C- terminal bronchiole D- 3rd generation bronchus E- respiratory bronchiole
E, C - terminal bronchiole, respiratory bronchiole Flow in the larger airways is mostly turbulent. Laminar flow normally occurs only distal to small bronchioles (< 1mm). The Reynolds number is used to predict the type of airway flow; a low Reynolds number (< 1000) is associated with laminar flow, whereas a high value (> 1500) is associated with turbulent flow.
All the following agents are acceptable for use in a Bier block EXCEPT A. 0.5% Lidocaine B. 0.5% Mepivacaine C. 0.5% Procaine D. 0.5% Prilocaine E. 0.25% Bupivacaine
E. 0.25% Bupivacaine Because of the potential for cardiotoxicity and because bupivacaine has no advantages over other local anesthetics in this setting, it is no longer recommended for use in intravenous regional anesthesia.
Hormones released by the neurohypophysis include: (Select 2) A-thryotropin B-growth hormone C-arginine vasopressin D-adrenocorticotropic hormone E-follicle stimulating hormone F-oxytocin G-prolactin H-luteinizing hormone
F-oxytocin, C-arginine vasopressin The neurohypophysis is another term for the posterior pituitary gland. The hormones of the neurohypophysis, oxytocin and arginine vasopressin (vasopressin, ADH), are synthesized in the hypothalamus and stored in the posterior pituitary. Stimulus for the release of arginine vasopressin arises from osmoreceptors in the hypothalamus that sense an increase in plasma osmolality.
Anesthetics that impair CBF autoregulation include (Choose all of the questions that are correct). I. Halothane, I MAC 2. Enflurane, I MAC 3. Isoflurane, I MAC 4. Thiopental, 4 mg/kg
I. Halothane, I MAC 2. Enflurane, I MAC 3. Isoflurane, I MAC Maintenance of a relatively constant cerebral blood flow despite changes in systemic mean arterial blood pressure is termed autoregulation. The upper and lower limits of autoregulation, in normotensive adult humans, are cerebral perfusion pressures of 150 and 50 mm Hg, respectively. Autoregulation appears to be impaired by volatile anesthetics. In contrast, nitrous oxide, barbiturates, and fentanyl do not appear to disturb autoregulation.
Match each appetite suppressant with its drug class. a. Orlistat 1. lipase inhibitor b. Sibutramine 2. NE & serotonin reuptake inhibitor c. Phentermine 3. Ephedra alkaloid d. Ma huang 4. NE reuptake inhibitor
Orlistat= lipase inhibitor Sibutramine= NE & serotonin reuptake inhibitor Phenteramine= NE reuptake inhibitor Ma huang= ephedra alkaloid
A 44-year-old 50-kg male received 750 mL of fresh frozen plasma. What percent of normal would you expect this clotting factor concentration to achieve post transfusion? (A) 100% (B) 75% (C) 60% (D) 30%
The initial therapeutic dose of fresh frozen plasma (FFP) is usually 10-15 mL/kg. The final goal of FFP administration is to achieve 30% of the normal coagulation factor concentration.
What is the storage life of RBCs stored with Adsol? A. 14 days B. 2 1 days C. 35 days D. 42 days E. 49 days.
There are many preservation solutions used for whole blood and RBCs. Acid citrate dextrose (ACD), CPD, and citrate phosphate double dextrose (CP2D) each allows blood to have a shelf life of 21 days. In 1978, the FDA approved the additive adenine to CPD. This extended the shelf life of blood by 2 weeks. CPDA-l has a shelf life of 35 days. These solutions were used mainly for whole blood. However, when component therapy became more widespread it was noted that packing the RBCs by removing the plasma removed a significant amount of adenine and glucose as well. By using an additive solution (which contains primarily adenine, glucose, and saline) to the CPD or CP2D whole blood that has the plasma removed, the "packed" RBCs can now be stored for 42 days. The three different additive solutions currently used in the United States are Adsol (AS-I), Nutricel (AS-3), and Optisol (AS-5)
Which of the following is true regarding phase II reactions. a- They produce conjugates that are polar and water soluble. b- They reduce the parent compound. c- They include reductive reactions. d- They are reactions that remove electrons from a molecule.
a- They produce conjugates that are polar and water soluble. Phase II reactions are the culmination of drug metabolism processes, whereby drug molecules that have been chemically altered by reduction, hydrolysis, or oxidation, are assimilated - conjugated - into compounds that are more easily removed from the body.
Which of the following drugs has the most potent amnesic effect? a- lorazepam b- midazolam c- flurazepam d- diazepam
a- lorazepam Lorazepam is the most potent amnesic agent. Providing AMNESIA for up to 6 hours.
You are called to the NICU to perform an anesthetic on a 3.5 kg neonate with congenital diaphragmatic hernia. The patient is intubated with conventional mechanical ventilation. The most recent arterial blood gas reveals a pH 7.38, PaCÓ 45 mmHg, PaÓ 89 mmHg, HCǑ 29 mEq/L, SaÓ of 97% on an FiÓ of 0.6. Peak airway pressures are 32 cmH2O with 5 cmH2O PEEP. Expiratory tidal volume is 45 ml. Which of the following is the MOST appropriate ventilatory management for this patient? a-Decrease peak airway pressure to 25 cmH2O b-Decrease FiÓ to 50% c-Increase FiÓ to 90% d-Increase PEEP to 7 cmH2O
a-Decrease peak airway pressure to 25 cmH2O Due to the concern of aggressive ventilation on both the short-term survival as well as long-term outcomes of congenital diaphragmatic hernia, ventilatory strategies that employ small tidal volumes with permissive hypercapnia have gained widespread acceptance. Boloker, et al. suggested preservation of spontaneous ventilation, acceptance of a pre-ductal oxygen saturation of 90-95% with >80% tolerated if the infant appears comfortable, permissive hypercapnia of 60-65 mmHg, and peak inspiratory pressures < 25 cm H20.
The potency of local anesthetics increases as the: a-lipid solubility increases b-pKa increases c-number of double bonds in the anesthetic molecule increases d-molecular weight decreases
a-lipid solubility increases Local anesthetic potency correlates directly with lipid solubility. In general, lipid solubility increases with an increase in the total number of carbon atoms in the molecule and by adding a halogen to the aromatic ring.
A nonselective α-antagonist used in the preoperative preparation of a patient with pheochromocytoma is: a-phenoxybenzamine b-doxazosin c-propranolol d-terazosin
a-phenoxybenzamine Phenoxybenzamine is a nonselective α-antagonist used in the preoperative preparation of the patient with pheochromocytoma. Doxazosin and terazosin are selective α1-antagonists. Propranolol is a nonselective β-antagonist. In the preparation of patients with pheochromocytoma, α-blockade and intravascular volume replacement must precede β-blockade, so as to prevent the possibility of unopposed α-stimulation.
OSA is a/w cessation of airflow for more than: a. 10 sec b. 5 sec c. 20 sec d. 25 sec
a. 10 sec
Which of the following suggest a increased risk of nerve injury during SSEP somatosensory monitoring? (Select 2) a. 10% increase in latency. b. 10% decrease in amplitude. c. 50% increase in latency. d. 50% decrease in amplitude.
a. 10% increase in latency. d. 50% decrease in amplitude. A 50% decrease in amplitude and a 10% increase in latency suggest the potential for neural injury.
The protein bound fraction of a drug decreases from 98% to 94%. What percent has the unbound fraction concentration increased? a. 4% b. 40% c. 100% d. 200%
a. 4%
Which statements regarding AChE drugs are true? (select 2) a. 50% of neostigmine is metabolized by liver b. Edrophonium + neostigmine has synergistic effect c. Renal failure necessitates a second dose d. Neostigmine is more potent than pyridostigmine
a. 50% of neostigmine is metabolized by liver d. Neostigmine is more potent than pyridostigmi -Mixing AChE yields an additive effect -RF prolongs DOA
What is the optimal tidal volume for a patient with class III obesity? a. 6-8ml/kg IBW b. 6-8ml/kg TBW c. 10-12ml/kg IBW d. 10-12ml/kg TBW
a. 6-8ml/kg IBW
Which statement regarding renal clearance is true? a. Basic urine enhances morphine reabsorption b. Organic anion transporters secrete drug into the distal convoluted tubule c. Protein bound drugs are filtered at the glomerulus d. Acidic urine promotes thiopental excretion
a. Basic urine enhances morphine reabsorption Morphine is a weak base. As a weak base, the unionized fraction increases in an alkalotic environment. Basic urine enhances morphine reabsorption. Thiopental is a weak acid. Acidic urine enhances its reabsorption (not excretion). Protein bound drugs do not feely pass through the glomerulus--only the free fraction is filtered. Organic anion transporters are present in the proximal (not distal) convoluted tubule. They actively secrete anions into the urine.
Which of the following are increased by succinylcholine administration? (select 2) a. LES tone b. risk of aspiration c. barrier pressure at gastroesophageal junction d. abdominal muscle tone
a. LES tone d. abdominal muscle tone
Which diagnosis is compatible with nasotracheal intubation? a. LeFort I fracture b. LeFort III fracture c. LeFort II fracture d. None of these are compatible with nasotracheal intubation
a. LeFort I fracture CI in LeFort II & III
Which bariatric procedures are more likely to cause nutritional deficiencies? (select 2) a. biliopancreatic diversion b. gastric sleeve c. gastric banding d. Roux-en-Y gastric bypass
a. biliopancreatic diversion d. Roux-en-Y gastric bypass
Which induction agent is contraindicated in the patient with acute intermittent porphyria? (select 2) a. thiopental b. midazolam c. ketamine d. etomidate
a. thiopental d. etomidate
Clearance is directly proportional to: (select 2) a. blood flow to clearing organ b. extraction ratio c. half life d. concentration in central compartment
a. blood flow to clearing organ b. extraction ratio Clearance is the volume of plasma that is cleared of a drug per unit of time. Cl is directly proportional to blood blow to the clearing organ, extraction ration, and drug dose. Cl is INVERSELY proportional to half life & drug concentration in the central compartment
A patient with an allergy to chloroprocaine can safely receive: (select 2) a. bupivacaine b. tetracaine c. dibucaine d. benzocaine
a. bupivacaine c. dibucaine
Which local anesthetics are most likely to produce methemoglobinemia? (select 3) a. cetacaine b. benzocaine c. ropivacaine d. mepivacaine e. etidocaine f. EMLA cream
a. cetacaine b. benzocaine f. EMLA cream Methemoglobin is formed when the iron on the hgb molecule becomes oxidized to its ferric form (Fe+3). It decreases O2 carrying capacity & shifts the oxyhemoglobin dissociation curve to the LEFT
Compared to the mainstream bronchi, which statements best describe the terminal bronchi? (select 2) a. cross sectional area is greater b. there is more cartilage c. there are more goblet cells d. airflow velocity is reduced
a. cross sectional area is greater d. airflow velocity is reduced
Central nervous system effects of etomidate include: (select 2) a. decreased ICP b. myoclonus c. analgesia d. cerebral vasodilation
a. decreased ICP b. myoclonus decreases CBF (cerebral vasoconstriction) no analgesia
Pathophysiologic complications r/t chronic HTN include all of the following except: a. decreased diastolic filling time b. increased myocardial oxygen consumption c. dysrhythmias d. left ventricular hypertrophy
a. decreased diastolic filling time HTN increases afterload. The LV must generate a higher amount of wall tension in order to open the AV. In chronic HTN, the LV remodels concentrically because a greater mass augments the heart's ability to perform work. The problem is that more tissue means a higher need for oxygen (MVÓ). Additionally, a thicker heart suffers from reduced compliance & diastolic dysfunction (decreased lusitropy) is a downstream consequence of this. There is a tipping point where the heart requires more Ó than what is delivered; this is when pt is at greatest risk for dysrhythmias or CHF Diastolic filling time is determined by HR.
Which of the following are associated with obesity? (select 3) a. increased renal clearance b. decreased Vd of lipid soluble drugs c. increased total body water d. increased blood volume e. decreased lean body weight f. increased cardiac output
a. increased renal clearance d. increased blood volume f. increased cardiac output
Modern theory of anesthetic action suggests inhaled anesthetics: (select 2) a. interact with stereoselective receptors b. produce immobility by binding in the dorsal horn of the spinal cord c. stimulate the NMDA receptor d. facilitate GABA transmission
a. interact with stereoselective receptors d. facilitate GABA transmission volatile anesthetics most likely exert their effects by stimulating & inhibiting a variety of stereoselective receptors & not simply by disrupting the integrity of the phospholipid bilayer. The primary target of halogenated anesthetics in the brian is facilitation of the GABA-A receptor. Primary target of volatile ansethetics in the SC is stimulation of glycine channels & inhibition (not stimulation) of NMDA receptors & Na channels. Volatile anesthetics produce immobility in the ventral horn of the SC (not dorsal).
Choose the statements that demonstrate an accurate understanding of thiopental (select 2). a. it causes a reflex tachycardia b. there is a sulfur molecule in the second position c. prompt awakening is the result of hepatic metabolism d. it provides neuroprotection against global ischemia
a. it causes a reflex tachycardia b. there is a sulfur molecule in the second position Thiobarbiturate with sulfur molecule in the 2nd position. HoTN is primarily the results of venodilation & decreased preload. Myocardial depression is a secondary cause. Baroreceptor reflex remains intact, there is a reflex tachycardia. This explains why thiopental tends to cause less HoTN compared to propofol (propofol impairs the baroreceptor reflex) Metabolized by hepatic is metabolized by P450 enzymes, rapid awaking following a single IV induction dose is result of redistribution out of the brain (not metabolism). Thiopental can reduce CMRO2 by producing an isoelectric EEG. May confer neuroprotection against focal ischemia, but there is not strong evidence that it protects the brain during global ischemia
Pick the statements that most accurately describe an intra-aortic balloon pump (select 2) a. it inflates during diastole & increases myocardial oxygen supply b. the tip of the balloon should be positioned 2cm proximal to the brachiocephalic artery c. it is contraindicated in severe AI d. it inflates during systole & reduces after load
a. it inflates during diastole & increases myocardial oxygen supply c. it is contraindicated in severe AI IABP improves myocardial oxygen supply while reducing demand. Inflates during diastole & increases coronary perfusion pressure (increase supply). It deflates during systole & reduces after load (decrease demand) Tip of balloon positioned 2cm distal to left subclavian artery. more proximal position causes balloon to occlude perfusion of the left common carotid &/or brachiocephalic arteries.
Fospropofol is: (select 2) a. metabolized by alkaline phosphatase b. associated with pain at the injection site c. a prodrug d. prepared as a lipid emulsion
a. metabolized by alkaline phosphatase c. a prodrug Prodrug metabolized to propofol in systemic circulation. Alkaline phosphatase is the enzyme that carries out the rxn. Bc the drug is activated inside the body, it has a prolonged onset and longer DOA. It is prepared in an aqueous solution & is not a/w pain at injection. Can cause burning in genital/anal regions.
Which valvular disorders are associated with a systolic murmur? (select 2). a. mitral insufficiency. b. aortic stenosis. c. mitral stenosis. d. aortic insufficiency.
a. mitral insufficieny b. aortic stenosis murmur is caused by turbulent blood flow. -blood become turbulent as it passes thru a tight AV during ejection phase of systole. -issue during isovolumetric contraction during systole. AR issue during iso volumetric relaxation of LV during diastole MS issue during atrial systole (atrial kick) occurring during diastole.
All of the following drugs improve biliary HTN except: a. octreotide b. nitroglycerin c. naloxone d. glucagon
a. octreotide (somatostatin analogue- increase) -contraction of sphincter of Oddi can increase biliary pressure causing biliary colic, false positive cholangiogram -relax sphincter: glucagon, glyco, atropine, naloxone, nitro
Which substrates induce hepatic P450 enzymes? (select 2) a. phenytoin b. cimetidine c. erythromycin d. tobacco smoke
a. phenytoin d. tobacco smoke
Which characteristics correlate best with local anesthetic duration of action? a. protein binding b. lipid solubility c. pKa d. concentration
a. protein binding Onset= pKa Potency= Lipid solubility Duration= Protein binding
When compared to T4, which statement best describes T3? (select 2) a. shorter half life b. more protein bound c. higher potency d. higher concentration in blood
a. shorter half life c. higher potency T4- more protein bound, higher concentration
Which NMBA is a/w the highest incidence of anaphylaxis? a. succinylcholine b. atracurium c. pancuronium d. vecuronium
a. succinylcholine
Select the drug whose initial dose should be based on total body weight. (select 2) a. succinylcholine b. remifentanil c. midazolam d. propofol
a. succinylcholine c. midazolam -remifentanil & propfol- LBW
Identify the statement that most accurately describes the patient with an abdominal aortic aneurysm (select 2) a. surgical intervention is recommended when the diameter is > 5.5cm b. back pain and hypotension suggest rupture c. risk of aneurysmal rupture is best described by Poiseuille's law d. it is more common in females
a. surgical intervention is recommended when the diameter is > 5.5cm b. back pain and hypotension suggest rupture Law of Laplace states that increased diameter increases wall tension. Independent RF include cigarette smoking, male > female, advanced age.
Compared to scopolamine, atropine is more likely to produce: a. tachycardia b. cycloplegia c. xerostomia d. sedation
a. tachycardia
Which kinetic model describes the process that metabolizes a constant amount of drug per unit time? a. zero order b. first order c. second order d. third order
a. zero order first order describes situation where a constant fraction of the drug is metabolized per unit time.
Drugs that are incapable of producing a maximal effect even at very high concentrations are called which of the following? a- agonist b- partial agonist c- competitive agonist d- antagonist
b- partial agonist Drugs that bind to a specific receptor but produce only a limited response, no matter the drug concentration, are termed partial agonist.
______________ effects most likely occur when drugs with identical mechanisms are combined. a- Antagonistic b- Additive c- Synergistic d- Additive and synergistic
b- Additive Additive effects are seen when two drugs that have the same or very similar mechanisms of action are administered and the effects observed are greater than the combined effects of the two individual drug.
Which of the following are safe to adminster to a patient with acute intermittent porphyria ? (select 2) a- etomidate b- succinylcholine c- methohexital d- nitrous oxide
b- succinylcholine d- nitrous oxide Avoid all barbituates as well as etomidate.
Which of the following drugs is included in Step 1 in the World Health Organization (WHO) analgesic ladder? a-Codeine b-Ketoprofen c-Propoxyphene d-0Tramadol
b-Ketoprofen The World Health Organization (WHO) analgesic ladder was established in 1986 to guide physicians developing treatment plans for cancer pain. In general terms, Step 1 includes Non-opioid analgesics, with or without adjuvants. Step 2 includes "weak" opioids (such as codeine, propoxyphene, and tramadol), with or without adjuvants. Step 3 includes "strong" opioids (such as morphine, fentanyl, and methadone) and non-opioids, without or without adjuvants. Ketoprofen is the only non-opioid listed.
A pulmonary function test for a patient with COPD or emphysema might show which of the following? a. FEV1> 70% b. FEV1/FVC < 80 % of predicted value c. Decreased residual volume d. Decreased functional residual capacity
b. FEV1/FVC < 80 % of predicted value.
What is the blood: gas partition coefficient of nitrogen? a. 0.14 b. 0.014 c. 0.0014 d. 0.00014
b. 0.014 Nitrous oxide is 34x more soluble than nitrogen and the B:G partition coefficient of N2O is 0.46. 0.46/34= 0.014
Which of the following apnea/hypoapnea index scores is consistent with mild obstructive apnea? a. 3 b. 12 c. 25 d. 40
b. 12
What percentage of the CO is delivered to the muscle & skin? a. 10% b. 20% c. 50% d. 75%
b. 20% vessel rich-75%
During a constant infusion, plasma steady-state drug concentration reaches 90% half-lives a- 2.1 b. 3.3 c. 7.9 d. 10.2
b. 3.3 A steady state is achieved when the quantity of a drug administered is equal to the quantity of drug that is eliminated via metabolism, etc. This process requires time to achieve; the length of time is determined by the half-life of the drug. For continuous infustions, 3.3 half-lives are required to achieve this equilibrium.
For every 1 molecule of nitrogen that exits the middle ear, how many molecules of N2O enter to take its place a. 25 b. 34 c. 40 d. 52
b. 34
The maximum percentage of nicotinic receptors occupied during a 5 second head lift is: a. 25% b. 50% c. 75% d. 90%
b. 50%
What is the estimated blood volume for a patient with class III obesity? a. 40ml/kg b. 50ml/kg c. 60ml/kg d. 70ml/kg
b. 50ml/kg
Which statement best describes the pathway of blood through the kidney? a. Afferent arteriole>efferent arteriole>glomerular capillary bed>peritubular capillary bed b. Afferent arteriole > glomerular capillary bed > efferent arteriole >peritubular capillary bed c. Glomerulus > proximal tubule > loop of henle > distal tubule > collecting duct d. Glomerular capillary bed > afferent arteriole > peritubular capillary bed > efferent arteriole
b. Afferent arteriole > glomerular capillary bed > efferent arteriole >peritubular capillary bed
Which statement best describes the pathway of blood through the kidney? a. Afferent arteriole>efferent arteriole>glomerular capillary bed>peritubular capillary bed b. Afferent arteriole > glomerular capillary bed > efferent arteriole >peritubular capillary bed c. Glomerulus > proximal tubule > loop of henle > distal tubule > collecting duct d. Glomerular capillary bed > afferent arteriole > peritubular capillary bed > efferent arteriole
b. Afferent arteriole > glomerular capillary bed > efferent arteriole >peritubular capillary bed
Identify the drugs that are metabolized by nonspecific plasma esterases. (select 3) a. Succinylcholine b. Atracurium c. Esmolol d. Cocaine e. Remifentanil f. Fospropofol
b. Atracurium c. Esmolol e. Remifentanil Enzymatic drug metabolism in the plasma tends to occur via 1 of 3 pathways: Pseudocholinesterase: succinylcholine, cocaine (+hepatic) Nonspecific esterases: escollo, remifentanil, atracurium (+ hofmann) Alkaline phosphate: fospropofol Hofmann elimination also takes place in the plasma, but is dependent on pH and temperature (not enzymatic fxn)
A patient states she experienced HoTN, tachycardia, & shortness of breath after receiving tetracaine during a previous surgery. Which of the following drugs should be avoided in this patient? (select 3) a. Mepivacaine b. Cocaine c. Chloroprocaine d. EMLA cream e. Benzocaine f. Articaine
b. Cocaine c. Chloroprocaine e. Benzocaine There is no cross sensitivity between these classes (esters & amides). Since the preservatives are often the cause of an alleged allergic reaction, a preservative free anesthetic should be selected.
After suffering a MI, a patient presents with a LV papillary muscle rupture & MR. Which of the following will worsen this patient's condition? (select 3) a. Increased HR b. Decreased HR c. Increased SVR d. Decreased SVR e. Increased LV to LA pressure gradient f. Decreased LV to LA pressure gradient
b. Decreased HR c. Increased SVR e. Increased LV to LA pressure gradient The anesthetic goals for MR are full, fast, forward. The idea is to minimize regurgitant volume (the art of blood that travels thru the MV during LV systole) The regurgitant volume is made worse by bradycardia, an increased LV to LA pressure gradient, and increased SVR
What drug inhibits codeine metabolism? a. Phenytoin b. Fluoxetine c. Diltiazem d. Rifampin
b. Fluoxetine Codeine is biotransformed to its active metabolite (morphine) by CYP 2D6. The Cp of its active metabolite is affected by alterations in CYP 2D6 activity. Quinidine & SSRI (fluoxetine & paroxetine) profoundly inhibit CYP 2D6. Codeine, oxycodone, & hydrocodone will not be effectively metabolized to morphine & will fail to provide adequate pain relief. The clinical correlation is that these analgesics are poor choices for pts. taking SSRIs or quinidine.
Which conditions impair myocardial contractility? (select 3) a. Hypovolemia b. Hypoxia c. Hypercalcemia d. Hypocapnia e. Hypercapnia f. Hyperkalemia
b. Hypoxia e. Hypercapnia f. Hyperkalemia contractility is the ability of the myocardial sarcomeres to perform work (shorten & produce force). It is independent of preload & after load. Hypoxia & acidosis impair contractility. In absence of Ó, the cardiac myocytes convert to anaerobic metabolism. In this situation, intracellular lactate increases leading to acidosis & impaired enzymatic function. The net result is decreased contractility. Hypercapnia is the result of accumulation of volatile acids. Again acidosis impairs contractility. Hyperkalemia increases RMP. Voltage gated Na channels fire in response to depolarization, but they can't fire again until cell has depolarized. IF RMP rises to level that exceeds where these channels would otherwise depolarize, they'll get stuck in closed & inactive state. Myocyte can't be depolarized & can't contract.
Select the statements that best describe constrictive pericarditis (Select 2). a. it is most commonly caused by a virus b. Kussmaul's sign is usually present c. after load should be reduced d. bradycardia should be avoided
b. Kussmaul's sign is usually present d. bradycardia should be avoided constrictive pericarditis limits the heart's ability to move within the pericardial sac. This reduces myocardial compliance & limits diastolic filling. Kussmaul's sign is a paradoxical rise in CVP & jugular venous dissension during inspiration. Its the result of the RV filling defect--impaired RV compliance. SV is reduced, CO must be maintained w/ an adequate HR. Avoid bradycardia. BP= CO x SVR. If CO is limited, the BP must be maintained by SVR. Do not reduce after load. Acute pericarditis is usually caused by a virus.
Which of the following increases renin release? a. increased Cl delivery to the macula densa b. PEEP c. Hypervolemia d. Angiotensinogen
b. PEEP Renin release is increased by 3 things: -reduced renal perfusion -b-1 activation -decreased Na & Cl delivery to the distal tubule PEEP reduces venous return & may reduce CO. By extension, this reduces renal perfusion & stimulates renin release
A patient with chronic respiratory acidosis secondary to COPD is dependant upon what to continue breathing? a. Low arterial pH. b. Peripheral chemoreceptors c. FEV1 of less than 50% d. Ventilation and perfusion mismatch.
b. Peripheral chemoreceptors
Regarding the modern halogenated anesthetics in the adult at 1MAC: a. heart rate decreases b. QT interval increases c. mean arterial blood pressure increases d. systemic vascular resistance increases
b. QT interval increases increase the duration of myocardial repolarization by impairing an inward K+ current. This prolongs QT interval. HR increases (des/iso), stays the same (sevo) vasodilation causes a reduction in SVR MAP decreases
Proof of anaphylaxis can be provide by immediately obtaining which lab value or test? a. Serum mast cell level b. Serum tryptase level c. Skin testing d. Radioallergosorbent test
b. Serum tryptase level Tryptase is stored in mast cells, an integral immune system compoent, and released into the systemic circulation when anapylaxis occurs but not during an anaphylactoid reaction. Significant increases in serum tryptase is detectable within 60-120 mins of an anaphylactic reaction.
Which statement regarding renal clearance is true? a. basic drugs are better absorbed in acidic urine b. acidic drugs are better excreted in basic urine c. acetazolamide encourages reabsorption of acidic drugs d. cranberry juice facilitates elimination of acidic drugs
b. acidic drugs are better excreted in basic urine basic drugs are better absorbed in a basic medium acetazolamde alkalizes urine and helps eliminate acidic drugs cranberry juice acidifies urine and helps eliminate basic drugs
Causes of coronary vasodilation include: (select 2) a. alpha-1 stimulation b. adenosine c. beta-2 stimulation d. hypocapnia
b. adenosine c. beta-2 stimulation Alpha-1 & hypocapnia cause coronary vasoconstriction.
Desflurane affects somatosensory evoked potentials by: a. decreasing amplitude & decreasing latency b. decreasing amplitude & increasing latency c. increasing amplitude & decreasing latency d. increasing amplitude & increasing latency
b. decreasing amplitude & increasing latency
Which agent impairs the hypoxic ventilatory response the LEAST? a. sevoflurane b. desflurane c. isoflurane d. These drugs all produce similar degrees of depression
b. desflurane all anesthetics suppress the hypoxic ventilatory response, DES is least.
Propofol infusion syndrome is categorized by the presence of: (select 2) a. hypokalemia b. metabolic acidosis c. bradycardia d. respiratory failure
b. metabolic acidosis c. bradycardia propofol contains long chain triglycerides, and an increased LCT load impairs oxidative phosphorylation & fatty acid metabolism. This starves cells of oxygen, particularly in cardiac & skeletal muscle. Propofol infusion syndrome presents with acute refractory bradycardia --> systole + at least one of the following: - metabolic acidosis (base deficit > 10 mmol/L) - Rhabdomyolysis
C-fibers mediate: (select 2) a. skeletal m. tone b. non-discriminative touch c. proprioception d. pain
b. non-discriminative touch d. pain
Which insulin preparation can be administered intravenously? a. very rapid acting b. rapid acting c. intermediate acting d. long acting
b. rapid acting
Primary treatment of anaphylaxis should include which of the following? a- copious amounts of IV fluids and epinepherine. b- corticosteroids, antihistamines, and IV fluids. c- Airway support, 100% oxygen, stopping all drugs, IV fluids, and epinepherine. d- Bronchodilators, corticosteroids, sodium bicarbonate, vasopressin, epinepherine.
c- Airway support, 100% oxygen, stopping all drugs, IV fluids, and epinepherine. The first and foremost concern during anaphylaxis is maintenance of the patient's airway. Oxygenation must be maximized by provision of 100% oxygen. All drugs must be removed as quickly as possible because the offending drug may not be readily apparent. Hypotension due to global vasodilation must be countered with the administration of both IVF and epinepherine .
Choose the incorrect statement. a.) Lipophilic drugs have greater volumes of distribution than hydrophilic drugs. b- The efficiciency of the body to remove a drug from itself is proportional to the elimination clearance. c- Dose response curves are able to determine variation in pharmacological response cause by pharmacodynamics. d- Renal elimination of lipophilic compounds is negligible.
c- Dose response curves are able to determine variation in pharmacological response cause by pharmacodynamics. [ Dose- response cuves depict the response observed to a quantity of a drug- the dose administered; it is not capable of determining or measuring whether response of pharmacokinetics and/or pharmacodynamics].
Chronically denervated neuromuscular junctions will _____________ the specific receptors in an attempt to produce a signal in the face of lower concentrations of agonist. a- Down-regulate b- Change the morphology of c- Up-regulate d- Signal a second messenger to activate
c- Upregulate Prolonged exposure of receptors leads to a diminution of the effect of a drug at the target site. Similarly, an extended period of receptor inactivity results in production of a relative maximal or super-maximal effect at the receptor.
An otherwise healthy 45-year-old woman is seen at an ambulatory surgical center for release of Dupuytren's contracture. A brachial plexus block is performed using the axillary approach. Assuming that no other nerve blocks are performed, and that the axillary block successfully achieves a complete motor and sensory block in its intended distribution, which of the following motor responses in the blocked extremity would MOST likely still be present? a-Wrist flexion b-1st-5th digit adduction c-Forearm supination d-Extension of the MCP joints
c-Forearm supination At the level of the axillary artery, the brachial plexus has divided into three cords (medial, lateral, and posterior), which are named in relationship to the axillary artery. These three cords travel with the axillary artery within the axillary sheath. The musculocutaneous nerve, however, as a terminal branch of the lateral cord, travels separately and is NOT located inside the axillary sheath. Thus, it must be blocked separately from an axillary brachial plexus block. Assuming that a musculocutaneous nerve block has not been performed, we would not expect to see a motor block of the biceps muscle, and elbow flexion and forearm supination, as well as cutaneous sensation to the lateral forearm, would be intact.
Which of the following is LEAST likely to be a contraindication to left ventricular assist device (LVAD) placement? a-An atrial septal defect b-Severe aortic insufficiency c-Severe mitral regurgitation d-Severe mitral stenosis
c-Severe mitral regurgitation This is a challenging question that few people answer correctly! Most anesthesiologists do not know contraindications to left ventricular assist device (LVAD) placement. Placement of an left ventricular assist device (LVAD) improves forward flow and typically reduces mitral regurgitation; therefore, this is not a contraindication to placement. Severe mitral stenosis must be corrected as it is an impediment to flow into the LVAD's inflow cannula. An atrial septal defect (or significant PFO) could result in right to left shunting and hypoxemia. Severe aortic regurgitation would cause most of the flow out of the LVAD's outflow cannula to go back into the left ventricle instead of systemically.
The postretrobulbar block apnea syndrome: a-is likely secondary to intravascular injection b-most commonly occurs during or immediately after injection c-is associated with unconsciousness d-carries a high morbidity and mortality
c-is associated with unconsciousness The postretrobulbar block apnea syndrome is probably due to injection of local anesthetic into the optic nerve sheath, with spread into the CSF. The CNS is exposed to high concentrations of local anesthetic leading to apprehension and unconsciousness. Apnea occurs within 20 minutes and resolves within an hour. Treatment is supportive.
What dibucaine number is consistent with heterozygous pseudocholinesterase? a. 20 b. 40 c. 60 d. 80
c. 60
Which patient exhibits the greatest number of risk factors for difficult mask ventilation? a. 40 year old obese male with h/o snoring b. 4 year old female with reduced cervical mobility & h/o asthma c. 70 year old edentulous male with a beard d. 25 year old female with a small mouth opening and a prominent overbite
c. 70 year old edentulous male with a beard B=beard, O=obese, N=no teeth, E=elderly, S=snoring
What is the maximum allowable dose for mepivcaine? a. 2mg/kg b. 5mg/kg c. 7mg/kg d. 10mg/kg
c. 7mg/kg
How many calories are required to produce 1 g of body fat? a. 4 b. 7 c. 9 d. 11
c. 9 -if unused, body will store as adipose - 1 g of carbohydrate= 4 cal - 1 g of protein= 4 cal
Which of the disease are a/w hyperkalemia following succinylcholine administration (select 2) a. myotonic dystrophy b. ALS c. Charcot-Marie-Tooth d. Myasthenia gravis
c. Charcot-Marie-Tooth b. ALS
Which process is a phase 2 reaction? a. Hydrolysis b. Reduction c. Conjugation d. Oxidation
c. Conjugation Phase 1: Modification (oxidation, reduction, hydrolysis) Phase 2: conjugation Phase 3: excretion
Anesthetic considerations for the patient with diabetes insipidus include: a. sodium restriction b. 3% sodium chloride c. DDAVP d. demeclocycline
c. DDAVP SIADH= 3% NaCl & demeclocycline, fluid restriction
A patient with adrenal insufficiency & sepsis requires an emergency intubation in the intensive care unit. Which of the following drugs should be avoided? a. Thiopental b. Propofol c. Etomidate d. Ketamine
c. Etomidate
Which of the following is true of a pharmacodynamic interaction? a. Its a chemical or physical interaction that occurs after a drug is administered or adsorbed systemically. b. It occurs when one drug alters the absorption, distribution, metabolism, or elimination of another. c. It occurs when one drug alters the sensitivity of a target receptor or tissue to the effects of a second drug. d. None of the above
c. It occurs when one drug alters the sensitivity of a target receptor or tissue to the effects of a second drug. Pharmacokinetics reactions are those in which one drug alters or affects the absorption, distribution, metabolism, or elimination of another drug. A pharmacodynamic reaction occurs when one drug impacts or affects the sensitivity of a receptor or tissue to the effects of a second drug.
Which of the following is responsible for removing bacteria from the liver? a. canaliculi b. Acinus c. Kupffer cells d. sinusoids
c. Kupffer cells acinus= function unit of liver sinusoids= contain larger pore to permit passage of large molecules; kupffer cells located here canaliculi= collect bile produced by hepatocytes
In the obese patient, how much does FRC decrease in the supine position after induction of anesthesia? a. 20% b. 30% c. 40% d. 50%
d. 50%
Which two leads of the electrocardiogram provide a sensitivity of 80% for the detection of myocardial ischemia? a. Leads I and II b. Leads I and V5 c. Leads II and V5 d. Leads II and V3 e. None of the above
c. Leads II and V5
Which nerve serves as the afferent limb of the laryngospasm reflex? a. SLN external branch b. glossopharyngeal c. SLN internal branch d. RLN
c. SLN internal branch SLN external branch= efferent limb glossopharyngeal= afferent of gag reflex
All of the structures reside in the renal cortex except: a. proximal tubule b. glomerulus c. collecting duct d. distal tubule
c. collecting duct The nephron consists of 5 major components: glomerulus, proximal tubule, loop of henle, distal tubule & collecting duct. Cortex(outer region): golmeruli, proximal tubules, distal tubules Medulla(inner region): loops of henle, collecting ducts
All of the structures reside in the renal cortex except: a. proximal tubule b. glomerulus c. collecting duct d. distal tubule
c. collecting duct The nephron consists of 5 major components: glomerulus, proximal tubule, loop of henle, distal tubule & collecting duct. Cortex(outer region): golmeruli, proximal tubules, distal tubules Medulla(inner region): loops of henle, collecting ducts
A patient with untreated hyperthyroidism & atrial fibrillation presents for emergency surgery. What is the best intervention at this time? a. amiodarone b. propylthiouracil c. esmolol d. delay surgery until a euthyroid state is achieved
c. esmolol
Which of the following requires energy that is most provided by the hydrolysis of ATP? a- facilitated diffusion b- passive transport c-elimination clearance d- active transport
d- active transport [Active transport of any substance across a cellular membrane consumes a considerable amount of energy. This energy is typically performed by the hydrolysis of adenosine triphosphate (ATP) ] .
Hepatic drug clearance depends on which of the following? a- Hepatic blood flow b- Extent of binding of the drug to blood components c- Intrinsic ability of the liver to metabolize the drug. d. All of the above
d- all of the above [Drug metabolism is most often accomplished by the liver and is thus dependent on a multitude of factors including hepatic blood flow, binding to blood components, the health of the liver- its intrinsic ability to metabolize a drug and others.
Which of the following is responsible for the most intraoperative anaphylactic reactions? a- latex b- protamine c- antibiotics d- muscle relaxants
d- muscle relaxants Contrary to popular belief or conventional thought, it is not antibiotics to which most anaphylactic reactions may be attributed intraoperatively; the mjority occur in response to the administration of muscle relaxants.
An inducer of hepatic drug metabolism includes which of the following? a- calcium channel blockers b- cimetidine c- antidepressants d- phenytoin
d- phenytoin The main metabolic pathway, the cytochrome p450 system, may be inhibited or excite by various drugs; phenytoin is one such drug that cause excitement or induction of these metabolic enzymes in the liver.
A 68-year-old man undergoes right colectomy for colorectal cancer. He had been taking clopidogrel, which was held for one week prior to surgery. Intraoperatively he is transfused one unit of PRBCs and one unit of platelets. On post-operative day 3, his hemoglobin drops from 10 to 8.2 mg/dL. He is hemodynamically stable and only complains of mild back pain. He is transfused 1 unit of PRBCs and follow-up Hgb is 8.4 mg/dL. What is the MOST likely cause for his anemia? a-Dilution of blood by maintenance IV fluids b-Inadequate surgical hemostasis exacerbated by preoperative clopidogrel c-Carcinoma-induced coagulopathy d-Immune-mediated reaction.
d-Immune-mediated reaction. This patient most likely has a delayed antibody-mediated hemolytic transfusion reaction from the PRBCs given during his surgery. Hemolysis is the most likely cause for the patient's anemia at this time due to lack of signs suggestive of acute blood loss. Such reactions can occur 3-21 days post-transfusion. Laboratory values such as elevated unconjugated bilirubin help lend evidence to this mechanism for his anemia.
All of he following may be seen in patients experiencing pulmonary embolism except a. decreased PetCÓ b. Increased PaCÓ c. Increased pulmonary artery pressures d. Incomplete or complete Left BBB.
d. Incomplete or complete Left BBB.
Assuming that the functional residual capacity remains constant, which of the following explains a temporary increase in alveolar oxygen concentration when nitrous oxide is turned on during an inhalation induction? a. Ventilation effect b. Diffusion hypoxia c. Concentration effect d. Second gas effect
d. Second gas effect Nitrous oxide hastens the onset of a second gas, but it explains why alveolar oxygen might transiently increase. FRC may become smaller during anesthetic induction with a halogenated agent, so in clinical practice the PaÓ may not always increase.
Determinants of drug tissue uptake include which of the following? a. blood flow b. blood-brain barrier c. ionization d. all of the above.
d. all of the above Uptake of a drug by a targeted tissue is dependent on several factors, both physical and chemical, including circulation or blood flow, the characteristics of the bbb toward that specific drug, the chemical properties of that drug - such as the degree of ionization, lipid solubility, and protein binding, among others.
Which subunits must be occupied to open the nicotinic receptor at the motor end plate? a. alpha &gamma b. alpha & epsilon c. alpha & delta d. alpha & alpha
d. alpha & alpha The postsynaptic nicotinic receptor Nm is a pentameric ligand-gated ion channel located in motor endplate at NMJ. 5 subunits that align circumferentially around ion conducting pore. 2 alpa subunits on receptor and both must be occupied by an agonist (ACh or succ) for channel to open
Which food corresponds with the most pathologic form of fat accumulation? a. watermelon b. carrot c. pear d. apple
d. apple android obesity- apple gynecoid obesity- pear
Sevoflurane at 1.5 MAC increases: a. cerebrospinal fluid production b. cerebral vascular resistance c. cerebral metabolic rate of oxygen d. cerebral blood volume
d. cerebral blood volume Volatiles uncouple metabolism from CBF. They supply the brain with more BF than it needs. Since more blood is delivered to the brain per minute, the CBV increases. CMRO2 is decreased, CVR is decreased, CSF production decreases
Which local anesthetics undergoes the smallest degree of plasma protein binding? a. ropivacaine b. lidocaine c. benzocaine d. chloroprocaine
d. chloroprocaine
Which NMBA is most likely to cause anaphylaxis? a. cisatracurium b. rocuronium c. atracurium d. succinylcholine
d. succinylcholine