Prodigy - Missed Questions - Week 1 Assignment
What dermatome is innervated by C5?
The 5th cervical spinal nerve (C5) provides sensory innervation to the lateral aspect of the arm just proximal to the elbow.
What is the Coanda effect?
The Coanda effect describes the predisposition for a fluid or gas to follow a curved path at the bifurcation point of a tube. As the cross-sectional area of the tubes increases, the velocity of the gas or fluid decreases and the pressure increases. The tube in which the pressure increases last tends to receive a greater distribution of the gas or fluid. This effect can be of consequence in blood vessels or in the pulmonary airways where blood or oxygen preferentially flows to one area over another.
What is the appropriate initial dose of dantrolene in milligrams to treat malignant hyperthermia in a 70 kg patient? (Provide your answer as the nearest whole number)
The correct answer is 175. Treatment of acute episodes of malignant hyperthermia is 2.5 mg/kg IV every 5-10 minutes. The initial dose for this patient would be 175 mg. Even if the episode is under control, dantrolene may have to be repeated at a dose of 1-2 mg/kg every 6 hours for a 24 hour period to prevent recurrence.
An E-cylinder oxygen tank pressure gauge reads 950 psig. How much oxygen is left in the tank? Provide your answer in liters to the nearest whole number.
The correct answer is 330. A full E-cylinder oxygen tank holds 660 liters at a pressure of 1900 psig. Because an oxygen tank's pressure is proportional to its contents, if the pressure falls by half, then the number of liters falls by half as well.
Which of the following would be most likely to exhibit a more intense effect in a patient with renal failure? A. A single dose of midazolam B. A single dose of morphine C. A single dose of cisatracurium D. A single dose of ketamine
The correct answer is A. Benzodiazepines are extensively protein bound. The reduced protein binding in patients with renal disease results in an increased free fraction of the drug. Also, 60-80% of midazolam is excreted as an active metabolite. In renal disease, this metabolite accumulates and can result in prolonged sedation. Single doses of ketamine and cisatracurium do not exhibit significant alteration in intensity or duration in patients with renal dysfunction. A single dose of morphine demonstrates no significant prolongation of effect in patients with renal disease. With repeated dosing or infusion, however, morphine's active metabolite, morphine-6 glucuronide, accumulates and can result in prolonged narcosis.
Which electrolyte disorder is most strongly associated with cirrhosis? A. Hyponatremia B. Hyperkalemia C. Hyperglycemia D. Hyperphosphatemia
The correct answer is A. Cirrhosis is associated with hyponatremia, anemia, thrombocytopenia, hyperbilirubinemia, and hypoalbuminemia.
Which of the following would be the least likely cause of transient dysrhythmias in the postanesthesia care unit? A. Myocardial ischemia B. Hypercarbia C. Hypokalemia D. Excess fluid administration
The correct answer is A. Hypercarbia, hypokalemia, hypoxia, excess fluid administration, substance withdrawal, and acid-base disturbances are capable of producing transient dysrhythmias after anesthesia. Most often, the cause is not myocardial injury.
A patient about to undergo an above-the-knee amputation asks you when phantom pain would begin if it occurs. You should inform him that the onset is typically A. within a few days postoperatively B. within a few weeks postoperatively C. within a few months postoperatively D. within a few years postoperatively
The correct answer is A. It may present immediately, but phantom pain usually occurs within a few days of the amputation.
Nonimmune anaphylactic reactions are the result of A. mediator release from mast cells B. mediation by IgA antibodies C. mediation by IgG antibodies D. mediation by IgE antibodies
The correct answer is A. Nonimmune anaphylactic (formerly known as anaphylactoid) reactions differ from anaphylactic reactions in that they do not involve IgE antibodies, but are instead mediated by mast cell and basophil activation.
Which of the following drugs will increase intraocular pressure? A. Succinylcholine B. Fentanyl C. Nitrous oxide D. Benzodiazepines
The correct answer is A. Succinylcholine can increase intraocular pressure (IOP). Nondepolarizing agents either decrease the IOP or have no effect on it. Volatile anesthetics, nitrous oxide, opioids, benzodiazepines, and barbiturates all decrease the IOP.
What nerve provides sensory innervation to the airway between the epiglottis and the vocal cords? A. Internal branch of the superior laryngeal nerve B. External branch of the superior laryngeal nerve C. Recurrent laryngeal nerve D. Glossopharyngeal nerve
The correct answer is A. The airway between the epiglottis and the vocal cords derives sensory innervation from the internal branch of the superior laryngeal nerve. The external branch of the superior laryngeal nerve is motor only and innervates the cricothyroid muscle.
What is the principal byproduct of deamination of amino acids? A. ammonia B. glycine C. albumin D. carbon dioxide
The correct answer is A. The liver is capable of producing up to 50 grams of protein a day. It is also responsible for the deamination of amino acids into carbohydrates and fats for energy. Ammonia is produced as a byproduct of deamination. The liver converts ammonia into urea. In the presence of liver failure, the levels of serum proteins and clotting factors will decrease and ammonia levels will increase.
Which of the following will increase the amount of tidal volume lost during inspiration due to wasted ventilation? A. Increases in airway pressure B. Decreased breathing system volume (a smaller breathing circuit) C. Decreased circuit compliance D. Increased respiratory rate
The correct answer is A. Wasted ventilation is a reduction in the tidal volume delivered to the patient due to distention of the breathing system components. The tidal volume lost increases with increased airway pressures, increased tidal volume, increased compliance of the breathing system components, and increased breathing system volume.
You are preparing to perform a retrobulbar block with an injection along the infratemporal wall of the orbit. You direct the patient to look A. up and toward the nose B. down and toward the nose C. up and away from the nose D. down and away from the nose
The correct answer is A. When performing a retrobulbar block, the needle is inserted along the infratemporal wall of the orbit. The patient should be instructed to look supranasally (slightly upward and toward the nose) as the needle is inserted 1.5 cm. It is then directed upward toward the apex of the orbit until it pierces the muscle cone.
Which of the following are factors that are associated with an increased risk of postoperative blindness in a prone patient? (select four) A. Obesity B. Male gender C. Greater than 500 mL blood loss D. Surgery longer than 2 hours E. Colloid administration F. Intraoperative hypotension G. Addison's disease H. Use of a Wilson frame
The correct answer is ABFH. Risk factors for the development of postoperative blindness include: intraoperative hypotension, male sex, obesity, anemia from blood loss greater than 1 liters, surgery greater than 5 hours in duration, use of a Wilson frame, and decreased percent colloid administration.
Which of the following parameters increase during pregnancy? (select four) A. Stroke volume B. Expiratory reserve volume C. Tidal volume D. Bleeding tendency E. Plasma volume F. PaO2 G. Residual volume H. Functional residual capacity
The correct answer is ACEF. In pregnancy, plasma volume, stroke volume, heart rate, tidal volume, respiratory rate, PaO2, and oxygen consumption all increase. FRC, ERV, and residual volume all decrease.
Which of the following can result in hypokalemia? (select four) A. thiazide diuretics B. triamterene C. mineralocorticoids D. spironolactone E. nonsteroidal anti-inflammatory drugs F. loop diuretics G. glucocorticoids H. heparin administration
The correct answer is ACFG. Drugs that can result in hypokalemia include: thiazides, loop diuretics, mineralocorticoids, glucocorticoids, and high-dose antibiotics such as penicillin and ampicillin. Aminoglycosides, which are associated with magnesium depletion are also associated with hypokalemia. Triamterene, spironolactone, and NSAIDs can result in hyperkalemia.
Which factors reduce MAC? (select four) A. Increased age B. Hypernatremia C. Lidocaine D. Polycythemia E. Hyperthermia F. Pregnancy G. A high FiO2 H. Alpha-2 agonist administration
The correct answer is ACFH. Factors that decrease MAC include increased age, hypothermia, alpha-2 agonists, acute ethanol ingestion, hypoxemia, hyponatremia, metabolic acidosis, lidocaine, anemia, hypotension, and pregnancy.
You are performing anesthesia for a patient undergoing a total hip replacement. The surgeon is using polymethylmethacrylate to cement the prosthetic in place. You know that polymethylmethacrylate will result in A. systemic hypertension B. intramedullary hypertension C. inhibition of platelet aggregation D. decreased pulmonary vascular resistance
The correct answer is B. As the polymethylmethacrylate hardens, it causes intramedullary (within the bone marrow) hypertension which results in the embolization of fat, marrow, cement, and air into the venous circulation. This can produce hypoxia, hypotension, dysrhythmias, and pulmonary hypertension. The circulating cement can also produce a decrease in systemic vascular resistance and a subsequent decrease in blood pressure.
Cardiotoxicity resulting in cardiomyopathy is most likely to occur in cancer patients treated with A. Cyclophosphamide B. Doxorubicin C. Methotrexate D. Vincristine
The correct answer is B. Cardiac toxicity resulting in cardiomyopathy occurs in up to 5 percent of cancer patients treated with doxorubicin. It may initially appear with symptoms similar to an upper respiratory infection and then rapidly progress to congestive heart failure.
Cholinesterase inhibitors produce A. relaxation of the detrusor muscle B. salivation C. bronchodilation D. tachycardia
The correct answer is B. Cholinesterase inhibitors produce increased salivary secretion, bronchoconstriction, and increased intestinal motility.
Closing the APL valve while a patient is breathing spontaneously can result in A. negative pressure pulmonary edema B. the inadvertent administration of CPAP C. collapse of the breathing bag D. hypotension
The correct answer is B. Closing the APL valve while a patient is breathing spontaneously will result in an increase in the breathing circuit pressure. The breathing bag can become distended and the patient can be exposed to CPAP.
The surgeon plans to use a tourniquet during a total knee arthroplasty. Which of the following statements regarding tourniquet use is correct? A. The blood pressure will commonly elevate slightly after tourniquet deflation B. Tourniquet inflation pressure should be 100 mmHg greater than the systolic blood pressure C. Tourniquet pain typically begins about 90 minutes into the procedure. D. Metabolic alkalosis typically occurs after tourniquet deflation
The correct answer is B. It is common for the blood pressure to decrease significantly after tourniquet deflation. The tourniquet should be inflated to about 100 mmHg above the systolic blood pressure. Tourniquet pain typically begins after 45-60 minutes. The release of the tourniquet is often associated with metabolic acidosis and increased arterial carbon dioxide levels.
The absorption of irrigating solution through open venous sinuses during transurethral resection of the prostate (TURP) occurs at a rate of A. 3-5 mL/min of resection time B. 10-30 mL/min of resection time C. 40-50 mL/min of resection time D. 75-100 mL/min of resection time
The correct answer is B. The amount of irrigating fluid absorbed through open venous sinuses during TURP depends upon the size of the prostate being resected, the pressure of the irrigating solution, the experience of the surgeon, and the duration of the resection. The amount of solution absorbed averages 10 to 30 mL per minute of resection.
Injection of 4-5mL of local anesthetic behind the lateral malleolus would result in numbness to the A. medial aspect of the foot B. posterior portion of the heel and sole of the foot C. lateral side of the hallux and the medial side of the second digit D. the distal portion of the sole of the foot
The correct answer is B. The sural nerve travels behind the lateral malleolus and provides sensory innervation to the posterior portion of the heel and sole of the foot. The saphenous nerve provides sensory innervation to the medial aspect of the foot. The deep peroneal nerve innervates the lateral side of the hallux and the medial side of the second digit. The posterior tibial nerve, which passes behind the medial malleolus, innervates the distal aspect of the sole of the foot.
Which of the following are characteristics of hypoplastic left heart syndrome? (select four) A. Mitral valve hyperplasia B. Aortic valve atresia C. Left ventricular hypoplasia D. Mixing of systemic venous and pulmonary venous blood E. Extracardiac congenital anomalies F. Hyperplasia of the ascending aorta G. A single ventricle H. Hypertrophic cardiomyopathy
The correct answer is BCDG. Hypoplastic left heart syndrome is characterized by left ventricular hypoplasia, mixing of systemic venous and pulmonary venous blood in a single ventricle which communicates directly with the pulmonary and systemic circulatory systems, hypoplasia of the ascending aorta, mitral valve hypoplasia, and aortic valve atresia. Extracardiac congenital anomalies are typically not present. Rapid decreases in pulmonary vascular resistance can result in a decrease in coronary and systemic blood flow, metabolic acidosis, high-output cardiac failure, and ventricular arrhythmias.
Which of the following are defining characteristics of tetralogy of Fallot? (select four) A. Atrial septal defect B. Ventricular septal defect C. Left ventricular hypertrophy D. Right ventricular hypertrophy E. Right ventricular outflow obstruction F. Left ventricular outflow obstruction G. An aorta that communicates with both ventricles H. Coarctation of the aorta
The correct answer is BDEG. The defining characteristics of tetralogy of Fallot are: a ventricular septal defect, right ventricular outflow obstruction, right ventricular hypertrophy, and an aorta that communicates with both ventricles. It is the most common cyanotic congenital defect of the heart. The right ventricle becomes hypertrophied because it is chronically exposed to the higher pressures of the left ventricle through the defect in the septum. If an atrial septal defect is present, the pathology may be referred to as a pentalogy of Fallot.
Which of the following statements regarding the use of a first generation laryngeal mask airway (LMA) is NOT true? A. It protects the airway from pharyngeal secretions B. The presence of a pharyngeal abscess is a contraindication to its use C. It results in a greater incidence of bronchospasm than an endotracheal tube D. It is contraindicated in patients with low pulmonary compliance
The correct answer is C. A first generation LMA doesn't protect against gastric secretions. Ventilation requiring pressures in excess of 20 cm H2O may result in inflation of the stomach. It can become malpositioned, resulting in an inability to ventilate. It is contraindicated in pharyngeal pathology such as tumor or abscess. Pathology at or below the level of the LMA may make it an ineffective means of ventilation.
In patients with chronic congestive heart failure, ventricular dilation occurs as a compensatory mechanism to allow for ejection of sufficient stroke volume. The relationship that predicts the increase in ventricular wall stress as this dilation occurs is attributed to: A. Poiseuille B. Dalton C. LaPlace D. Reynolds
The correct answer is C. LaPlace's relationship states that wall tension is proportional to the product of intraventricular pressure and ventricular wall radius. Poiseuille's law states that the flow of blood through a vessel is proportional to the fourth power of the radius of the vessel. Dalton's law states that the total pressure of a gaseous system is equal to the sum of the partial pressures of each individual gas. Reynolds number relates the tendency of a fluid to exhibit laminar or turbulent flow.
When doing an ankle block, the injection of local anesthetic between the tendon of the anterior tibial muscle and the tendon of the great toe will anesthetize which nerve? A. superficial peroneal nerve B. saphenous nerve C. deep peroneal nerve D. sural nerve
The correct answer is C. The injection of local anesthetic between the tendon of the anterior tibial muscle and the tendon of the great toe will anesthetize the deep peroneal nerve.
During nasotracheal intubation, the tracheal tube should be inserted into the nares A. upward at a 30 degree angle B. downward at a 30 degree angle C. perpendicular to the face D. with the beveled end of the endotracheal tube angled towards the turbinates
The correct answer is C. When performing a nasotracheal intubation, the tracheal tube should be inserted into the nares at an angle perpendicular to the face with the bevel directed away from the turbinates.
The light emitted from a laser differs from ordinary light in that it is (select three) A. diffuse B. refracted C. monochromatic D. always a short wavelength E. unidirectional F. coherent G. visible only in the infrared specturm H. a source of gamma radiation
The correct answer is CEF. The three ways that laser light differs from that emitted from an ordinary light are 1) it is monochromatic (a single wavelength), coherent (it oscillates in the same phase), and unidirectional. Lasers can be both long (CO2 laser) and short (YAG laser) wavelengths.
Which of the following are consistent with postcardiotomy syndrome? (select four) A. The symptoms are most similar to acute pericardial effusion B. The most common cause is bacterial endocarditis C. It is more common in pediatric patients D. It occurs more frequently after cardiac transplantation than cardiac bypass graft surgery E. The treatment is similar to that of pericarditis F. It can occur due to infective or autoimmune processes G. It can occur due to blunt or penetrating trauma H. Cardiac tamponade is the most common presenting symptom
The correct answer is CEFG. Postcardiotomy syndrome exhibits symptoms similar to acute pericarditis. Causes include infection, autoimmune processes, blunt or penetrating trauma, and occurs in 10-40% of patients who have had cardiac bypass graft surgery involving pericardiotomy. It occurs more frequently in pediatric patients. It is not very common in cardiac transplant surgery and this is believed to be due to immunosuppressant therapy. Cardiac tamponade is rare in this syndrome.
When the pressure gauge first drops below 745 psig on a nitrous oxide E-cylinder at room temperature, the amount of nitrous oxide left in the tank is about A. 100 L B. 200 L C. 300 L D. 400 L
The correct answer is D. Because E-cylinder nitrous oxide tanks contain nitrous oxide in both the liquid and gas state, the only accurate way to determine the amount of gas left in the tank is by weighing it. A full E-cylinder tank will hold 1590 liters of nitrous oxide. When the pressure gauge drops below 745 psig, the liquid form has been consumed. The amount of nitrous oxide in the gas phase at that point is about a quarter of the tank or around 400 liters.
What clotting factor may decrease during pregnancy? A. VII B. VIII C. IX D. XI
The correct answer is D. Factors XI and XIII are decreased in pregnancy. Factors II and V are unchanged. Virtually everything else is increased (factors I, VII, VIII, IX, X, and XII).
An example of an extrinsic trigger for asthma is bronchoconstriction due to A. placement of an endotracheal tube B. exposure to cold C. exercise D. inhalation of antigens that stimulate IgE release
The correct answer is D. Intrinsic asthma is caused by factors such as placement of an endotracheal tube, inhalation of irritants, exposure to cold, and exercise. Extrinsic asthma is due to triggers that activate the immune system such as inhaling allergens that stimulate the release of IgE antibodies.
Which of the following is associated with an increased risk of pneumonia in a patient undergoing long-term ventilation via an endotracheal tube? A. Frequent suctioning B. PEEP C. Pulmonary hypertension D. Low cuff pressure
The correct answer is D. Low cuff pressure in the endotracheal tube increases the risk that secretions can pass beside the cuff and into the lungs and is associated with an increased risk of pneumonia in patients on long-term ventilation.
Which of the following would be an appropriate component of your anesthetic management plan for a patient with acromegaly undergoing general anesthesia? A. Decreasing the tidal volume and respiratory rate B. Setting the I:E ratio to 1:4 C. Maintaining the FiO2 at less than 40% D. Increasing the tidal volume
The correct answer is D. Patients with acromegaly tend to have increased lung volumes and ventilation-to-perfusion mismatching. The increased lung volumes would warrant increased tidal volumes.
Which of the following electrocardiographic leads would be best for monitoring for the transmural injury that could occur during angioplasty procedures? A. Lead I B. Lead aVF C. Lead V1 D. Lead V3
The correct answer is D. ST elevation reflective of transmural injury as could occur during angioplasty procedures is best detected by monitoring leads III and V3.
Which of the following would be most likely to be decreased in an elderly patient? A. PR Interval B. QT Interval C. QRS width D. Heart rate variability
The correct answer is D. The number of pacemaker cells reduces by about 90 percent by age 70. This makes the patient more prone to prolongation of the PR interval, QRS duration, and QT interval. Heart rate variability also decreases.
Which of the following typically occurs in patients undergoing electroconvulsive therapy? (select four) A. Decreased cerebral blood flow B. Tachycardia and hypertension followed by bradycardia and hypotension C. Decreased cerebral oxygen consumption D. Memory impairment E. Increased intraocular pressure F. Transient apnea G. Postictal confusion H. Decreased intragastric pressure
The correct answer is DEFG. Electroconvulsive therapy is an electrically-induced grand mal seizure. The effects of the seizure include: up to a 7-fold increase in cerebral blood flow, increased cerebral oxygen consumption, a parasympathetic discharge (bradycardia and hypotension) followed by sympathetic nervous stimulation (tachycardia and hypertension), increased intraocular pressure and intragastric pressure during the seizure, postictal confusion, headache, nausea, transient apnea, and memory impairment.
Match the Anesthetic agent to its vapor pressure Nitrous Oxide 238 Isoflurane 669 Desflurane 157 Sevoflurane 39,000
The correct match is: Nitrous oxide to 39,000 Isoflurane to 238 Desflurane to 669 Sevoflurane to 157.
