TEST QUESTIONS
A 78-year-old otherwise-healthy woman arrives in the postanesthesia care unit after an urgent cystoscopy and ureteral stent placement for an impacted ureteral stone. In the operating room, there were no complications and only minimal blood loss. One hour later, she is febrile to 102.3°F, tachycardic with a heart rate of 117 bpm, and hypotensive with a noninvasive blood pressure of 73/42 mm Hg. Blood cultures are drawn and broad-spectrum antibiotics are initiated. A central venous catheter is placed, and the central venous pressure is measured at 2 mm Hg. The best next step in the management of her shock is Start dobutamine for increased inotropy Blood transfusion to a goal hemoglobin concentration of 12 g/dL Initiate nitroglycerin infusion to off-load the right ventricle Fluid resuscitation to restore adequate preload
Fluid resuscitation to restore adequate preload The patient has clinical evidence of shock for which the most common cause is sepsis (likely urosepsis in this case). Primary treatment of vasodilatory shock consists of repleting intravascular volume until adequate preload can be restored, followed by, vasopressor support to maintain adequate end-organ perfusion. The patient's history as otherwise healthy does not rule out cardiogenic shock but makes it less likely, particularly in the setting of fever. Institution of dobutamine for increased inotropy may be useful in cardiogenic shock but is unlikely to improve vasodilatory shock where cardiac output is typically already elevated. Nitroglycerin infusion can be useful in cases of cardiogenic shock secondary to right-ventricular failure, but in such a case, an elevated central venous pressure would be expected. Finally, while blood transfusion may be indicated to increase oxygen-carrying capacity and oxygen delivery in certain shock states, there is no evidence for a goal hemoglobin concentration of 12 g/dL. Fluid resuscitation should begin with crystalloid until more data can be gathered on the patient's condition.
Which of the following medications should be discontinued before the elective surgery? Ranitidine Monoamine oxidase inhibitors Metoprolol Atorvastatin
MAOI
A 32-year-old man is a helmeted victim in a car versus pole motor vehicle collision with prolonged extrication. He is found on secondary survey to have bilateral comminuted femur fractures and an open book pelvic fracture. He is brought emergently to the OR for external fixation. Before arrival to the OR, he has received 6 units of packed red blood cells and 4 units of FFP and remains hemodynamically unstable. His most recent laboratory test results include hemoglobin 6.9 mg/dL, platelets 150 000, INR 1.9, and fibrinogen 250 mg/dL. In addition to blood products, your colleague suggests administering tranexamic acid (TXA). Which of the following is your response? TXA given beyond 1 hour of injury may increase bleeding-related mortality. TXA given beyond 2 hours of injury may increase bleeding-related mortality. TXA given beyond 3 hours of injury may increase bleeding-related mortality. There is no difference in bleeding-related mortality in trauma patients given TXA
TXA given beyond 2 hours of injury may increase bleeding-related mortality. Hemorrhage is a leading cause of death among patients with major trauma. TXA is a synthetic derivative of the amino acid lysine and works by reversibly blocking lysine binding sites on plasminogen, thereby competitively inhibiting fibrinolysis. TXA has been shown to reduce bleeding in patients undergoing CPB, as well as other elective surgeries. The Clinical Randomization of Antifibrinolytic Therapy in Significant Haemorrhage (CRASH-2) trial demonstrated in a subgroup analysis that TXA given within 3 hours of injury (1 g in a 10-min bolus and then 1 g infused over the next 8 h) significantly reduced the risk of death due to bleeding. However, the same treatment given to trauma patients after 3 hours of injury significantly increased the risk of death due to bleeding. Though previous studies have demonstrated increased risk of VTE with the administration of TXA, in CRASH-2 there were no significant differences in the rate of vaso-occlusive events
In general, herbal medications should be stopped before surgery for at least _____ days: 3 14 10 7
14 days!!!!
A 65-year-old male with a history of mitral valve replacement 2 years back presents for a knee replacement. He is on warfarin since the time of valve replacement. As per ASRA guidelines, the ideal time to stop his warfarin prior to surgery would be 10 days 3 days 12 hours 5 days
5 days
dministration of large volumes of normal saline can lead to A metabolic alkalosis An anion gap lactic acidosis A hyperchloremic-induced nongap metabolic acidosis None of the above
A hyperchloremic-induced nongap metabolic acidosis 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.
Which of the following β-blockers is most suited for a patient with bronchospastic disease? Bisoprolol Acebutolol Metoprolol Propranolol
ACCE Cardioselectivity of agents like metoprolol is dose-dependent (β1-receptor-specific). Even the β1-receptor-specific agents can have some β2-blocking action at higher doses. β-Blockers with intrinsic sympathomimetic activity, like acebutolol, provide a unique advantage in patients with bronchospastic airway disease.
A 75-year-old patient with a history of hypertension is to undergo laparoscopic colectomy for carcinoma colon. Continuing of which of the following antihypertensive drugs, preoperatively, in the geriatric age group, can be associated with profound hypotension on induction of general anesthesia? Angiotensin-converting-enzyme (ACE) inhibitors Hydrochlorothiazide Metoprolol Furosemide
ACE inhibitors Multiple studies have shown propensity of ACE inhibitors to precipitate profound hypotension at induction of general anesthesia, especially in the geriatric age group. Hence, ACE inhibitors should be with held on the day of the surgery, especially in the elderly and for major surgeries.
Which of the following statements concerning non-opioid analgesics is FALSE? Acetaminophen is associated with impaired platelet function and gastrointestinal (GI) ulceration. Paracetamol has both analgesic and antipyretic properties but is devoid of anti-inflammatory effects. Dexmedetomidine is a highly selective α2-agonist that does not depress respiration. Gabapentin is effective for neuropathic pain syndrome and postoperative pain.
Acetaminophen is associated with impaired platelet function and gastrointestinal (GI) ulceration. cetaminophen is not associated with the impaired platelet function and GI ulceration that are seen with many nonsteroidal anti-inflammatory drugs. Paracetamol has both analgesic and antipyretic properties but is devoid of anti-inflammatory effects. Dexmedetomidine is a highly selective α2-agonist that does not depress respiration. Gabapentin is effective for neuropathic pain syndrome and postoperative pain
Fondaparinux exerts its effects by which of the following? Acting as an antagonist to free factor IX Acting as an antagonist to the expression of GP IIb/IIIa Acting as an antagonist to free factor VII Acting as an antagonist to free factor Xa
Acting as an antagonist to free factor Xa Fondaparinux can be used for both prophylaxis and treatment of deep venous thromboses (DVTs). It is a highly specific antagonist for free factor Xa and also binds ATIII. Fondaparinux is renally eliminated, and coagulation monitoring is not necessary because of its long half-life, unless it is used in patients with renal impairment, in which case it would require monitoring of factor Xa levels. At this time, there is no reversal agent for fondaparinux.
Abrupt withdrawal of steroids can lead to Malignant hypertension Psychosis Sickle cell crisis Addisonian crisis
Addisonian crisis or acute adrenal insufficiency during the perioperative period occurs in patients with known adrenal insufficiency or in those receiving chronic steroid therapy. The latter causes hypothalamic-pituitary axis suppression. Patients with adrenal insufficiency may present with refractory shock with electrolyte and glucose abnormalities. Treatment consists of administration of hydrocortisone and correction of associated derangements.
A 64-year-old woman with a 70-pack-year smoking history and hypertension was recently admitted to the hospital with a severe COPD exacerbation and is currently receiving 40 mg of prednisone daily. On hospital day 3 she begins to complain of abdominal pain and spikes a fever. Imaging demonstrates evidence of appendicitis, and she is scheduled for an urgent appendectomy. Throughout the procedure, you note that she is becoming gradually more hypotensive. You place a radial arterial catheter, and she is consistently in the 80s-90s/40s-50s. You decide to do which of the following? Administer 100 mg hydrocortisone IV (intravenously) in addition to placing an NGT and administering 40 mg prednisone. Place a central venous catheter, and start norepinephrine. Start peripheral phenylephrine, place an nasogastric tube (NGT), and administer 40 mg prednisone. Administer 100 mg hydrocortisone IV, and start peripheral phenylephrine.
Administer 100 mg hydrocortisone IV, and start peripheral phenylephrine. Patients may present to the OR who are on oral steroid regimens and require repeat dosing during surgery. This patient recently suffered an exacerbation of her COPD and has been placed on a course of oral steroids to abate the symptoms associated with her exacerbation. Given that she is becoming progressively hypotensive, one should administer "stress-dose steroids" at this time while concurrently initiating therapy with a vasoactive medication. It does appear that she would benefit from central line placement; however, that should not delay the initiation of appropriate treatment. It is unnecessary to give the patient her daily prednisone in addition to the hydrocortisone, and it is inappropriate to solely give her prednisone given her rapidly declining clinical picture. Reference: Kelly KN, Domajnko B. Perioperative stress-dose steroids
A 57-year-old otherwise-healthy male was leaving a dinner party when he was involved in a rollover car accident during which a foreign object became lodged into his right eye. He is taken to the OR for emergent surgical repair of a penetrating wound to his right globe. The patient's vital signs normalize and anesthesia is maintained with desflurane and nitrous oxide. Later in the case, conjunctival instillation of a phenylephrine (10%) solution results in immediate escalation of blood pressure from 105/70 to 220/115 mm Hg, while his pulse falls from 86 to 35 bpm. The ECG reveals new onset of ectopic ventricular complexes. The most appropriate treatment option at this time is Discontinue nitrous oxide Administer atropine Administer nitroprusside Ask the surgeon to stop
Administer nitroprusside Rationale:Hypertensive episodes during anesthesia should be tackled logically. Common causes are light anesthesia, hypoxia, and hypercarbia. In this case, excessive systemic uptake of the phenylephrine precipitated severe hypertension. Elevated diastolic pressures with ECG pathology necessitate immediate action to prevent further cardiovascular decline. Administration of sodium nitroprusside is beneficial to quickly reduce the blood pressure and decrease cardiac afterload.
Normal daily cortisol production (mg/day) in adults is 15 to 30 10 to 15 75 to 100 50 to 60
Adults normally secrete 15 to 30 mg of cortisol daily. This may increase to over 150 mg under conditions of stress.
Preoperative assessment of patients with diabetes mellitus should include 24-Hour creatinine clearance Cancellation of the surgical case if HbA1c >10% An assessment of functional status Pulmonary function testing
An assessment of functional status Complications of diabetes result largely from microangiopathy and macroangiopathy. Diabetes is a well-recognized risk factor for coronary artery disease (CAD). Cardiac autonomic neuropathy may mask angina pectoris and obscure the presence of CAD. Hence, a careful assessment of functional status and any symptoms such as increasing dyspnea on exertion and fatigue may be indicative of significant CAD. While diabetes is a leading cause of renal failure, there is no evidence that a preoperative evaluation with a 24-hour creatinine clearance is helpful. While the risk of complications of diabetes increases with increasing HbA1c levels, and there is evidence that higher HbA1c levels are associated with adverse outcomes following a variety of surgical procedures, there is insufficient evidence to recommend an upper limit of HbA1c prior to elective surgery. The risks associated with poor glycemic control should be balanced against the necessity for surgery.
A 75-year-old patient with a history of hypertension is to undergo laparoscopic colectomy for carcinoma colon. Continuing of which of the following antihypertensive drugs, preoperatively, in the geriatric age group, can be associated with profound hypotension on induction of general anesthesia? Angiotensin-converting-enzyme (ACE) inhibitors Furosemide Metoprolol Hydrochlorothiazide
Angiotensin-converting-enzyme (ACE) inhibitors Multiple studies have shown propensity of ACE inhibitors to precipitate profound hypotension at induction of general anesthesia, especially in the geriatric age group. Hence, ACE inhibitors should be with held on the day of the surgery, especially in the elderly and for major surgeries.
For patients on aspirin therapy at a high risk of cardiac events in the perioperative period, which of the following should be performed? Aspirin should be continued until surgery and discontinued for 6 weeks postoperatively. Aspirin should be discontinued 24 hours before surgery and resumed after 6 weeks. Aspirin should be discontinued at least 5 days (preferably 10 days) before surgery and resumed after 24 hours. Aspirin should be continued throughout the perioperative period.
Aspirin should be continued throughout the perioperative period. See answer explanation given for question 11. Aspirin is a noncompetitive inhibitor of cyclooxygenase (COX)-1 and COX-2. COX-1 helps to maintain the gastric lining and renal blood flow and initiates the formation of TxA2. COX-2 mediates the synthesis of prostaglandins responsible for pain and inflammation. Because of the noncompetitive nature of aspirin, platelets in circulation during treatment are irreversibly impaired, and its effects can only be reversed with platelet transfusion. Once aspirin therapy has been discontinued, the newly transfused platelets are not subject to its effects; however, the patient's native platelets remain affected and therefore are deemed "nonfunctional." Perioperative management of patients on antiplatelet therapy depends on both individual patient factors and the procedure being performed. In patients with coronary stents, elective surgery should be postponed for 4-6 weeks in those with bare metal stents and for 12 months in those with drug-eluting stents. In patients at high risk of cardiac events (exclusive of coronary stents), aspirin should be continued throughout the perioperative period. Finally, in patients at low risk of cardiac events, aspirin should be stopped 7-10 days before surgery and can be resumed 24 hours postoperatively.
Replacing 10 mg of morphine with 30 mg of ketorolac can increase the risk of Nausea Respiratory depression Bleeding Analgesia
BLEEDING Ketorolac is a nonsteroidal anti-inflammatory analgesic that is available in parenteral form. Administration of this medication will help avoid side effects that are associated with the use of morphine, such as nausea and respiratory depression. Ketorolac 30 mg produces equivalent analgesia compared with 10 mg of morphine. Since it is devoid of action on the sphincter of Oddi, it is a useful drug in patients who have pain secondary to biliary spasm. Like any other nonsteroidal anti-inflammatory drug, it does carry the side effect of inhibition of platelet function and increasing the chance of bleeding postoperatively.
Which of the following statements is true of glucose metabolism in the perioperative period? Catecholamines inhibit gluconeogenesis. Glucagon levels are decreased. ACTH levels are decreased. Blood glucose levels in nondiabetic patients may rise as much as 60 mg/dL.
Blood glucose levels in nondiabetic patients may rise as much as 60 mg/dL. Surgery provokes a physiologic stress response characterized by increased sympathetic tone and hyperglycemia and mediated through increased glucagon, ACTH, and GH. Catecholamines stimulate glycogenolysis and gluconeogenesis in the liver and inhibit glucose uptake in insulin-dependent tissues. α- and β-receptors have differing effects on pancreatic function; α-receptors inhibit the release of insulin, whereas β-receptors enhance insulin and glucagon release. During the intraoperative and immediate postoperative period, effects of α-receptors predominate. The net result of each of these processes is a dramatic increase in serum glucose, even in nondiabetic patients, as much as 60 mg/dL above preoperative levels
The effects of aspirin therapy rely primarily on the direct inhibition of which of the following? COX-1, TxA2 COX-2, TxA1 COX-1, COX-2 COX-1 only
COX-1, COX-2 See answer explanation given for question 11. Aspirin is a noncompetitive inhibitor of cyclooxygenase (COX)-1 and COX-2. COX-1 helps to maintain the gastric lining and renal blood flow and initiates the formation of TxA2. COX-2 mediates the synthesis of prostaglandins responsible for pain and inflammation. Because of the noncompetitive nature of aspirin, platelets in circulation during treatment are irreversibly impaired, and its effects can only be reversed with platelet transfusion. Once aspirin therapy has been discontinued, the newly transfused platelets are not subject to its effects; however, the patient's native platelets remain affected and therefore are deemed "nonfunctional." Perioperative management of patients on antiplatelet therapy depends on both individual patient factors and the procedure being performed. In patients with coronary stents, elective surgery should be postponed for 4-6 weeks in those with bare metal stents and for 12 months in those with drug-eluting stents. In patients at high risk of cardiac events (exclusive of coronary stents), aspirin should be continued throughout the perioperative period. Finally, in patients at low risk of cardiac events, aspirin should be stopped 7-10 days before surgery and can be resumed 24 hours postoperatively
Which of the following sets of values would you expect to observe in a patient with primary adrenal insufficiency? in terms of CRH (high or low) ACTH (high or low) Cortisol (high or low) Aldosterone (high or low)
CRH is high ACTH IS HIGH Cortisol is low Aldosterone is low
Which of the following best describes the mechanism of acetaminophen? Activation of GABA receptors Activation of lipoxygenase central a2 receptors Central inhibition of cyclooxygenase (COX) activation Inhibition of lipoxygenase activation
Central inhibition of cyclooxygenase (COX) activation Acetaminophen is both an analgesic and antipyretic. It is thought to act centrally by inhibiting activation of COX. It does not actually bind the COX enzyme but instead prevents the activation of COX by reducing heme at its peroxidase site. Acetaminophen also may modulate descending inhibitory serotonergic pathways. Acetaminophen is opioid-sparing and frequently comprises part of a multimodal analgesic regimen. Lipoxygenase is part of the pathway of arachidonic acid metabolism to leukotrienes. It is not involved in analgesia. Central a2 receptors are activated by clonidine and tizanidine. Both of these drugs have sedative, anxiolytic, and analgesic properties, but tizanidine has a shorter duration of action than clonidine and is also thought to have less effect on heart rate and blood pressure. This leads to decreased release of norepinephrine at both central and peripheral sites, which in part explains the roles these drugs play in a multimodal regimen. Both of these medications can cause hypotension. GABA receptors are activated by many anesthetic agents, such as benzodiazepines, but not acetaminophen.
A 68-year-old woman with a history of hypertension, hyperlipidemia, coronary artery disease, atrial fibrillation on dabigatran, and type 2 diabetes is brought to the OR for an emergent decompressive craniectomy after sustaining a spontaneous intraparenchymal hemorrhage with midline shift. Vitals are BP 150/75, HR 72, and RR 14. The neurosurgeon asks if there is "something you can give" to reverse the anticoagulant effects of her dabigatran. You reach for which of the following? Pertuzumab Kcentra Idarucizumab Bebulin Fresh frozen plasma
Correct optionIdarucizumab Dabigatran belongs to a class of medications called direct oral anticoagulants. It directly binds and inhibits thrombin, which ultimately leads to inhibition of secondary hemostasis. It is clinically indicated to prevent nonhemorrhagic strokes in nonvalvular atrial fibrillation. Patients taking dabigatran are at increased risk for life-threatening bleeding, and (A) idarucizumab is the first reversal agent approved to reverse its effects. It is only approved for reversal of dabigatran and is a monoclonal antibody that works by binding to the drug compound to neutralize its effect without procoagulant effects. (B and D) There are 2 forms of prothrombin complex concentrate: Bebulin (factors II, IX, and X), and Kcentra (factors II, VII, IX, and X). They are approved for the quick reversal of vitamin K-antagonist oral anticoagulants (eg, warfarin), particularly intracranial bleeding. (E) Recent guidelines recommend against administration of FFP in direct thrombin inhibitor-related intracranial hemorrhage. (C) Pertuzumab is a monoclonal antibody used for the treatment of metastatic HER2-positive breast cancer.
When comparing prothrombin complex concentrates (PCCs) with fresh frozen plasma (FFP), which of the following is true? PCCs require a type and cross before administration. PCCs require a larger volume for administration. PCCs have a higher risk of infection. PCCs have a faster correction of coagulopathy.
Correct optionPCCs have a faster correction of coagulopathy. PCCs are formulations of 3 (factors II, IX, and X) or 4 (factors II, VII, IX, and X) coagulation factors and an anticoagulant (heparin, antithrombin, or proteins C and S). PCCs are indicated for the reversal of vitamin K antagonists and critical bleeding associated with major surgery, trauma, or liver failure. PCCs have become the drug of choice for reversing the effects of oral anticoagulants over FFP because of their faster correction of coagulopathy, smaller volume of the product itself, decreased risk of infection, and transfusion reactions
Nitroprusside therapy for hypertension should be discontinued in the presence of Mitral regurgitation Acute myocardial infarction Increasing metabolic acidosis Renal failure
Correct optionRenal failure Rationale:Hallmark of nitroprusside poisoning is increasing metabolic acidosis secondary to impaired oxidative phosphorylation in the cell because of accumulation of cyanide ions. Acute myocardial infarction is not a contraindication in itself of nitroprusside therapy as long as it is needed to treat high blood pressure. Same is true for mitral regurgitation, and in fact, nitroprusside may be helpful as it may increase the cardiac output in this condition by decreasing the afterload. Renal failure may increase the availability of sulfate ion, which allows production of more thiosulfate to act as a donor and thus convert cyanide to thiocyanate. Prolonged administration of high doses of nitroprusside may lead to thiocyanate accumulation and toxicity.
A 54-year-old man is admitted to the intensive care unit for monitoring after a complicated left colectomy for diverticulitis. He has a history of type 2 diabetes mellitus on metformin. On arrival to the ICU, his blood glucose on an arterial blood gas is 254 mg/dL. One hour later, it is 435 mg/dL. The next appropriate step in his management is Recheck blood glucose in 1 hour Start IV insulin therapy with a goal glucose <120 mg/dL Restart home metformin Start IV insulin therapy with a goal glucose <180 mg/dL
Correct optionStart IV insulin therapy with a goal glucose <180 mg/dL The patient has a rapidly increasing blood glucose level that warrants control immediately. Restarting home metformin, while reasonable, is unlikely to have an acute effect on his hyperglycemia. IV insulin therapy is indicated in this patient. While earlier studies demonstrated a mortality benefit to intensive insulin therapy, subsequent data have shown an increased risk of hypoglycemia and failed to show a mortality benefit. It would be most reasonable to start IV insulin with a goal blood glucose of <180 mg/dL.
Cyclo-oxygenase (COX) exists as two separate isomers, COX-1 and COX-2. Which of the following statements regarding these isomers is/are TRUE? COX-2 mediates pain and fever. COX-1 is the constitutive enzyme form. COX-2 is the inducible form. COX-1 mediates hemostasis.
CorrectoptionCOX-2 mediates pain and fever. CorrectoptionCOX-1 is the constitutive enzyme form. CorrectoptionCOX-2 is the inducible form. CorrectoptionCOX-1 mediates hemostasis. The therapeutic benefit of nonsteroidal anti-inflammatory drugs is believed to be mediated through the inhibition of COX enzymes, types I and II, which convert arachidonic acid to prostaglandins. COX-1 is the constitutive enzyme that produces prostaglandins, which are important for general "housekeeping" functions such as gastric protection and hemostasis. COX-2, on the other hand, is the inducible form of the enzyme that produces prostaglandins that mediate pain, inflammation, fever, and carcinogenesis. (
Which of the following steroids lacks mineralocorticoid activity? Methylprednisolone Hydrocortisone Dexamethasone Prednisone
Dexamethasone t is important to understand steroids' relative glucocorticoid and mineralocorticoid potencies because in primary adrenal insufficiency, there is a deficiency of both glucocorticoids and mineralocorticoids. In secondary adrenal insufficiency, only glucocorticoid deficiency exists because of lack of ACTH stimulation. For instance, in patients receiving chronic steroid therapy, hypothalamic-pituitary-adrenal axis suppression may occur, leading to low CRH and ACTH levels and the resultant atrophy of the zona fasciculata and a decrease in endogenous cortisol production. Mineralocorticoids cause fluid retention, edema, and hypokalemia; thus, it is important to make a rational choice when selecting a steroid when stress dosing is indicated. Dexamethasone is unique in that it lacks mineralocorticoid activity. Hydrocortisone is the same molecule as endogenous cortisol and has both glucocorticoid and mineralocorticoid effects. Prednisone has approximately 5× the glucocorticoid activity as mineralocorticoid activity, whereas methylprednisolone has approximately 10× the glucocorticoid activity as mineralocorticoid activity.
Which of the following medications has been shown to be efficacious in the treatment of fibromyalgia? Hydrocodone Pregabalin Duloxetine Amitriptyline
Duloxetine Treatment of fibromyalgia requires a multidisciplinary approach that includes medication combined with nonpharmacologic therapies such as low-intensity, low-impact exercise; physical therapy; cognitive behavioral therapy; and patient education. Medications thought to be efficacious for the treatment of fibromyalgia include serotonin and norepinephrine uptake inhibitors, specifically duloxetine and milnacipran, pregabalin, amitriptyline, gabapentin, and γ-hydroxybutyrate. Hydrocodone and other opioids are not a treatment of choice for fibromyalgia. A 2015 systematic review noted that there is more evidence available on the harms of opioid therapy in chronic nonmalignant pain than on the benefits. They also reported that there was insufficient evidence to support long-term use of opioid therapy in patients with chronic nonmalignant pain. References: Gilron I, Chaparro LE, Tu D, et al. Combination of pregabalin with duloxetine for fibromyalgia: a randomized controlled trial.
A 65-year-old African American patient is undergoing laparoscopic repair of inguinal hernia under general anesthesia. He has a history of hypertension, diabetes, and depression. His medication list includes lisinopril, hydrochlorothiazide, metformin, and phenelzine. Intraoperative hypotension develops secondary to injury to inferior epigastric artery. Which of the following medications is relatively contraindicated to treat this hypotension? Ephedrine Norepinephrine Phenylephrine Epinephrine
Ephedrine Rationale:Phenelzine inhibits monoamine oxidase, an enzyme that metabolizes catecholamines, allowing their levels to build up in the adrenergic neurons. Ephedrine has both direct and indirect actions on adrenergic system. Indirect action involves release of exaggerated amounts of norepinephrine from the adrenergic neurons leading to catastrophic increase in blood pressure. More direct-acting medication like phenylephrine is a better choice in a patient using monoamine oxidase inhibitors.
Warfarin's primary mechanism of action is inhibition of the synthesis of vitamin K-dependent clotting factors. These factors include which of the following? Factors II, VII, VIII, and X and protein C Factors II, VII, VIII, and XII and proteins C and S Factors VII, IX, X, and XII and protein S Factors II, VII, IX, and X and proteins C and S
Factors II, VII, IX, and X and proteins C and S Warfarin is an anticoagulant agent that exerts its effect by competing with vitamin K for carboxylation-binding sites and inhibits the synthesis of vitamin K-dependent clotting factors, factors II, VII, IX, and X and proteins C and S. Given that proteins C and S both have a shorter half-life than the other factors, patients may become hypercoagulable during the initial phase of therapy, thus necessitating bridging with another anticoagulant. Warfarin therapy is monitored via INR for a target range usually between 2 and 3. Warfarin is metabolized by the liver and P450 CYP2 enzymes and can therefore interact with many other medications that are also metabolized by this system. In addition, the clinical effect will vary depending on the amount of vitamin K in a person's diet. Daily intake of vitamin K should remain as stable as possible during the patients' treatment course with warfarin to avoid fluctuations in their INR, necessitating adjustment of warfarin dosing. Reversal of warfarin depends on the clinical situation and the value of the measured INR. In stable patients with an INR above 5, warfarin should be held for 1 to 2 doses. Supplemental oral vitamin K should be administered if the INR is above 8. If a patient cannot take oral medication, vitamin K can be given intravenously or subcutaneously. In patients with major bleeding or those requiring emergency surgery, 4-factor (factors II, VII, IX, and X) PCCs and vitamin K or FFP if 4-factor PCCs are not available, should be given.
Which of the following statements regarding fibrinolysis is/are TRUE? Fibrin degradation products are produced by the action of t-PA on plasminogen. The primary fibrinolytic enzyme is t-PA. t-PA differs from streptokinase in that its action is more localized. Tissue plasminogen activator (t-PA) is produced by vascular endothelial cells.
Fibrin degradation products are produced by the action of t-PA on plasminogen. The primary fibrinolytic enzyme is t-PA. t-PA differs from streptokinase in that its action is more localized. Tissue plasminogen activator (t-PA) is produced by vascular endothelial cells. The process of fibrinolysis leads to dissolution of fibrin clots. Fibrinolysis serves to remodel fibrin clots and "recanalize" vessels that have been occluded by thrombosis. The primary fibrinolytic enzyme is plasmin, which is derived by the conversion of plasminogen to plasmin in the presence of t-PA and fibrin. Fibrin split products or fibrin degradation products are produced by the action of plasmin on fibrin clots. The therapeutic fibrinolytic agents streptokinase and urokinase differ from t-PA in that they activate circulating plasminogen, leading to more widespread fibrinolysis.
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 Dilutional thrombocytopenia Fibrinogen level of 250 mg/dL Temperature of 34.9°C Uremia
Fibrinogen level of 250 mg/dL Rationale: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.
A 69-year-old woman becomes hypertensive to 207/109 upon emerging from a general anesthetic for laparoscopic hysterectomy. She is subsequently hypoxic and her endotracheal tube has frothy clear secretions. Which of the following is the most likely diagnosis? Volume overload Flash pulmonary edema Negative pressure pulmonary edema Transfusion-associated circulatory overload
Flash pulmonary edema x201c;Flash pulmonary edema" is a general clinical term used to describe an acute and severe manifestation of acute decompensated heart failure, wherein there is a rapid accumulation of fluid within the lung's interstitial and alveolar spaces, as a result of acutely elevated cardiac filling pressures. The pathophysiology of flash pulmonary edema involves abnormal vasoconstriction and endothelial dysfunction because of sympathetic activation, renin-angiotensin-aldosterone activation, and impaired nitric oxide production. It is associated with renal artery stenosis. The mainstay of treatment is a loop diuretic, such as furosemide, as this group of diuretics also possesses potent antivasoconstrictor effects. Given the acute onset of pulmonary edema in the setting of severe hypertension, the most likely diagnosis here is flash pulmonary edema. Volume overload would more likely have developed gradually over the course of the anesthetic, assuming fluids were given throughout. As the patient was still intubated, negative pressure pulmonary edema, which develops due to negative pressure against a closed glottis, is unlikely. Finally, there is no mention of transfusion to suggest transfusion-associated circulatory overload.
Eptifibatide (integrellin) is an inhibitor of which of the following? Phosphodiesterase ADP receptors Cyclooxygenase GP IIb/IIIa receptors
GP IIb/IIIa receptors Eptifibatide belongs to the class of drugs known as GP IIb/IIIa receptor blockers, which inhibit the cross-linkage of fibrinogen. These medications are used for the management of acute coronary syndrome (ACS), and effects are monitored via serial activated clotting times (ACTs). Eptifibatide is renally excreted and thus has a prolonged mechanism of action in those with renal impairment. Currently, there are not any reversal agents available; thus reversal depends on clearance of the drugs, which have a half-life of approximately 2.5 hours. Reference: Carabini LM, Ramsey G. Hemostasis and transfusion medicine. In: Barash PG, Cullen BF, Stoelting RK, et al, eds. Clinical Anesthesia. 7th ed. Philadelphia: Wolters Kluwer Health; 2013:408-444.
Clinical manifestations of mineralocorticoid excess include Tetany Hypokalemia Metabolic acidosis Hypotension
HYPOKALEMIA Rationale:Hypersecretion of aldosterone results in increased sodium reabsorption in the distal renal tubule in exchange for potassium and hydrogen ions. This results in fluid retention, hypertension, metabolic alkalosis, hypokalemia, and muscle weakness.
Labetalol is relatively contraindicated for Treatment of hypertension in preeclampsia Hypertensive emergencies after cardiac surgery involving second-degree heat block Hypertension secondary to clonidine withdrawal Treatment of hypertension in aortic dissection
Hypertensive emergencies after cardiac surgery involving second-degree heat block Labetalol is a competitive antagonist at the α1 and β adrenergic receptors. It is a useful agent in the perioperative period because vasodilatation caused by α1 blockade is not accompanied with tachycardia with its attendant risks. It is a particularly useful drug in hypertensive patient with diagnosis of aortic dissection as it decreases the sheer force across the dissection. It does not cross the placenta and does not decrease the uterine blood flow even when patient is hypotensive, so it is used in obstetric patients with preeclampsia to control their blood pressure. Clonidine is a stimulant of α2 receptors, thus decreasing sympathetic activity, and its long-term administration leads to up regulation of adrenergic receptors. Sudden withdrawal of this medication leads to overactivity of the sympathetic system and a β-blocker antagonist is very helpful in controlling the manifestations of this overactivity. Abnormalities of cardiac conduction system are a relative contraindication to the administration of labetalol as it may worsen the degree of conduction blockade.
Clinical manifestations of mineralocorticoid excess include Hypotension Tetany Hypokalemia Metabolic acidosis
Hypokalemia Hypersecretion of aldosterone results in increased sodium reabsorption in the distal renal tubule in exchange for potassium and hydrogen ions. This results in fluid retention, hypertension, metabolic alkalosis, hypokalemia, and muscle weakness.
Physiologic effects of chronically elevated corticosteroid levels (Cushing syndrome) include all of the following, except Hypokalemia Hypotension Muscle wasting Glucose intolerance
Hypotension Rationale:Cushing syndrome is characterized by muscle weakness/wasting, glucose intolerance, hypertension, hypokalemia, weight gain, hypercoagulability, and osteoporosis.
Heparin-induced thrombocytopenia type 2 (HIT2) is mediated by which of the following? IgG antibodies binding to ATIII on the surface of platelets IgG antibodies binding to heparin-PF-4 complexes on the surface of red blood cells (RBCs) IgG antibodies binding to ATIII on the surface of RBCs IgG antibodies binding to heparin-PF-4 complexes on the surface of platelets
IgG antibodies binding to heparin-PF-4 complexes on the surface of platelets HIT is the development of thrombocytopenia within 5-10 days of initiating therapy with heparin. The disorder develops in 1%-5% of patients and leads to thromboembolic phenomena. UFH and LMWH can both cause HIT; however, HIT is more common with the use of UFH. Two forms of HIT exist; HIT1 is milder and involves only a mild thrombocytopenia, whereas HIT2 is a complex immune-mediated response causing hypercoagulability. In HIT2, IgG antibodies bind to heparin-PF-4 complexes on the surface of platelets, inhibiting hemostasis and thrombin generation. HIT should be considered in patients who have recently begun an anticoagulation regimen with heparin and show a fall in platelets to less than 150 000 or greater than 50% from baseline. Diagnosis is confirmed with either an ELISA or serotonin release assay. Treatment then consists of immediately stopping all forms of heparin and necessitates anticoagulation with another agent (except warfarin).
ll of the following are consequences of moderate hypothermia (33-35°C), except Prolongation of neuromuscular blockade Inhibition of platelet function Inhibition of drug metabolism Increases coagulation-factor activity
Increases coagulation-factor activity IT will exaccerabate post op bleeding it. reduces coagulation factor activity so makes you bleed more
Which of the following is the mechanism of action of ADP receptor antagonists such as clopidogrel? Promotion of the action of GP Ib Inhibition of the action of GP Ib Promotion of GP IIb/IIIa expression on the surface of activated platelets Inhibition of GP IIb/IIIa expression on the surface of activated platelets
Inhibition of GP IIb/IIIa expression on the surface of activated platelets Clopidogrel is a noncompetitive and irreversible P2Y12 ADP receptor antagonist, which prevents the expression of GP IIb/IIIa on the surface of activated platelets, inhibiting platelet adhesion and aggregation. ADP receptor antagonists are used clinically to inhibit thromboembolism, prevent myocardial infarction (MI), and prevent in-stent thrombosis. Clopidogrel is a "prodrug," meaning that it must be oxidized to its active form. Reference: Carabini LM, Ramsey G. Hemostasis and transfusion medicine. In: Barash PG, Cullen BF, Stoelting RK, et al, eds. Clinical Anesthesia. 7th ed. Philadelphia: Wolters Kluwer Health; 2013:408-444.
A 75-year-old patient with coronary artery disease, hypertension, and chronic obstructive pulmonary disease (COPD) is undergoing a left colectomy for cancer. He had a COPD exacerbation 4 months ago and was on steroids for a week at the time. Steroid replacement Should be given at a dose greater than 10 times the normal daily cortisol production rate Should include 100 mg of cortisol, tapered over 5 to 7 days Should not exceed 100 to 150 mg of cortisol equivalent per day Is not necessary in this patient
Is not necessary in this patient Patients who have received the equivalent of 5 mg of prednisone or more for a period of more than 2 weeks within the previous 3 months may not be able to respond appropriately to surgical stress due to adrenal suppression. These patients should receive perioperative steroid replacement therapy. The dose of steroids needed is controversial though. One recommended approach is to give a dose between 1 and 5 times the daily cortisol production (no more than 100 to 150 mg of cortisol equivalent) per day, beginning at the time of surgery and taper the replacement over 48 to 72 hours.
After neutralizing heparin, which of the following is the fate of the heparin-protamine reaction product? It is removed by the kidneys It is removed by the reticuloendothelial system It is excreted unchanged via gastrointestinal (GI) tract The only product remaining will be water since it is an acid-base reaction
It is removed by the reticuloendothelial system Protamine binds and effectively inactivates heparin because the positive charge of protamine neutralizes the negative charge of heparin. Timing of protamine administration should be determined by close communication with the surgeon. Too early administration may lead to clot formation in the cardiopulmonary bypass circuit. The electrically neutral heparinprotamine complexes are removed by the reticuloendothelial system. Protamine dosing is based on the amount of heparin initially required to produce the desired activated clotting time; protamine is then given in a ratio of 1 to 1.3 mg per 100 U of heparin. Another approach calculates the protamine dose based on the heparin dose-response curve and the estimation of heparin concentration using special monitors (Hepcon).
Factors that contraindicate ketorolac administration include all of the following except Active peptic ulcer disease Factor VIII deficiency Renal insufficiency Daily ingestion of aspirin
Ketorolac is a valuable nonsteroidal analgesic with modest anti-inflammatory action. It was the sole nonsteroidal anti-inflammatory drug available in intravenous form prior to the availability of IV ibuprofen. Thirty milligrams of ketorolac is equivalent in potency to 100 mg of meperidine or 10 mg of morphine. Unfortunately, it has many side effects that limit its use in the perioperative period. Inhibition of prostaglandin which is part of its analgesic mechanism of action leads to afferent arteriolar constriction.
Which of the following drugs is the most appropriate agent for acute treatment of hypertension in a preeclamptic patient? Labetalol Nitroglycerine Lisinopril Magnesium
Labetalol Treatment of hypertension in a preeclamptic patient aims at decreasing the risk of cerebral hemorrhage while maintaining and even improving tissue perfusion. Nitroprusside, a potent vasodilator of resistance and capacitance vessels with an immediate but evanescent action, is useful in preventing dangerous elevations in systemic and pulmonary artery blood pressure during laryngoscopy, and is ideal for treatment of hypertensive emergencies. Its infusion can be titrated to effect. Labetalol and hydralazine can be used to provide a longer lasting control of blood pressure but may not be fast enough in their action to control a sudden acute rise of blood pressure that is associated with this condition. Magnesium is primary therapy to prevent seizures in this condition. It is a smooth-muscle relaxant and helps with control of high blood pressure but in itself is not good enough to control the elevation of blood pressure in preeclampsia. Lisinopril is an angiotensin-converting enzyme inhibitor, which is contraindicated during pregnancy because of the risk of fetal abnormalities.
Which of the following medications should be discontinued before the elective surgery? Ranitidine Atorvastatin Monoamine oxidase inhibitors Metoprolol
MAO All of the medications mentioned in the question should be continued in the perioperative period, except monoamine oxidase inhibitors. By decreasing the metabolism of catecholamines, these medications cause an increase in the amount of norepinephrine available at the presynaptic adrenergic nerve ending. Use of indirect-acting sympathomimetic drug like ephedrine to treat hypotension will lead to exaggerated response with severe degree of hypertension and cardiac arrhythmias. Recommendation is to stop these agents at least 2 weeks before the planned surgery. Since this can cause problem in a patient who is dependent on this medication, this group of medication is falling out of favor. There is strong evidence to continue the use of β-blockers, cholesterol-lowering agents, and H2-blockers. Most hospitals have policies to ensure that patients using long-term β-blockers receive them in the perioperative period. Similarly, there is evidence that perioperative continued use of statins leads to better outcomes
You are taking care of a 45-year-old patient undergoing a left adrenalectomy for a pheochromocytoma. Intraoperative management includes Use of ketamine as an induction agent to counteract the effects preoperative of α-adrenergic blockade Magnesium sulfate infusion to treat hypertension Long-acting antihypertensive agents should be available to treat hypertension Judicious fluid replacement as these patients are usually volume-overloaded
Magnesium sulfate infusion to treat hypertension intraoperative management of pheochromocytoma resection includes avoidance of drugs (e.g., ketamine, ephedrine) or techniques that may stimulate the sympathetic nervous system. Intubation should be performed after a deep level of anesthesia is achieved and hypoventilation should be avoided. Despite adequate preoperative α- and β-blockade, hypertension may still occur. These should be treated with short-acting, easily titrated agents such as nitroprusside or nicardipine. Phentolamine may also be useful because it blocks α-adrenergic receptors. Magnesium infusions have been shown useful in managing hypertension by inhibiting catecholamine release and by altering adrenergic receptor response. Patients with pheochromocytomas are often hypovolemic and become hypotensive, and hypoglycemic (lack of catecholamine-induced glucose synthesis) after tumor ligation and resection.
Which of the following tests is used to confirm coagulation after stopping low-molecular-weight heparin (LMWH)? aPTT ACT PT None of the above
NONE use 10a At present, no conventional test (PT, PTT) can be used to quantify the clinical effects of LMWH on the coagulation system. Anti-Factor Xa estimation may be used in specific patients to monitor the coagulative effects of LMWH.
Nonsteroidal anti-inflammatory drugs (NSAIDs) are often used as part of "multimodal" analgesic therapy; some of the potential advantages include all of the following, except Can decrease postoperative pain intensity Indirect effect of decreasing opioid-related side effects Decreases opioid requirements Can improve wound healing
NSAIDs have not only many of the above-identified advantages, but also several potential side effects that the practitioner must remain cognizant of such as risk of gastrointestinal bleeding, renal injury, and the potential to impair wound healing.
Nitroprusside therapy for hypertension should be discontinued in the presence of Increasing metabolic acidosis Acute myocardial infarction Renal failure Mitral regurgitation
Nitroprusside therapy for hypertension should be discontinued in the presence of Increasing metabolic acidosis Acute myocardial infarction Renal failure Mitral regurgitation Hallmark of nitroprusside poisoning is increasing metabolic acidosis secondary to impaired oxidative phosphorylation in the cell because of accumulation of cyanide ions. Acute myocardial infarction is not a contraindication in itself of nitroprusside therapy as long as it is needed to treat high blood pressure. Same is true for mitral regurgitation, and in fact, nitroprusside may be helpful as it may increase the cardiac output in this condition by decreasing the afterload. Renal failure may increase the availability of sulfate ion, which allows production of more thiosulfate to act as a donor and thus convert cyanide to thiocyanate. Prolonged administration of high doses of nitroprusside may lead to thiocyanate accumulation and toxicity.
A 42-year-old patient is scheduled for a hernia repair under general anesthesia. His medications include fluoxetine, alprazolam, and lithium for bipolar disorder. In the preoperative area, he appears confused, has tremors, and is ataxic. Your next step would be to Cancel the case Proceed with the case Order a lithium blood level Consult a psychiatrist
Order a lithium blood level Because of its narrow therapeutic index, lithium dosing requires constant surveillance with monitoring of levels and dosage adjustment. Three types of lithium intoxication can occur—acute, acute or chronic, and chronic. Chronic lithium intoxication occurs in those patients on long-term lithium therapy.
Which of the following opioids would be most appropriate to treat pain in an elderly patient on fluoxetine? Tramadol Oxycodone Fentanyl Meperidine
Oxycodone It is not unusual for elderly patients to be on a myriad of medications. Thus, it is essential for the anesthesiologist to understand important interactions. Fluoxetine, a selective serotonin reuptake inhibitor, can, in combination with some drugs, lead to an increased risk of serotonin syndrome. Many anesthetic drugs, including opioids, increase serotonin levels. These include tramadol, meperidine, and fentanyl. Oxycodone has not been associated with an increased risk of serotonin syndrome. Serotonin syndrome can be fatal and is characterized by a triad of features: neuromuscular hyperactivity (such as tremor, clonus, and hyperreflexia), autonomic hyperactivity (such as fever, tachycardia, and diaphoresis), and change in mental status (agitation followed by confusion and eventually coma).It is not unusual for elderly patients to be on a myriad of medications. Thus, it is essential for the anesthesiologist to understand important interactions. Fluoxetine, a selective serotonin reuptake inhibitor, can, in combination with some drugs, lead to an increased risk of serotonin syndrome. Many anesthetic drugs, including opioids, increase serotonin levels. These include tramadol, meperidine, and fentanyl. Oxycodone has not been associated with an increased risk of serotonin syndrome. Serotonin syndrome can be fatal and is characterized by a triad of features: neuromuscular hyperactivity (such as tremor, clonus, and hyperreflexia), autonomic hyperactivity (such as fever, tachycardia, and diaphoresis), and change in mental status (agitation followed by confusion and eventually coma).
All of the following are true about diabetic patients, except Patients should take half or one-third of their insulin dose the morning of the surgery Patient with an insulin pump should continue the insulin at their basal rate Finger-stick blood glucose should be tested before taking the patient to the operating room Patients should continue their oral hypoglycemic agents the morning of the surgery
Patients should continue their oral hypoglycemic agents the morning of the surgery Patients taking oral hypoglycemic agents may experience delayed hypoglycemia in the absence of caloric intake in the intraoperative and postoperative periods. Hence, patients should be advised not to take oral hypoglycemic agents the morning of the surgery. In addition, metformin should be stopped at least 48 hours before surgery as it may precipitate the development of lactic acidosis during surgery. Patients on an insulin pump should continue the insulin at the basal rate.
Which of the following statements concerning regulation of serum potassium levels is/are TRUE? Potassium excretion is increased in the presence of nonreabsorbable anions in the renal luminal fluid. Epinephrine and exogenous β2-agonists cause an extracellular shift of potassium. Insulin causes an intracellular shift of potassium. Aldosterone increases potassium excretion.
Potassium excretion is increased in the presence of nonreabsorbable anions in the renal luminal fluid. Epinephrine and exogenous β2-agonists cause an extracellular shift of potassium. Insulin causes an intracellular shift of potassium. Aldosterone increases potassium excretion.
Nitroprusside therapy for hypertension should be discontinued in the presence of Renal failure Mitral regurgitation Acute myocardial infarction Increasing metabolic acidosis
Renal failure Hallmark of nitroprusside poisoning is increasing metabolic acidosis secondary to impaired oxidative phosphorylation in the cell because of accumulation of cyanide ions. Acute myocardial infarction is not a contraindication in itself of nitroprusside therapy as long as it is needed to treat high blood pressure. Same is true for mitral regurgitation, and in fact, nitroprusside may be helpful as it may increase the cardiac output in this condition by decreasing the afterload. Renal failure may increase the availability of sulfate ion, which allows production of more thiosulfate to act as a donor and thus convert cyanide to thiocyanate. Prolonged administration of high doses of nitroprusside may lead to thiocyanate accumulation and toxicity.
Tranexamic acid, a lysine analogue, acts by which of the following mechanisms? Reversibly binds to plasminogen, thereby preventing the degradation of fibrin Inhibition of COX-1 and COX-2 Inhibition of vitamin K-dependent clotting factors Inhibition of glycoprotein (GP) IIb/IIIa expression on the surface of activated platelets
Reversibly binds to plasminogen, thereby preventing the degradation of fibrin Tranexamic acid (TXA) is a synthetic derivative of lysine that competitively inhibits the binding site of plasminogen, preventing cleavage to plasmin that results in fibrinolysis. TXA decreases bleeding in cardiac surgery, liver transplant, and orthopedic procedures. It has recently been shown to decrease bleeding and all-cause mortality in trauma and has been shown to be effective in prevention and treatment for postpartum hemorrhage. TXA is renally excreted, and there have been few reported side effects. Reference: Carabini LM, Ramsey G. Hemostasis and transfusion medicine
Concurrent administration of all of the following anticoagulants and thrombolytic therapy should be avoided when planning for neuraxial blockade, except for Therapeutic dosing of low-molecular-weight heparin (LMWH) Thrombin inhibitors (desirudin, lepirudin, bivalirudin, and Argatroban) Subcutaneous heparin daily dose of 10,000 U or less Fibrinolytic and thrombolytic therapy
Subcutaneous heparin daily dose of 10,000 U or less According to the American Society of Regional Anesthesia and Pain Medicine anticoagulation guidelines, medications such as antiplatelet agents (Plavix, and intravenous glycoprotein IIb/IIIa inhibitors), thrombolytics, fondaparinux, direct thrombin inhibitors, or therapeutic LMWH present an unacceptable risk for spinal and/or epidural hematoma development without sufficient time lapse between administration of such medications and neuraxial techniques. Maximum administration of subcutaneous heparin of 5,000 U bid is estimated to be safe with epidural and spinal anesthesia. Heparin administration of 5,000 U tid is not known to be accepted in clinical practice in conjunction with neuraxial blockade.
The level of which coagulation factor may not be affected by advanced liver disease? V VII VIII II
VIII The liver produces all vitamin K-dependent factors, which are II, VII, IX, and X, and some vitamin K-independent factors, including factors V, XI, XII, and XIII. The liver also produces fibrinogen (factor I) and proteins C and S. Factor VIII is produced by both the liver and endothelial cells throughout the body. For this reason, factor VIII levels will likely be normal even in advanced liver disease.
Release of which of the following substances is most likely to lead to postoperative hyponatremia? Angiotensin II Renin Vasopressin Aldosterone
Vasopressin Nonosmotic release of vasopressin (ADH) during surgery can trigger hyponatremia, especially in conjunction with the administration of hypotonic fluids (eg, 5% or 10% dextrose). Activation of the renin angiotensin system would increase levels of angiotensin II, aldosterone, and renin but would result in decreased RBF and increased absorption of both sodium and free water. Vasopressin, on the other hand, increases free water reabsorption without affecting sodium absorption, resulting in an imbalance and subsequent hyponatremia. References: Butterworth JF, Mackey DC, Wasnick JD. Renal physiology & anesthesia. In: Morgan and Mikhail's Clinical Anesthesiology
Which of the following statements regarding acute adrenal insufficiency is/are TRUE? It usually requires continued steroid therapy for 4 to 6 weeks after the acute event. It rarely, if ever, occurs in the perioperative period. Treatment consists of fluid and electrolyte resuscitation, as well as steroid replacement. It may require the use of inotropes and invasive monitoring despite aggressive steroid treatment.
all of them Acute adrenal insufficiency is usually precipitated by sepsis, trauma, or surgical stress. Immediate therapy is mandatory regardless of the cause and consists of fluid and electrolyte resuscitation and steroid replacement. Steroid replacement is continued during the first 24 hours, and if the patient is stable, the steroid dose reduction begins on the second day. If the patient continues to be hemodynamically unstable after adequate fluid resuscitation, inotropic support and invasive monitoring may be necessary. (See page 1289: Treatment and Anesthetic Considerations.)
Physiologic effects of nitroglycerin include: decreased afterload cyanide production systemic venodilation coronary artery dilation
all of them Nitroglycerin is a systemic venodilator. In addition, at higher doses, nitroglycerin dilates systemic arterial beds. Therefore, it both reduces preload (by decreasing venous return) and reduces afterload (by decreasing systemic arterial pressure). Nitroglycerin is the drug of choice in the treatment of patients with coronary vasospasm because it is also an effective dilator of the coronary arterial bed, including stenosed arteries and collateral beds. However, nitroglycerin may also cause methemoglobinemia, especially in patients with deficiencies of methemoglobin reductase. Sodium nitroprusside, not nitroglycerin, may produce cyanide and thiocyanate upon metabolism, posing the risk of toxicity during prolonged infusions or after administration of relatively large quantities over short time periods
As per the American Society of Regional Anesthesia (ASRA) guidelines, which of the following drugs can be continued preoperatively in patients planned for neuraxial blockade for an elective procedure? Aspirin Warfarin Low-molecular-weight heparin Clopidogrel
aspirin As per ASRA guidelines, warfarin must be stopped at least 5 days prior and clopidogrel 7 to 10 days prior to elective surgery. Low-molecular-weight heparin in therapeutic doses must be stopped at least 24 hours prior, and when being used in prophylactic doses, it must be stopped at least 12 hours prior to an elective surgery requiring central neuraxial blockade. Aspirin use is no more considered as a contraindication to performing a neuraxial block.
Neuraxial block is not contraindicated for patients on which of the following drugs? Low-molecular-weight heparin Aspirin Clopidogrel Warfarin
aspririn As per ASRA guidelines (2010), aspirin intake by the patient is no more considered as a contraindication to performing a neuraxial block.
DDAVP (desmopressin) administration can increase the activity of all the following factors, except Factor VIII Factor VII von Willebrand factor
factor 7 it does not do Rationale: DDAVP, 0.3 μg/kg (intravenously over 20 minutes), can increase the activity of factors VIII and XII and the von Willebrand factor. DDAVP facilitates their release from the vascular endothelium. Hence, a second dose is usually not effective. DDAVP is very useful in reversing qualitative platelet defects, but is not recommended for routine use.
The Cushing's response to elevated intracranial pressure (ICP) includes: hypotension and bradycardia hypotension and tachycardia hypertension and tachycardia hypertension and bradycardia vasodilation and prolonged QRS
hypertension and bradycardia Patients may demonstrate the Cushing's response of hypertension and bradycardia, which signifies brainstem compression from increased ICP. (See page 1025: Emergent Surgery: Neurosurgical.)
Effects of furosemide administration in the perioperative period include Hypernatremia Hyperkalemia Decreased risk for acute tubular necrosis Metabolic alkalosis
metabolic alkalosis 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.
The effects of aspirin therapy can be reversed by infusing which of the following products? Platelets Protamine Vitamin K von Willebrand factor
plts Aspirin is a noncompetitive inhibitor of cyclooxygenase (COX)-1 and COX-2. COX-1 helps to maintain the gastric lining and renal blood flow and initiates the formation of TxA2. COX-2 mediates the synthesis of prostaglandins responsible for pain and inflammation. Because of the noncompetitive nature of aspirin, platelets in circulation during treatment are irreversibly impaired, and its effects can only be reversed with platelet transfusion. Once aspirin therapy has been discontinued, the newly transfused platelets are not subject to its effects; however, the patient's native platelets remain affected and therefore are deemed "nonfunctional." Perioperative management of patients on antiplatelet therapy depends on both individual patient factors and the procedure being performed. In patients with coronary stents, elective surgery should be postponed for 4-6 weeks in those with bare metal stents and for 12 months in those with drug-eluting stents. In patients at high risk of cardiac events (exclusive of coronary stents), aspirin should be continued throughout the perioperative period. Finally, in patients at low risk of cardiac events, aspirin should be stopped 7-10 days before surgery and can be resumed 24 hours postoperatively.
Which of the following is not a vitamin K-dependent factor? X II IX V VII
v Most of the coagulation proteins are synthesized by the liver. Four of the clotting factors (II, VII, IX, and X) require vitamin K for proper synthesis.
