2016 MCQs

ANSWER: A (Consensus A) References: Barash pg 1429, Miller Chapter 72 pg 2234 • Present with HYPERtension not hypotension due to acute volume overload • Other manifestations range from mild (restlessness, nausea, shortness of breath, dizziness) to severe (seizures, coma, hypertension, bradycardia, cardiovascular collapse) • Classic triad in awake patient o Increase in systolic and diastolic pressures associated with an increase in pulse pressure, bradycardia, mental status changes.

5. Which of the following is least likely to present in transurethral resection syndrome: a) hypotension b) bradycardia c) nausea d) confusion

ANSWER: B (Consensus B) (Barash Ch 27 Pg 767) Describes two studies on difficult mask ventilation. Identified clinical predictors: » Langeron study: - Presence of beard - BMI > 26 - Lack of teeth - Age > 55 - History of snoring » Kheterpal study: - High Mallampatic score - Poor mandibular protrusion - History of radiation therapy to neck - Male gender

100. Predictors of difficult bag mask ventilation, all except (answers remembered differently): a) inability to advance (?prognath) the mandible b) prominent teeth c) mallampatti 3 or 4 d) male e) Elderly

ANSWER: C (Consensus C) • Generally, opioids cause small, dose dependent increases in latency and decreases in amplitude of SSEPs. Their changes are not clinically significant. (Miller Chapter 46 pg 1517) Regarding A propofol infusion • As per table below increase latency and amplitude. Regarding Sodium nitroprusside for hypotension • ? Regarding D • Nitrous oxide causes differing effects on the SERs, depending on the sensory system monitored. It causes decreases in amplitude without significant changes in latency in SSEPs when it is used alone or when it is added to a narcotic based or volatile anesthetic drug (Miller chapter 46 pg 1516)

20. Which of the following is least likely to interfere with SSEP's for spine surgery? a) Propofol infusion b) Sodium nitroprusside for hypotension c) Remifentanyl infusion d) Nitrous oxide with fentanyl boluses

Answer D (Consensus D) • At dose of 0.2 to 0.3 mg/kg etomidate reduced CBF 34% and CMRO2 by 45% without altering MAP. • CPP is maintained is maintained or increased, and a beneficial net increase in the cerebral oxygen supply to demand ratio occurs.

21. Which correctly describes the effect of etomidate on brain physiology a) Decreased CMRO2, maintain MAP, Increased CBF b) Decreased CMRO2, decreases MAP, Increased CBF c) Increased CMRO2, decrease MAP, decreased CBF d) Decreased CMRO2, maintain MAP, decreased CBF

Answer D (Consensus D) • Anatomic dead space in the circle system begins at the Y piece

22. In a circle system at what point in the circuit does the dead space begin? a) Reservoir bag b) Inspiratory valve c) Fresh gas flow inlet d) Y piece

ANSWER: D (Consensus D) • According to P&P and Miller, morphine's effects are potentiated by MAOI's, but it does not affect serotonin reuptake and not associated with serotonin toxicity. o Morphine does not inhibit uptake of serotonin, but its opioid effects may be potentiated in the presence of MAO inhibitors (P&P pdf 1427) o "The phenylpiperidine series opioids, including meperidine, tramadol, and methadone appear to be weak serotonin reuptake inhibitors and have all been involved in serotonin toxicity reactions with MAOIs, whereas morphine, codeine, oxycodone and buprenorphine are known not to be serotonin reuptake inhibitors and do no participate serotonin toxicity with MAOIs (Miller Chapter 31 pg 909) Regarding A and C • Phenylpiperidine derivatives such as fentanyl and sufentanil act as weak serotonin reuptake inhibitors o "Derivatives of meperidine (fentanyl, sufentanil, alfentanil) have been associated with adverse reactions in patients treated with MAO inhibitors, although the incidence seems less than with meperidine" (P&P pdf 1427) o It is important to know that other common perioperative medications, such as methylene blue, which is a potent reversible MAOI, and the phenylpiperidine steroids of opioids (i.e. fentanyl and its congeners, methadone, meperidine, tramadol), which act as a weak serotonin reuptake inhibitors, have been reported to be associated with serotonin toxicity in small case reports. (Barash pg 174) Regarding B - False • "The interaction of meperidine with MAOIs is the most classic drug drug interaction associated with serotonin syndrome" (Barash pg 174)

1. For a patient who is taking a MAOI, which of the following will be the best option for analgesia? a) Fentanyl b) Meperidine c) Sufentanil d) Morphine

ANSWER: B (Consensus B) Repeat Pharm MCQ #42 (2011) » Lange Pg 186: A smaller induction dose is recommended in elderly patients because of their smaller Vd. » Miller Pg 824: The central compartment generally is smaller in older adults as a result of reduced cardiac output in these patients. Reduced cardiac output is associated with a higher peak plasma concentration, which is reflected by a smaller central compartment. » Stoelting P+P PDF Pg 301: Elderly patients require a lower induction dose (25-50% decrease) as a result of a smaller central distribution volume and decreased clearance rate and increased pharmacodynamic activity. » Barash Pg 486: Elderly patients and those in poor health require lower induction and maintenance doses of propofol as a result of their smaller central distribution volume and decreased clearance rate.

10. Elderly require lower induction and maintenance doses of propofol, this is due to which factor? a) Decrease amount of GABA receptors b) Decreased Central Vd c) Increased Clearance Rate d) Increased adipose tissue

ANSWER: A (Consensus A) Note: this question technically said "pneumothorax" rather than capnothorax. Reference: Barash. Ch 43. Anesthesia for Laparoscopic and Robotic Surgeries. 1268 Capnothorax has been reported during both intraperitoneal and extraperitoneal laparoscopic procedures. Although rare, it is a potentially life threatening complication. It is most common in procedures near the diaphragm (e.g., fundoplication and adrenorenal procedures). The suggested mechanisms include tracking of insufflated CO2 around the aortic, caval, and esophageal hiatuses of the diaphragm into the mediastinum with subsequent rupture into the pleural space. Treatment of capnothorax includes deflation of the abdomen and supportive treatment (Table 43-13). If there is minimal physiologic compromise, conservative treatment with close observation may be adequate because CO2 is rapidly absorbed. In addition to hyperventilation, use of PEEP may reduce the pressure gradient between the abdomen and the thorax during both inspiration and expiration and thus may inflate the lung and resolve capnothorax. In patients with severe compromise, placement of an intercostal cannula may be necessary, followed by a chest drain if reaccumulation occurs. After stabilization, the procedure can usually be resumed at lower IAP. Conversion to an open procedure might be necessary after stabilization. Barash. CHAPTER 52. Trauma and Burns. P 1509. Pleural Injury It has been suggested that a small closed pneumothorax can be safely managed by observation alone without a chest tube even in those patients who require positive-pressure ventilation as long as continuing vigilance is maintained. Based on the most recent Advanced Trauma Life Support recommendation and our own experience, we strongly believe that once diagnosed, a traumatic pneumothorax, no matter how small, should be treated with thoracostomy drainage before tracheal intubation and positive-pressure ventilation.

23. You are involved in a laparoscopic procedure on a healthy young female patient when you suspect the development of non-tension pneumothorax. Which of these is true: a) If the pt is otherwise stable can continue without a chest tube b) Application of peep is contraindicated c) Needle decompression is indicated d) Not remembered

ANSWER: B (Consensus B) • 2015 Recommendations (S503 Circulation part 10) —New and Updated BLS Modification: Relief of Aortocaval Compression Priorities for the pregnant woman in cardiac arrest are provision of high-quality CPR and relief of aortocaval compression (Class I, LOE C-LD). If the fundus height is at or above the level of the umbilicus, manual LUD can be beneficial in relieving aortocaval compression during chest compressions (Class IIa, LOE C-LD) Regarding D • 2015 Recommendations—New and Updated ALS Modification: Emergency Cesarean Delivery in Cardiac Arrest • During cardiac arrest, if the pregnant woman with a fundus height at or above the umbilicus has not achieved ROSC with usual resuscitation measures plus manual LUD, it is advisable to prepare to evacuate the uterus while resuscitation continues (Class I, LOE C-LD). In situations such as non survivable maternal trauma or prolonged pulselessness, in which maternal resuscitative efforts are obviously futile, there is no reason to delay performing PMCD (Class I, LOE C-LD). Perimortem caesarian delivery PMCD should be considered at 4 minutes after onset of maternal cardiac arrest or resuscitative efforts (for the unwitnessed arrest) if there is no ROSC (Class IIa, LOE C- EO). The clinical decision to perform a PMCD―and its timing with respect to maternal cardiac arrest―is complex because of the variability in level of practitioner and team training, patient factors (eg, etiology of arrest, gestational age), and system resources. Regarding A and C • No mention in Circulation Part 10: Special circumstances of resuscitation Note: MC causes of maternal cardiac arrest: Hemorrhage, cardiovascular diseases (including MI, aortic dissection, and myocarditis), amniotic fluid embolism, sepsis, aspiration pneumonitis, PE, eclampsia. Iatrogenic causes: Hypermagnesemia from magnesium sulfate administration and anesthetic complications

11. A patient who is in PEA arrest and 33 weeks pregnant, which is TRUE? a) consider avoiding defibrillation due to fetal dysrhythmias b) supine with manual left uterine displacement during CPR c) Cannot use epinephrine due to fetal tachyarrhymias d) Consider emergency C/S 5 mins after return of spontaneous circulation

Answer B onset 30 min peak 2-4 hours duration 6-8 hours

12. When is the peak effect of subcutaneous regular insulin a) 0.5-1 hours b) 2-4 hours c) 5-8 hours d) 9-12 hours

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13. Regarding oxygenation and high altitude: a) PaO2 can be increased by hyperventilation b) The effect of H2O vapour pressure becomes LESS significant c) Venturi Masks deliver LESS FiO2 than dialed d) The O2 concentration required to maintain PaO2 becomes LESS

ANSWER: A Reference: Miller Chapter 38 Preoperative Evaluation pg 1134, Lange Pg 684 (Miller) Bleomycin = pulmonary toxicity (Lange) Bleomycin = pulmonary fibrosis Regarding Doxorubicin (Adriamycin) • Cardiomyopathy MC Regarding C and D Vincristine or Cisplatin • Vincristine = peripheral neuropathy MC • Cisplatin = renal impairment Bonus Cyclophosphamide • Hemorrhagic cystitis MC

14. Regarding chemotherpeutic agents which is true. a) Bleomycin causes interstitial pulmonary fibrosis b) Doxorubicin - ? peripheral neuropathy c) Vincristine - ? cardiomyopathy d) Cisplatin - ? hepatic toxicity

Answer A

15. 1 month old term infant, which correctly represents normal vital signs? a) Hr 130 BP 75/45 b) Hr 170 BP 75/45 c) Hr 130 BP 90/55 d) Hr 90 BP 90/55

ANSWER: A (Consensus A) Repeat Other MCQ #58 (2012) • Patients allergic to bananas, avocados and kiwis have been reported to have antibodies that cross react with latex (Barash Chapter 12 pg 300) • Spina bifida, urogenital abnormalities, history of atopy are also risk factors

16. Which of the following is associated with cross reactivity with latex allergy? a) Bananna b) Walnut c) Shellfish d) Almond

ANSWER: B (Consensus B) Reference: Chestnut pg 743-4 • Obturator nerve palsy is susceptible to compressive injury as it crosses the brim of the pelvis or within the obturator canal. The mother may complain of pain when the damage occurs, followed by weakness of hip adduction and internal rotation with sensory balance over the upper inner thigh Regarding A Femoral • Damage may result from prolonged flexion, abduction and external rotation of the hips during the second stage of labour and also during procedures conducted in an excessive lithotomy position. • Patient may walk satisfactorily on a surface but may be unable to climb stairs • Patellar reflex is diminished or absent Regarding C Sciatic • Arises from compression of nerve usually in buttock • Loss of sensation below the knee with sparing of the medial side and loss of movement below the knee • Posterior cutaneous nerve and gluteal function are preserved, implying damage distal to the lumbosacral plexus, where the gluteal nerves branch off the sciatic nerve • It has occurred during childbirth under neuraxial blockade, either from sitting in one position too long or from a hip wedge misplaced during caesarean delivery. Regarding D Pudendal • Reference: Chestnut pg 526 • Pudendal nerve blocks are acceptable choices during the first and second stages of labour

17. Parturient has epidural placed at L34 and has a prolonged labor and instrumented delivery. Post partum she has numbness in medial distal aspect of her thigh and weakness of thigh thigh adductors. Which is the most likely nerve involved? a) Femoral b) Obturator c) Sciatic d) Pudendal

Answer D (Consensus D) Similar to 2015 MCQ #54 • Scoliosis has profound effects on the respiratory and cardiovascular systems. In patients with untreated scoliosis, respiratory failure and death usually occur by 45 years old • Vital capacity appears to be reliable prognostic indicator of perioperative respiratory reserve. Postoperative ventilation will most likely be required for patients with a vital capacity < 40% of predicted. • Although long term effect of scoliosis repair is to halt the decline in respiratory function, pulmonary function acutely deteriorates for 7-10 days after surgery. (Barash pg 1443) Regarding A • Scoliosis correction when Cobb angle > 50 (Barash), Cobb angle > 40 (Miller) and likelihood of curve progression is strong (Miller chapter 79 pg 2403) (Barash pg 1443) • Cobb angle > 65 degrees usually causes significant decreases in lung volume (Miller pg 2403) Regarding B • The primary abnormality in gas exchange is ventilation perfusion misdistribution, which contributes to hypoxemia. However, hypercapnia develops with increasing age as compensatory mechanisms fail. (Barash pg 1443) Regarding C • Cote: most idiopathic scoliosis is RIGHT-sided • Patients do exhibit RVH and hypertensive pulmonary vascular changes • Scoliosis associated with congenital heart conditions, including mitral valve prolapse, coarctation of aorta, and cyanotic heart disease suggesting a common embryonic insult or collagen defect (Barash pg 1443)

18. Adolescent for kyphoscoliosis surgery. Which of the following is true? a) Cobb angle 40 degrees is associated with significant restriction in lung volumes b) Hypercarbia is the presenting sign on ABG c) Right sided curves are associated with cardiac anomalies d) VC of <40% is predictive of need for post-op ventilation

ANSWER: C (Consensus C) Exact repeat of MCQ Other #85 (2008) References: Brash Pg 1541, Miller Ch 83 Pg 2494 • Nerve agents bind irreversibly to acetylcholineseterase (Option C) • Therefore do NOT have DIRECT muscarinic or nicotinic effects " effects are via #ACh at these receptors (Options B + D) • Muscarinic activity causes excessive PARASYMPATHETIC activity (Option A)

50. Sarin gas (organophosphate) attack. Which is true? a) Sympathomimetic? b) Direct muscarinic effects c) Irreversibly binds acetylcholinesterase d) Direct nicotinic effects

ANSWER: B (or C?) (Consensus 9B vs 5C) Similar to Q46 Thoracics MCQ #46 More likely B given the stem talks about jet ventilation, so will use the rates in the jet ventilation, apneic oxygenation section in Barash Barash section on rigid bronchoscopy /Apneic oxygenation (Pg 1057) • 40mm Hg(baseline) + 6 mm Hg (1st minute) + 15 mmHg (increase 3 mm Hg for 5 minutes) = 61mmHg • Apneic oxygenation. After preoxygenation and induction of general anesthesia, skeletal muscle paralysis and cessation of intermittent positive pressure ventilation, the PaCO2 increases. During the first minute the increase is approximately 6mmHg. Subsequently the rate of rise is approximately 3mm Hg/min Old Miller?/Tnotes • 40mmHg+ 6 mmHg (1st minute) + 15/20mmHg (increase 3 mm Hg for 5 minutes or 4mmHg) = 61- 66mmHg • Toronto Notes - Based off of old Miller can't find in most recent Miller!! Apparently from 6th edition of thoracic surgery from old question sets not in Miller 7th or 8th o With apnea, PaCO2 rises approximately 6 mmHg in the first minute because of the wash in of venous blood into the arterial compartment (venous blood has a carbon dioxide tension 6mmHg higher than that of arterial blood) and then 3 to 4 mmHg each minute thereafter because of normal carbon dioxide production. (Tnotes pdf 110) Barash section on breath holding (Pg 272) • 40 mmHg (baseline) + 12mmHg (1st minute) + 17.5 mmHg (increase 3.5mmHg for 5 minutes) = 69.5 mmHg • The rate of rise of PaCO2 in apneic anesthetized patients is 12 mm Hg during the first minute and 2.5 mm Hg during the first minute and 3.5 mm Hg/min thereafter significantly lower than in the awake state

19. Rigid bronchoscopy is performed. You are performing jet ventilation. If the starting PCO2 was 40mmHg and the patient has been apneic for 6 mins what is the PCO2? a) 50 mmHg b) 60 mmHg c) 70 mmHg d) 80 mmHg

answer B

51. Which is a component of Apgar? a) Eye opening b) Colour c) Respiratory rate d) Motor reflexes

ANSWER: A (Lange page 12) • Oxygen tank has approximately 625L • 625L / 5L/min = 125 mins = 2 hrs 5 mins

2. You are transporting a patient with an oxygen tank at 2000 psi running at 5L per minute. How long will the tank last? a) 2 hours b) 3 hours c) 4 hours d) 5 hours

ANSWER: B (Consensus B) Chestnut: Magnesium sulfate = best agent for prevention of recurrent seizures in women with eclampsia

63. An OB patient with pre-eclampsia has a seizure. What medication do you use to prevent another seizure? a) Etomidate b) Magnesium c) Propofol d) Diazepam

ANSWER: B (Consensus B) Regarding A: (Practical Cardiology Pg 190) Compared with unfractionated heparin, LMWH has lower plasma protein binding, greater bioavailability, more resistance to neutralization by platelet factor 4. Regarding C: LMWHs exhibit reduced inhibitory activity toward thrombin while retaining factor Xa inhibitory activity. Regarding D: Although monitoring of LMWHs is not performed routinely, the PT and aPTT most often are unaffected, necessitating measurement of anti-factor Xa activity. Furthermore, should rapid reversal of LMWH prove necessary, protamine is only partially effective.

24. What is true about LMWH compared to UFH. (doses and routes not given in question) a) Increased protein binding of LMWH compared to UFH b) Decreased clearance in renal failure of LMWH compared to UFH c) LMWH has no effect on Xa d) Protamine antagonizes LMWH

ANSWER: C (Consensus C) Reference: Miller Ch 67 Pg 2013 A, B & D will cause Pulmonary Vasodilatation. So, will improve pHTN & decrease RV afterload. Norepinephrine is least effective because the patient is normotensive and will cause pulmonary vasoconstriction. RV dysfunction or failure may also occur after CPB, usually because of inadequate myocardial protection, inadequate revascularization with resultant RV ischemia or infarction, preexisting pulmonary hypertension, intracoronary or pulmonary air embolism, chronic mitral valve disease, or tricuspid regurgitation (TR). Such RV failure may be evidenced by RV distention and hypokinesis on TEE, as well as by elevations in CVP and PA pressure (PAP). Therapy for RV failure includes increasing preload and inotropic support; milrinone, dobutamine, and isoproterenol are the usual first-line drugs. Other pharmacologic drugs occasionally used to induce pulmonary vasodilation include nitroglycerin and nitroprusside. One potential problem with the use of intravenous inodilator and vasodilator agents is that their effects are not limited to the pulmonary circulation. SVR must be adequate to maintain RV perfusion pressure. Inhaled drugs such as nitric oxide (see also Chapter 104), epoprostenol (Flolan), and inhaled iloprost are considered in refractory cases. Adjuncts to decrease PVR include hyperventilation (higher respiratory rate) to induce mild hypocapnia and preventing hypoxemia and acidosis. Rarely, patients may require support with an RVAD.

25. In a normotensive patient with acute RV failure secondary to pHTN, which one of these drugs is least effective? a) Nitric Oxide b) Dobutamine c) Norepinephrine d) Milrinone

ANSWER: C (Consensus C) Reference: Miller Ch 17 Pg 388 The arterial blood supply to the brain is composed of paired right and left internal carotid arteries, which give rise to the anterior circulation, and paired right and left vertebral arteries, which give rise to the posterior circulation. The connection of the two vertebral arteries forms the basilar artery. The internal carotid arteries and the basilar artery connect to form a vascular loop called the circle of Willis that permits collateral circulation between both the right and left and the anterior and posterior perfusing arteries. Three paired arteries that originate from the circle of Willis perfuse the brain: anterior, middle, and posterior cerebral arteries. The posterior communicating arteries and the anterior communicating artery complete the loop. The anterior and the posterior circulations contribute equally to the circle of Willis. Under normal circumstances, blood from the anterior and posterior circulations does not admix because the pressures in the two systems are equal. Similarly, side-to-side admixing of blood across the circle is limited. The vessels that originate from the circle provide blood flow to well delineated regions of the brain. However, in pathologic circumstances during which occlusion of one of the arterial branches occurs, the circle of Willis can act as an anteroposterior or side-to-side shunt to increase collateral blood flow to the region of the brain with reduced perfusion. A complete circle of Willis is shown in Figure 17-1, A. However, substantial variability exists in the anatomy of the circle of Willis, and a significant proportion of individuals may have an incomplete circular loop.1

26. Which arteries supply antegrade flow to the circle of willis? a) Internal carotid and middle meningeal artery b) Internal carotid and external carotid artery c) Internal carotid and basilar artery d) Vertebral artery and basilar artery

ANSWER: A (Consensus A) (Barash Ch 41 Pg 1180-6) At birth, the GFR is low, but increases significantly in the first few days, doubles in the first 2 weeks, but does not reach adult levels until about 2 years of age. The limited ability of the newborn's kidney to concentrate or dilute urine results from this low GFR and decreased tubular function. Regarding C: The pulmonary system develops rapidly during the last trimester, with important changes in both the number of alveoli and the maturity of the pulmonary vascular system.6 These systems have not matured enough to provide adequate gas exchange until about 24 to 26 weeks' gestation. The airways and alveoli continue to grow after birth, with alveoli increasing in number until about 8 years of age.

27. Concerning pediatrics, which is true? a) Kidney function is mature by 2 years of age b) Fasting for breast milk is 6h c) By the age of 3, the number of alveoli has reached peak levels d) The larynx is more caudad in the neck compared to adults

ANSWER: B (Consensus B) Reference: Barash 11, P283-284 A 24-hour smoking abstinence would allow carboxyhemoglobin levels to fall to normal but may increase the risk of PPC.

28. After patient stops smoking, how long before carboxyhemoglobin normalizes? a) 6h b) 24h c) 7 days d) 4 weeks

Answer: A

29. What are features in a patient with pre-eclampsia that make it severe? a) Headache b) SBP > 150 mmHg c) Left lower quadrant pain d) DBP > 100 mmHg

ANSWER: D (Consensus D) TLDR Sux: #IOP 6-12 mmHg (all others little effect or decrease IOP) Atropine + Rocuronium: little/no effect Propofol: deep inhaled/IV anesthetics $IOP 30-40% (Barash Ch 20 Pg 532) Intraocular pressure increases by 5 to 15 mm Hg after injection of succinylcholine, and this increase is still present after detachment of extraocular muscle, suggesting an intraocular etiology. Precurarization with a nondepolarizing blocker has little or no effect on this increase. This information has led to the widespread recommendation to avoid succinylcholine in open-eye injuries. However, it must be appreciated that inadequate anesthesia, elevated systemic blood pressure, and insufficient neuromuscular blockade during laryngoscopy and tracheal intubation might increase intraocular pressure more than succinylcholine. In addition, there is little evidence that the use of succinylcholine has led to blindness or extrusion of eye content.

34. Drug most like to increase intraocular pressure a) Atropine b) Propofol c) Rocuronium d) Succinylcholine

ANSWER: C (Consensus C) Power = ability of a study to detect a true difference; Power = 1 - β β error = probability of falsely accepting null hypothesis (false negative) " Type II error α error = probability of falsely rejecting null hypothesis (false positive) " Type I error

44. Calculate the power a) beta b) 1 + beta c) 1 - beta d) 1 - alpha

ANSWER: C (Consensus C) • Renal clearance = "almost entirely" • Half life 1-2 days. The half life is inversely proportional to glomerular filtration rate and this increases with age or renal disease (P&P pdf 815) • The most frequent cause of digitalis toxicity in the absence of renal dysfunction is the concurrent administration of diuretics that cause potassium depletion. TNotes pg 472 • Drugs completely dependent on renal excretion: o Digoxin, Ionotropes ABx (vanco, ceph, penicillin, aminoglycosides) • Drugs partially dependent on renal excretion: o Barbiturates, Pancuronium, Atropine and glycopyrrolate, Neostigmine, edrophonium, and pyridostigmine, Milrinone, Hydralazine, Sulphonamines, Chlopropramide, magnesium Regarding A Esmolol • Clearance is by plasma hydrolysis • Note: BB's that are renally cleared include Nadolol, Atenolol, Acebutalol, Sotolol, Bisoprolol o Neprhons Alter Absorption of Some Beta-blockers (Tnotes pdf 88) Regarding B Nifedipine • Nearly complete hepatic metabolism • Renal clearance ~ 80%, hepatic clearance < 15% (P&P pdf table 19-7 861, 866) Regarding D Propranolol • Hepatic clearance • Non selective BB

3. Which medication will accumulate the most in renal failure? a) Esmolol b) Nifedipine c) Digoxin d) Propranolol

ANSWER: C (Consensus C) Reference: Chestnut Ch 49 Pg 1131 Mannitol administered to a pregnant woman slowly accumulates in the fetus, leading to fetal hyperosmolality and the subsequent physiologic changes of reduced fetal lung fluid production, decreased fetal urine production, and increased fetal plasma sodium concentrations; however, mannitol in doses of 0.25 to 0.5 mg/kg has been reported in individual cases and appears to be associated with good maternal and fetal outcomes. Furosemide is an alternative diuretic that also should be administered cautiously

30. In a 32 week old gestational age with increased ICP secondary to an intracranial mass, what will happen when 1g/kg of mannitol is given? a) Fetal serum hypo-osmolality b) Fetal tachycardia c) Decreased fetal lung fluid production d) Increased fetal urinary output

ANSWER: D (Consensus D) Reference: Barash Ch 37 Pg 1052 The beneficial effect of selective PEEP 10 cm H2O (PEEP10) to the dependent lung is caused by an increased lung volume at end expiration (FRC), which improves the V/Q relationship in the dependent lung. The increase in FRC prevents airway and alveolar closure at end expiration. However, PEEP may lead to an increase in lung volume that could cause compression of the small inter-alveolar vessels and increase pulmonary vascular resistance. If this increase in resistance is limited to the dependent lung, blood flow can be diverted only to the nondependent (nonventilated) lung, increasing shunt fraction and further decreasing Pao2. The possibility that the application of PEEP can improve Pao2 in a diseased dependent lung (low lung volume and low V/Q ratio) with a low Pao2 (<80 mm Hg) during OLV has been addressed by Cohen et al.95 They found that the application of PEEP10 during OLV in patients with a low Pao2 may increase FRC to normal values, resulting in a lower pulmonary vascular resistance and in an improved V/Q ratio and Pao2. Presumably, patients with a higher Pao2 had a dependent lung with an adequate FRC, and the application of PEEP had the negative effect of redistributing blood flow away from the dependent ventilated lung (Fig. 37-19). In summary, in most circumstances PEEP alone would not improve arterial oxygenation, unless it could increase FRC to normal values. Since PV with low Vt is the recommended mode of ventilation during OLV, it most likely would lead to formation of atelectasis. Therefore, combining low Vt with a small amount of PEEP (5 cm H2O) to protect from development of atlectasis is the currently recommended ventilatory strategy. Continuous Positive Airway Pressure to the Nondependent Lung (A) The single most effective maneuver to increase Pao2 during OLV is the application of CPAP to the nondependent lung. A lower level of CPAP (5 to 10 cm H2O) maintains the patency of the nondependent lung alveoli, allowing some oxygen uptake to occur in the distended alveoli. CPAP should be applied after delivering an inspiratory Vt to the nondependent lung to keep it slightly expanded. CPAP, applied by insufflation of oxygen under positive pressure, keeps this lung "quiet" and prevents it from collapsing completely. Insufflation of oxygen without maintaining apositive pressure failed to improve Pao2. Intermittent reinflation of the collapsed (nondependent) lung with oxygen also resulted in a significant improvement in Pao2.

31. Thoracoscopy. Which will be the effect of PEEP 10 cmH20 on the ventilated lung in a lateral position during one-lung ventilation? a) Same as CPAP 10cmH20 on the isolated lung (non dependant) b) The pulmonary vascular resistance will be decrease c) The FRC will be decreased d) The effect on PaO2 will be variable

ANSWER: B (if EXCEPT then D) (Consensus B) Reference: Miller 7th Ed Ch 68 The pathophysiology of gas embolism is also determined by the size of the bubbles and the rate of intravenous entry of the gas. During laparoscopy, the rapid insufflation of gas under high pressure probably causes a "gas lock" in the vena cava and right atrium; obstruction to venous return with a fall in cardiac output or even circulatory collapse can result. Acute right ventricular hypertension may open the foramen ovale, allowing paradoxical gas embolization. Paradoxical embolism, however, may occur without patent foramen ovale. Volume preload diminishes the risk of gas embolism and of paradoxical embolism. Ventilation-perfusion (V/Q) mismatching develops with increases in physiologic dead space and hypoxemia. The diagnosis of gas embolism depends on the detection of gas emboli in the right side of the heart or on recognition of the physiologic changes from embolization. Early events, occurring with 0.5 mL/kg of air or less, include changes in Doppler sounds and increased mean pulmonary artery pressure. The low incidence of gas embolism during laparoscopy precludes the routine use of invasive or expensive monitors to detect embolization of small quantities of gas. When the size of the embolus increases (2 mL/kg of air), tachycardia, cardiac arrhythmias, hypotension, increased central venous pressure, alteration in heart tones (i.e., millwheel murmur), cyanosis, and electrocardiographic changes of right-sided heart strain can develop; all these changes are rarely consistently positive. Pulmonary edema can also be an early sign of gas embolism. Although pulse oximetry is helpful in recognizing hypoxemia, capnometry and capnography are more valuable in providing early diagnosis of gas embolism and determining the extent of the embolism. Petco2 decreases in the case of embolism owing to the fall in cardiac output and the enlargement of the physiologic dead space. Consequently, Δa-ETCO2 increases. The decrease in Petco2 may be preceded by an initial increase secondary to pulmonary excretion of the CO2, which has been absorbed into the blood. Aspiration of gas or foamy blood from a central venous line establishes the diagnosis. Routine preoperative insertion of a central venous line, however, does not appear justified for these procedures.

32. Laparoscopy. CO2 accidently insuflated in the IVC. Most likely: a) Increase in EtCO2 b) Increase in death-space c) Paradoxical embolism d) Metabolic acidosis (or alkalosis)?

ANSWER: D (Consensus D) Also only option that is a prothrombotic state rather than anticoagulated state Reference: Miller Ch 77 Pg 2349 Factor V Leiden is an abnormal variant of factor V that acts as a cofactor that allows activation of thrombin by factor Xa. The factor V Leiden variant cannot be easily degraded by activated protein C and thus leads to hypercoagulability. Patients with factor V Leiden abnormality do not intrinsically have an increased risk for epidural hematoma, but they may be maintained on anticoagulants for prophylaxis or treatment of DVT.

33. What will be the least problematic in regard of the probability of developing an epidural hematoma? a) The last dose of LMWH was 12 hours ago b) A patient with von Willebrand disease c) The IV Heparin was stoped 1 hour ago d) A patient with a Factor V Leiden variant

ANSWER: C (Consensus C, 5B) Repeat of Regional MCQ #4 (2010) The musculocutaneous nerve leaves fascial sheath of plexus appropriately at the level of the coracoid process. Therefore the axillary block will not always produce blockade of the musculocutaneous nerve unless the local anesthetic has spread proximally. The musculocutaneous nerve provides sensory innervation to the lateral forearm.

65. A patient is undergoing forearm surgery under axillary nerve block. What would indicate a failure of proximal spread within the axillary sheath? a) Preserved sensation in the 5th and medial 4th digits b) Preserved sensation of the medial forearm c) Preserved sensation of the lateral forearm d) Preserved sensation of the palmar surface of the hand excluding the medial 4th and 5th digits

ANSWER: D (Consensus D) (Miller Ch 89 Pg 2640) Minor adverse events are common after ambulatory surgery and anesthesia (86%). Drowsiness is the most common effect persisting after discharge (62%), and aches [A = FALSE] and sore throat are common in intubated patients (47% and 49%, respectively). Headache (25%) and dizziness (20%) also occur, but nausea and vomiting after discharge are less common (17% and 7%, respectively) [B = FALSE]. Patients may take 2 to 3 days before they are able to resume their usual activities. (Barash Ch 30 Pg 856) Nausea and vomiting are the most common reasons both children and adults have protracted stays in the PACU or unexpected hospital admission due to anesthesia. Nausea and vomiting are also the most common adverse effect in patients in the PACU. (Miller 7th Ed Ch 78 Pg 2448) Delayed discharge and unexpected hospital admission after outpatient surgery are the most commonly identified outcome measures after ambulatory anesthesia (Table 78-16). Not only does hospital admission add to the expense of the procedure, but it is also disruptive for the patient and the surgical facility. Ambulatory surgery facilities should have admission rates of less than 1%. Orthopedic (3.2%), general surgery (3.1%), otolaryngology (3.1%), and urology (2.9%) have the highest rates of unanticipated hospital admissions. However, freestanding and office-based units tend to have lower unanticipated hospital admission rates (<0.1%) because of differences in the types of patients and procedures, as well as the relative ease of admitting outpatients from hospital-based facilities. The most common reasons for unexpected admission are pain, bleeding, intractable vomiting, surgical misadventure (e.g., bowel or uterine perforation), more extensive surgery than expected, urinary retention, or lack of an escort.

35. Most common side effects persisting following discharge from ambulatory surgery: a) Pain b) Nausea and vomiting c) Urinary retention d) Drowsiness

Answer C

36. Which statistical data type is an ASA score a) Discrete b) Nominal c) Ordinal d) Continuous

ANSWER: C Reference: Miller 7th Ed Pg 2687 Major improvements in the treatment and management of HIV disease have decreased the incidence of new infections in children in North America and Western Europe. In young children, HIV infection is the result of vertical transmission from a seropositive mother. HIV-infected adolescents are affected in much the same way as adults; therefore, this discussion is limited to HIV in younger children. A mother who has an untreated HIV infection has a 12% to 30% chance of infecting her child. Perinatal treatment of infected mothers with antiretroviral drugs dramatically decreases these rates. Vertical transmission of HIV can occur in utero (30% to 40%), in the intra-partum setting by exposure to infected blood or cervico-vaginal secretions (60% to 70%), or in the postpartum setting by breastfeeding.

37. Most likely time for vertical HIV transmission a) 3rd trimister b) 1st trimester c) Labour and delivery d) Breastfeeding

ANSWER: C (Consensus C) Regarding B, C, D: (Miller Ch 29 Pg 785) The extent of rebreathing and the conservation of the other exhaled gases depend on the fresh gas flow rate. Higher fresh gas flow rates result in less rebreathing and greater waste gas. Contemporary circle systems are usually operated in a semiclosed manner, meaning that some waste flow is always vented through the APL valve or the waste gas valve associated with the ventilator. The use of low gas flows (≈1.0 L/minute) or minimal flows (≈0.5 L/minute) during anesthesia is an example. A semiopen system, as it pertains to the circle system, connotes higher fresh gas flows where minimal rebreathing would occur and more waste gas is vented. The potential advantages of conducting minimal fresh gas flow anesthesia include a decreased use of volatile anesthetic agents, improved temperature and humidity control, and reduced environmental pollution. The disadvantages include difficulty in rapidly adjusting anesthetic depth and the theoretical possibility of accumulation of endogenously released gases (e.g., carbon monoxide [CO], acetone, methane) or volatile anesthetic-absorbent related degradation products (e.g., compound A, CO). A closed circuit is one in which the rate of oxygen inflow exactly matches metabolic demand, rebreathing is complete, and no waste gas is vented (APL valve remains closed). A volatile anesthetic agent is added to the breathing circuit in liquid form in precise amounts or is initially introduced through the vaporizer. Closed-circuit anesthesia maximizes the advantages of low and minimal flow anesthesia. However, the technical demands of the technique relative to the benefits make it impractical for routine use with contemporary equipment, thus it is rarely employed. Regarding A: (Miller Ch 29 Pg 781) The circle system consists of several (7) essential components, including (1) a fresh gas inflow source, (2) inspiratory and expiratory unidirectional valves, (3) inspiratory and expiratory corrugated tubes, (4) a Y-piece that connects to the patient, (5) an overflow or adjustable pressure limiting (pop-off) valve (the APL valve), (6) a reservoir or breathing bag, and (7) a canister containing a carbon dioxide absorbent

38. What is true regarding classic circle system: a) Has 4 components b) Closed system has no rebreathing c) Semi-closed system can use low gas flows d) Open system has partial rebreathing

answer D Summary Effects » decreased FHR variability: Atropine, decreased CNS activity,Anticonvulsants, EtOH, Insulin if hypoglycaemia, MgSO4, Steroids, Promethazine, Other Beta blockers (not propranolol, metoprolol) » Minimal effect on FHR variability: Propranolol, Metoprolol, Glycopyrrolate Variability is greatly influenced by the parasympathetic tone, by means of the vagus nerve; maternal administration of atropine, which readily crosses the placenta, can eliminate some variability. In humans, the sympathetic nervous system appears to have a lesser role in influencing variability. Maternal administration of the beta-adrenergic receptor antagonist propranolol has little effect on FHR variability.

39. In a parturient, what drug will cause decreased fetal heart rate variability a) Glycopyrrolate b) Metoprolol c) Propranolol d) Atropine

ANSWER: A (Consensus A) Although amiodarone produces less hypotension, compared with bretylium, hypotension and bradycardia are its main side effects. Amiodarone's pharmacologic effects persist for longer than 45 days. (Miller ch. 47 p. 1444) (P+P PDF Pg 925) IV administration of amiodarone may result in: » Hypotension - most likely reflecting peripheral vasodilating effects of drug » AV heart block

76. What is a side effect of giving IV amiodarone too quickly? a) Hypotension b) Bronchospasm c) Tachycardia d) Pain on injection

ANSWER: A (Consensus A) • Posterior ischemic optic neuropathy is by far the most common cause of postoperative visual loss from spine surgery. Summary risk factors ION from Barash (Barash pg 1024) • Suggested risk factors for ION o Hypovolemia, hypotension, anemia, venous congestion, edema, adverse drug effects, and individual patient variation in anatomy and physiology of the optic nerve flow. • Risk factors of ION (based on Case study) o Obesity o Male gender o Wilson frame o Long duration of surgery o Greater estimated blood loss o Decreased percent colloid replacement of blood o No association with level of blood pressure or hematocrit Regarding B hemoglobin 90 • Controversial • ASA transfusion practice guidelines in surgical patients suggests transfusion generally not required HgB > 8.0 g/dL (Miller Ch 100 pg 3022)

4. For major spine surgery, which increases the chances of perioperative visual loss: a) prolonged duration of surgery b) hemoglobin of 90 c) female d) slightly head up positioning (neck neutral)

ANSWER: B (Consensus B) Reference: P+P Ch 30 Pg 575 The elimination half time of gabapentin is brief, suggesting that multiple daily doses are necessary. Gabapentin is well absorbed after oral administration (newest P+P version says poorly absorbed though), is not metabolized or bound to plasma proteins, but is excreted unchanged by the kidneys. The dose should be decreased in patients with renal dysfunction. Side effects of gabapentin are limited but may include somnolence, fatigue, ataxia, vertigo, and GI disturbances. Pharmacokinetic drug interactions with other drugs do not seem to occur reflecting the absence of protein binding and any effect on metabolism of other drugs. Regarding D: Inhibits Ca channels

40. Regarding Gabapentinoids, which is true: a) Pregabalin is superior analgesic relative to Gabapentin for the management of neuropathic pain b) Gabapentin needs to be renally dose adjusted in patients with kidney dysfunction c) Gabapentinoids are not indicated for post-herpetic neuralgia d) Gabapentin selectively binds to presynaptic voltage gated sodium channels

ANSWER: A (Consensus A) C is equivalent dose but would go with A given immediate release morphine would be q4h rather than q8h Reference: Barash Ch 56 Pg 1621 40 mcg/kg/h in 40 kg person IV dose per hour = 1600 mcg/h = 1.6 mg/h Oral dose per hour = 1.6 mg/h x 3 = 4.8 mg/h Per 4 h = 4.8 mg/h x 4 = 19 mg q4h Per 8 h = 4.8 mg/h x 8 = 38 mg q8h

41. 40kg patient receiving 40 mcg /kg/hr or morphine. Switch to oral medication. What is the most appropriate conversion? a) 20 mg po q4h b) 20 mg po q6h c) 40 mg po q8h d) 60 mg po q6h

ANSWER: A (Consensus A) CPB core temp: PA/oxygenator = bladder (high u/o) > NP = tympanic = esoph > rectal/skin = bladder (low u/o) (Barash Ch 38 Pg 1094) Central temperature can be measured with urinary bladder catheter or with a thermistor from a PAC. Depending upon the case, nasopharyngeal or tympanic temperature probes may be used (as in cases of deep hypothermic circulatory arrest). Rectal and skin probes record peripheral temperatures, which lag behind central measurements during both cooling and rewarming periods. (Miller Ch 54 Pg 1643) Even during cardiopulmonary bypass, the core temperature monitoring sites (e.g., tympanic membrane, nasopharynx, pulmonary artery, and esophagus) remain useful. In contrast, rectal temperatures lag behind those measured in core sites. Consequently, rectal temperature is considered an "intermediate" temperature in deliberately cooled patients. During cardiac surgery, bladder temperature is equal to rectal temperature (and therefore intermediate) when urine flow is low, but it is equal to pulmonary artery temperature (and thus core) when flow is high. Because bladder temperature is strongly influenced by urine flow, it may be difficult to interpret in these patients. The adequacy of rewarming is best evaluated by considering both "core" and "intermediate" temperatures.

42. Which is the least reliable measure of core body temperature in a patient undergoing CPB? a) rectal b) nasopharyngeal c) distal esophagus d) tympanic membrane

ANSWER: C (Consensus C) (Kaplan Ch 16 Pg 474) Manipulation or torsion of the aorta or vena cava may result in regional or global cerebral ischemia. During CPB, the aortic cannula can misdirect either cardiac or pump flow away from one or more head vessels while leaving the radial artery pressure unaltered. Alternatively, a malpositioned venous cannula may impair return from the head without noticeable change in central venous pressure or return flow to the venous reservoir. Resulting intracranial hypertension leads to ischemic depression of the EEG. (Barash Ch 38 Pg 1090) In the event of poor venous drainage, adjustment of the venous cannulae, raising the height of the operating table, or application of suction usually corrects the problem.

43. Patient on CPB has temp 32 degrees, EEG is flat, and has bulging sclera. What is the most appropriate: a) mannitol 50 g IV b) increase CPB flow c) check position of venous cannula d) check position of aortic cannula

ANSWER: C (Consensus mainly C - 3B) Repeat of Pharm #169 (2013) where we had same conclusion of C (including Captain F document) Sources: Lange Pg 186, Miller Pg 824, Stoelting P+P PDF Pg 299, Barash Pg 486-7 (Barash) EHT = 1-3 h (Stoelting P+P) EHT = 0.5 - 1.5 h Regarding A (false): (Miller) Some studies suggest that propofol may exhibit nonlinear pharmacokinetics. The pharmacokinetics of propofol has been described by two-compartment and three-compartment models. Recall: (Stoelting) Zero-order processes happen at a constant rate. This is represented as a straight line with a slope of k (the rate constant). Also, given that propofol has all these half-lives, this would suggest not a zero-order kinetic behaviour. Regarding B (false - not sure what exactly this option means): (Miller) The volume of distribution of the central compartment has been calculated at between 6 and 40 L, and the volume of distribution at steady state has been calculated as 150-700 L. Based on this, and the Miller table, it would be safe to say propofol's Vd is on the higher side of things. Regarding D (false): Propofol has a rapid onset of action. Awakening from a single bolus dose is also rapid due to a very short initial distribution half-life (2-8 min). The clearance of propofol exceeds hepatic blood flow, implying the existence of extrahepatic metabolism. This exceptionally high clearance rate probably contributes to relatively rapid recovery after continuous infusions.

45. Which is a pharmacokinetic or pharmacodynamic property of a propofol induction? a) zero order kinetics b) small volume of distribution in well perfused organs c) elimination half-life is a few hours d) action is halted by hepatic metabolism

ANSWER: C (Consensus C) Given the vague stem and answer options, it appears the question wants to ask about treatment of myxedema coma. Option A would be nonspecific treatment potentially for hyperkalemia, DKA, etc, which is unlikely what the question is asking for given the highlights of neck mass and hypothermia. Note that hydrocortisone is good for thyroid storm too!

46. 55 year old woman in ICU intubated, neck mass, stupor, hypothermic and hypotensive. What should you administer to this patient? a) glucose & insulin b) PTU & labetalol c) Levothyroxine & hydrocortisone d) IV fluids only

ANSWER: B (Consensus B) Phentolamine of course seems the most obvious answer. I just wanted to do some research specifically around the wording of "reversing" cocaine-induced vasospasm. The AHA documents are pretty clear that Phentolamine does reverse coronary vasospasm and beta blockers can worsen it. Not much discussion around benzodiazepines in this mechanism although it is one of the first line agents for cocaine-induced chest pain and MI. (ACLS 2010, not updated in 2015, "Special Circumstances") Catheterization laboratory studies demonstrate that cocaine administration leads to reduced coronary artery diameter. This effect is reversed by morphine, nitroglycerin, phentolamine, and verapamil; is not changed by labetalol; and is exacerbated by propranolol. Several studies suggest that administration of β-blockers may worsen cardiac perfusion and/or produce paradoxical hypertension when cocaine is present. (AHA 2008 Circulation - Management of Cocaine-Associated Chest Pain and Myocardial Infarction) • Cardiac catheterization studies demonstrate that nitroglycerin reverses cocaine-associated vasoconstriction • Verapamil reverses cocaine-associated coronary vasoconstriction but CCB have NOT demonstrated improved survival • Phentolamine returned coronary arterial diameter to baseline, suggesting that phentolamine may be useful for the treatment of cocaine-associated ischemia

47. Reverses cocaine induced vasospasm: a) midazolam b) phentolamine c) esmolol d) metoprolol

ANSWER: C (Consensus C) Repeat of Regional MCQ #29 (2011) TLDR Summary Increased baricity = predictable change in dermatomes = more hypotension + decreased duration of block (Barash Pg 916) The height of spinal block is thought to be determined by the cephalad spread of local anesthetic within the CSF. The baricity of the local anesthetic solution relative to patient position is probably the most important. Baricity is defined as the ratio of density (mass/volume) of the local anesthetic solution to the density of CSF. Baricity is important in determining local anesthetic spread and thus block height because gravity causes hyperbaric solutions to flow downward in CSF to the most dependent regions of the spinal column, whereas hypobaric solutions tend to rise in CSF. Thus the anesthesiologist can exert considerable influence on block height by choice of anesthetic solution and proper patient positioning. Regarding A (false): if drug dose is held constant, higher blocks tend to regress faster than lower blocks. Consequently isobaric anesthetic solutions will generally produce longer blocks than hyperbaric solutions using the same dose. Greater cephalad spread results in relatively lower drug concentration in the CSF and spinal nerve roots. As a result, it takes less time for local anesthetic concentration to decrease below the minimally effective concentration. Regarding B (false): higher block = more hypotension. Regarding D (false): most patients can sense the onset of spinal block within a very few minutes after drug injection regardless of the local anesthetic used. However, there is a significant difference among drugs in the time to reach peak block height. No mention regarding baricity specifically.

48. Increasing the baricity of spinal anesthetic does which? a) increases duration of block b) decreases hypotension c) predictable change in dermatomes d) decreased time of onset

ANSWER: C (Consensus C) References: Barash Pg 963, Miller Pg 1726, Lange Pg 986, Cousins PDF Pg 588 I wonder if the original question said "suprascapular" or "supraclavicular" nerve? Either way, Option C would be the most correct answer. Recall that the supraclavicular nerve is a branch of the cervical plexus. Note that Cousins seems to be the only textbook that refers to the suprascapular nerve as a branch of the cervical plexus (PDF Pg 2258). I think this is a typo (also remember the "Cs" go together - supraClavicular with Cervical plexus). The suprascapular nerve branches early off the brachial plexus. (Cousins) The supraclavicular nerve (C3-4) innervates the "cape of the shoulder." Although it is frequently blocked from cephalad local anesthetic spread during the interscalene approach, adequate anesthesia is often absent after the supraclavicular brachial plexus approach. The suprascapular nerve (C5-6) branches from the upper trunk. Depending on how proximally this branching occurs in relationship to where the block needle is placed, the suprascapular nerve may require a separate anesthetizing procedure for surgery involving the shoulder joint. Lange (quoted below) also comments that the supraclavicular block does not reliably anesthetize the suprascapular nerve (as compared to the interscalene approach) therefore inferring that usually it is blocked with the interscalene block. (Miller) Radiographic studies suggest a volume-to-anesthesia relationship, with 40 mL of solution associated with complete cervical and brachial plexus block. Regarding A (false): (Barash) a lateral approach (using nerve stimulator technique) may improve plexus cord localization and reduce risk of puncture to both the pleura and axillary artery. Regarding B (false): (Barash) Infraclavicular block blocks musculocutaneous nerve + axillary nerve more consistently than axillary block because they branch off high in axilla. Regarding D (false): (Lange) the supraclavicular block does not reliably anesthetize the axillary and suprascapular nerves, and thus is not ideal for shoulder surgery. Sparing of distal branches, particularly the ulnar nerve, may occur.

49. Which of the following statements about blocks of the brachial plexus is true? a) The lateral approach to the infraclavicular block should be avoided in patients with significant impairment of pulmonary function b) The axillary block is associated with more reliable block of musculocutaneous compared to infraclavicular c) The suprascapular nerve is usually blocked by cephalad spread of local anesthetic with the interscalene block d) The supraclavicular block often spares the median nerve

ANSWER: B (Consensus B) Reference: Miller Ch 20 Pg 489-90 Bainbridge Reflex: § Stretch receptors in RA wall + cavoatrial junction • Increase in right-sided filling pressures sends vagal afferent signals to cardiovascular center in medulla • The afferent signals inhibit parasympathetic activity • Causes INCREASE in HR § Also direct effect on SA node by stretching the atrium causing increase in HR § Changes in HR are dependent on underlying HR before stimulation Baroreceptor Reflex (Carotid Sinus Reflex) - responsible for maintenance of blood pressure § Capable of regulating arterial pressure around preset value through negative feedback loop § Circumferential and longitudinal stretch receptors located in carotid sinus and aortic arch • Sends afferents to nucleus solitarius (in cardiovascular center of medulla) via glossopharyngeal and vagus nerves • Activation of stretch receptors causes response from depressor system ∼ Decreased sympathetic activity " decreased contractility, HR, vascular tone ∼ Activation of parasympathetic system " decreased HR, contractility Chemoreceptor Reflex § Chemosensitive cells in carotid bodies and aortic body • Respond to changes in pH status + blood O2 tension • At arterial PO2 of < 50 mmHg or acidosis " impulses sent along sinus nerve of Hering (branch of glossopharyngeal nerve) + Vagus nerve to chemosensitive area of medulla ∼ Responds by stimulating respiratory centers " #s ventilatory drive ∼ Activation of parasympathetic system " decreases HR + contractility Bezold-Jarisch Reflex § Chemoreceptors + Mechanoreceptors within LV wall • Sense noxious ventricular stimuli • Induces triad of hypotension, bradycardia, coronary artery dilatation • Activated receptors communicate along unmyelinated vagal afferent type C fibers ∼ Reflexively increase parasympathetic tone • Thought to be cardioprotective reflex because it invokes bradycardia § May be modulated by Natriuretic peptide receptors stimulated by endogenous ANP or BNP

52. Which reflex is elicted by stretch receptors located in the wall of the right atrium and the cavoatrial junction? a) Chemoreceptor reflex b) Bainbridge reflex c) Baroreceptor reflex d) Bezold-Jarisch reflex

ANSWER: C (Consensus C) (Miller Ch 10 Pg 246) - Controlling the time and place of death so that timing of organ donation can be optimized has obvious medical and ethical advantages (Option A) § The decision to donate organs is made before death, allowing time for discussion and informed consent (Option D) § The dual decision to withdraw life-sustaining interventions + donate vital organs after death can create ethical conflicts - risk that patient's interests will be minimized or ignored in favour of organ recipient - The point at which actual death has occurred in DCD donors is unclear (Option C) § Loss of consciousness occurs quickly after asystole, but brain function can continue for some time, and irreversible brain injury may nor occur for many minutes § Many protocols call for organ retrieval to begin only 2 minutes after circulation has stopped - Option B is a good thing of course - the patient's interests should always be protected (Barash Pg 1461) Donation After Cardiac Death Background (however does not delve much into ethics) - Criteria for DCD donors are distinct from brain-dead donors § DCD donors typically have severe whole-brain dysfunction but electrical activity in the brain § Death is defined by cessation of circulation (arterial monitoring showing pulse pressure is zero, or Doppler monitoring showing no flow) and respiration - The decision to withdraw care must be made prior to and independent of any discussion about organ donation - Suitable DCD donors are those in whom death is anticipated within 1-2 hours of withdrawal of life support - Informed consent is required for organ donation and for any preorgan recovery procedures, such as drug administration or vascular cannulation - Plan for donor's care should be in place if patient does not die within the anticipated time frame, and ideally care should be transferred back to the team that knows the patient and family - Circulation and respiration must be absent for a minimum of 2 minutes before the start of organ recovery - Barash refers to an ASA reference document on DCD but I cannot find it in the ASA website or by google - The Canadian DCD recommendations (2006) also do not discuss the ethics as framed in this question

53. Organ donation after cardiac death (DCD) could be considered ethically questionable because of which of the following? a) The timing of death and donation are controlled b) The interests of the patient are protected until after death c) Uncertainly regarding when brain function ceases following asystole d) The decision to donate is made before death

ANSWER: C (Consensus C) Severe AR = main contraindication to IABP All other options are actually indications for IABP placement

54. Which of the following is a contraindication to insertion of an intra-aortic balloon pump? a) Cardiogenic shock b) Severe mitral regurgitation c) Severe aortic regurgitation d) Unstable angina

ANSWER: A (Consensus A, 2C) Maybe C? EXCEPT B? Caudal block for bilateral inguinal hernia repair - pretty much always helpful, rare complications + opioid-sparing (Cote Pg 455) Regional anesthesia has been safe and effective in children with CHD. Advantages of regional anesthesia, such as epidural and spinal techniques, include an effect largely limited to the surgical site, decreased number of systemic medications, a potentially brief recovery period, and usually a more pleasant experience for the child. Regional anesthesia retains the potential for hemodynamic compromise, particularly in hypovolemic children or those with a fixed cardiac output. It is also contraindicated in those with coagulation defects. Regarding Cardiac Shunts: (Cote Pg 329) In children with dependent shunts, the direction and degree of intracardiac shunting are determined by the circulatory dynamics. Control of circulatory dynamics to minimize the shunt is a major goal of anesthesia management. Because shunting depends on the relationship between SVR and PVR, anesthesia management often revolves around control of relative vascular resistances. In children with dependent right-to-left shunts, the shunt increases when SVR decreases or PVR increases. In children with dependent left-to-right shunts, the shunt increases when SVR increases and PVR decreases. Regarding C: Regarding Volume Overload Lesions: (Cote Pg 293) Volume overload lesions typically are caused by left-to-right shunting at the atrial, ventricular, or great artery levels. If the location of the left-to-right shunt is proximal to the mitral valve (eg ASDs, partial anomalous pulmonary venous return, unobstructed total anomalous pulmonary venous return), right heart dilation will occur. Lesions distal to the mitral valve (eg VSD, PDA, truncus areriosus) lead to left heart dilation. Diuretic therapy and afterload reduction are beneficial in controlling pulmonary over-circulation and ensuring adequate systemic cardiac output. Regarding B: only true if cyanotic or prosthetic material.

55. 2 year old 12 kg patient with sub aortic VSD for bilateral inguinal hernia repair, which would be helpful? a) Caudal block for post op pain b) Endocarditis prophylaxis c) Diuretics & Fluid restriction d) 4th option

Answer A Pharmacodynamic drug interactions cause the C50 of one drug to shift in response to the administration of a second drug. This drug interaction can be additive, supra-additive (synergistic) or infra-additive (antagonistic). In general, additive drug interactions occur when combining drugs acting by the same mechanism and synergistic or antagonistic interactions when combining drugs acting by a different mechanism. (Pg 934) Regarding propofol and sevoflurane: for both EEG suppression and tolerance to stimulation, the interaction of propofol and sevoflurane were additive. Chapter

56. The interaction between inhaled and IV anesthetics is most commonly described as: a) Additive b) Infra-additive c) Synergystic d) 4th option

ANSWER: B (Consensus B) The best answer is usually Phenylephrine, but seeing that is not an option, the best available is Esmolol as a beta blocker to decrease infundibular spasm. It is also the only option that does not go against your hemodynamic goals. References: Cote Pg 342-3 Anesthetic Goals are essentially those of any right-to-left shunt + infundibular spasm prevention § Maintain intravascular volume + SVR (ie AVOID decreases in SVR) § AVOID increases in PVR (ie acidosis, #airway pressures, tachycardia, acidosis, hypoxia, hypercapnia) § AVOID increases in contractility (# infundibular spasm) Management of TET spell § 100% O2 § Early and aggressive use of a vasoconstrictor • Phenylephrine, Norepinephrine § Hyperventilation § IV fluid bolus § Sedation/analgesia § Sodium bicarbonate § β-blockers to relax infundibuluar spasm and $ HR (usually Propranolol is given as example) Regarding other question options: § Dopamine increases HR + contractility § Ephedrine increases HR + contractility § Milrinone increases contractility + decreases SVR

64. You are taking care of a patient with TOF. All of a sudden the patient becomes hypotensive and the saturation drops to 80%. What is the best medication to treat? a) Dopamine b) Esmolol c) Ephedrine d) Milrinone

ANSWER: A (Consensus A) Option A is the best answer if they are referring to the loading dose as the problem. Option B may be correct because Dexmedetomidine can be used as the sole agent in a general anesthetic (which would mean 100% decrease in MAC requirement?) Regarding A (true): (Miller Pg 858) The incidence of hypotension and bradycardia may be related to the administration of a large IV "loading" dose. Omitting the loading dose or not giving more than 0.4 μg/kd reduces the incidence of hypotension or makes it less pronounced. Regarding B (possibly true): Miller, Barash, and Lange all just say Dexmedetomidine significantly decreases MAC requirements but do not quantify by how much. Stoelting P+P says Dexmedetomidine decreases MAC for volatile anesthetics in animals by greater than 90% compared with a plateau effect between 25% to 40% for clonidine. In patients, isoflurane MAC was decreased 35% and 48% by Dexmedetomidine plasma concentrations of 0.3 ng/mL and 0.6 ng/mL, respectively. (Miller Pg 858) Dexmedetomidine can also produce profound sedation, and it has been used as a total IV anesthetic when given at 10 times the normal sedation concentration range. Regarding C (false): (Stoeling P+P) Despite marked dose-dependent analgesia and sedation, there is mild depression of ventilation. Dexmedetomidine in high doses (loading dose 1 μg/kg IV then 5-10 μg/kg/h) produces total IV anesthesia without associated depression of ventilation. Regarding D (false): (Miller Pg 858) The most commonly reported hemodynamic adverse reactions associated with Dexmedetomidine in a phase III trial in 401 patients were hypotension (30%), hypertension (12%), and bradycardia (9%). I would not qualify 9% as "very rare".

57. Regarding dexmedetomidine, which is TRUE? a) Hypotension risk increases with infusion following loading dose. b) It reduces the minimum alveolar concentration by 80%. c) High doses cause respiratory depression. d) Bradycardia is very rare.

ANSWER: A (Consensus A) References: Barash Pg 1364, Cote Pg 673 Characteristic signs and symptoms of acute epiglottitis include sudden onset of fever, dysphagia, drooling, thick muffled voice, and preference for the sitting position with the head extended and leaning forward. Retractions, labored breathing, and cyanosis may be observed in cases in which respiratory obstruction is present. However, in the early stages, the patient may be pale and toxic without respiratory distress.

58. Which is LEAST consistent with epiglottitis? a) Toxic appearance lying quietly on stretcher. b) Patient drooling. c) Patient fevered. d) Muffled voice.

Answer D Substantial reduction, and essentially paralytic ileus for 24h Regarding A Hyperthyroidism does decrease gastric emptying Regarding B (true but not as bad as Option D): (P+P PDF Pg 1174) The basic defect of diabetic Gastroparesis appears to be one of impaired neural control. Delayed gastric emptying of solids is the most consistent abnormality in diabetics with Gastroparesis and is the most predictably responsive to pharmacologic manipulation. Diabetics patients may also have GI neuropathies (eg esophageal enteropathy, Gastroparesis, constipation, diarrhea, fecal incontinence). They may have delayed gastric emptying, and therefore they may be at increased risk of pulmonary aspiration of gastric contents. Regarding C (false): (Barash Ch 42 Pg 1231) Certain medical conditions may affect gastric emptying. Although diabetes mellitus delays gastric emptying, this may require years to fully develop. Recent evidence suggest that Gastroparesis may be multifactorial. Indeed, hyperglycemia alone can delay gastric emptying in both diabetics and nondiabetics.

59. Which decreases gastric emptying MOST? a) Hyperthyroidism. b) Diabetes mellitus. c) Hypoglycemia. d) Laparotomy within 24 hours.

ANSWER: B (Consensus B) E3, V3, M4 = 10

6. Patient was in a major motor vehicle crash. Patient has sustained injuries to the abdomen and head. On your preoperative assessment: he opens his eyes to questioning, he responds inappropriately and he withdraws when you pinch his hand. What is his GCS? a) 8 b) 10 c) 12 d) 14

Answer D

60. At what respiratory volume or capacity is PVR the lowest? a) RV b) TLC c) VC d) FRC

ANSWER: D (Consensus D) This is the classic teaching around Parkinson Disease. If this was an EXCEPT question, would choose A. Background: Parkinson Disease (PD) is a denegerative CNS disease caused by a loss of dopaminergic cells in the basal ganglia of the brain. The clinical effects are caused by dopamine deficiency. The classic triad of major signs includes skeletal muscle tremor, rigidity, and akinesia. Oral levodopa can be administered approximately 20 min before induction of anesthesia, and the dose may be repeated intraoperatively and postoperatively via an orogastric or nasogastric tube as needed. (Miller Pg 1198) Therapy for PD should be initiated preoperatively and be continued through the morning of the surgical procedure; such treatment seems to decrease drooling, the potential for aspiration, and ventilatory weakness. (Lange Pg 619) Medication for PD should be continued perioperatively, including the morning of surgery. The half- life of levodopa is short. Abrupt withdrawal of levodopa can cause worsening of muscle rigidity and may interfere with ventilation. (Barash) The half-life of levodopa is short and interruption in therapy for more than 6 to 12 hours can result in severe skeletal muscle rigidity that interferes with ventilation. Regarding A: PD is not a contraindication to epidural. Regarding B: PD is not usually associated with prolonged post-operative ventilation. The main issue is potential upper airway obstruction. (Barash) Perioperative respiratory complications are common. Upper airway obstruction may be a result of poor coordination of upper airway muscles secondary to neurotransmitter imbalance. Some patients with upper airway obstruction may respond favourably to anti-Parkinson medications. Regarding C: Severe Parkinson's Disease is listed as causing succinylcholine-induced hyperkalemia but this is seemingly rare and associated with severe disease. Therefore, not as true an answer as Option D. (Coexisting) The choice of a muscle relaxant is not influenced by the presence of Parkinson's disease. (Barash Pg 543) There have been isolated reports of hyperkalemia after succinylcholine in several neurologic diseases, including Friedrich's ataxia, polyneuritis, and Parkinson's disease.

61. You have a patient with Parkinson's disease who will be undergoing a whipple procedure, which of the following should you ensure? a) Avoid an epidural in this patient b) Anticipate prolonged post-operative ventilation c) Succinylcholine on induction is contra-indicated d) Give the patient's regular levodopa through NG during the procedure

ANSWER: A (Consensus A) TLDR Increased mineralocorticoid activity = hypokalemia + hypertension Increased glucocorticoid activity = HTN, muscle weakness, hirsutism Background on Adrenal Gland: (Lange Ch 34 Pg 738-9) § Cortex: androgens, mineralocorticoids (eg aldosterone), glucocorticoids (eg cortisol) • Aldosterone: fluid + electrolyte balance (fluid retention, $K, metabolic alkalosis) ∼ Na+ reabsorption in exchange for K+ and H+ ions • Glucocorticoids: multiple effects, including enhanced gluconeogenesis + inhibition of peripheral glucose utilization " results in #BG + worsen diabetic control ∼ Required for vascular + bronchial smooth muscle to respond to catecholamines ∼ Structurally related to Aldosterone " promote Na retention + K excretion § Medulla: catecholamines (primarily epinephrine, but also small amounts NE + dopamine) - Mineralocorticoid Excess § Primary: unilateral adenoma (aldosteronoma or Conn syndrome), bilateral hyperplasia, or carcinoma of adrenal gland § Secondary: stimulation of RAAS - CHF, hepatic cirrhosis w/ ascites, nephrotic syndrome, HTN (renal artery stenosis) § Clinical manifestations: • Hypokalemia • Hypertension - Glucocorticoid Excess § Exogenous steroid hormones, intrinsic hyperfunction of adrenal cortex (adrenocortical adenoma), ACTH production by nonpituitary tumour, hypersecretion by pituitary adenoma (Cushing's disease) § Clinical manifestation = Cushing's syndrome: • Muscle wasting + weakness • Osteoporosis • Central obesity • Moon facies • Abdominal striae • Glucose intolerance • Women: menstrual irregularity, acne, hirsutism • HTN • Mental status changes • Osteoporosis

66. ALL EXCEPT one of the following clinical manifestations are of hyperadrenalism. Indicate the exception? a) Hyperkalemia b) Hypertension c) Muscle Weakness d) Hirsutism

ANSWER: B (Consensus B) This question would be more clear-cut if it said definitely apnea but I guess can interpret "obtunded" and "likely narcotic overdose" to follow the higher dose as described by Cote PALS drug dosing says for full reversal: • <5 y or ≤ 20 kg: 0.1 mg/kg IV/IO/ET • ≥ 5 y or > 20 kg: 2 mg IV/IO/ET Note that it also comments to "use lower doses to reverse respiratory depression associated with therapeutic opioid use (1-5 mcg/kg titrate to effect)" Cote Pg 147: • For children who are ventilating and not in extremis but in whom opioid-induced respiratory depression needs antagonism in the perioperative period: o Can start with small dose of IV naloxone (0.25-0.5 μg/kg) o If response inadequate, can repeat same dose until ventilation improves o Same cumulative total IV dose can then be administered as IM injection to ensure recrudescence of respiratory depression does not occur • For children in extremis or potential opioid overdose has occurred (including neonatal resuscitation): larger dose of 10-100 mcg/kg IV may be indicated • American Academy of Pediatrics: (same as PALS) o Dosing for infants + children up to 5 yo " 100 mcg/kg o Children > 5 yo (>20 kg) " 2 mg naloxone

67. 3 year old infant who is obtunded from a likely narcotic overdose. Patient weighs 20kg. What is the dose of naloxone? a) 0.01mg/kg b) 0.1mg/kg c) 0.4mg/kg d) 0.02mg/kg

ANSWER: D (Consensus D) Reference: Barash ch. 11 p. 274 » Zone 3 occurs in the most gravity-dependent areas of the lung where Ppa > Ppv > PA and blood flow is primarily governed by the pulmonary arterial to venous pressure difference. » Zone 2 occurs from the lower limit of Zone 1 to the upper limit of Zone 3, where Ppa > PA > Ppv. The pressure difference between pulmonary artery and alveolar pressure determines blood flow in Zone 2. Pulmonary venous pressure has little influence. Well-matched ventilation and perfusion occur in Zone 2, which contains the majority of alveoli. » Zone 1 receives ventilation in the absence of perfusion. This relationship is referred to as alveolar dead space ventilation. Normally, Zone 1 areas exist only to a limited extent. However, in conditions of decreased pulmonary artery pressure, such as hypovolemic shock, Zone 1 enlarges, thus increasing alveolar dead space ventilation

68. With regards to West Zone physiology, which of the following is true? a) Increased tidal volume in West Zone 1 will increase physiological shunt b) Blood blow through West Zone 2 is intermittent with diastolic pulsations c) Can't remember d) Blood flow through West Zone 3 is dependent on arterial and venous pressure difference

ANSWER: C (Consensus C) Repeat Resp MCQ #10 (2011) + Cardiac #97 (2014) TLDR Normal PVR: mean PAP does NOT increase until CO has increased 2-2.5 X Elevated PVR (pulm HTN): mean PAP increases linearly w/ increasing CO b/c fixed PVR Additional problems arise in considering the pulmonary vasculature and using the formulas as a measure of resistance to flow through the lung. The pulmonary vasculature is more compliant than the systemic vasculature, and marked increases in pulmonary blood flow may not produce any significant increase in pulmonary artery pressure. In addition, flow usually ceases at end-diastole in the low resistance pulmonary circuit. Thus, changes in pulmonary vascular resistance may result from intrinsic alterations in pulmonary vascular tone (constriction or dilation), vascular recruitment, or rheologic changes. (Miller ch. 45 p. 1383) PHTN (assume fixed PVR). PVR = (MPAP - PAWP) / CO x 80. If CO rises, PAP will have to increase proportionally along with it to keep PVR constant. One of the most important factors in the evaluation of a patient scheduled for thoracic surgery is the presence of an increase in pulmonary vascular resistance secondary to a fixed reduction in the cross-sectional area of the pulmonary vascular bed. The pulmonary circulation is normally a low-pressure, high-compliance system capable of handling an increase in blood flow by recruitment of normally underperfused vessels. This acts as a compensatory mechanism that normally prevents an increase in pulmonary arterial pressure. In COPD, there is distention of the pulmonary capillary bed with decreased ability to tolerate an increase in blood flow (decreased compliance). Such patients demonstrate an increase in pulmonary vascular resistance when cardiac output increases because of a decreased ability to compensate for an increase in pulmonary blood flow.

69. In patients with pulmonary hypertension, the relationship of the mean pulmonary artery pressure with respect to cardiac output is the following. Which is true? a) There is no change until the cardiac output increases two-fold b) It is fixed despite changes in cardiac output c) It increases linearly with cardiac output d) It only increase with very high cardiac output

ANSWER: A (Consensus A) References: Barash pg 1018, Miller Chapter 81 pg 2448, Brain Trauma guidelines 3rd (pg 21) and 4th edition (pg 36 full edition, pg 3 summary) • The answer choice is most likely referring to the Saline versus Albumin Fluid Evaluation (SAFE) study, resuscitation with albumin is associated with higher mortality rate and unfavourable outcomes in TBI patients (Barash pg 1017) • Miller chapter 70 pg 2173-2174 quotes the same study, however critiques the conclusion of the study noting that the study was not appropriately randomized, 4% albumin solution used is hypoosmolar and expected to cause cerebral edema, and there is no physiological albumin hazard explanation. Miller concludes by saying "at best, the existing literature may justify considerations of limiting albumin volumes in patients with severe head injury" (Miller Chapter 70 pg 2173/2174) Regarding B • Succinylcholine is not contraindicated in patients with TBI, as the effects on ICP are clinically insignificant Regarding C The new 4th edition 2016 TBI guidelines do not recommend hypothermia. Barash provides reviews and trials of hypothermia being detrimental, however notes flaws in the trials and efficacy in experimental injury. He concludes that the value of hypothermia still remains to be established. Miller also provides the same reviews/trials but then discusses the current brain trauma foundation guidelines that prophylactic hypothermia is associated with better long term neurological outcomes but this is based off the previous third edition. Brain Trauma guidelines 4th edition 2016 • Early (within 48 hours), short term (48 hours post injury) prophylactic hypothermia is not recommended to improve outcomes in patients with diffuse therapy • No recommendations were given for > 48 hours • The previous third edition suggested preliminary findings of a greater decrease risk is observed when target temperatures are maintained for > 48 hours. Regarding D • Prolonged prophylactic hyperventilation with PaCO2 < 25 mmHg is not recommended • Hyperventilation should be avoided during the first 24 h after injury when CBF often is reduced critically • Hyperventilation is recommended as a temporizing measure for reduction of elevated ICP • (TBI guidelines 2016 summary pg 3) • Initial ventilation parameters should include 100%O2 arterial CO2 should be maintained in the lower normal range (35mmHg), and subsequent ventilation regimen should be guided by arterial blood gas analysis

7. In the management of a patient with a traumatic brain injury, which of the following is TRUE? a) Albumin is associated with increased mortality b) Succinylcholine is contraindicated c) Inducing moderate hypothermia is advantageous d) Brief hyperventilation to a PaCO2<25mmHg in the first 24hrs can improve outcome

ANSWER: B (Consensus B) Miller ch. 111 p. 3255 Sensitivity is, approximately, the ability of the test to detect the disease when truly present, and specificity indicates the ability of the test to avoid a false indication of the disease when truly absent. True positive (TP): The patient has disease, and the test is positive. False positive (FP): The patient does not have disease, and the test is positive. True negative (TN): The patient does not have disease, and the test is negative. False negative (FN): The patient has disease, and the test is negative. SENSITIVITY = True positive / (TP + FN = all people who truly have the disease) SPECIFICITY = True negative / (TN + FP = all people who truly do NOT have the disease)

70. Formula for Specificity a) True negative / (true negative + false negative) b) True negative / (true negative + false positive) c) True positive / (true positive + false negative) d) True negative / (true positive + false negative)

ANSWER: B (Consensus B) Reference: Barash ch. 41 p. 1208 Newborns born with myelomeningocele have an associated anomaly of the brainstem known as the Arnold-Chiari II (Chiari II) malformation. The Chiari II malformation is characterized by caudal displacement of the cerebellar vermis through the foramen magnum, caudal displacement of the medulla oblongata and the cervical spine, kinking of the medulla, and obliteration of the cisterna magna. The cause of Chiari II malformation rests in the small size of the skull housing the posterior fossa, forcing CNS contents out during development. Hydrocephalus requiring shunting develops in approximately 80% to 90% of infants with myelomeningocele. In contrast, only 20% of patients have symptoms of brainstem dysfunction as a result of the Chiari II malformation, but the mortality rate among those symptomatic patients is high. Complications of brainstem dysfunction include stridor, apnea and bradycardia, aspiration pneumonia, sleep-disordered breathing patterns, vocal cord paralysis, lack of coordination, and spasticity. If the symptoms are not improved by shunting, posterior fossa decompression is necessary. The infant with a myelomeningocele is usually operated on within the first 24 to 48 hours of life. This reduces the risk for development of ventriculitis or progressive neurologic deficits. Most centers close the defect and place a shunt at the same time. However, some centers may delay placement of a shunt until the infant shows symptoms of hydrocephalus. There is ongoing work to determine the benefits of intrauterine repair of myelomeningocele, hopefully with the benefits of decreased development of a Chiari II malformation, decreased hydrocephalus, and increased lower limb function. As these studies continue, the role of intrauterine repair will become clearer... In most instances, the infant has an intravenous line placed before surgery and an intravenous induction is performed. Succinylcholine may be used to facilitate intubation without risking hyperkalemia. Because increased intracranial pressure is rarely present before closure of the defect, inhalational induction is an alternative in the infant with difficult intravenous access.

71. Which of the following regarding myelomeningocele is the most correct? a) Commonly associated with high ICP b) Arnold chiari predisposes to brain stem compression c) Succinylcholine is likely to induce hyperkalemia d) Should be fixed within 2 weeks

ANSWER: D (Consensus D) Adjunctive use of a low-dose ketamine infusion (1 to 3 mcg/kg/min IV) during the 24 to 48 hour period after major surgery produces significant opioid-sparing effects and decreases opioid-related gastrointestinal side effects. (Barash ch. 18 p. 490) Over the years, the ketamine dose used for perioperative analgesia has gradually been decreasing. Ketamine administered in small doses decreases postoperative analgesic consumption by 33%. Several meta-analyses of the use of small-dose ketamine (20 to 60 mg) perioperatively have been performed. These meta-analyses showed an overall decrease in opiate use or improved analgesia and a decrease in opiate-induced side effects, especially PONV. Side effects, especially psychomimetic effects, were minimal, especially if a benzodiazepine also was administered. (Miller ch. 30 p. 849) Nonetheless, S-ketamine produces psychotropic effects, cognitive impairment, memory impairment, and a reduced reaction time, in addition to analgesia. (Miller ch. 30 p. 845)

72. Your patient undergoing a thoracotomy with a ketamine infusion as an adjunct for pain - which of the following side effects is expected? a) Nausea b) Pruritis c) Urinary retention d) Short term memory loss

ANSWER: F (Consensus A, 3E) DISAGREE with Consensus - more evidence for F vs A VLs with a distally angulated or highly curved blade permit a "look around the corner," providing an improved laryngoscopic view without requiring manipulation of the cervical spine. These devices are therefore of particular utility in patients with cervical immobilization, micrognathia, or limited mouth opening. The GlideScope (Verathon, Bothell, WA) is the prototype for this subset of devices. It possesses a 60-degree blade angulation, an antifogging mechanism, a 7-inch LCD monitor, and is available in reusable and single-use models. The McGrath Series 5 laryngoscope is a similar device in that it possesses a distally angulated blade; its primary difference is its greater portability and a disarticulating handle that can be useful in patients with limited mouth opening and limited movement of the head and neck. (Miller ch. 55 p. 1674) The 60-degree angulation of the GlideScope reduces cervical spine motion by 50% at the C2 to C5 segments compared with Macintosh laryngoscopy. Theoretically, the airway axes do not need to be aligned to affect a good view, but manipulation of the GlideScope to the position to achieve an adequate image can cause cervical segment extension. It has been successfully used to achieve tracheal intubation in patients with limited cervical spine movement because of ankylosing spondylitis and cervical spine arthritis, but it may be difficult to use in patients with limited oral aperture.

73. Which of the following is not an indicator of difficult glidescope intubation (answers remembered differently) a) Prominent teeth b) Abnormal anatomy c) Grade 3 view direct d) Limited mandibular protrusion e) Morbid obesity f) Limited neck movement

ANSWER: EXCEPT C (or D if actually is as written) (Consensus D, 4 C) The pharmacokinetics of rocuronium is not altered by obesity. In the same way, the duration of action of rocuronium is significantly prolonged when the dose is calculated according to TBW. In contrast, when rocuronium is dosed according to ideal body weight (IBW), the clinical duration is less than half. The finding that IBW avoids prolonged recovery of atracurium-induced blockade can be explained by an unchanged muscle mass and an unchanged volume of distribution in morbidly obese patients compared with normal-weight patients. The duration of cisatracurium is also prolonged in obese patients when the drug is given on the basis of TBW versus IBW. Nondepolarizing NMBDs should be given to obese patients on the basis of IBW rather than on their actual body weight, to ensure that these patients are not receiving relative overdoses and to avoid prolonged recovery. When 1using maintenance doses, objective monitoring is strongly recommended to avoid accumulation. (Miller ch. 34 p.986) Drugs with weak or moderate lipophilicity may be dosed on the basis of LBW. Adding 20% to the estimated IBW dose of hydrophilic medications is sufficient to include the obese patient's extra lean mass. Nondepolarizing muscle relaxants can be dosed in this manner. (Barash ch. 44 p. 1281) Consequently, commonly used anesthetic drug dosing is based on IBW for propofol, vecuronium, rocuronium and remifentanil. In contrast, doses of midazolam, succinylcholine, cisatracurium, fentanyl, and sufentanil should be determined on the basis of TBW. (Miller ch. 71 p. 2212)

74. Which muscle relaxant is dosed based on ideal body weight a) Cisatricurium b) Atricurium c) Succinylcholine d) Rocuronium

ANSWER: D (Consensus D) The LV coronary perfusion pressure is often defined as the gradient between the aortic diastolic (or mean) pressure and left ventricular diastolic pressure (LVDP, usually estimated by pulmonary artery occlusion pressure). In the presence of intraluminal obstruction or increased vascular tone, this pressure gradient is reduced. A low LVDP is ideal for improving perfusion (higher pressure gradient) and reducing MVO2 (decreased LV volume and wall tension). On the other hand, increasing perfusion pressure by raising the aortic pressure will increase MVO2. However, this is not as important, when one considers that tachycardia is the most important cause of intraoperative and perioperative ischemia. (Barash ch. 38 p. 1077)

75. Which parameter change is most responsible perioperative ischemia a) Bradycardia b) Ventricular volume increase c) LVEDP decrease d) Tachycardia

ANSWER: A (Consensus A) Repeat of Pharm MCQ #167 (2013) The mechanisms underlying the enhancement of nondepolarizing block by magnesium probably involve both prejunctional and postjunctional effects. High magnesium concentrations inhibit Ca2+ channels at the presynaptic nerve terminals that trigger the release of acetylcholine. Further, magnesium ions have an inhibitory effect on postjunctional potentials and cause decreased excitability of muscle fiber membranes. In patients receiving magnesium, the dose of nondepolarizing NMBDs must be reduced and carefully titrated using a nerve stimulator to ensure adequate recovery of neuromuscular function at the end of surgery. (Miller ch. 34 p 982)

77. What is the effect of magnesium on acetylcholine and neuromuscular transmission? a) Decreased release from presynaptic b) Increased sensitivity of junctional membrane to Acetylcholine c) Increased hyperreflexia d) Increased muscle excitability

ANSWER: B (Consensus B) In restrictive disease, the vital capacity (VC) is decreased and expiratory flow rate is increased (i.e., steeper than the normal slope of the forced expiratory curve). In COPD, the residual volume (RV) is increased, the VC is reduced, and forced expiration is slowed. ERV, Expiratory reserve volume; TLC, total lung capacity.

78. Which is reduced in both restrictive and obstructive lung disease? a) TLC b) VC c) RV d) FRC

ANSWER: B (Consensus B) Immediate replacement of the uterus, even before removal of the placenta, is the treatment goal, but it may be difficult to achieve. The appropriate technique for correcting an inversion has been described. All uterotonic drugs should be discontinued immediately. The obstetrician should attempt to right the inversion by applying pressure through the vagina to the uterine fundus; ring forceps may be used on the cervix to apply countertraction. Early diagnosis and prompt correction may reduce the morbidity and mortality associated with uterine inversion. Often, uterine tone precludes replacement of the uterus, and uterine relaxation is necessary for successful uterine reduction. The use of nitroglycerin to facilitate relaxation and replacement of the uterus has been reported. Fairly large intravenous doses (200 to 250 μg) may be required, and the anesthesiologist typically will need to support the circulation with intravenous fluids and vasopressors. Administration of general anesthesia with a volatile halogenated agent may become necessary, not only for uterine relaxation but also to prepare for laparotomy should it become necessary to correct the inversion. Once the uterus has been replaced, a firm, well-contracted uterus is desired. Oxytocin should be infused, and additional uterotonic drugs may be needed.

79. After a difficult placental delivery, a postpartum hemorrhage is diagnosed, with hypotension and bradycardia. What is the appropriate immediate management? a) Oxytocin 10U bolus b) Manual uterine reduction c) Nitroglycerin 100ug d) General anesthesia with volatile anesthetic

ANSWER: A (Consensus A) References: http://stroke.ahajournals.org/content/5/3/303.short http://www.nejm.org/doi/full/10.1056/NEJMra041544 This question is similar to Cardiac section Q9 except option C has changed from transient global amnesia from transient global ischemia. The answer is most likely A based off NEJM Vertebrobasilar Disease, neurology resident discussion, and further internet sources. Miller, Barash, CoE do not help. Answer A - Amaurosis Fugax • Atherostenosis at or near the origin of vertebral artery in the neck is often manifested as brief TIAs, consisting of dizziness, difficulty focusing visually, and loss of balance (NEJM) • Presumably then amaurosis fugax (temporary painless vision loss in one or both eyes) is a symptom of TIAs. • However, amaurosis fugax is most commonly results from an atherosclerotic internal carotid artery (and then emboli to its branches - ophthalmic, retinal), which is the anterior circulation (internal carotids) of brain and not the posterior circulation (vertebral). Regarding C Transient global amnesia • According to AHA/Stroke (1974) "It is concluded that the majority of transient global amnesic episodes in the elderly or in those with the risk factors listed above result from cerebrovascular insufficiency particularly in the territory of vertebrobasilar and posterior cerebral arterial systems (which supply major portions of the ascending reticular activating system, parahippocampal-fornical-mamillary system, inferomedial aspects of the temporal lobe and occipital lobe)" • Transient global amnesia is a neurological disorder whose key defining characteristic is a temporary but almost total disruption of short term memory with a range of problems assessing older memories (Wikipedia) • According to NEJM when emboli results in someone with veterbrobasilar disease a potential symptom is the "Inability to make new memories as well as an agitated sate can also occur" (NEJM) • According to case report in clinical neuroscience "The vertebrobasilar system may play a role in TGA "A case of transient global amnesia"

8. Which of the following is NOT an indication of vertebrobasilar atheromatous disease? a) Amaurosis fugax b) Postural hypotension c) Transient global amnesia d) Diplopia

ANSWER: A (Consensus A) Kava can act as a sedative-hypnotic by potentiating inhibitory neurotransmitters of GABA (Kava rhymes with GABA!)

80. Which of the following herbal medications provides sedation and anxiolysis through the GABA receptor? a) Kava b) Saw Palmetto c) Ginseng d) Gingko biloba

ANSWER: A (Coexisting ch. 13 p. 281) Cirrhotic patients with portopulmonary hypertension have a very limited life expectancy. Liver transplantation is the only known curative therapy, but it can be recommended only if pulmonary vascular resistance is not severely increased. (Barash ch. 45 p. 1309)The role of liver transplantation in the treatment of PPHTN is not well defined, because outcomes of transplantation are not predictable. Some patients have resolution of PPHTN with transplant, some may have no or incomplete resolution and continue to require medical therapy, and some may experience worsening of their PPHTN. Regarding B: peripheral edema is NOT part of the score Regarding C: (Barash ch. 45 p. 1307) Although profound renal vasoconstriction is the proximate cause of HRS, therapy aimed at directly increasing renal perfusion by the use of prostaglandins, dopamine agonists, or endothelin antagonists has not proved successful. Regarding D: (Barash ch. 45 p. 1316) Modified Child score performed similarly in predicting perioperative mortality. Child's class A was associated with 10%, Child's B with 30%, and Child's C with greater than 80% mortality. The 3-month mortality for hospitalized patients not undergoing surgery was 4% for class A, 14% for class B, and 51% for class C.

81. Which of the following is true concerning liver disease a) Liver transplantation is the only cure for portopulmonary hypertension b) Child-Pugh classification involves bilirubin, albumin, INR, ascites and peripheral edema c) Hepatorenal syndrome results from renal vasodilation d) Child-Pugh C is has a perioperative mortality of approximately 30% for intraabdominal surgery (other submitted answer said 40%)

ANSWER: A (Consensus A) Some of the initial changes in hemodynamics associated with cross-clamping can be offset by boluses of a vasodilator administered immediately before placement of the clamp (e.g., nitroprusside 0.3 to 0.7 mcg/kg, nicardipine 200 to 600 mcg, or milrinone 50 mcg/kg over 10 minutes). In this case, mechanical and pharmacologic actions cancel out each other while the body is allowed to adapt. (Barash ch. 39 p. 1134) Supraceliac aortic cross-clamping increases mean arterial pressure by 54% and pulmonary capillary wedge pressure by 38%. Ejection fraction, as determined by two-dimensional echocardiography, decreases by 38%. Despite normalization of systemic and pulmonary capillary wedge pressure with anesthetic agents and vasodilator therapy, supraceliac aortic cross- clamping causes significant increases in left ventricular end-systolic and end- diastolic area (69% and 28%, respectively), as well as wall motion abnormalities indicative of ischemia in 11 of 12 patients. Aortic cross-clamping at the suprarenal level causes similar but smaller cardiovascular changes, and clamping at the infrarenal level is associated with only minimal changes and no wall motion abnormalities. (Miller ch. 69 p. 2119) Patients requiring supraceliac aortic cross-clamping have significant increases in end-diastolic area and significant decreases in ejection fraction on echocardiography that are not completely normalized with vasodilators and frequently are not detected by pulmonary artery catheter monitoring.

82. Patient with ischemic mitral regurgitation come for an AAA repair. After placement of the supra celiac clamp you note the tricuspid regurgitation velocity increases from 3 to 4m/s, what is the most appropriate treatment? a) Nitroprusside b) Metoprolol c) Enalaprit d) Vasopressin

ANSWER: B (Consensus B) The following are required: » Pulse oximeter » Apparatus to measure blood pressure, either directly or non-invasively » Electrocardiography » Capnography for general anesthesia and sedation (RSS 4-6) » Agent-specific anesthetic gas monitor, when inhalation anesthetic agents are used

83. You are asked to assist with procedural sedation for ERCP. Which of the following is in keeping with CAS guidelines for out of OR procedural sedation? a) presence of a trained AA b) use of continuous capnography c) full access to patient d) gas machine with full piping and scavenging

ANSWER: C (especially if question was actually asking about the "Ca Release Unit") (Consensus C) (P+P PDF Pg 567) There are 2 types of calcium channels, dihydropyridine receptor (DHPR) in the T-tubules and the ryanodine receptor (RyR1) in the sarcoplasmic reticulum. DHPRs act as "voltage sensors" and are activated by membrane depolarization, which in turn activate RyR1 receptors. DHPR-RyR1 interaction releases large amounts of Ca2+ from the SR that result in transient increase in myoplasmic free Ca2+. (Miller Ch 43 Pg 1290) The elemental unit of function has been named the Ca2+ release unit (CRU) and it is localized within junctional regions of T-tubule and SR membranes. The CRU is a macromolecular assembly of interacting proteins that participate in tightly regulating EC coupling. RyR1 is a high-conductance channel that regulates the release of SR Ca2+ and is the central component of the CRU. The functional RyR1 tetramer anchored within the SR membrane physically spans the junctional space to interact with tetrads made up of 4 voltage-activated CaV1.1 subunits within the T-tubule membrane. This physical interaction engages a form of bidirectional signalling that tightly regulates the function of both proteins. Between 50% and 80% of genotyped patients who have had a clinical MH syndrome and a positive muscle biopsy have had their disease linked to 1 of more than 210 mutations in the type 1 ryanodine receptor (RyR1; sarcoplasmic reticulum [SR] Ca2+ release channel) gene and 4 mutations in the pore subunit of the slow inactivating L-type Ca2+ channel CaV1.1 (dihydropyridine receptor [DHPR]). The genetics of MH and the related abnormal function of RyR1, the DHPR, and associated proteins are being investigated at the molecular biologic level. Invaginations of the surface membrane (transverse or T tubules) act as conduits to direct action potentials rapidly and uniformly deep within the myofibrils where they transduce a conformational change in the voltage sensor integral to CaV1.1. Conformational changes in CaV1.1 are mechanically transmitted to the Ca2+ release channels (RyR1) residing in the junctional face of the SR. The mechanical coupling of DHPRs and RyR1 channels that occurs at specialized junctions (triadic junctions) is essential for linking the electrical signals arriving at the T tubules with the release of Ca2+ stored within the SR. Release of SR Ca2+ causes the free, cytoplasmic (sarcoplasmic) Ca2+ concentration to increase from 10−7 μM to approximately 10−5 μM. The Ca2+ binds to contractile proteins (troponin C and tropomyosin) in the thin filament to expose the myosin-binding sites on actin that activate the thick filament (myosin) and cause a shortening of the muscle fibers (i.e., muscle contraction). The entire process is termed excitation-contraction (EC) coupling.

84. Which of the following is true of the calcium receptor unit? a) It contains a central protein subunit CaV1.1 b) single protein in plasma membrane c) participates in the excitation-coupled response d) the alternative name is the ryanodine receptor

ANSWER: C (Consensus C) Repeat of Regional MCQ #31 (2011) Oxycodone is mainly a prodrug, becoming active after conversion by the enzyme cytochrome P450 2D6 to oxymorphone (a mu-opioid agonist). Noroxycodone is its inactive metabolite. It has a high bioavailability (60%) and is associated with a low incidence of itching and hallucinations. It has an NNT of 2.5 in neuropathic pain; the oxycodone-to-morphine ratio is 1:1.5. (Barash ch. 57 p. 1660) The clinical pharmacology of the fentanyl congeners is not grossly altered by renal failure, although a decrease in plasma protein binding potentially can alter the free fraction of the fentanyl class of opioids. Fentanyl clearance is not altered by renal failure. As with fentanyl, sufentanil pharmacokinetics are not altered in any consistent fashion by renal disease, although greater variability exists in the clearance and elimination half-life of sufentanil when patients have impaired renal function. An increased clinical effect is likely with alfentanil in renal failure because of a decreased initial volume of distribution and an increased free fraction of alfentanil. No delay in recovery after alfentanil administration should be expected, however. Neither the pharmacokinetics nor the pharmacodynamics of remifentanil are altered by impaired renal function. Hydromorphone, as the parent drug, does not substantially accumulate in hemodialysis patients. Conversely, an active metabolite, hydromorphone- 3-glucuronide, quickly accumulates between dialysis treatments, but seems to be effectively removed during hemodialysis. With careful monitoring, hydromorphone can be used safely in patients who require dialysis. It should be used with caution, however, in patients with a GFR less than 30 mL/min and who have yet to start dialysis or who have withdrawn from dialysis.

85. Which of the following will accumulate the least in a patient with renal failure? a) Morphine b) Hydromorphone c) Fentanyl d) Oxycodone e) Codeine

ANSWER: D (Consensus D) Most of the intravenous induction agents have been used for ECT. Methohexital (1 to 1.5 mg/kg) is considered the "gold standard". Etomidate (0.15 to 0.3 mg/kg) is generally associated with longer seizure duration and is the preferred agent of some psychiatrists, despite a slightly longer recovery and associated myoclonus. Propofol (an anticonvulsant) is more effective at attenuating the acute hemodynamic responses than etomidate and in small doses (0.75 mg/kg) seizure duration is usually acceptable.

86. Which of the following IV induction agents prolongs seizure duration in ECT? a) Ketamine b) Methohexital c) Propofol d) Etomidate

ANSWER: C (Consensus C) Virtually all components of the cardiovascular system are affected by the aging process. The major changes include (1) decreased response to β-receptor stimulation; (2) stiffening of the myocardium, arteries, and veins; (3) changes in the autonomic nervous system with increased sympathetic activity and decreased parasympathetic activity; (4) conduction system changes; and (5) defective ischemic preconditioning. The majority of cases of congestive heart failure in very old persons are due to diastolic dysfunction and occur in the absence of clinically significant systolic dysfunction. (Barash ch. 33 p. 897) The aged kidney does not eliminate or retain sodium when necessary as effectively as that of a young adult. Part of the failure to conserve sodium when appropriate may be because of reduced aldosterone secretion. Similarly, the aged kidney does not retain or eliminate free water as rapidly as young kidneys when challenged by water deprivation or free water excess. Aging also results in less-effective coughing and impaired swallowing. Aspiration is a significant cause of community-acquired pneumonia and may well play a role in the development of postoperative pneumonia. (Barash ch. 33 p. 898) Chronic pain occurs in 25% to 50% of community-dwelling older persons. Age is an important predictor of postoperative morphine requirements, with older patients needing less drug for pain. Morphine and its metabolite morphine-6-glucuronide have analgesic properties. Morphine clearance is decreased in older adults. (Miller ch. 80 p. 2417)

87. In an elderly patient, which of the following increases their perioperative risk? a) Decreased LV systolic function is the most common cardiac changes b) The neuroendocrine response to stress results in decreased sensitivity to vasopressin and decreased water retention c) Decreased cough reflex results in increased risk of aspiration d) Elderly patients are less at risk of chronic post-op pain

ANSWER: B (Consensus B) PaO2 goal is > 55 and PEEP should be >18 with FiO2 100% PaCO2 goal is pH 7.30 - 7.45, achieved first by increasing RR to 35 and then increasing Vt by 1 mL/kg increments only if pH < 7.15.

88. Patient with ARDS, TV 6ml/kg, Peep 16 Plateau pressure 25, Fi02 100%, Blood gas shows pH 7.2, PaC02 60, Pa02 48, HC03 30, what should be done with the ventilation? a) Increase TV to 8mL/Kg b) Increase PEEP c) ECMO d) HFO

ANSWER: A (Consensus A) Cycling from the inspiratory to the expiratory phase in PSV occurs when inspiratory flow rate decreases to a preset level.

89. PSV - what variable is used to cycle from inspiration to expiration? a) Flow b) Pressure c) Time d) Volume

ANSWER: D (Consensus D) Reference: Miller Chapter 31 pg 876 • Opioids can cause increased muscle tone and may cause muscle rigidity. • Vocal cord closure is primarily responsible for difficult ventilation with bag mask that follows administration of opioids • Delayed postoperative rigidity is probably associated related to second peaks that can occur in plasma opioid concentrations, similar to the recurrence of respiratory depression.

9. You are going to induce general anesthesia for a 15 minute procedure and want to avoid Succinylcholine. Which of the following is TRUE regarding the use of short acting opioids instead of neuromuscular blockers for induction? a) Decreased rate of failed intubation b) Improved hemodynamic stability c) Less laryngeal trauma d) Increased rate of difficult bag mask ventilation

ANSWER: B (Consensus B) Reference: Cote Pg. 664-665, Miller Ch. 93 Pg.2795, Barash Pg. 1362 Answer: B - Unable to tolerate PO = FALSE (according to Barash): Miller echoes the same concerns as Cote: " In general, risk factors for postoperative complications include: • age < 3 years • abnormal coagulation values • evidence of OSA • systemic disorders that place the child at increased perioperative risk (cor pulmonale, metabolic diseases) • Presence of craniofaial or other airway abnormalities • Performance of the procedure for peritonsillar abscess • child living a long distance from an adequate health care facility, adverse weather conditions, or home conditions not consistent with close observation, cooperativeness, and ability to return quickly to the hospital (eg. substance abusing parents, teenage mother). • Obesity (>95% BMI or >95% weight for gender and age) • African-American ethnicity" Miller does not state these are absolute indications for admission though, and follows up with a discussion of how difficult it is for anesthesiologists to decide when it is safe to send the children home, and what to use for post- operative analgesia. Miller also does not mention inability to tolerate PO intake, though this doesn't really have much of a place in his discussion. Presumably an inability to tolerate PO intake is a reason to watch the child until they can tolerate it, not an automatic admission. Barash: RE: A- Down's = TRUE: Falls under the "craniofacial abnormalities" category in Table 31-5 from Cote/Barash table. RE: B - Unable to tolerate PO = FALSE: Depending on the source you read, this could be considered an indication for admission. Cote is explicit in saying it is, Miller does not mention it, and Barash is explicit in saying that it is not. I am assuming the source of this question is Barash, as all of the other options are universally agreed upon indications for admission. Barash: "Patients should be observed for early hemorrhage for a minimum of 4 to 6 hours and be free from significant nausea, vomiting, and pain prior to discharge. The ability to take fluid by mouth is not a requirement for discharge home. However, intravenous hydration must be adequate to prevent dehydration. Excessive somnolence and severe vomiting are indications for hospital admission. There are patients for whom early discharge is not advised, and those patients should be admitted to the hospital after tonsillectomy. The characteristics of such patients are listed in Table 47-1. Admission to an ICU is controversial and reserved for those children with very severe OSA, comorbidities that cannot be managed on the floor, and children who have demonstrated significant airway obstruction and desaturation in the initial postoperative period that required intervention beyond repositioning and oxygen supplementation." RE: C - Bleeding diathesis = TRUE: Falls under the "documented coagulopathy" category. RE: D - Severe OSA = TRUE: Cote: "Children younger than 3 years of age and those with complex medical disorders are not candidates for adenotonsillectomy as outpatients. Although children undergoing adenotonsillectomy for obstructive breathing without apnea may undergo ambulatory surgery, those with OSA should not. A diagnosis of OSA increases the likelihood of respiratory complications after adenotonsillectomy from 1% in otherwise healthy children to 20% in those with OSA."

90. All need admission post tonsillectomy except: a) Down's b) Unable to tolerate PO c) Bleeding diathesis d) Severe OSA

ANSWER: B (Consensus B) Reference: Barash Pg. 243, 277 Answer: B - Coronary Sinus = FALSE: The coronary sinus is the termination of the coronary veins, and empties into the posterior aspect of the right atrium, above the tricuspid valve. Approximately 85% of the total coronary blood flow to the LV drains into the coronary sinus. The remaining blood flow empties directly into the atrial and ventricular cavities via the Thebesian veins (see answer A). The RV veins drain into the anterior cardiac veins; these empty individually into the right atrium. RE: A - Thebesian veins = TRUE: The Thebesian (not thespian = actor) veins drain from the arteries supplying the cardiac chambers into the chambers themselves. As such, the left sided thebesian veins would contribute to physiologic shunt, as the blood flow pattern would be oxygenated blood from the aorta, into the coronary arteries, draining deoxygenated blood back into the left heart. Physiologic shunt is the portion of total cardiac output that returns to the left heart and systemic circulation without receiving oxygen in the lung. A small percentage of venous blood normally bypasses the right ventricle and empties directly into the left atrium. This anatomic, absolute, or true shunt arises from the venous return of the pleural (Option D), bronchiolar (Option C), and Thebesian (Option A) veins. This venous admixture accounts for 2-5% of total cardiac output and represents the small shunt that normally occurs.

91. All of the following contribute to the physiologic shunt EXCEPT a) Thespian veins b) Coronary sinus c) Bronchial veins d) Pleural veins

ANSWER: B (Consensus B) References: Table 3 2007 ACC/AHA guidelines on the prevention of infective endocarditis, Kaplan Ch. 20 Pg. 620 Answer: B - Secundum ASD = FALSE: This is not a cyanotic lesion, therefore it does not require IE prophylaxis. A secundum ASD is an ASD that is usually adjacent to the foramen ovale. It would result in a left to right shunt (acyanotic lesion) until such a point that RA pressure exceeds LA pressure, resulting in flow reversal and a cyanotic Right to Left shunt (Eisenmenger's Syndrome). Kaplan specifically discusses secundum ASDs, which are the most common type of ASD, and states that "An otherwise uncomplicated secundum ASD, unlike most congenital cardiac defects, is not associated with an increased endocarditis risk. Presumably, this is because the shunt, although potentially large, is low pressure and unassociated with jet lesions of the endocardium." Note, however, that the AHA guidelines are not based on an increased risk of developing endocarditis, but instead an increased risk of adverse outcome from endocarditis. (eg. Mitral Vale prolapse is the most common condition that predisposes to acquisition of IE in the western world, but the absolute incidence is very low, and outcome is not as bad as for the conditions listed in Table 3, therefore prophylaxis is not recommended.) RE: A - Patch repair done 3 months ago = TRUE: Any repaired congenital heart disease requires IE prophylaxis for 6 months following the procedure, as this is the length of time required for endothelialization to occur. RE: C - Previous IE = TRUE: It is one of the 6 conditions that warrants IE prophylaxis because these individuals are at the highest risk of developing adverse outcomes from infectious endocarditis. RE: D - Previous valve replacement = TRUE: Presence of a prosthetic cardiac valve is another of the 6 conditions that are at the highest risk for developing adverse outcomes from infective endocarditis, and as a result warrant IE prophylaxis with antibiotics.

92. All of the following require IE prophylaxis EXCEPT a) Patch repair done 3 months ago b) Secundum ASD c) Previous IE d) prevoius valve replacement

ANSWER: C (Consensus C) References: Kaplan Ch. 12 Pg 332, Miller Ch. 46 Pg 1410, Barash Pg. 728 Answer: C - Hiatal Hernia = FALSE: This questions seems to come from Barash, which lists off all of these options except for Hiatus hernia. Out of Barash, Miller, and Kaplan, only Barash mentions Zenker's diverticulum specifically (others mention diverticula generically). Kaplan does mention a symptomatic hiatal hernia as a relative contraindication. RE: A - Active GI Bleed/Varicele bleed = TRUE: All textbooks agree that this is a contraindication, with Miller including esophageal hemorrhage as an absolute contraindication to TEE placement. RE: B - Zenker's Diverticulum = TRUE: While only Barash mentions a Zenker's diverticulum, all other texts include esophageal diverticula in general as a contraindication to TEE placement. Regardless, they all agree that esophageal diverticula = a no-go. RE: D - Esophageal Web = TRUE: All textbooks have a bit of a motherhood statement describing esophageal abnormalities in general before listing their contraindications specifically. Barash is the only one who mentions webs explicitly. The question may arise: Barash mentions GI bleed, Zenker's Diverticulum and Esophageal webs, whereas Kaplan mentions GI bleed, Diverticula, and Hiatal hernias, and both are Royal College textbooks... why chose option C (Hernia) over option D (Web)? I chose C over D because Barash is explicit in the paragraph where he lists Zenker's diverticula (making it more likely that this question came specifically from that source). In addition, Kaplan states symptomatic hiatal hernias are a relative contraindication, and Miller has a generic statement about 'severe esophageal obstruction' being one of the contraindications, which you could argue for a web representing an esophageal obstruction (and maybe a severe one at that). Kaplan: "Absolute contraindications to TEE in intubated patients include esophageal stricture, diverticula, tumor, recent suture lines, and known esophageal interruption. Relative contraindications include symptomatic hiatal hernia, esophagitis, coagulopathy, esophageal varices, and unexplained upper gastrointestinal bleeding. Notably, despite these relative contraindications, TEE has been used in patients undergoing hepatic transplantation without reported sequelae." Miller: "Absolute contraindications include prior esophagectomy, severe esophageal obstruction, esophageal perforation, and ongoing esophageal hemorrhage. Relative contraindications include esophageal diverticulum, varices, fistula, and prior esophageal surgery, as well as a history of a gastric surgery, mediastinal irradiation, unexplained swallowing difficulties, and other conditions that might worsen with the placement and manipulation of the TEE probe." Barash: "Contraindications to TEE probe placement are represented by esophageal stricture, rings or webs, esophageal masses (especially malignant tumors), recent bleeding of esophageal varices, Zenker's diverticulum, status post radiation to the neck, and recent gastric bypass surgery."

93. All of the following are contraindications to TEE EXCEPT a) active GI bleed/Varicele bleed b) Zenkers Diverticulum c) Hiatal hernia d) esophageal web

ANSWER: C (Consensus C) References: Miller Ch. 38 Pg. 1110, 1112, Barash Pg. 1032-1033 (likely question source) Answer = C - ECG shows an enlarged p wave in precordial leads and signs of LVH = FALSE: You would see an enlarged P wave, or P Pulmonale, but this is typically seen in leads II, III, aVF, and V1; not in all precordial leads. Signs of LVH are not expected, as there is increased afterload to the right heart owing to chronic hypoxemia leading to the development of pulmonary hypertension. In discussing ECG changes of COPD, Miller states: "Right axis deviation, RBBB, or peaked P waves on an ECG suggest right ventricular changes and pulmonary hypertension." In discussing ECG changes suggestive of pulmonary hypertension, Miller states: "An ECG and a chest radiograph are useful in patients with more than mild disease. Typical ECG findings include right axis deviation, RBBB, right ventricular hypertrophy, and tall R waves in leads V1 and V2. Right atrial hypertrophy and "P-pulmonale" may be present in severe pulmonary hypertension, with peaked P waves, usually in leads II, III, aVF, and V1." From Barash: "A patient with COPD may present with electrocardiographic features of right atrial and ventricular hypertrophy and strain. These include a low-voltage QRS complex due to lung hyperinflation and poor R-wave progression across the precordial leads. An enlarged P wave ("P pulmonale") in standard lead II is diagnostic of right atrial hypertrophy. The electrocardiographic changes of right ventricular hypertrophy are an R/S ratio of greater than 1 in lead V1 (i.e., R-wave voltage exceeds S-wave voltage)." RE: A - ABG in chronic bronchitis shows hypercarbia and hypoxemia = TRUE: Barash: "A common finding in arterial blood gas analysis of patients with COPD is hypoventilation and CO2 retention. The "blue bloaters" (chronic bronchitis) are cyanotic, hypercarbic, hypoxemic, and usually overweight. They are in a state of chronic respiratory failure and have a decreased ventilatory response to CO2." Contrast this with: "The "pink puffers" (patients with emphysema) are typically thin, dyspneic, and pink, with essentially normal arterial blood gas values. They present with an increase in minute ventilation to maintain their normal Paco2, which explains the increase in work of breathing and dyspnea." RE: B - Auscultating heart sounds reveals a narrowly split second heart sound from pulmonary hypertension = TRUE: From Miller discussing signs of pHTN: "Physical examination may reveal a split S2 with a loud second component, right ventricular heave, tricuspid regurgitation murmur, ascites, hepatomegaly, jugular venous distention, and peripheral edema." Barash: "In COPD, there is distention of the pulmonary capillary bed with decreased ability to tolerate an increase in blood flow (decreased compliance). Such patients demonstrate an increase in pulmonary vascular resistance when cardiac output increases because of a decreased ability to compensate for an increase in pulmonary blood flow. This results in pulmonary hypertension, signs of which include a narrowly split second heart sound, increased intensity of the pulmonary component of the second heart sound, and right ventricular and atrial hypertrophy." RE: D - CXR (AP) Lateral shows hyperinflation and large retrosternal air space = TRUE: Barash: "Hyperinflation and increased vascular markings are usually present with COPD. Prominent lung markings often occur in bronchitis they are decreased in emphysema, particularly at the bases, where actual bullae may be present in severe cases. Hyperinflation, with an increased anteroposterior chest diameter, may be present, together with an enlarged retrosternal air space of >2 cm in diameter seen in a lateral chest radiograph."

94. ALL EXCEPT one of the following investigation or physical exam findings are true about COPD. Indicate the exception? a) ABG in chronic bronchitis shows hypercarbia and hypoxemia b) Auscultating heart sounds reveals a narrowly split second heart sound from pulmonary hypertension c) ECG shows an enlarged p wave in precordial leads and signs of LVH d) Chest Xray (AP) lateral shows hyperinflation and large retrosternal air space

ANSWER: A (Consensus A) Reference: Barash Pg. 884, Miller Ch. 90 Pg. 2660 ANSWER: A - Titanium Clips = FALSE: Miller: "Increasingly, vascular clips, staples, orthopedic implants, heart valves, and other prostheses are nonferromagnetic and scanning of patients with these implants is possible." Titanium is not a ferromagnetic material, and may be safely used in MRI machines. RE: B - Shrapnel = TRUE: Miller: "Any implanted devices must be assessed for MRI compatibility. Patients with pacemakers, implantable cardioverter-defibrillators (ICDs), cochlear implants, pumps, nerve stimulators, or other metal objects such as aneurysm clips, metal fragments, or bullets, should not be scanned. RE: C - Large Tattoo = TRUE: Barash: "Thermal injury may also occur in skin with large tattoos especially if these contain ferromagnetic inks." Red dye is particularly bad for this. RE: D - Pacemaker = TRUE: See Miller quote above.

95. ALL EXCEPT one of the following foreign bodies will create complications when going for an MRI. Indicate the exception? a) Titanium Clips b) Shrapnel c) Large Tattoo d) Pacemaker

ANSWER: C (Consensus C) References: Barash Pg. 1453, Lange Pg. 791 ANSWER: C - Bradycardia = FALSE: "Transient systemic metabolic acidosis and increased arterial carbon dioxide levels have been demonstrated after tourniquet deflation and do not cause deleterious effects in healthy patients. Measurable changes include a 10% to 15% increase in heart rate (C = FALSE), a 5% to 10% increase in serum potassium (B = TRUE), and a rise of 1 to 8 mm Hg in carbon dioxide tension in blood (D = TRUE). Prolonged inflation or the simultaneous release of two tourniquets is not recommended. It may produce clinically significant acidosis, particularly in patients with an underlying acidosis from other causes. Tourniquet release has also been associated with cerebral embolic phenomena." RE: Hypothermia = TRUE: While not explicitly mentioned by Barash, mechanistically can explain this, and Barash's quote directly contradicts the bradycardia claim by stating that tachycardia is actually seen. Lange (though not a Royal College Textbook) answers the question completely: "Cuff deflation invariably and immediately relieves tourniquet pain and associated hypertension. In fact, cuff deflation may be accompanied by a precipitous decrease in central venous and arterial blood pressure. Heart rate usually increases (C=FALSE) and core temperature decreases (A=TRUE). Washout of accumulated metabolic wastes in the ischemic extremity increases partial pressure of carbon dioxide in arterial blood (Paco2) (D=TRUE), end-tidal carbon dioxide (Etco2), and serum lactate and potassium levels (B=TRUE)."

96. Release of leg tourniquet is associated with all except: a) hypothermia b) hyperkalemia c) bradycardia d) Increased paCo2

ANSWER: D (Consensus D) Reference: Kaplan Ch. 12 Pg. 373-374 ANSWER: D - Coronary Blood Flow = FALSE: You cannot visualize coronary blood flow with TEE, though you can imply the presence of a lesion/ischemia in a given coronary vessel's perfusion territory based on the RWMAs seen. Kaplan: "By understanding coronary anatomy, the echocardiographer can make assumptions regarding localization of a potential coronary artery lesion based on the region of abnormal wall motion." RE: A - Diastolic ventricular function = TRUE: Diastolic dysfunction is one of the earliest markers of ischemia. Kaplan: "Abnormalities in diastolic function usually precede abnormal changes in systolic function. Normal function is critical for LV filling and is dependent on ventricular relaxation, compliance, and atrial contraction. Diastolic ventricular function can be assessed by monitoring the rate of filling associated with changes in the chamber dimensions (see earlier). Regional systolic function can be estimated by echocardiographic determination of wall thickening and wall motion during systole in both LAX and SAX views of the ventricle. The SAX view of the left ventricle at the papillary muscle level displays myocardium perfused by the three main coronary arteries and is, therefore, very useful. However, because the SAX view does not image the ventricular apex, and this is a common location of ischemia, the LAX and longitudinal ventricular views are also clinically important." RE: B - Systolic Ventricular Wall thickening = TRUE: Kaplan: "Although wall thickening is probably a more specific marker of ischemia than wall motion, its measurement requires visualization of the epicardium, which is not always possible." RE: C - Systolic ventricular wall motion = TRUE: Kaplan: "...by observing the movement of the endocardium toward the center of the cavity during systole, systolic wall motion can almost always be assessed. As the myocardial oxygen supply/demand balance worsens, graded systolic wall motion abnormalities progress from mild hypokinesia to severe hypokinesia, akinesia, and finally, dyskinesia."

97. TEE findings that can aid in diagnosis of myocardial ischemia, all except: a) diastolic ventricular function b) systolic ventricular wall thickening c) systolic ventricular wall motion d) coronary blood flow

ANSWER: D (Consensus D) References: Miller Table 59-6 (Pg. 1780), Miller Ch. 59 Pg. 1782-1784, Miller Ch. 61 Pg. 1863 Barash Pg. 1524, Barash Table 12-7 Pg. 299 ANSWER: D - Medium sized molecule with renal clearance = FALSE?: This is a nitpicky and terribly clinically irrelevant question: Based on the somewhat vague labeling in Miller, Voluven is listed as a 6% HES (130/0.4), which, based on a much more explicit quote from Barash, I can interpret this to mean that the starch has an average molecular weight of 130kDa, and has a Molar Substitution of 0.4. My interpretation of the information presented in Miller would put Voluven into the medium sized tetrastarch category. Based on quotes below, I don't think Voluven would fit into the low molecular weight category, which would be the only one renally cleared. Medium sized starches are excreted in the bile and feces. This is the only answer option with ambiguity, and options A, B, and C are all explicitly TRUE. There are frustratingly multiple definitions for High/Medium/Low molecular weight starches that Miller provides in the span of about 2 pages. First he lists just a single number to define each category: High MW = 450-480kDa; Medium MW = 200kDa; Low MW = 70kDa. He later discusses low molecular weight starches as being <50-60kDa. And finally, while discussing renal dysfunction, refers to "newer solutions with low MW (130 kDa/MS 0.4)". Concerningly, the 130kDa/MS 0.4 designation is exactly that of Voluven, so it is really unclear if Voluven does in fact fall under the low molecular weight or medium MW category. Miller defining the Molar Substitution ratio: "An alternative measure of substitution is the molar substitution (MS) ratio, calculated as the total number of hydroxyethyl groups present divided by the quantity of glucose molecules. MS is used to define starches as hetastarches (MS 0.7), hexastarches (MS 0.6), pentastarches (MS 0.5), or tetrastarches (MS 0.4)." Miller: "...colloid molecules may be lost from circulation in several ways— by filtration across capillaries whose barrier function is impaired by glycocalyx shedding, endothelial cell pore formation in inflammation or other stressors, or both; by renal filtration of smaller colloid molecules; or by removal from the circulation by metabolism." "Ongoing renal excretion accounts for the elimination of smaller HES molecules, with medium-sized molecules being excreted in the bile and feces. A proportion of larger molecules, particularly those resistant to hydrolysis, is taken up by the mononuclear phagocyte (reticuloendothelial) system, where they may persist for several weeks or more." (Voluven Customer Letter in Canadian Blood Services Website) The pharmacokinetic profile of HES is complex and largely dependent on its molar substitution as well as its molecular weight. When administered intravenously, molecules smaller than the renal threshold (60,000-70,000 Da) are readily and rapidly excreted in the urine, while molecules with higher molecular weights are metabolized by plasma amylase prior to excretion via the renal route. The mean in vivo molecular weight of VOLUVEN in plasma is 70,000-80,000 Da immediately following infusion and remains above the renal threshold throughout the treatment period. RE: A - Can have an anaphylactoid reaction = TRUE: While rare, they still do occur. Miller's quote is in reference to HES in general, not Voluven in particular: "ANAPHYLACTOID REACTIONS. The estimated incidence of severe anaphylactoid or anaphylactic reactions with HES products is less than with other colloids (<0.06%)." Barash Table 12-7 also lists colloid volume expanders including Hydroxyethyl starches as implicated in allergic reactions under anesthesia. RE: B - Contraindicated in sepsis = TRUE: Miller: "In 2013, the FDA Safety Information and Adverse Event Reporting Program published via their MedWatch program a 'Boxed Warning on Increased Mortality and Severe Renal Injury and Risk of Bleeding.' Specifically, they recommended that HES solutions not be administered to patients with sepsis who are in the ICU, those with preexisting renal function issues, and those undergoing cardiopulmonary bypass. Also if HES is being given, it should be stopped at the first sign of a coagulopathy and/or renal dysfunction." This quote from Miller seems to refer to the type of HES in Voluven specifically: "Although newer solutions with low MW (130 kDa/MS 0.4) were initially thought to be safer in this respect, recent large scale trials have shown a similar effect on the need for renal replacement therapy in severe sepsis, particularly when compared with balanced crystalloids." RE: C - Voluven made with NaCl 0.9% = TRUE: Miller Table 59-6 lists the composition of many IV crystalloid and colloid solutions; Voluven is a Waxy Maize Hydroxyethyl Starch 6% (130/0.4), with 154 mEq of both Sodium and Chloride. He further describes colloids as: "Colloid is defined as large molecules or ultramicroscopic particles of a homogeneous noncrystalline substance dispersed in a second substance, typically isotonic saline, or a balanced crystalloid."

98. Concerning hetastarches (eg. Voluven) all except: a) can have an anaphylactoid reaction b) Contraindicated in sepsis c) Voluven made with NaCl 0.9% d) medium sized molecule with renal clearance

ANSWER: A (Consensus A) References: Miller Ch. 38 Pg. 1119, Miller Ch. 39 Pg. 1204, Barash Pg. 1120, 1407 ANSWER: A - Hemodynamic instability = FALSE: Unless the patient is in heart failure, dialysis will likely lead to more hemodynamic instability due to a relatively hypovolemic state that typically results immediately post dialysis. This would be especially true in anuric patients who rely on dialysis for correction of both fluid status and electrolyte abnormalities. If they receive dialysis 3 times a week, they must be relatively hypovolemic immediately post dialysis, in order to allow them to survive to their next dialysis appointment in 48-72 hrs in an only slightly fluid overloaded state. Barash: "If patients receive chronic dialysis treatments, they should receive dialysis on the day before or the same day as surgery. Some patients will actually be hypovolemic as a result, which can contribute to hypotension with induction of general or regional anesthesia." Miller: "Preoperative renal replacement therapy (dialysis) schedules are coordinated, with scheduling of the surgical procedure ideally within 24 hours after dialysis. In elective surgical cases, dialysis should be performed within 24 hours of surgery but not immediately before, given the risks of acute volume depletion (A = FALSE) and electrolyte alterations (?D = FALSE?). Dialysis is associated with fluid shifts and electrolyte (sodium, potassium, magnesium, phosphate) imbalance, especially related to shifting of electrolytes between intracellular and extracellular compartments. Dialysis is performed to correct volume overload (B = TRUE), hyperkalemia, and acidosis." "Although preoperative dialysis may benefit patients who have hyperkalemia (D = TRUE), hypercalcemia (C = TRUE), acidosis, neuropathy, and fluid overload (B = TRUE), the resulting dysequilibrium between fluid and electrolytes can cause problems. Because hypovolemia induced by dialysis can lead to intraoperative hypotension (A = FALSE), we try to avoid weight and fluid reduction in patients undergoing preoperative dialysis." RE: B - Heart Failure/Hypervolemia = TRUE: Multiple quotes to suggest dialysis will improve heart failure/fluid overload. RE: C - Hypocalcemia/Calcium = TRUE?: Although the quote from Miller above suggesting dialysis improves hypercalcemia makes me want to assert that this option is meant to read hyper- not hypocalcemia, individuals with renal failure frequently do have coexisting low calcium levels: Barash Pg. 354: "In renal insufficiency, reduced phosphorus excretion results in hyperphosphatemia, which downregulates the 1α-hydroxylase responsible for the renal conversion of calcidiol to calcitriol. This, in combination with decreased production of calcitriol secondary to reduced renal mass, causes reduced intestinal absorption of calcium and hypocalcemia." Although I couldn't find a quote explicitly stating that dialysis would correct hypocalcemia, Miller does say that dialysis improves hypercalcemia and other electrolyte abnormalities. From my understanding, and a quick read of the literature, the dialysate contains an electrolyte solution with which the serum equilibrates, bringing hypo- or hyper- electrolyte abnormalities closer to their normal value (reflected in the chosen dialysate electrolyte composition). Typical dialysate calcium concentrations include a low (1.25 mmol/L) and high (1.75 mmol/L) calcium option. Depending on the anticoagulant used for dialysis, however, hypocalcemia may occur as a result: Barash Pg. 1407: "Hypocalcemia may be due to several mechanisms, including a decrease in PTH secretion or action, reduced vitamin D synthesis or action, resistance of bone to PTH or vitamin D effects, or calcium sequestration. Citrate used for regional anticoagulation with dialysis can also cause hypocalcemia and may also lead to hypomagnesemia from decreased PTH secretion." Despite the ambiguity of this option, I still feel it is meant to be a true statement, as option A is more clearly incorrect. RE: D - Sodium abnormalities/Electrolyte abnormalities = TRUE: Although the quotes in Miller suggest the immediate post-dialysis state is one of ongoing electrolyte flux between the extracellular and intracellular compartments, one of the main purposes of dialysis is to correct sodium/electrolyte abnormalities. In addition, the timing of "pre-op" dialysis in the question is not explicitly immediately pre-op, and could be meant to be within 24hrs of surgery (as is the recommendation).

99. 56 yo lady, dialysis dependent, pre-op dialysis will help with all except: a) hemodynamic instability b) heart failure c) hypocalcemia d) sodium abnormalities