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AOBA Anesthesiology study materials
AOBA Anesthesiology study resources

AOBA Anesthesiology practice questions

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Question 1Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which nerve is blocked to provide surgical anesthesia of the skin overlying the anterior triangle of the neck during awake carotid endarterectomy?

  1. The transverse cervical nerve Correct answer.
  2. The greater auricular nerve
  3. The lesser occipital nerve
  4. The supraclavicular nerve

Explanation

The transverse cervical nerve (C2-C3) emerges at the midpoint of the posterior border of sternocleidomastoid and supplies sensation to the anterior neck. Superficial cervical plexus blockade for carotid surgery targets this nerve along with the greater auricular nerve.

Question 2Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

During one-lung ventilation, which of the following best explains the increase in shunt fraction compared with two-lung ventilation?

  1. The ventilated lung receives a greater share of pulmonary blood flow than during two-lung ventilation
  2. Mixed venous oxygen saturation rises because cardiac output falls
  3. Perfusion of the non-ventilated lung continues while hypoxic pulmonary vasoconstriction is only partial Correct answer.
  4. Functional residual capacity of the ventilated lung increases above closing capacity

Explanation

The non-dependent, non-ventilated lung continues to be perfused, creating true right-to-left shunt. Hypoxic pulmonary vasoconstriction reduces but does not abolish this perfusion, so shunt fraction rises.

Question 3Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A 70-kg adult is given 100 mg of a drug with a volume of distribution of 50 L. Assuming first-order elimination with a half-life of 4 hours, which plasma concentration is expected 4 hours after the dose (ignoring distribution phase)?

  1. 1 mg/L
  2. 4 mg/L
  3. 2 mg/L Correct answer.
  4. 0.5 mg/L

Explanation

Initial concentration equals dose divided by volume of distribution: 100 mg / 50 L = 2 mg/L. After one half-life the concentration falls by half, to 1 mg/L.

Question 4Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which structure passes through the foramen ovale of the sphenoid bone?

  1. The middle meningeal artery
  2. The mandibular division of the trigeminal nerve Correct answer.
  3. The internal carotid artery
  4. The maxillary division of the trigeminal nerve

Explanation

The foramen ovale transmits the mandibular division of the trigeminal nerve (V3), along with the lesser petrosal nerve and accessory meningeal artery. It is a landmark for percutaneous trigeminal ganglion procedures.

Question 5Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which best describes the mechanism by which succinylcholine produces neuromuscular blockade?

  1. Blockade of presynaptic voltage-gated calcium channels
  2. Inhibition of acetylcholinesterase at the neuromuscular junction
  3. Competitive antagonism at the nicotinic acetylcholine receptor
  4. Persistent depolarization of the motor end plate with desensitization Correct answer.

Explanation

Succinylcholine is a depolarizing blocker: it binds nicotinic receptors and maintains depolarization, so the end plate cannot repolarize and a phase I block results. Prolonged exposure can produce desensitization (phase II block).

Question 6Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A patient with severe aortic stenosis is anesthetized. Which hemodynamic change is least well tolerated because it can critically reduce coronary perfusion?

  1. A fall in systemic vascular resistance Correct answer.
  2. A rise in systemic vascular resistance
  3. A modest rise in preload
  4. A rise in heart rate to 110 beats per minute

Explanation

In aortic stenosis, fixed outflow obstruction means stroke volume cannot increase to compensate for vasodilation, so a fall in systemic vascular resistance causes hypotension and reduced coronary perfusion pressure. Maintaining afterload and sinus rhythm is essential.

Question 7Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which local anesthetic property determines the maximum rate at which the drug diffuses across the nerve membrane to reach its binding site?

  1. Lipid solubility Correct answer.
  2. pKa relative to tissue pH
  3. Molecular weight
  4. Protein binding

Explanation

Lipid solubility governs how readily the drug penetrates the lipid bilayer of the nerve membrane and thus potency and speed of penetration. pKa determines the fraction of uncharged base available, but lipid solubility drives membrane traversal.

Question 8Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Administration of a drug that inhibits cytochrome P450 3A4 would be expected to have which effect on a concurrently given drug that is a high-extraction, CYP3A4 substrate given orally?

  1. No change in oral bioavailability
  2. A large increase in oral bioavailability Correct answer.
  3. A small increase in oral bioavailability
  4. A decrease in oral bioavailability

Explanation

For a high-extraction drug, extensive first-pass hepatic metabolism limits oral bioavailability. Inhibiting the metabolizing enzyme reduces first-pass clearance and can markedly increase systemic exposure after oral dosing.

Question 9Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following is the primary determinant of the rate of alveolar uptake of an inhaled anesthetic?

  1. Blood:gas partition coefficient Correct answer.
  2. Molecular weight of the agent
  3. Oil:gas partition coefficient
  4. Minimum alveolar concentration

Explanation

The blood:gas partition coefficient determines solubility in blood; a low coefficient means less agent must be dissolved before alveolar partial pressure rises, so induction is faster. It is the principal determinant of alveolar uptake rate.

Question 10Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which receptor type is responsible for the rapid excitatory synaptic transmission at the neuromuscular junction?

  1. Metabotropic glutamate receptor
  2. G-protein coupled muscarinic receptor
  3. Ligand-gated nicotinic acetylcholine receptor Correct answer.
  4. Voltage-gated sodium channel

Explanation

The motor end plate contains nicotinic acetylcholine receptors that are ligand-gated cation channels. Acetylcholine binding opens the channel, producing a fast end-plate potential that triggers muscle contraction.

Question 11Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A patient with chronic obstructive pulmonary disease has an elevated functional residual capacity. Which change in the oxygen-hemoglobin dissociation curve is expected from chronic hypercapnia?

  1. No shift, because pH is compensated
  2. A left shift caused by increased 2,3-DPG
  3. A right shift, decreasing hemoglobin oxygen affinity Correct answer.
  4. A left shift, increasing hemoglobin oxygen affinity

Explanation

Chronic hypercapnia produces respiratory acidosis, and hydrogen ions stabilize the deoxygenated hemoglobin conformation, shifting the curve right (Bohr effect). This lowers affinity and favors oxygen unloading at the tissues.

Question 12Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which coronary artery most commonly supplies the atrioventricular node in the majority of individuals?

  1. The left anterior descending artery
  2. The left circumflex artery
  3. The right coronary artery Correct answer.
  4. The left main coronary artery

Explanation

In most people the right coronary artery is dominant and gives rise to the atrioventricular nodal branch. This is relevant because right coronary ischemia can cause heart block.

Question 13Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following best characterizes the effect of volatile anesthetics on the hypoxic pulmonary vasoconstriction response at clinically used concentrations?

  1. Marked potentiation of the response
  2. Complete abolition at 0.5 MAC
  3. No effect at any concentration
  4. Dose-dependent inhibition that is modest at typical concentrations Correct answer.

Explanation

Volatile anesthetics inhibit hypoxic pulmonary vasoconstriction in a dose-dependent manner, but the effect is modest at usual clinical concentrations. This matters during one-lung ventilation, where inhibition can worsen shunt.

Question 14Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following statements about the anatomy of the adult airway is correct?

  1. The carina lies at the level of the fourth thoracic vertebra in adults
  2. The right main bronchus is wider and more vertical than the left Correct answer.
  3. The vocal cords are innervated by the glossopharyngeal nerve
  4. The left main bronchus is wider and more vertical than the right

Explanation

The right main bronchus is wider, shorter, and more vertical, which is why aspirated material and misplaced tubes tend to enter the right lung. This anatomy explains the frequency of right endobronchial intubation.

Question 15Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A drug is a weak base with a pKa of 8.4. At a plasma pH of 7.4, which statement about its ionization is correct?

  1. It is equally ionized and unionized
  2. It is trapped in the urine regardless of urine pH
  3. It is mostly ionized, so little crosses lipid membranes Correct answer.
  4. It is mostly unionized, so it diffuses readily across membranes

Explanation

For a weak base, when pH is below the pKa, the protonated (ionized) form predominates. At pH 7.4 versus pKa 8.4, roughly 90% is ionized, which limits membrane diffusion.

Question 16Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following best explains why epinephrine is added to a local anesthetic solution for infiltration?

  1. It increases the pH of the solution
  2. It directly blocks sodium channels
  3. It causes vasoconstriction, slowing systemic absorption Correct answer.
  4. It increases the pKa of the local anesthetic

Explanation

Epinephrine produces local vasoconstriction, which reduces vascular uptake of the local anesthetic, prolonging block and limiting systemic toxicity. It does not change the drug's channel blocking action.

Question 17Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following is the principal mechanism by which volatile anesthetics depress myocardial contractility?

  1. Direct activation of beta-adrenergic receptors
  2. Enhanced sensitivity of myofilaments to calcium
  3. Inhibition of L-type calcium channels, reducing calcium entry Correct answer.
  4. Increased sarcoplasmic reticulum calcium release

Explanation

Volatile agents reduce calcium entry through L-type calcium channels in the sarcolemma and reduce calcium release from the sarcoplasmic reticulum, decreasing intracellular calcium available for contraction. The net effect is dose-dependent negative inotropy.

Question 18Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which cerebral physiologic change is produced by hyperventilation to a PaCO2 of 25 mmHg in a patient with normal intracranial compliance?

  1. No change in cerebral blood flow
  2. Increased cerebral blood volume
  3. Cerebral vasoconstriction with decreased cerebral blood flow Correct answer.
  4. Cerebral vasodilation with increased cerebral blood flow

Explanation

Cerebral blood flow changes approximately 2-4% per mmHg change in PaCO2 within the physiologic range. Hypocapnia causes cerebral vasoconstriction and reduces cerebral blood flow and volume.

Question 19Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which pharmacokinetic parameter is calculated as clearance divided by volume of distribution?

  1. Bioavailability
  2. Elimination half-life
  3. Absorption rate constant
  4. Elimination rate constant Correct answer.

Explanation

The elimination rate constant k equals clearance divided by volume of distribution. Half-life is related to k by the natural logarithm of 2 divided by k.

Question 20Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A patient receives a nondepolarizing neuromuscular blocker and develops prolonged paralysis. Which condition most likely explains this?

  1. Hypercalcemia
  2. Hypothermia Correct answer.
  3. Metabolic alkalosis
  4. Hyperkalemia

Explanation

Hypothermia reduces hepatic and renal clearance of many neuromuscular blockers and impairs neuromuscular transmission, prolonging blockade. Electrolyte disturbances such as hypokalemia and hypermagnesemia also potentiate blockade.

Question 21Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following best describes the Starling forces that govern fluid movement across the capillary membrane?

  1. Interstitial hydrostatic pressure favors filtration out of the capillary
  2. Plasma oncotic pressure favors reabsorption into the capillary Correct answer.
  3. Capillary hydrostatic pressure favors reabsorption into the capillary
  4. Interstitial oncotic pressure favors reabsorption into the capillary

Explanation

Plasma colloid oncotic pressure, generated mainly by albumin, pulls fluid back into the capillary and opposes filtration. Net filtration is determined by hydrostatic and oncotic gradients across the capillary wall.

Question 22Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following statements about the physiology of the baroreceptor reflex is correct?

  1. Baroreceptor firing increases sympathetic outflow
  2. Baroreceptors increase their firing rate when arterial pressure rises Correct answer.
  3. Baroreceptors are primarily sensitive to blood oxygen content
  4. Baroreceptors are located only in the aortic arch

Explanation

Arterial baroreceptors in the carotid sinus and aortic arch are stretch sensitive and increase firing as pressure rises. Increased firing inhibits sympathetic outflow and increases vagal tone, lowering heart rate and pressure.

Question 23Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following best explains why a patient with a full stomach is at increased risk of aspiration during induction of anesthesia?

  1. Increased laryngeal reflex sensitivity during induction
  2. Anesthetic agents increase lower esophageal sphincter tone
  3. Loss of protective airway reflexes and increased intragastric pressure Correct answer.
  4. Reduced gastric volume from delayed emptying

Explanation

Induction of anesthesia abolishes protective laryngeal reflexes while positive-pressure ventilation and cricoid pressure can raise intragastric pressure, promoting regurgitation. The combination increases aspiration risk.

Question 24Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following is the most likely explanation for the reduced MAC requirement observed in a patient with severe hypothermia?

  1. Enhanced volatile agent uptake into adipose tissue
  2. Increased cerebral metabolic rate
  3. Increased release of excitatory neurotransmitters
  4. Reduced cerebral metabolic rate and neuronal excitability Correct answer.

Explanation

MAC correlates with cerebral metabolic rate; hypothermia reduces cerebral metabolism and neuronal excitability, lowering the concentration needed to produce immobility. This parallels the reduction in MAC by other central depressants.

Question 25Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following best characterizes the effect of a pure alpha-1 adrenergic agonist on the vasculature?

  1. Bronchodilation via beta-2 stimulation
  2. Negative inotropy via beta-1 blockade
  3. Vasodilation via endothelial nitric oxide release
  4. Vasoconstriction via smooth muscle contraction Correct answer.

Explanation

Alpha-1 receptors on vascular smooth muscle couple to Gq and increase intracellular calcium, producing contraction and vasoconstriction. This raises systemic vascular resistance and blood pressure.

Question 26Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which nerve is most commonly blocked to provide anesthesia for the anterior two-thirds of the tongue?

  1. Inferior alveolar nerve
  2. Glossopharyngeal nerve
  3. Lingual nerve Correct answer.
  4. Hypoglossal nerve

Explanation

The lingual nerve, a branch of the mandibular division of the trigeminal nerve, provides general sensory innervation to the anterior two-thirds of the tongue. The inferior alveolar nerve supplies the lower teeth and chin, the glossopharyngeal nerve supplies the posterior third of the tongue, and the hypoglossal nerve is motor to the tongue.

Question 27Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A patient with a history of asthma is scheduled for surgery. Which volatile anesthetic is least likely to cause bronchoconstriction?

  1. Desflurane
  2. Isoflurane
  3. Nitrous oxide
  4. Sevoflurane Correct answer.

Explanation

Sevoflurane is known for its bronchodilatory properties and is often used in patients with reactive airway disease. Desflurane and isoflurane can cause airway irritation and bronchoconstriction, and nitrous oxide lacks significant bronchodilatory effects.

Question 28Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A 70-kg patient is receiving a continuous infusion of a drug with a clearance of 4 L/min and a volume of distribution of 100 L. What is the elimination half-life of this drug?

  1. 25 minutes
  2. 34.7 minutes
  3. 17.3 minutes Correct answer.
  4. 50 minutes

Explanation

Half-life is calculated as (0.693 × volume of distribution) / clearance. For this drug, (0.693 × 100 L) / 4 L/min = 17.325 minutes, which rounds to 17.3 minutes.

Question 29Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

Which of the following best explains why a patient with severe liver disease may have an increased sensitivity to the effects of midazolam?

  1. Decreased volume of distribution of midazolam
  2. Decreased hepatic metabolism of midazolam Correct answer.
  3. Increased renal excretion of midazolam
  4. Increased plasma protein binding of midazolam

Explanation

Midazolam undergoes extensive hepatic metabolism via cytochrome P450 enzymes. In severe liver disease, hepatic clearance is reduced, leading to prolonged elimination half-life and increased sensitivity. Plasma protein binding may be decreased (not increased), and renal excretion is not the primary route.

Question 30Basic Sciences Applied to Anesthesiology (anatomy, physiology, pharmacology)

A 65-year-old man with chronic obstructive pulmonary disease and a history of smoking presents for elective surgery. His preoperative arterial blood gas on room air shows: pH 7.34, PaCO2 55 mmHg, PaO2 60 mmHg, and HCO3- 29 mEq/L. Which of the following best describes the acid-base disturbance?

  1. Metabolic alkalosis with respiratory compensation
  2. Acute respiratory acidosis without metabolic compensation
  3. Chronic respiratory acidosis with metabolic compensation Correct answer.
  4. Chronic respiratory alkalosis with metabolic compensation

Explanation

The elevated PaCO2 indicates respiratory acidosis. The pH is only mildly decreased, and the bicarbonate is elevated, indicating renal compensation. In acute respiratory acidosis, bicarbonate rises by only about 1 mEq/L for every 10 mmHg increase in PaCO2; here, the increase in bicarbonate is greater, consistent with chronic compensation.

Question 31Preanesthetic Evaluation and Perioperative Assessment

A patient scheduled for elective surgery reports a history of anaphylaxis after eating shellfish and has never been exposed to anesthetic agents. Which preoperative preparation is most appropriate?

  1. Document the allergy and avoid latex and other cross-reacting exposures while preparing for possible anaphylaxis Correct answer.
  2. Premedicate with an antihistamine and proceed regardless of airway findings
  3. Cancel surgery permanently because of the allergy history
  4. Proceed without modification because food allergy does not affect anesthesia

Explanation

A documented anaphylactic allergy warrants clear charting and avoidance of known and cross-reacting triggers, with readiness to treat anaphylaxis. Shellfish allergy is not a contraindication to anesthesia, but the team must be prepared. Routine antihistamine premedication does not substitute for trigger avoidance.

Question 32Preanesthetic Evaluation and Perioperative Assessment

Which preoperative laboratory test is most clearly indicated before major surgery in a patient with known severe chronic kidney disease?

  1. Serum potassium and creatinine Correct answer.
  2. Liver function tests
  3. Serum amylase
  4. Coagulation profile

Explanation

In severe chronic kidney disease, electrolyte and renal function assessment guides fluid, potassium, and drug dosing decisions. Potassium and creatinine directly reflect the main perioperative risks. Other tests are obtained only when clinically indicated.

Question 33Preanesthetic Evaluation and Perioperative Assessment

An otherwise healthy 30-year-old presents for minor ambulatory surgery. Which set of routine preoperative tests is recommended?

  1. Pulmonary function tests and arterial blood gas
  2. No routine testing unless indicated by history or examination Correct answer.
  3. Complete blood count, electrolytes, and coagulation studies
  4. Chest radiograph and electrocardiogram

Explanation

Routine preoperative testing in healthy young patients without clinical indications does not improve outcomes and can cause false positives. Testing should be driven by history, examination, and the planned procedure. Indiscriminate panels are discouraged.

Question 34Preanesthetic Evaluation and Perioperative Assessment

A patient with a documented latex allergy is scheduled for surgery. Which preoperative measure best reduces the risk of an intraoperative reaction?

  1. Delay surgery until allergy testing is repeated
  2. Schedule as the first case of the day in a latex-safe environment Correct answer.
  3. Administer a steroid the night before surgery only
  4. Use powdered gloves but avoid latex tubing

Explanation

Latex-allergic patients should be managed in a latex-safe environment, and scheduling first case reduces airborne latex particle exposure from prior cases. Steroids alone do not prevent reactions. Powdered latex gloves increase aerosolized allergen.

Question 35Preanesthetic Evaluation and Perioperative Assessment

Which finding on preoperative history most strongly predicts difficult mask ventilation during induction?

  1. History of hypertension
  2. Body mass index over 30 with a beard Correct answer.
  3. Prior tonsillectomy
  4. Age over 60 years

Explanation

Obesity, presence of a beard, and older age are recognized predictors of difficult mask ventilation. Among the options, obesity with a beard is the strongest combination. Hypertension and prior tonsillectomy are not established predictors.

Question 36Preanesthetic Evaluation and Perioperative Assessment

A patient reports a prior severe reaction to succinylcholine with prolonged paralysis. Which preoperative consideration is most important?

  1. Assess for pseudocholinesterase deficiency and plan alternative neuromuscular blockade Correct answer.
  2. Premedicate with a histamine blocker
  3. Check serum calcium
  4. Obtain an echocardiogram

Explanation

Prolonged paralysis after succinylcholine suggests butyrylcholinesterase (pseudocholinesterase) deficiency. The team should plan to avoid succinylcholine and consider alternative agents. Histamine blockade, echocardiography, and calcium testing do not address this risk.

Question 37Preanesthetic Evaluation and Perioperative Assessment

A patient with severe aortic stenosis is being evaluated before elective surgery. Which perioperative risk is of greatest concern?

  1. Delayed emergence from anesthesia
  2. Inability to maintain coronary perfusion during hypotension Correct answer.
  3. Hyperkalemia from induction agents
  4. Increased bleeding from valvular disease

Explanation

In severe aortic stenosis, fixed cardiac output makes the patient highly dependent on preload and systemic vascular resistance to maintain coronary perfusion. Hypotension can cause myocardial ischemia and collapse. Electrolyte and bleeding issues are not the central concern.

Question 38Preanesthetic Evaluation and Perioperative Assessment

Which preoperative assessment best estimates functional capacity in a patient being evaluated for major surgery?

  1. Resting heart rate
  2. Serum albumin level
  3. Body temperature
  4. Ability to climb two flights of stairs without symptoms Correct answer.

Explanation

Functional capacity is best assessed by the patient's ability to perform activities of daily living and exercise. Inability to climb two flights of stairs suggests poor functional capacity and higher perioperative risk. Laboratory values and vital signs do not directly measure functional capacity.

Question 39Preanesthetic Evaluation and Perioperative Assessment

A patient with obstructive sleep apnea is scheduled for outpatient surgery. Which preoperative factor most increases the risk of perioperative respiratory complications?

  1. Mild intermittent asthma
  2. Concurrent use of opioids for pain control Correct answer.
  3. History of seasonal allergies
  4. Use of a home continuous positive airway pressure device

Explanation

Opioids depress ventilatory drive and worsen upper airway obstruction in patients with obstructive sleep apnea. This interaction substantially increases perioperative respiratory risk. Treated sleep apnea, allergies, and mild asthma are less prominent contributors.

Question 40Preanesthetic Evaluation and Perioperative Assessment

Which preoperative medication history is most important to clarify in a patient taking warfarin for atrial fibrillation before elective surgery?

  1. Timing of the last dose and current international normalized ratio Correct answer.
  2. Dietary intake of green vegetables
  3. History of childhood immunizations
  4. Use of multivitamin supplements

Explanation

For patients on warfarin, the current INR and timing of the last dose guide decisions about holding, bridging, and timing of surgery. Dietary and supplement history are secondary. Immunization history is irrelevant to anticoagulation management.

Question 41Preanesthetic Evaluation and Perioperative Assessment

A patient with a history of malignant hyperthermia susceptibility requires surgery. Which preoperative action is most appropriate?

  1. Premedicate with atropine
  2. Proceed with standard volatile anesthetics
  3. Avoid triggering agents and prepare dantrolene Correct answer.
  4. Use succinylcholine with close monitoring

Explanation

Malignant hyperthermia-susceptible patients must avoid triggering agents such as volatile anesthetics and succinylcholine, and dantrolene must be available. Atropine and standard volatile agents do not mitigate the risk. Proceeding with triggers is unsafe.

Question 42Preanesthetic Evaluation and Perioperative Assessment

A 70-year-old with a recent myocardial infarction is scheduled for elective surgery. Which timing consideration is most important?

  1. Reduce anesthetic depth to avoid cardiac stress
  2. Cancel all future surgery
  3. Proceed immediately because anesthesia is safe at any time
  4. Delay elective surgery until the risk of perioperative cardiac events has declined Correct answer.

Explanation

Recent myocardial infarction substantially increases perioperative cardiac risk, and elective surgery should be delayed until that risk declines, guided by cardiology input. Immediate surgery or permanent cancellation is inappropriate. Reducing anesthetic depth does not address the underlying risk.

Question 43Preanesthetic Evaluation and Perioperative Assessment

Which preoperative finding is most consistent with a difficult airway on physical examination?

  1. Mallampati class I
  2. Reduced neck extension Correct answer.
  3. Interincisor gap greater than 5 cm
  4. Thyromental distance greater than 6.5 cm

Explanation

Reduced neck extension limits positioning for laryngoscopy and is associated with difficult airway management. Mallampati class I, adequate thyromental distance, and adequate mouth opening suggest an easier airway. Multiple abnormal findings increase concern.

Question 44Preanesthetic Evaluation and Perioperative Assessment

A patient with cirrhosis is scheduled for abdominal surgery. Which preoperative finding most increases perioperative risk?

  1. History of childhood jaundice
  2. Mild elevation of transaminases
  3. Isolated hyperbilirubinemia without other abnormalities
  4. Coagulopathy with thrombocytopenia and ascites Correct answer.

Explanation

In cirrhosis, the combination of coagulopathy, thrombocytopenia, and ascites reflects advanced liver disease and portal hypertension, which substantially increases perioperative risk. Isolated mild enzyme elevations are less predictive.

Question 45Preanesthetic Evaluation and Perioperative Assessment

A patient with poorly controlled diabetes is scheduled for elective surgery. Which preoperative strategy best reduces perioperative risk?

  1. Optimize glycemic control and plan perioperative glucose monitoring Correct answer.
  2. Withhold all insulin on the morning of surgery regardless of regimen
  3. Administer a large dose of long-acting insulin the night before
  4. Proceed without glucose monitoring during surgery

Explanation

Poorly controlled diabetes increases infection, wound, and metabolic complications; preoperative optimization and intraoperative glucose monitoring improve outcomes. Withholding all insulin or giving excess long-acting insulin risks hyperglycemia or hypoglycemia. Monitoring is essential.

Question 46Preanesthetic Evaluation and Perioperative Assessment

Which preoperative factor most increases the risk of pulmonary aspiration during induction of anesthesia?

  1. History of gastroesophageal reflux with full stomach Correct answer.
  2. History of migraine
  3. Mild renal impairment
  4. Use of a beta blocker

Explanation

Gastroesophageal reflux combined with a full stomach increases the risk of aspiration during induction. Beta blockers, mild renal impairment, and migraine do not directly increase aspiration risk. Aspiration risk guides airway and fasting decisions.

Question 47Preanesthetic Evaluation and Perioperative Assessment

A patient with a pacemaker is scheduled for surgery using electrocautery. Which preoperative information is most important to obtain?

  1. Family history of diabetes
  2. Serum magnesium level
  3. History of childhood asthma
  4. Device type, pacing dependency, and magnet response Correct answer.

Explanation

Knowing the device type, whether the patient is pacing-dependent, and how the device responds to a magnet guides perioperative management and cautery precautions. Electrolytes, asthma, and family history are not the central issues.

Question 48Preanesthetic Evaluation and Perioperative Assessment

Which preoperative assessment is most useful before surgery in a patient with known severe chronic obstructive pulmonary disease?

  1. Obtain routine serum electrolytes only
  2. Measure serum amylase
  3. Perform a pregnancy test
  4. Assess baseline dyspnea, oxygen requirement, and recent exacerbations Correct answer.

Explanation

In severe COPD, baseline respiratory status, oxygen needs, and recent exacerbations predict perioperative pulmonary complications and guide optimization. Routine electrolytes, amylase, and pregnancy testing do not assess respiratory risk.

Question 49Preanesthetic Evaluation and Perioperative Assessment

A patient reports a family history of death during anesthesia in a first-degree relative. Which preoperative action is most appropriate?

  1. Proceed with succinylcholine because the patient is asymptomatic
  2. Obtain further details and consider evaluation for malignant hyperthermia susceptibility Correct answer.
  3. Ignore the history if the patient has had prior uneventful anesthesia
  4. Cancel surgery permanently

Explanation

A family history of anesthetic-related death may suggest malignant hyperthermia susceptibility or other inherited conditions. Further history and possible referral for evaluation are warranted. Prior uneventful anesthesia does not exclude susceptibility, and succinylcholine is a trigger.

Question 50Preanesthetic Evaluation and Perioperative Assessment

A patient with a history of severe postoperative nausea and vomiting after prior surgery is scheduled for an elective procedure. Which preoperative plan best addresses this risk?

  1. Use a multimodal antiemetic prophylaxis strategy based on risk factors Correct answer.
  2. Withhold all opioids postoperatively regardless of pain
  3. Delay surgery until nausea resolves
  4. Avoid all antiemetics until symptoms occur

Explanation

A history of severe postoperative nausea and vomiting is a strong predictor of recurrence, and risk-based multimodal prophylaxis is recommended. Waiting for symptoms or withholding all opioids is not appropriate. Delaying surgery is unnecessary.