MORGAN AND MIKHAILS CLINICAL ANESTHESIOLOGY 340+ QUESTIONS AND
ANSWERS COMPLETE REVIEW COMPREHENSIVE CLINICAL ANESTHESIOLOGY
STUDY PACK
Q1: What are the four components of a complete anesthetic?
Answer: Unconsciousness (hypnosis), analgesia, muscle relaxation, and
attenuation of autonomic reflexes.
Q2: What is the ASA physical status classification for a patient with severe
systemic disease that is a constant threat to life?
Answer: ASA Class IV.
Q3: What ASA class is assigned to a healthy patient with no systemic
disease?
Answer: ASA Class I.
Q4: What does the 'E' suffix in ASA classification denote?
Answer: Emergency surgery.
Q5: What is MAC (Minimum Alveolar Concentration)?
Answer: The alveolar concentration of an inhaled anesthetic that prevents
movement in 50% of patients in response to a surgical skin incision.
Q6: What is the typical duration of the preanesthetic evaluation?
Answer: It should be conducted prior to the day of surgery when possible, but
must occur before anesthetic care is initiated.
Q7: What information is essential in a preanesthetic evaluation?
Answer: Medical history, medications, allergies, prior anesthetic history,
airway exam, NPO status, and laboratory/diagnostic results.
2. Pharmacological Principles
,Q8: What is the volume of distribution (Vd)?
Answer: The apparent volume into which a drug distributes; calculated as
dose divided by plasma concentration (Vd = Dose/Cp). A large Vd indicates
extensive tissue distribution.
Q9: What is first-order kinetics?
Answer: A constant fraction (not amount) of drug is eliminated per unit time;
plasma concentration decreases exponentially.
Q10: What is zero-order kinetics?
Answer: A constant amount (not fraction) of drug is eliminated per unit time,
regardless of plasma concentration (e.g., ethanol, aspirin in overdose).
Q11: Define half-life (t½) of a drug.
Answer: The time required for the plasma concentration to decrease by 50%.
For first-order kinetics: t½ = 0.693 × Vd / Clearance.
Q12: What is the context-sensitive half-time?
Answer: The time for plasma concentration to decrease by 50% after
stopping a continuous infusion; depends on infusion duration. Important for
drugs like fentanyl and propofol.
Q13: What does protein binding of drugs affect?
Answer: Only unbound (free) drug is pharmacologically active. High protein
binding reduces drug availability and can be altered by hypoalbuminemia or
competition from other drugs.
Q14: What is the hepatic extraction ratio?
Answer: The fraction of drug removed from blood during a single pass
through the liver. High extraction (>0.7) means clearance depends mainly on
hepatic blood flow.
Q15: What is tachyphylaxis?
Answer: Rapid decrease in response to a drug after repeated doses; occurs
with ephedrine and nitroprusside.
Q16: What is the difference between potency and efficacy?
Answer: Potency refers to the dose required to produce an effect (EC50);
efficacy is the maximum effect a drug can produce regardless of dose.
Q17: What is an agonist vs. antagonist?
, Answer: An agonist binds to a receptor and produces a response; an
antagonist binds without producing a response and blocks agonists.
3. Inhalation Anesthetics
Q18: What factors determine the rate of rise of alveolar anesthetic
concentration (FA/FI)?
Answer: Alveolar ventilation, cardiac output, blood-gas solubility coefficient,
and the concentration/second gas effect.
Q19: What is the blood-gas partition coefficient?
Answer: The ratio of anesthetic concentration in blood to gas at equilibrium. A
higher coefficient means greater blood solubility and slower induction (e.g.,
halothane = 2.4; desflurane = 0.45).
Q20: Which inhalation anesthetic has the lowest blood-gas partition
coefficient?
Answer: Desflurane (0.45), allowing the fastest induction and emergence.
Q21: What is the MAC of isoflurane, sevoflurane, and desflurane in adults?
Answer: Isoflurane: 1.17%; Sevoflurane: 2.05%; Desflurane: 6.0%.
Q22: How does nitrous oxide affect MAC of volatile anesthetics?
Answer: Nitrous oxide has additive MAC effects; 70% N2O reduces the
requirement of volatile agents by approximately 60–70%.
Q23: What factors decrease MAC?
Answer: Increasing age, hypothermia, hypotension, opioids, alpha-2 agonists,
sedative-hypnotics, pregnancy, and acute alcohol intoxication.
Q24: What factors increase MAC?
Answer: Hyperthermia, chronic alcohol abuse, hypernatremia, and CNS
stimulants (cocaine, ephedrine).
Q25: What is the concentration effect?
Answer: Using a high inspired concentration of an anesthetic accelerates the
rise of alveolar concentration (FA/FI) beyond what would be predicted by
ventilation alone.
Q26: What is the second gas effect?
, Answer: The rapid uptake of a high-concentration gas (e.g., N2O)
concentrates a simultaneously administered gas (e.g., volatile agent),
accelerating its alveolar rise.
Q27: Which volatile anesthetic is most associated with hepatotoxicity?
Answer: Halothane, causing halothane hepatitis via immune-mediated
mechanisms from trifluoroacetyl metabolites.
Q28: What is diffusion hypoxia?
Answer: At the end of N2O anesthesia, rapid diffusion of N2O from blood into
alveoli dilutes alveolar O2, potentially causing hypoxia. Prevented by
administering 100% O2 for 5–10 minutes.
Q29: What is the mechanism of malignant hyperthermia (MH)?
Answer: Uncontrolled release of calcium from the sarcoplasmic reticulum in
susceptible individuals exposed to volatile anesthetics or succinylcholine,
causing hypermetabolism.
Q30: What is the treatment for malignant hyperthermia?
Answer: Stop the triggering agent, administer dantrolene (2.5 mg/kg IV,
repeat as needed), cooling measures, treat hyperkalemia and acidosis, and
supportive care.
Q31: How does sevoflurane differ from desflurane in airway irritation?
Answer: Sevoflurane has a pleasant odor and minimal airway irritation
(suitable for mask induction); desflurane is pungent and causes airway
irritation, making it unsuitable for mask induction.
Q32: What metabolite of sevoflurane is nephrotoxic in animals?
Answer: Compound A (fluoromethyl-2,2-difluoro-1-(trifluoromethyl)vinyl
ether), produced by reaction with soda lime. Clinically significant toxicity in
humans has not been demonstrated.
Q33: What cardiovascular effects do volatile anesthetics have in common?
Answer: Dose-dependent decrease in blood pressure (primarily via
decreased SVR or myocardial depression), and blunting of baroreceptor
reflexes.
Q344: Why does desflurane require a special vaporizer?
Answer: Desflurane boils at 22.8°C (near room temperature), so it cannot be
used in standard variable-bypass vaporizers. The Tec-6 Plus vaporizer is
electrically heated to 39°C and pressurized to deliver precise concentrations.
ANSWERS COMPLETE REVIEW COMPREHENSIVE CLINICAL ANESTHESIOLOGY
STUDY PACK
Q1: What are the four components of a complete anesthetic?
Answer: Unconsciousness (hypnosis), analgesia, muscle relaxation, and
attenuation of autonomic reflexes.
Q2: What is the ASA physical status classification for a patient with severe
systemic disease that is a constant threat to life?
Answer: ASA Class IV.
Q3: What ASA class is assigned to a healthy patient with no systemic
disease?
Answer: ASA Class I.
Q4: What does the 'E' suffix in ASA classification denote?
Answer: Emergency surgery.
Q5: What is MAC (Minimum Alveolar Concentration)?
Answer: The alveolar concentration of an inhaled anesthetic that prevents
movement in 50% of patients in response to a surgical skin incision.
Q6: What is the typical duration of the preanesthetic evaluation?
Answer: It should be conducted prior to the day of surgery when possible, but
must occur before anesthetic care is initiated.
Q7: What information is essential in a preanesthetic evaluation?
Answer: Medical history, medications, allergies, prior anesthetic history,
airway exam, NPO status, and laboratory/diagnostic results.
2. Pharmacological Principles
,Q8: What is the volume of distribution (Vd)?
Answer: The apparent volume into which a drug distributes; calculated as
dose divided by plasma concentration (Vd = Dose/Cp). A large Vd indicates
extensive tissue distribution.
Q9: What is first-order kinetics?
Answer: A constant fraction (not amount) of drug is eliminated per unit time;
plasma concentration decreases exponentially.
Q10: What is zero-order kinetics?
Answer: A constant amount (not fraction) of drug is eliminated per unit time,
regardless of plasma concentration (e.g., ethanol, aspirin in overdose).
Q11: Define half-life (t½) of a drug.
Answer: The time required for the plasma concentration to decrease by 50%.
For first-order kinetics: t½ = 0.693 × Vd / Clearance.
Q12: What is the context-sensitive half-time?
Answer: The time for plasma concentration to decrease by 50% after
stopping a continuous infusion; depends on infusion duration. Important for
drugs like fentanyl and propofol.
Q13: What does protein binding of drugs affect?
Answer: Only unbound (free) drug is pharmacologically active. High protein
binding reduces drug availability and can be altered by hypoalbuminemia or
competition from other drugs.
Q14: What is the hepatic extraction ratio?
Answer: The fraction of drug removed from blood during a single pass
through the liver. High extraction (>0.7) means clearance depends mainly on
hepatic blood flow.
Q15: What is tachyphylaxis?
Answer: Rapid decrease in response to a drug after repeated doses; occurs
with ephedrine and nitroprusside.
Q16: What is the difference between potency and efficacy?
Answer: Potency refers to the dose required to produce an effect (EC50);
efficacy is the maximum effect a drug can produce regardless of dose.
Q17: What is an agonist vs. antagonist?
, Answer: An agonist binds to a receptor and produces a response; an
antagonist binds without producing a response and blocks agonists.
3. Inhalation Anesthetics
Q18: What factors determine the rate of rise of alveolar anesthetic
concentration (FA/FI)?
Answer: Alveolar ventilation, cardiac output, blood-gas solubility coefficient,
and the concentration/second gas effect.
Q19: What is the blood-gas partition coefficient?
Answer: The ratio of anesthetic concentration in blood to gas at equilibrium. A
higher coefficient means greater blood solubility and slower induction (e.g.,
halothane = 2.4; desflurane = 0.45).
Q20: Which inhalation anesthetic has the lowest blood-gas partition
coefficient?
Answer: Desflurane (0.45), allowing the fastest induction and emergence.
Q21: What is the MAC of isoflurane, sevoflurane, and desflurane in adults?
Answer: Isoflurane: 1.17%; Sevoflurane: 2.05%; Desflurane: 6.0%.
Q22: How does nitrous oxide affect MAC of volatile anesthetics?
Answer: Nitrous oxide has additive MAC effects; 70% N2O reduces the
requirement of volatile agents by approximately 60–70%.
Q23: What factors decrease MAC?
Answer: Increasing age, hypothermia, hypotension, opioids, alpha-2 agonists,
sedative-hypnotics, pregnancy, and acute alcohol intoxication.
Q24: What factors increase MAC?
Answer: Hyperthermia, chronic alcohol abuse, hypernatremia, and CNS
stimulants (cocaine, ephedrine).
Q25: What is the concentration effect?
Answer: Using a high inspired concentration of an anesthetic accelerates the
rise of alveolar concentration (FA/FI) beyond what would be predicted by
ventilation alone.
Q26: What is the second gas effect?
, Answer: The rapid uptake of a high-concentration gas (e.g., N2O)
concentrates a simultaneously administered gas (e.g., volatile agent),
accelerating its alveolar rise.
Q27: Which volatile anesthetic is most associated with hepatotoxicity?
Answer: Halothane, causing halothane hepatitis via immune-mediated
mechanisms from trifluoroacetyl metabolites.
Q28: What is diffusion hypoxia?
Answer: At the end of N2O anesthesia, rapid diffusion of N2O from blood into
alveoli dilutes alveolar O2, potentially causing hypoxia. Prevented by
administering 100% O2 for 5–10 minutes.
Q29: What is the mechanism of malignant hyperthermia (MH)?
Answer: Uncontrolled release of calcium from the sarcoplasmic reticulum in
susceptible individuals exposed to volatile anesthetics or succinylcholine,
causing hypermetabolism.
Q30: What is the treatment for malignant hyperthermia?
Answer: Stop the triggering agent, administer dantrolene (2.5 mg/kg IV,
repeat as needed), cooling measures, treat hyperkalemia and acidosis, and
supportive care.
Q31: How does sevoflurane differ from desflurane in airway irritation?
Answer: Sevoflurane has a pleasant odor and minimal airway irritation
(suitable for mask induction); desflurane is pungent and causes airway
irritation, making it unsuitable for mask induction.
Q32: What metabolite of sevoflurane is nephrotoxic in animals?
Answer: Compound A (fluoromethyl-2,2-difluoro-1-(trifluoromethyl)vinyl
ether), produced by reaction with soda lime. Clinically significant toxicity in
humans has not been demonstrated.
Q33: What cardiovascular effects do volatile anesthetics have in common?
Answer: Dose-dependent decrease in blood pressure (primarily via
decreased SVR or myocardial depression), and blunting of baroreceptor
reflexes.
Q344: Why does desflurane require a special vaporizer?
Answer: Desflurane boils at 22.8°C (near room temperature), so it cannot be
used in standard variable-bypass vaporizers. The Tec-6 Plus vaporizer is
electrically heated to 39°C and pressurized to deliver precise concentrations.
