ABA ABA Pharmacology & Drug Management 1 — Questions and Answers
Question 1: Which volatile anesthetic has the lowest blood-gas partition coefficient, resulting in the fastest induction and emergence?
- Isoflurane
- Sevoflurane
- Desflurane (Correct answer)
- Halothane
Correct answer: Desflurane
Desflurane has the lowest blood-gas partition coefficient (0.45) among commonly used volatile agents, allowing the fastest equilibration and emergence.
Question 2: A patient receives succinylcholine and develops masseter spasm followed by generalized rigidity and a rising temperature. The FIRST drug to administer is:
- Propofol
- Dantrolene (Correct answer)
- Calcium gluconate
- Sodium bicarbonate
Correct answer: Dantrolene
Dantrolene inhibits ryanodine receptor-mediated calcium release from the sarcoplasmic reticulum and is the definitive treatment for malignant hyperthermia.
Question 3: The MAC (minimum alveolar concentration) of a volatile anesthetic is DECREASED by which of the following?
- Hyperthermia
- Chronic alcohol use
- Opioid premedication (Correct answer)
- Hyperthyroidism
Correct answer: Opioid premedication
Opioid premedication reduces MAC by providing analgesia and CNS depression, decreasing the requirement for volatile agent.
Question 4: Which neuromuscular blocking agent is MOST appropriate for a patient with a known history of pseudocholinesterase deficiency?
- Succinylcholine
- Mivacurium
- Atracurium (Correct answer)
- Pancuronium
Correct answer: Atracurium
Atracurium undergoes Hofmann elimination and ester hydrolysis independent of pseudocholinesterase, making it safe in pseudocholinesterase deficiency.
Question 5: Which opioid is MOST likely to cause chest wall rigidity ('wooden chest syndrome') when given as a rapid IV bolus?
- Morphine
- Hydromorphone
- Fentanyl (Correct answer)
- Meperidine
Correct answer: Fentanyl
Fentanyl and other synthetic opioids given rapidly IV can cause truncal rigidity, likely via mu-receptor activation in the basal ganglia.
Question 6: The reversal agent sugammadex works by which mechanism?
- Inhibiting acetylcholinesterase at the neuromuscular junction
- Chelating aminosteroid neuromuscular blockers in plasma (Correct answer)
- Competing with rocuronium for nicotinic receptor binding
- Stimulating nicotinic acetylcholine receptors directly
Correct answer: Chelating aminosteroid neuromuscular blockers in plasma
Sugammadex is a modified gamma-cyclodextrin that encapsulates and chelates rocuronium and vecuronium in plasma, preventing receptor binding.
ABA ABA Pharmacology & Drug Management 1
Which volatile anesthetic has the lowest blood-gas partition coefficient, resulting in the fastest induction and emergence?