FANZCA Clinical Pharmacology and Anesthesia Flashcards
6 cards from real FANZCA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 FANZCA Clinical Pharmacology and Anesthesia flashcards as text
Which pharmacodynamic parameter describes the concentration of a drug required to produce 50% of its maximum effect?
Answer: EC50
The EC50 (effective concentration 50%) represents the drug concentration at which 50% of the maximum pharmacological effect is achieved, reflecting potency.
What is the primary mechanism by which ketamine produces dissociative anesthesia?
Answer: NMDA receptor antagonism
Ketamine primarily acts as an NMDA receptor antagonist, blocking glutamate-mediated excitation to produce its characteristic dissociative state, analgesia, and bronchodilation.
Which inhalational agent is contraindicated in patients with a known or suspected genetic predisposition to malignant hyperthermia?
Answer: All potent volatile halogenated agents
All potent volatile halogenated agents (halothane, isoflurane, sevoflurane, desflurane) are triggers for malignant hyperthermia and must be avoided in susceptible patients.
What is the clinical significance of the context-sensitive half-time in intravenous anesthetic pharmacokinetics?
Answer: It represents the half-life of a drug after infusion ceases, which increases with longer infusions for many drugs
Context-sensitive half-time is the time for plasma concentration to fall by 50% after stopping an infusion; for drugs like fentanyl, this lengthens considerably with prolonged infusions.
Which drug class used in anesthesia acts by inhibiting cyclooxygenase enzymes to provide multimodal analgesia as part of an opioid-sparing strategy?
Answer: NSAIDs
NSAIDs reduce prostaglandin synthesis by inhibiting COX-1 and COX-2 enzymes, providing anti-inflammatory analgesia that reduces opioid requirements perioperatively.
What is the pharmacological rationale for using dexmedetomidine as a sedative in the ICU or as an adjunct in anesthesia?
Answer: It selectively activates alpha-2 adrenoceptors to produce sedation, analgesia, and anxiolysis without significant respiratory depression
Dexmedetomidine's selective alpha-2 agonism in the locus coeruleus and spinal cord produces cooperative sedation and analgesia while preserving respiratory drive.