EDAIC Pharmacokinetics and Pharmacodynamics 2

Question 1

Which pharmacokinetic model best describes a drug that distributes rapidly to well-perfused tissues and more slowly to muscle and fat?

Accepted Answer

Three-compartment model

Answer

A three-compartment model describes a central compartment (blood/highly perfused organs) plus rapid-equilibrating (muscle) and slow-equilibrating (fat) peripheral compartments.

Question 2

The context-sensitive half-time of remifentanil is unique because it:

Accepted Answer

Remains constant at approximately 3-4 minutes regardless of infusion duration

Answer

Remifentanil is metabolized by nonspecific plasma and tissue esterases, so its context-sensitive half-time remains ~3-4 minutes regardless of infusion duration.

Question 3

Which parameter best describes the relationship between drug concentration and effect at steady state?

Accepted Answer

EC50

Answer

EC50 (half-maximal effective concentration) defines the plasma concentration at which 50% of the maximum drug effect is achieved, characterizing the concentration-effect relationship.

Question 4

A patient with severe hepatic cirrhosis receives midazolam. Which pharmacokinetic change is most expected?

Accepted Answer

Decreased clearance prolonging elimination half-life

Answer

Severe hepatic cirrhosis reduces hepatic metabolic capacity, decreasing midazolam clearance and markedly prolonging its elimination half-life.

Question 5

Enzyme induction by chronic phenytoin use would most significantly alter the pharmacokinetics of which co-administered drug?

Accepted Answer

Vecuronium

Answer

Vecuronium undergoes significant hepatic CYP3A4 metabolism; chronic phenytoin-induced CYP3A4 induction accelerates vecuronium clearance, reducing its duration of action.

EDAIC - European Diploma in Anesthesiology and Intensive Care Practice Test

EDAIC - European Diploma in Anesthesiology and Intensive Care Practice Test

EDAIC Pharmacokinetics and Pharmacodynamics 2