Pharmacology for Nurse Anesthetists Flashcards

Which drug is the treatment of choice for acute malignant hyperthermia crisis?

Answer: Dantrolene

Dantrolene inhibits ryanodine receptor-mediated calcium release from the sarcoplasmic reticulum, directly treating the hyperthermia and muscle rigidity of MH.

The opioid reversal agent naloxone works by which mechanism?

Answer: Competitive opioid receptor antagonism

Naloxone competitively antagonizes mu, kappa, and delta opioid receptors, rapidly reversing opioid-induced respiratory depression, sedation, and analgesia.

Which induction agent is contraindicated in patients with porphyria?

Answer: Thiopental

Barbiturates such as thiopental induce delta-aminolevulinic acid (ALA) synthase, precipitating acute porphyric crises in susceptible patients.

Etomidate is preferred for induction in hemodynamically unstable patients primarily because it does what?

Answer: Minimally affects cardiovascular function

Etomidate provides reliable hypnosis with minimal cardiovascular depression, making it the induction agent of choice for patients with cardiovascular compromise.

Which volatile agent is most associated with compound A formation and potential nephrotoxicity, particularly at low fresh gas flows?

Answer: Sevoflurane

Sevoflurane reacts with carbon dioxide absorbents (especially desiccated barium hydroxide lime) to produce compound A, a nephrotoxic degradation product.

The addition of epinephrine to local anesthetic solutions for peripheral nerve blocks primarily serves what purpose?

Answer: Prolongs duration of block by causing vasoconstriction

Epinephrine causes local vasoconstriction, reducing vascular absorption of the local anesthetic and thereby prolonging the duration of the nerve block.