CSFA Surgical Pharmacology and Anesthesia 4 — Questions and Answers
Question 1: Which intravenous anesthetic agent is preferred for patients with a history of postoperative nausea and vomiting (PONV) due to its antiemetic properties?
- Ketamine
- Etomidate
- Propofol (Correct answer)
- Midazolam
Correct answer: Propofol
Propofol has intrinsic antiemetic properties and is associated with lower rates of PONV compared to other induction agents and volatile anesthetics.
Question 2: Ondansetron is frequently used perioperatively to prevent PONV. Its mechanism of action involves blocking which receptor?
- Dopamine D2
- Histamine H1
- Serotonin 5-HT3 (Correct answer)
- Muscarinic M1
Correct answer: Serotonin 5-HT3
Ondansetron is a selective 5-HT3 receptor antagonist that blocks serotonin-mediated signals in the chemoreceptor trigger zone and GI tract.
Question 3: The CSFA notices the surgical field is oozing excessively. The surgeon requests topical thrombin. Which statement about topical thrombin is CORRECT?
- It must be injected IV to work effectively
- It converts fibrinogen to fibrin at the surgical site (Correct answer)
- It is safe to inject intravascularly
- It permanently dissolves blood clots
Correct answer: It converts fibrinogen to fibrin at the surgical site
Topical thrombin converts fibrinogen to fibrin locally, promoting clot formation at the site of bleeding; it must never be injected intravascularly.
Question 4: Which benzodiazepine is most commonly used for preoperative anxiolysis and procedural sedation due to its short duration and amnestic properties?
- Diazepam
- Lorazepam
- Midazolam (Correct answer)
- Clonazepam
Correct answer: Midazolam
Midazolam is preferred for perioperative use because of its short half-life, reliable anxiolysis, and potent anterograde amnesia.
Question 5: A patient with known renal failure requires a non-depolarizing neuromuscular blocker. Which agent is SAFEST because it undergoes Hofmann elimination (non-organ-dependent degradation)?
- Vecuronium
- Pancuronium
- Cisatracurium (Correct answer)
- Rocuronium
Correct answer: Cisatracurium
Cisatracurium undergoes Hofmann elimination (spontaneous degradation at physiological pH and temperature), making it safe in renal or hepatic failure.
Question 6: Tranexamic acid (TXA) is used intraoperatively primarily to:
- Reverse heparin anticoagulation
- Inhibit fibrinolysis and reduce surgical blood loss (Correct answer)
- Increase platelet aggregation directly
- Promote vasodilation and reduce blood pressure
Correct answer: Inhibit fibrinolysis and reduce surgical blood loss
Tranexamic acid inhibits fibrinolysis by blocking plasminogen activation, thereby stabilizing clots and reducing intraoperative blood loss.
Question 7: Which drug is the antidote for benzodiazepine overdose or excessive sedation?
- Naloxone
- Neostigmine
- Flumazenil (Correct answer)
- Physostigmine
Correct answer: Flumazenil
Flumazenil is a competitive benzodiazepine receptor antagonist that rapidly reverses sedation, amnesia, and respiratory depression caused by benzodiazepines.
CSFA Surgical Pharmacology and Anesthesia 4
Which intravenous anesthetic agent is preferred for patients with a history of postoperative nausea and vomiting (PONV) due to its antiemetic properties?