What is the typical induction dose of propofol in adults and what is a common hemodynamic effect?

• A. 2-2.5 mg/kg; can cause hypotension due to decreased systemic vascular resistance.
• B. 0.2-0.25 mg/kg; causes hypertension.
• C. 5-6 mg/kg; no hemodynamic effect.
• D. 0.5-1 mg/kg; increases heart rate.

Answer: (A)

Propofol works as a rapid IV induction agent by causing dose-dependent vasodilation and mild myocardial depression, which together lower the blood pressure. The usual induction dose in adults is about 2 to 2.5 mg/kg, which reliably produces loss of consciousness quickly. At this dosing range, the most consistent hemodynamic effect is a drop in systemic vascular resistance that leads to hypotension, though heart rate can vary and some patients may experience bradycardia.

Smaller doses like 0.2–0.25 mg/kg are not sufficient to induce anesthesia and would not cause the typical hypotensive response; instead, they would result in insufficient sedation and delay induction. A much larger dose, such as 5–6 mg/kg, would cause deeper anesthesia with more pronounced cardiovascular depression and isn’t the standard induction range. A dose of 0.5–1 mg/kg is incomplete for induction and, while it may cause some hemodynamic changes, is not the characteristic induction dose nor the one most associated with the classic vasodilatory hypotension of propofol.