How does propofol primarily affect systemic vascular resistance and cardiac output?

How does propofol primarily affect systemic vascular resistance and cardiac output?

• A. Increases heart rate only.
• B. Causes vasodilation, reducing systemic vascular resistance and often decreasing preload; may also decrease cardiac output.
• C. Increases SVR and increases CO.
• D. Has no effect on vascular tone.

Answer: (B)

Propofol mainly causes systemic vasodilation, which lowers systemic vascular resistance. This vasodilation comes from both a reduction in sympathetic tone and a direct relaxing effect on vascular smooth muscle. As the veins dilate, venous return to the heart falls, reducing preload. With less blood filling the heart, stroke volume tends to drop, and cardiac output may decrease, especially during induction when compensatory mechanisms don’t fully offset these changes. Some patients may experience a reflex increase in heart rate, but the overall effect on CO is typically a decrease or a maintenance at a lower level, not an increase.

Propofol mainly causes systemic vasodilation, which lowers systemic vascular resistance. This vasodilation comes from both a reduction in sympathetic tone and a direct relaxing effect on vascular smooth muscle. As the veins dilate, venous return to the heart falls, reducing preload. With less blood filling the heart, stroke volume tends to drop, and cardiac output may decrease, especially during induction when compensatory mechanisms don’t fully offset these changes. Some patients may experience a reflex increase in heart rate, but the overall effect on CO is typically a decrease or a maintenance at a lower level, not an increase.