Which volatile anesthetic is most likely to reduce arterial pressure by decreasing cardiac output rather than systemic vascular resistance?

Which volatile anesthetic is most likely to reduce arterial pressure by decreasing cardiac output rather than systemic vascular resistance?

• A. Halothane
• B. Sevoflurane
• C. Desflurane
• D. Isoflurane

Answer: (A)

The key concept is how arterial pressure changes with volatile anesthetics: mean arterial pressure depends on both cardiac output and systemic vascular resistance. Halothane is known for its strong depressant effect on the heart, reducing contractility and often causing bradycardia, which lowers cardiac output. Because the fall in arterial pressure with halothane primarily comes from this decrease in CO rather than from vasodilation, halothane is the one most likely to reduce arterial pressure by decreasing cardiac output. The other agents mainly lower blood pressure by dilating vessels and decreasing systemic vascular resistance, with less impact on cardiac output at typical clinical doses.

The key concept is how arterial pressure changes with volatile anesthetics: mean arterial pressure depends on both cardiac output and systemic vascular resistance. Halothane is known for its strong depressant effect on the heart, reducing contractility and often causing bradycardia, which lowers cardiac output. Because the fall in arterial pressure with halothane primarily comes from this decrease in CO rather than from vasodilation, halothane is the one most likely to reduce arterial pressure by decreasing cardiac output. The other agents mainly lower blood pressure by dilating vessels and decreasing systemic vascular resistance, with less impact on cardiac output at typical clinical doses.