Halothane (flurothane) causes which cardiovascular effect?

• A. Vasoconstrictions
• B. No effect
• C. Increases contractility
• D. Myocardial depression

Answer: (D)

Halothane’s effect on the heart is myocardial depression. As a volatile anesthetic, it directly reduces the heart muscle’s contractility and lowers systemic vascular resistance, leading to decreased cardiac output and blood pressure. It does not cause vasoconstriction or increased contractility, and there is typically a notable depressant effect on the myocardium. (Note: it can also sensitize the heart to catecholamines, raising arrhythmia risk, but the main cardiovascular action is reduced contractility.)