Which narcotic causes the greatest decrease in myocardial contractility when given in high doses alone?

Which narcotic causes the greatest decrease in myocardial contractility when given in high doses alone?

• A. Morphine
• B. Meperidine
• C. Sufentanil
• D. Fentanyl

Answer: (B)

Opioids can affect heart muscle performance, and the extent of that effect rises with dose. In high doses given alone, some opioids cause more direct depression of the myocardium than others. The agents that are most hemodynamically stable—fentanyl and sufentanil—tend to preserve contractility because they produce analgesia with minimal direct myocardial depression and little histamine-related vasodilation. Morphine can reduce preload through histamine release, which alters hemodynamics but doesn’t typically depress contractility as strongly. Meperidine, however, has a greater tendency to produce direct negative inotropic effects on the myocardium when used in high doses without other drugs, leading to the greatest decrease in contractility among these options. This makes it the best answer for a scenario asking which narcotic most reduces myocardial contractility on high-dose administration.

Opioids can affect heart muscle performance, and the extent of that effect rises with dose. In high doses given alone, some opioids cause more direct depression of the myocardium than others. The agents that are most hemodynamically stable—fentanyl and sufentanil—tend to preserve contractility because they produce analgesia with minimal direct myocardial depression and little histamine-related vasodilation. Morphine can reduce preload through histamine release, which alters hemodynamics but doesn’t typically depress contractility as strongly. Meperidine, however, has a greater tendency to produce direct negative inotropic effects on the myocardium when used in high doses without other drugs, leading to the greatest decrease in contractility among these options. This makes it the best answer for a scenario asking which narcotic most reduces myocardial contractility on high-dose administration.