Comparative systemic and regional hemodynamic effects of dopamine and dobutamine.

Dopamine and dobutamine are sympathomimetic amines with divergent peripheral vascular actions. The renal, mesenteric, and femoral vascular and total systemic hemodynamic effects of these amines were compared in pentobarbital-anesthetized dogs. Both agents increased myocardial contractility. Infusion rates of dopamine greater than 5 mug per kilogram per minute increased mean aortic pressure. Dobutamine increased mean aortic pressure. Dobutamine in creased the systolic pressure but did not alter mean aortic pressure. Dobutamine increased cardiac output more than dopamine. Dopamine infusions up to 10 mug per kilogram per minute increased renal and mesenteric blood flow and decreased vascular resistance. Dobutamine had negligible effects on the renal or mesenteric blood flow but produced dose-related increases in femoral blood flow. Dopamine did not significantly alter femoral hemodynamics. These results more clearly define the systemic and regional vascular hemodynamic effects of these agents.