Comparative systemic and regional hemodynamic effects of dopamine and dobutamine in patients with cardiomyopathic heart failure.

TLDR

In a single‑crossover study of 13 patients with severe cardiac failure, the authors compared the systemic and regional hemodynamic effects of dopamine and dobutamine. Dobutamine progressively increased cardiac output by raising stroke volume while lowering systemic and pulmonary vascular resistance and wedge pressure without altering heart rate, whereas dopamine only raised output at 4 µg/kg/min, increased pulmonary wedge pressure and premature ventricular contractions below 4 µg/kg/min, raised heart rate above 6 µg/kg/min, and during maintenance infusion did not sustain the hemodynamic and renal benefits that dobutamine maintained, indicating dobutamine has many advantages over dopamine in cardiac failure.

Abstract

Thirteen patients with severe cardiac failure underwent a single crossover study of dopamine and dobutamine in order to compare the systemic and regional hemodynamic effects of the two drugs. The dose-response data demonstrated that dobutamine (2.5--10 microgram/kg/min) progressively and predictably increases cardiac output by increasing stroke volume, while simultaneously decreasing systemic and pulmonary vascular resistance and pulmonary capillary wedge pressure. There was no change in heart rate or premature ventricular contractions (PVCs)/min at this dose range. Dopamine (2--8 microgram/kg/min) increased the stroke volume and cardiac output at 4 microgram/kg/min. Dopamine at less than 4 microgram/kg/min provided little additional increase in cardiac output and increased the pulmonary wedge pressure and the number of PVCs/min. At greater than 6 microgram/kg/min, dopamine increased heart rate. During the 24-hour maintenance-dose infusion of each drug (dopamine 3.7--4, dobutamine 7.3--7.7 microgram/kg/min), only dobutamine maintained a significant increase of stroke volume, cardiac output, urine flow, urine sodium concentration, creatinine clearance and peripheral blood flow. Renal and hepatic blood flow were not signfiicantly altered by the maintenance dose of either drug. Systemic and regional hemodynamic data suggest that dobutamine has many advantages over dopamine when infused in patients with cardiac failure.