To determine whether epinephrine might prove to be a cost-effective substitute for dobutamine, two 8-minute infusions of either epinephrine (10 and 30 ng/kg/min, n = 28) or dobutamine (2.5 and 5 pg/kg/min, n = 24) were administered to 52 patients recovering in the intensive care unit (ICU) after aortocoronary bypass (CABG) surgery. At the higher dose, both drugs significantly (P < .05) increased cardiac index (CI), epinephrine from 2.8 ± 0.1 at baseline to 3.3 ± 0.1 L/min/m2, and dobutamine from 3.2 ± 0.1 at baseline to 4.1 ± 0.2 L/min/m2. Epinephrine increased CI significantly less than dobutamine. Both drugs significantly increased stroke volume index (SVI), epinephrine from 32 ± 1 at baseline to 36 ± 1 mL/beat/m2, and dobutamine from 36 ± 1 at baseline to 40 ± 2 mL/beat/m2. At the higher dose, the effects of the two drugs on SVI were indistinguishable. On the other hand, while the higher dose of both drugs significantly increased heart rate (HR), epinephrine from 88 ± 2 at baseline to 90 ± 2 beats/min and dobutamine from 89 ± 2 at baseline to 105 ± 3 beats/min, the increase following the higher dose of dobutamine was significantly greater than that seen after epinephrine. Effects of the two drugs on mean arterial pressure, central venous pressure, pulmonary artery occlusion pressure, systemic vascular resistance, pulmonary vascular resistance, and left-ventricular stroke work did not significantly differ. Similar results were obtained in the subset of patients with baseline CI less than 3 L/min/m2 who more closely resembled patients who might acutely require inotroppc drug administration. The wholesale cost of one ampule of dobutamine (250 mg) is more than 150 times that of epinephrine (1 mg). It is concluded that when SV was increased comparably by either epinephrine or dobutamine, epinephrine increased HR less than dobutamine. Thus, epinephrine may represent a cost-effective substitute for dobutamine, and its use may be associated with reduced tachycardia in the ICU after CABG.
- cardiac surgery
- heart failure