Amrinone and milrinone produced similar increases in cardiac index (48% vs 52%, P=NS) and comparable overall hemodynamic effects in adult patients immediately after cardiopulmonary bypass.
RCT (n=44)
blind
randomized
Yes
Does amrinone compared to milrinone improve hemodynamic parameters in patients undergoing elective cardiac surgery?
Amrinone and milrinone produce similar hemodynamic improvements after cardiopulmonary bypass, suggesting the choice between them can be based on nonhemodynamic considerations such as cost.
Absolute Event Rate: 48% vs 52%
p-value: p=NS
UNLABELLED: Amrinone and milrinone are phosphodiesterase inhibitors with positive inotropic effects useful for the treatment of ventricular dysfunction after cardiac surgery. Forty-four patients undergoing elective cardiac surgery at four centers received either amrinone (n = 22) or milrinone (n = 22) in a randomized, blind fashion. Immediately after separation from cardiopulmonary bypass (CPB), two bolus doses of either amrinone 0.75 mg/kg or milrinone 25 microg/kg were administered over 30 s, separated by 5 min. Hemodynamic measurements were recorded before each dose and at the end of the 10-min study. Both amrinone and milrinone increased the cardiac index (48% vs 52%, P = not significant NS for amrinone and milrinone, respectively). There was a small increase in mean arterial pressure (MAP) after amrinone administration (from 68 +/- 3 to 72 +/- 3 mm Hg at 10 min, P < 0.05) with no significant change in MAP after milrinone administration. Central venous pressure was significantly higher in the amrinone group at baseline and 5 min (12 vs 10 mm Hg and 11 vs 10 mm Hg, respectively; P < 0.05). Systemic and pulmonary vascular resistances decreased significantly and to a similar extent after either amrinone or milrinone administration. Phenylephrine was required in 11 of 22 patients receiving amrinone and in 11 of 22 patients receiving milrinone to maintain arterial blood pressure. The proportion of patients requiring an intravascular volume infusion (15 of 22 vs 17 of 22, P = NS) and the total fluid volume infused were similar (402 +/- 57 vs 350 +/- 49 mL, P = NS for amrinone and milrinone, respectively). Amrinone and milrinone seem to have similar hemodynamic effects after CPB, with the exception of blood pressure, although the need for vasopressor support of blood pressure did not differ. Selection between these two drugs may include nonhemodynamic considerations such as cost. IMPLICATIONS: Amrinone and milrinone are drugs that improve cardiac contraction. Their effects have never been directly compared in patients. We found that amrinone and milrinone produced similar hemodynamic effects in adult patients undergoing cardiac surgery. Choice between the two drugs can be based on nonhemodynamic considerations such as cost.
Rathmell et al. (1998) conducted an RCT in elective cardiac surgery (n=44). amrinone vs. milrinone (two bolus doses of 25 microg/kg over 30 s, separated by 5 min) was evaluated on increase in cardiac index (p=NS). Amrinone and milrinone produced similar increases in cardiac index (48% vs 52%, P=NS) and comparable overall hemodynamic effects in adult patients immediately after cardiopulmonary bypass.