Comparative Effectiveness and Safety Between Milrinone or Dobutamine as Initial Inotrope Therapy in Cardiogenic Shock

Abstract

Inotropes are an integral component of the early stabilization of the patient presenting with cardiogenic shock. Despite years of clinical experience with the 2 most commonly used inotropes, dobutamine and milrinone, there remains limited data comparing outcomes between the two. We conducted a retrospective review to compare the effectiveness and safety of milrinone or dobutamine for the initial management of cardiogenic shock. Adult patients with cardiogenic shock regardless of etiology who received initial inotrope therapy with either milrinone (n = 50) or dobutamine (n = 50) and did not receive mechanical circulatory support were included. The primary end point was the time to resolution of cardiogenic shock. Changes in hemodynamic parameters from baseline and adverse events were also assessed. Resolution of shock was achieved in similar numbers in both the groups (milrinone 76% vs dobutamine 70%, P = .50). The median time to resolution of shock was 24 hours in both groups ( P = .75). There were no differences in hemodynamic changes during inotrope therapy, although dobutamine trended toward a greater increase in cardiac index. Arrhythmias were more common in patients treated with dobutamine than milrinone, respectively (62.9% vs 32.8%, P < .01), whereas hypotension occurred to a similar extent in both groups (milrinone 49.2% vs dobutamine 40.3%, P = .32). The use of concomitant vasoactive medications, dosage required, and duration of therapy did not differ between groups. There was no difference in the overall rate of discontinuation due to adverse event; however, milrinone was more commonly discontinued due to hypotension (13.1% vs 0%, P < .01) and dobutamine was more commonly discontinued due to arrhythmia (0% vs 11.3%, P < .01). Milrinone and dobutamine demonstrated similar effectiveness and safety profiles but with differences in adverse events. The choice of milrinone or dobutamine as initial inotrope therapy for cardiogenic shock may depend more on tolerability of adverse events.