The effect of intravenous milrinone in adult critically ill patients: A meta-analysis of randomized clinical trials

Background: Milrinone is widely used for enhancing myocardial contractility, however, there is inadequate data to suggest whether it is preferable to other inotropic agents in critically ill patients. To observe the effect of milrinone on prognosis in adult critically ill patients, we conducted this meta-analysis.Methods: A search of the following databases was conducted: Medline, Elsevier, Cochrane Central Register of Controlled Trials and Web of Science databases, and eligible randomized controlled trials including adult critically ill patients were screened. Two reviewers collected data separately, information was retrieved including study design, center number, sample size, gender, age, intervention and outcome. Data were analyzed using methods recommended by the Cochrane Collaboration Review Manager 4.2 software. Random errors were evaluated by trial sequential analysis (TSA).Results: Twenty studies including 2036 critically ill patients which compared milrinone with control group were enrolled. When compared to control group, there was no significant difference of all-cause mortality, while the incidence of ventricular arrhythmia decreased significantly in patients with cardiac surgery who using milrinone, but not in patients with cardiac dysfunction and shock. There was no significant reduction in the incidence of myocardial infarction and no improvement of hemodynamic parameters in the milrinone group. TSA indicated lack of firm evidence for a beneficial effect.Conclusion: The meta-analysis showed when compared with control group, although no significant reduction in mortality and the incidence of myocardial infarction was found in the milrinone group, the incidence of ventricular arrhythmia decreased significantly in patients with cardiac surgery. More randomized controlled trials are needed to determine the reliable and conclusive evidence for milrinone's effects.