Morphine Use in the Treatment of Acute Cardiogenic Pulmonary Edema and Its Effects on Patient Outcome: A Systematic Review

To analyze whether the use of morphine, as initial treatment in acute cardiogenic pulmonary edema (ACPE), has an impact in clinical outcomes and mortality. A systematic review of the literature was performed, including all the studies comparing clinical outcomes in patients with ACPE who were treated or not with morphine. Seven studies were selected, none of which were a randomized trial focused on answering the aim of this systematic review. The studies consisted of clinical trial secondary analysis assessing non-invasive ventilation in ACPE, one open non-randomized trial, two propensity score evaluations from large registries, and three clinical case reviews. Most of the studies showed unfavorable results with the use of morphine in terms of adverse events and mortality, and many of them were statistically significant. Finally, the ongoing MIdazolam versus MOrphine in acute cardiogenic pulmonary edema (MIMO) trial was specifically designed to compare the results of morphine use versus midazolam. The potential hemodynamic and sedative benefit of the use of morphine for vasodilatation and dyspnea amelioration may be opposed by an increase in mortality, ICU admission, and adverse events. Until there is a randomized clinical trial, the use of morphine for ACPE should be limited.