The following is a summary of “Effects of MIdazolam versus MOrphine in acute cardiogenic pulmonary edema and chronic obstructive pulmonary disease: An analysis of MIMO trial,” published in the November 2023 issue of Emergency Medicine by Domínguez-Rodríguez, et al.

Chronic obstructive pulmonary disease (COPD) is a significant comorbidity in heart failure, and the MIMO trial previously demonstrated that patients with acute cardiogenic pulmonary edema (ACPE) treated with midazolam experienced fewer serious adverse events (AEs) than those treated with morphine. 

For a post hoc analysis, researchers sought to investigate whether the presence or absence of COPD influences the observed reduced risk of midazolam compared to morphine.

Patients over 18 years old clinically diagnosed with ACPE and experiencing dyspnea and anxiety were randomly assigned (1:1) upon arrival at the emergency department to receive either intravenous midazolam or morphine. This post hoc analysis calculated the relative risk (RR) of serious AEs for patients with and without COPD. The Cochran-Mantel-Haenszel interaction test was employed to assess whether COPD had a modifying effect on the reduced risk of serious AEs in the midazolam arm compared to morphine.

Among the 111 randomized patients, 25 (22.5%) had a history of COPD. Patients with COPD were more frequently male and had a history of previous heart failure episodes compared to those without COPD. In the COPD group, the RR for serious AEs in the midazolam versus morphine arm was 0.36 (95% CI, 0.1–1.46). The RR for the group without COPD was 0.44 (95% CI, 0.22–0.91). Importantly, the presence of COPD did not alter the reduced risk of serious adverse events observed in the midazolam arm compared to morphine (P for interaction = 0.79).

The decreased risk of serious AEs with midazolam compared to morphine is consistent among patients both with and without COPD.

Source: sciencedirect.com/science/article/abs/pii/S0735675723004667