Objective: To test the hypothesis that sublingual captopril produces a more rapid improvement of acute pulmonary edema (APE) than does placebo, when added to a standard regimen of O2, nitrates, morphine, and furosemide.
Methods: Prospective, randomized, double-blind, placebo-controlled clinical trial in an urban teaching hospital ED. Adults brought to the ED with APE were given captopril or placebo sublingually. Every 5 minutes a clinical APE distress score (APEX) was obtained.
Results: Over the first 40 minutes of treatment, the mean APEXs were significantly better for the patients given captopril [p < 0.001, F = 14.5, one-way (repeated-measures) analysis of variance (ANOVA)]. At 30 minutes, the patients given captopril had a mean APEX improvement of 43% (i.e., to 57% of initial distress); the group given the current standard regimen plus placebo improved only 25% (i.e., to 75% of initial distress; p = 0.03, multiway ANOVA). In addition, there was less respiratory failure necessitating mechanical ventilation in the captopril patients (9%) vs the placebo patients (20%), which did not achieve significance (p = 0.10, Fisher's exact test).
Conclusion: In APE, the addition of sublingual captopril to the standard regimen of O2, nitrates, morphine, and furosemide produces more rapid clinical improvement than does the standard regimen alone.