A prospective, double-blind, randomized trial of midazolam versus haloperidol versus lorazepam in the chemical restraint of violent and severely agitated patients

Abstract

Objectives: To determine if midazolam is superior to lorazepam or haloperidol in the management of violent and severely agitated patients in the emergency department. Superiority would be determined if midazolam resulted in a significantly shorter time to sedation and shorter time to arousal.

Methods: This was a randomized, prospective, double-blind study of a convenience sample of patients from an urban, county teaching emergency department. Participants included 111 violent and severely agitated patients. Patients were randomized to receive intramuscular midazolam (5 mg), lorazepam (2 mg), or haloperidol (5 mg).

Results: The mean (+/-SD) age was 40.7 (+/-13) years. The mean (+/-SD) time to sedation was 18.3 (+/-14) minutes for patients receiving midazolam, 28.3 (+/-25) minutes for haloperidol, and 32.2 (+/-20) minutes for lorazepam. Midazolam had a significantly shorter time to sedation than lorazepam and haloperidol (p < 0.05). The mean difference between midazolam and lorazepam was 13.0 minutes (95% confidence interval [95% CI] = 5.1 to 22.8 minutes) and that between midazolam and haloperidol was 9.9 minutes (95% CI = 0.5 to 19.3 minutes). Time to arousal was 81.9 minutes for patients receiving midazolam, 126.5 minutes for haloperidol, and 217.2 minutes for lorazepam. Time to arousal for midazolam was significantly shorter than for both haloperidol and lorazepam (p < 0.05). The mean difference in time to awakening between midazolam and lorazepam was 135.3 minutes (95% CI = 89 to 182 minutes) and that between midazolam and haloperidol was 44.6 minutes (95% CI = 9 to 80 minutes). There was no significant difference over time by repeated-measures analysis of variance between groups in regard to changes in systolic and diastolic blood pressure (p = 0.8965, p = 0.9581), heart rate (p = 0.5517), respiratory rate (p = 0.8191), and oxygen saturation (p = 0.8991).

Conclusions: Midazolam has a significantly shorter time to onset of sedation and a more rapid time to arousal than lorazepam or haloperidol. The efficacies of all three drugs appear to be similar.