Retrospective evaluation of ketamine versus droperidol on time to restraint removal in agitated emergency department patients

Abstract

Purpose: Acute agitation and violent behavior in the emergency department (ED) can lead to significant patient morbidity and contribute to the growing problem of workplace violence against health care providers. To our knowledge, there is no available literature directly comparing intramuscular ketamine to intramuscular droperidol in ED patients presenting with undifferentiated agitation. The purpose of this investigation was to compare the effectiveness and safety of these agents for acute agitation in the ED.

Methods: This was a retrospective observational study conducted at an urban, academic ED. The primary endpoint was time from the first dose of study medication to restraint removal. Safety endpoints included incidence of bradycardia (heart rate < 60 bpm), hypotension (systolic blood pressure < 90 mmHg), hypoxia (oxygen saturation < 90% or need for respiratory support), and incidence of intubation for ongoing agitation or respiratory failure.

Results: An initial 189 patients were screened, of which, 92 met inclusion criteria. The median time from initial drug administration to restraint removal was 49 min (IQR 30, 168) in the ketamine group and 43 min (IQR 30, 80) in the droperidol group (Median difference 6 min; 95% CI [-7, 26]). There was no significant difference in rates of bradycardia (3% vs 3%, 95% CI [-7%, 8%]), hypotension (0% vs 2%, 95% CI [-5%, 2%]), or hypoxia (7% vs 10%, 95% CI [-15%, 9%]) in the ketamine versus droperidol groups respectively. One patient in the ketamine group was intubated for ongoing agitation, and one patient in the droperidol group was intubated for respiratory failure.

Conclusions: Intramuscular droperidol and intramuscular ketamine were associated with similar times from drug administration to restraint removal in patients presenting to the ED with undifferentiated agitation. Prospective studies are warranted to evaluate IM droperidol and IM ketamine head-to-head as first line agents for acute agitation in the ED.

Keywords: Agitation; Droperidol; Emergency department; Ketamine; Restraints.