Ketamine vs Haloperidol for Prehospital Sedation in the Agitated Patient
The Article: A prospective study of ketamine versus haloperidol for severe prehospital agitation. Cole et al. (2016)Clinical Tox. 54(7):556-62.
The Idea: To determine if IM ketamine is superior to IM haloperidol for sedation in undifferentiated agitated patients in the prehospital setting.
The Study: A single-center, nonrandomized, unblinded study comparing 5mg/kg IM ketamine to 10mg IM haloperidol in undifferentiated severely agitated patients in the prehospital setting. Inclusion criteria included all patients in the study hospital’s EMS system requiring chemical sedation for severe acute undifferentiated agitation, defined as an Altered Mental Status Scale (AMSS) score of +2 or +3. Exclusion criteria included obviously gravid women, persons who appeared or were known to be under 18, and patients with “profound agitation” defined as an AMSS score of +4. Data was collected over 12 months; for the first 3 months of the study all patients meeting inclusion criteria were given 10mg IM haloperidol. During the subsequent 6 months, the patients received 5mg/kg IM ketamine calculated by paramedics using estimated weight. For the final 3 months, the patients received 10mg IM haloperidol. The primary study outcome was time to adequate sedation. Secondary outcomes included re-dosing in the prehospital setting, rate of adverse side effects and rate of intubation.
The Findings: One hundred forty-six patients were included in the study, 64 in the ketamine group and 82 in the haloperidol group. The ketamine group achieved a significantly faster time to adequate sedation (5 min vs 17 min, P < 0.0001) and required significantly less additional sedation in the prehospital setting compared to the haloperidol group. However, the ketamine group also demonstrated significantly higher complication rates (49% vs 5%, P < 0.0001) and intubation rates (39% vs 4%, P < 0.0001). The most common complications in the ketamine group were hypersalivation (38%) and emergence reaction (10%). The most common indication for intubation in the ketamine group was “Not Protecting Airway, NOS”, and the most common indication for intubation in the haloperidol group was “Refractory Agitation”.
The Takeaway: Ketamine was superior to haloperidol for time to adequate sedation and avoidance of re-dosing in the prehospital setting, but the side-effect profile and intubation rate favored haloperidol in this small, single-center, nonrandomized and unblinded study.