The use of ketamine in the prehospital setting has increased with EMS providers. Adverse effects of prehospital ketamine administration have not been well-established in the trauma population. The objective of this study was to evaluate the effects of pre-hospital ketamine on trauma patients presenting to a Level 1 trauma center. This study hypothesized that respiratory depression or oversedation from ketamine would increase the number of ED (Emergency Department) intubations.

A retrospective chart review of adult trauma patients receiving prehospital ketamine from 2016-2021 was performed. Patients with severe traumatic brain injuries were excluded. A 1:1 propensity match was performed of patients with similar demographics, injury severity, and mechanism of injury who did not receive prehospital ketamine. Univariate analyses were used to compare the groups. The primary outcome was the incidence of intubation in the Emergency Department.

Seventy-four trauma patients who received prehospital ketamine were identified. The average ketamine dose was 39 mg IV and 226.4 mg IM. 35.1% of patients received ketamine for pain while 29.7% received it for agitation. The ED intubation rate was higher in the prehospital ketamine group with 17.6% (n=13/74) requiring intubation as compared with 4.8% (n=3/63) who did not receive ketamine (p=0.03). Patients who required intubation in the ED had higher average doses of both IV/IO (37.7 +/- 4.8 mg vs. 55.0 +/- 24.2 mg) and IM ketamine (196.4 +/- 41.7 mg vs 290.0 +/- 41.3 mg).

ED intubation rate was higher in the ketamine group. Patients that were intubated had received higher ketamine doses on average. Further studies are needed to understand and refine prehospital dosing and indication protocols to allow for more efficacious utilization of pre-hospital ketamine in trauma patients. A multicenter trial is ongoing.