Evaluation of Safety and Efficacy of Prehospital Paramedic Administration of Sub-Dissociative Dose of Ketamine in the Treatment of Trauma-Related Pain in Adult Civilian Population

Abstract

Opiates are addicting and have a high potential for dependency. In the past decades, opiates remained the first-line pharmaceutical option of prehospital treatment for acute traumatic pain in the civilian population. Ketamine is an N-methyl-d-aspartate (NMDA) receptor antagonist that has analgesic properties and may serve as an alternative agent for the treatment of acute traumatic pain in prehospital settings. This study aims to assess the safety and efficacy of ketamine administration by paramedics in civilian prehospital settings for the treatment of acute traumatic pain. This was a prospective observational study in San Bernardino, Riverside and Stanislaus counties. Patients were included if they were > 15 years of age with complaints of traumatic or burn-related pain. Patients were excluded if they received opiates up to six hours prior to or concurrently with ketamine administration. The dose administered was 0.3 mg/kg intravenously over five minutes with a maximum dose of 30 mg. The option to administer a second dose was available to paramedics if the patient continued to have pain after 15 minutes following the first administration. Paired-T tests were conducted to assess the change in the primary outcome (pain score) and secondary outcomes (e.g. systolic blood pressure, pulse, and respiratory rate). P-value<0.05 was considered to be statistically significant. A total of 368 patients were included in the final analysis. The average age was 52.9 ± 23.1 years, and the average weight was 80.4 ± 22.2 kg. There was a statistically significant reduction in the pain score (9.13 ± 1.28 vs 3.7 ± 3.4, delta=5.43 ± 3.38, p<0.0001). Additionally, there was a statistically significant change in systolic blood pressure (143.42 ± 27.01 vs 145.65 ± 26.26, delta=2.22 ± 21.1, p=0.044), pulse (88.06 ± 18 vs 84.64 ± 15.92, delta= -3.42 ± 12.12, p<0.0001), and respiratory rate (19.04 ± 3.59 vs 17.74 ± 3.06, delta=-1.3 ± 2.96, p<0.0001). The current study suggested that paramedics are capable of safely identifying the appropriate patients for the administration of sub-dissociative doses of ketamine in the prehospital setting. Furthermore, the current study suggested that ketamine may be an effective analgesic in a select group of adult trauma patients.

Keywords: adult; civilian; ketamine; prehospital.

Figure 1. Patients Flow Chart