A retrospective analysis of ketamine administration by Critical Care Paramedics in a pre-hospital care setting

ABSTRACT Objective: This project aims to describe pre-hospital use of Ketamine in trauma by South East Coast Ambulance Service Critical Care Paramedics and evaluate the occurrence of any side effects or adverse events. Methods: A retrospective analysis of patients receiving pre-hospital ketamine for trauma between 16th March 2013 and 30th April 2017. Administrations were identified from Advanced Life Saving Intervention and Procedure reports submitted by the clinician and, later, from an electronic database. Each was scrutinised for patient demographics, indication, doses and reports of side effects or adverse events. Results: A total of 510 administrations were identified. Thirty-four of these were excluded due to a lack of completeness, ketamine being drawn and not administered or the administering clinician not being a Critical Care Paramedic. A further twenty-seven were excluded due to being given for a non-traumatic reason. Of the remaining 449 administrations, males accounted for 302 (67.3%) compared to 147 (32.7%) females. The average age was 45.26 with women older (53.2 years vs. 41.4 years). The mean dose was 32.63mg (IQR 20; 5-180mg). Isolated lower limb trauma was the most common indication (228/449; 50.8%). Notable side effects were reported on 15 occasions with one adverse event. The mean dose for side effect was 29.3mg. Males received a higher dose when exhibiting a side effect (31.90mg vs. 26.43mg). Conclusions: Critical Care Paramedics within a well governed system are able to safely administer ketamine within an approved dosing regimen under a Patient Group Direction. Mean doses are in keeping with nationally approved guidelines. The demographics represent the national trauma statistics. Reported side effects were within the described frequencies in the British National Formulary, and reported in other studies. Numbers Needed to Harm (NNH) also appear acceptable given that the side effects are easy to manage within a Critical Care Paramedic’s scope of practice. However, the project has significant limitations and so further, prospective research is required.