Adverse events following emergent prehospital sedation of patients with behavioral emergencies: A retrospective cohort study

Background Patients presenting to emergency medical services (EMS) with behavioral emergencies may require emergent sedation to facilitate care, but concerns about sedation-related adverse events (AEs) exist. This study aimed to describe the frequency of AEs following emergent prehospital sedation with three types of sedative agents: ketamine, benzodiazepines and antipsychotics. Methods This retrospective cohort study included patients = 15 years who presented to 1031U.S. EMS agencies in calendar year 2019 with behavioral emergencies necessitating emergent prehospital sedation. Serious AEs (SAE) included cardiac arrest, invasive airway placement, and severe oxygen desaturation (< 75%). Less-serious AEs included positive pressure ventilation, any oxygen desaturation (< 90%), oropharyngeal or nasopharyngeal airway placement, and suctioning. The need for additional sedation was also assessed. Findings Of 7973 patients, 1996 received ketamine; 4137 received a benzodiazepine; 1532 received an antipsychotic agent; and 308 received an indeterminant agent. Cardiac arrest occurred in 11 patients (0 center dot 1%) and any SAE occurred in 165 patients (2 center dot 1%). Invasive airway placement was more frequent with ketamine (40, 2 center dot 0%) compared with benzodiazepines (17, 0 center dot 4%) or antipsychotics (3, 0 center dot 2%). Oxygen desaturation below 75% also occurred more frequently with ketamine (51, 2 center dot 6%) than with benzodiazepines (52, 1 center dot 3%) or antipsychotics (14, 0 center dot 9%). Patients sedated with ketamine were less likely to require additional sedation. Propensity-matching to minimize potential confounding between patient condition, sedative choice and AEs did not meaningfully alter the results. Interpretation Although SAEs were rare among patients receiving emergent prehospital sedation, prehospital clinicians should remain mindful of the potential risks and monitor patients closely. Copyright (c) 2022 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)