There are no published reports in Canada examining paramedic use of ketamine for highly agitated patients or excited delirium syndrome. We employed a Plan, Do, Study, Act (PDSA) quality improvement approach to evaluate the safety and effectiveness of advanced care paramedic administered intramuscular (IM) ketamine for patients with extreme agitation in the out-of-hospital setting.
Data were prospectively collected from July 2018 to January 2019 when advanced care paramedics with specific training administered IM ketamine as an alternative to midazolam. Paramedics used a clinical audit form to document the ketamine dose, patient response on the Richmond Agitation Sedation Scale (RASS) at time intervals, adverse effects, and any airway management interventions they performed.
Thirty-three patients received either 4 mg/kg or 5 mg/kg of ketamine. Combining data for both doses, the median change in RASS score at 5 minutes post-ketamine was 3 (range 0 to 8) and statistically significant for each dose. There were seven cases (21%) with reported adverse effects including SpO2 <90% (3/7), hypersalivation (3/7), trismus or teeth grinding (2/7), muscular rigidity (1/7) and laryngospasm (1/7). Statistical analysis confirmed that the incidence of adverse events was not dose dependent. Basic airway management was performed in one-third of all cases.
We piloted the implementation of ketamine for sedation in our paramedic system by employing a PDSA cycle. Ketamine 5 mg/kg IM provided effective control of acutely agitated patients with adequate sedation at 5 minutes post-delivery. Any adverse events that occurred as a result of IM ketamine were readily managed with basic airway management interventions.
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