The Use of Prehospital Ketamine for Control of Agitation in a Metropolitan Firefighter-based EMS System

Abstract

Introduction. Prehospital personnel frequently encounter agitated, combative, and intoxicated patients in the field. In recent years, ketamine has been described as an effective sedative agent to treat such patients; however, a paucity of research exists describing the use of prehospital ketamine. The objective of this study was to provide a descriptive analysis of the Columbus Division of Fire's experience with utilizing ketamine in the prehospital setting. We hypothesized that ketamine administration improves patient condition, is effective at sedating patients, and does not result in endotracheal intubation in the prehospital setting or in the emergency department (ED). Methods. We conducted a retrospective cohort chart review of Columbus Division of Fire patient care reports and hospital records from destination hospitals in the central Ohio region between October 2010 and October 2012. All patients receiving ketamine administered by Columbus Division of Fire personnel for sedation were included. Patients 17 years and younger were excluded. The primary outcome was the percentage of patients noted to have an "improved" condition recorded in the data field of the patient care report. The secondary outcomes were the effectiveness of sedation and the performance of endotracheal intubation. Results. A total of 36 patients met inclusion criteria over the study period. Data were available on 35 patients for analysis. The mean IV dose of ketamine was 138 mg (SD = 59.5, 100-200). The mean IM dose of ketamine was 324 mg (SD = 120, 100-500). Prehospital records noted an improvement in patient condition after ketamine administration in 32 cases (91%, 95% CI 77-98%). Six patients required sedation post-ketamine administration either by EMS (2) or in the ED (4) (17%, 95% CI 6.5-34%). Endotracheal intubation was performed in eight (23%, 95% CI 10-40%) patients post-ketamine administration. Conclusion. We found that in a cohort of patients administered ketamine, paramedics reported a subjective improvement in patient condition. Endotracheal intubation was performed in 8 patients.

Ketamine for the Acute Management of Excited Delirium and Agitation in the Prehospital Setting

“…Patients treated with ketamine experienced more side effects and more frequent intubations (25 [39%]) when compared with haloperidol (3 [4%]). Despite only nine patients having acute alcohol intoxication and none receiving an additional benzodiazepine, the intubation rate of 39% for ketamine in this study was higher than previous reports . This finding did not appear to be related to the dose, despite the authors not reporting a maximum ketamine dose.…”

“…This may be attributed to the rapid onset of action of ketamine, the shortened length of transit time (mean transit time 8 min), and the reduced baseline agitation compared with other studies because patients with profound agitation (score of 4+ on the AMSS) were excluded. Patients treated with ketamine experienced more side effects and more frequent intubations (25 [39%]) when 22,23 This finding did not appear to be related to the dose, despite the authors not reporting a maximum ketamine dose. All intubations occurred within the emergency department (ED), and most physicians cited the reason for intubation as an "unprotected airway not otherwise specified," followed by hypersalivation, refractory agitation, apnea, and aspiration or vomiting.…”

“…Emergency medical service responders have extensive experience with IM midazolam because it is the preferred IM agent in the management of status epilepticus and has a rapid onset of action and short duration of action when compared with other benzodiazepines . Although some studies utilized midazolam as adjunct sedation, there is potential concern that such a practice may compound the risk of respiratory compromise . Protocols for ketamine use in the prehospital setting should also include atropine or glycopyrrolate for management of hypersalivation .…”

Retrospective Study of Midazolam Protocol for Prehospital Behavioral Emergencies

“…Despite being used since the 1960s, ketamine has only recently been evaluated for use in treating agitation in the prehospital and ED settings and has been shown to be effective in controlling agitated patients in several studies. [22][23][24] However, research on the use of ketamine in the prehospital setting has demonstrated hypoxia, increased secretions, and laryngospasm requiring intubation following ketamine administration. [22][23][24][25] In one of the largest studies to date evaluating ketamine for prehospital agitation, ketamine performed well in comparison to haloperidol in controlling agitation but with an intubation rate of 39%.…”

Controversies in the Care of the Acute Asthmatic in the Prehospital and Emergency Department Environments

“…There are studies documenting ketamine's successful and safe use in the prehospital arena for multiple indications from analgesia, to sedation for excited delirium, to the most common use, sedation for endotracheal intubation [49][50][51][52]. One case report described delayed recurrent laryngospasm onset after arrival at the hospital in a patient who had received 500 mg (5 mg/kg) intramuscularly (IM) for excited delirium [53].…”