108 Ketamine as an Induction Agent in Emergency Department Intubation: Prospective Observational Multi-Center Study in Japan

Abstract

Ketamine is considered as the induction agent of choice in emergent airway management in hemodynamically compromised patients. However, clinical data of the use of ketamine in emergency department (ED) intubation are sparse. We compared the success rate of ED intubation and hemodynamic parameters among patients who underwent ED intubation with ketamine, benzodiazepine, and propofol. A secondary analysis of the data from the Japanese Emergency Airway Network (JEAN) two study, a prospective observational multicenter study of 13 academic and community EDs that was designed to characterize the current ED airway management across Japan during between April 2012 and June 2014. Data fields included patient demographics, primary indication for intubation, difficult airway scores, method of intubation, device, all medications used to facilitate intubation, number of attempts, adverse events, intubator characteristics, and pre- and post-intubation vital signs. All adult patients (≥15-year-old) who underwent oral intubation with ketamine, benzodiazepine, and propofol were eligible for the analyses. The primary outcome was success rate on the first attempt. The secondary outcome was the difference between pre- and post-intubation systolic blood pressure (post-intubation systolic blood pressure minus pre-intubation systolic blood pressure). The registry recorded 3,693 intubations (capture rate 96%) and 1,192 were eligible for the analysis. 172 patients (14%) underwent intubation with ketamine, 748 (63%) with benzodiazepine, and 272 (23%) with propofol. The success rates on first attempt of intubation with ketamine, with benzodiazepine, and with propofol were respectively 68% (95% confidence interval [CI], 60%-75%), 70% (95% CI, 66%-73%), and 69% (95% CI, 63%-74%). In the multivariable analysis adjusting for age, sex, body mass index, primary indication for intubation, difficult airway score, method of intubation, device, and specialties and training level of intubator, the success rate of intubation with ketamine did not show significant difference when compared to intubation with benzodiazepine (odds ratio [OR], 0.79; 95% CI, 0.54-1.16; P = .23) and propofol (OR, 0.71: 95% CI, 0.46-1.10: P = .12). The differences between pre- and post-intubation systolic blood pressure was 9.3 mmHg (standard deviation [SD], 34.2) with ketamine, −5.1 mmHg (SD, 38.9) with benzodiazepine, and −10.4 mmHg (SD, 39.5) with propofol. After adjusting for potential confounders, the differences between pre- and post-intubation systolic blood pressure were 11.5 mmHg (95%CI, 7.1 mmHg-16.0 mmHg) with ketamine, −3.9 mmHg (95% CI, −7.1 mmHg- [−0.7 mmHg]) with benzodiazepine, and −7.7 mmHg (95% CI, −11.6 mmHg- [−3.8 mmHg]) with propofol (P < .01). In this multicenter observational study, we found no significant differences in the success rate on first attempt among intubations with ketamine, benzodiazepine, and propofol but did the higher difference between pre- and post-intubation systolic blood pressure in intubation with ketamine than those with benzodiazepine and propofol.