Etomidate versus Ketamine as Prehospital Induction Agent in Patients with Suspected Severe Traumatic Brain Injury

Abstract

Introduction Severe traumatic brain injury (TBI) is a leading cause of morbidity and mortality among young people around the world. Prehospital care focusses on the prevention and treatment of secondary brain injury and commonly includes tracheal intubation after induction of general anesthesia. The choice of induction agent in this setting is controversial. We therefore investigated the association between the chosen induction medication etomidate versus S(+)-ketamine , and the 30-day mortality in patients with severe TBI who received prehospital airway management in the Netherlands. Methods We conducted a retrospective analysis of the prospectively collected observational data of the BRAIN-PROTECT cohort study. Patients with suspected severe TBI, who were transported to a participating trauma center and who received etomidate or S(+)-ketamine for prehospital induction of anesthesia for advanced airway management were included. Statistical analyses were performed with multivariable logistic regression and Inverse Probability of Treatment Weighting analysis. Results In total, 1457 patients were eligible for analysis. No significant association between the administered induction medication and 30-day mortality was observed in unadjusted analyses (etomidate 32.9% mortality versus S(+)-ketamine 33.8% mortality, p= 0.716, OR 1.04, 95% CI 0.83 to 1.32, p= 0.711) as well as after adjustment for potential confounders (OR 1.08, 95% CI 0.67 to 1.73, p= 0.765; risk difference 0.017, 95% CI -0.051 to 0.084, p= 0.686). Likewise, in planned subgroup analyses for patients with confirmed TBI and patients with isolated TBI, no significant differences were found. Consistent results were found after multiple imputation of missing data. Conclusions We found no evidence for an association between the use of etomidate or S(+)-ketamine as an anesthetic agent for intubation in patients with TBI and mortality after 30 days in the prehospital setting, suggesting that the choice of induction agent may not influence patient mortality rate in this population.