Ketamine Versus Etomidate for Emergency Tracheal Intubation in Critically Ill Adults

Introduction/Background: Ketamine and etomidate are the most commonly used induction agents for emergency tracheal intubation in critically ill adults. However, their comparative cardiovascular safety remains uncertain. Research Questions/Hypothesis: To compare peri-intubation cardiovascular and mortality outcomes between ketamine and etomidate in randomized controlled trials. Methods/Approach: PubMed, Embase, and Cochrane databases were systematically searched for randomized controlled trials comparing ketamine and etomidate for endotracheal intubation in critically ill adults. Outcomes of interest included mortality, peri-intubation cardiac arrest, hypotension, and cardiovascular collapse. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using random-effects models. Statistical heterogeneity was assessed using the I 2 statistic, and leave-one-out sensitivity analyses were performed to evaluate the robustness of the results. Statistical analysis was performed using R (RStudio version 2026.01.0, Build 392). Results/Data: Five RCTs involving 4,028 critically ill patients (2,006 randomized to ketamine and 2,022 to etomidate) were included. Ketamine was not associated with significant differences in all-cause mortality (RR 0.95, 95% CI 0.84-1.07; I 2 =20%), peri-intubation cardiac arrest (RR 1.29, 95% CI 0.77-2.16; I 2 =0%), hypotension (RR 1.10, 95% CI 0.85-1.43; I 2 =0%), or cardiovascular collapse (RR 0.99, 95% CI 0.79-1.23; I 2 =0%) compared with etomidate. Sensitivity analyses yielded consistent results across all outcomes. Conclusion: Among critically ill adults undergoing emergency endotracheal intubation, ketamine and etomidate were associated with similar risks of mortality, peri-intubation cardiac arrest, hypotension, and cardiovascular collapse. Current randomized evidence does not support the superiority of either induction agent with respect to major cardiovascular or clinical outcomes.