Induction agents for emergency tracheal intubation in critically ill adults: a systematic review and network meta-analysis

BACKGROUND: Etomidate, ketamine, and propofol are all used as induction agents for emergency tracheal intubation in critically ill adults but it remains uncertain which agent should be preferable. METHODS: We searched MEDLINE and Embase (inception to December 2025) for randomized controlled trials comparing etomidate, ketamine, propofol, or ketamine-propofol combination (ketofol) for emergency or rapid sequence intubation in critically ill adults. We performed random-effects network meta-analysis using the frequentist framework. The primary outcome was short-term mortality (28-30 day, or ICU/in-hospital mortality when unavailable). Secondary outcomes included cardiovascular collapse, post-induction hypotension, vasopressor use, first-pass intubation success, and peri-intubation cardiac arrest. Certainty of evidence was assessed using the CINeMA framework. RESULTS: Nine trials (4,672 patients, four treatments) were included. Ketamine and etomidate probably result in similar mortality (OR 0.96, 95% CI 0.80-1.16; [Formula: see text] = 30%; moderate certainty). Evidence for other mortality comparisons was very uncertain: ketamine vs propofol (OR 1.53, 0.80-2.93; 1 trial; low certainty) and etomidate vs propofol (OR 0.63, 0.32-1.24; indirect only; very low certainty). Compared with etomidate, ketamine probably increases cardiovascular collapse (OR 1.44, 1.20-1.71; moderate certainty) and may increase post-induction hypotension (OR 1.34, 1.07-1.68; low certainty) and peri-intubation vasopressor use (OR 1.45, 1.21-1.74; low certainty). There was probably little or no difference in first-pass intubation success or cardiac arrest. CONCLUSIONS: Etomidate and ketamine probably result in similar mortality, but confidence intervals are compatible with clinically important differences in either direction-ketamine probably causes more peri-intubation hemodynamic instability. Beyond one trial, no randomized evidence exists for propofol in emergency intubation of critically ill adults.