Etomidate vs Ketamine-Propofol for Induction of Anesthesia in Coronary Artery Bypass Grafting: An Updated Systematic Review and Meta-Analysis

Abstract

Background: Etomidate has minimal cardiovascular depressant effects at the cost of endogenous cortisol production suppression, whereas propofol has vasodilatory and myocardial depressant properties, which may be poorly tolerated in the cardiac surgical population. To offset the undesirable effects of propofol, ketamine can be co-administered to harness its cardiac stimulatory properties. Though etomidate is a more cardio-stable induction agent than propofol, its superiority over the combination of propofol and ketamine-colloquially known as "ketofol"-remains controversial. Methods: United States National Library of Medicine Database (MEDLINE) and Excerpta Medica Database (EMBASE) were searched for randomized controlled trials published since 2010 comparing etomidate and ketofol relative to propofol alone for induction of general anesthesia for coronary artery bypass grafting (CABG). Key data collected included post-induction nadir mean arterial pressure (MAP), heart rate, cardiac index, systemic vascular resistance (SVR), and serum cortisol levels at 24 hours postoperatively. Variables were compared by calculating a weighted mean difference (WMD) [95% confidence interval (CI)]. Results: This analysis included 15 studies (1125 patients). Anesthetic induction with etomidate was associated with a higher nadir MAP and SVR compared to ketofol during the peri-induction period by WMD 4.77 mmHg [95% CI 0.31, 9.23, P = 0.04] and 42.22 dynes/cm⁵ [95% CI 0.49-83.94, P = 0.05]. However, there was no difference in the frequency of needed boluses of vasopressors or fluids for peri-induction hypotension. Conclusions: Though etomidate appears to provide a superior hemodynamic profile compared to ketofol, both agents require similar degrees of clinical response to hypotension during the induction of CABG surgery patients.

Keywords: coronary artery bypass grafting; coronary artery bypass surgery; etomidate; induction; ketamine; ketofol; propofol.