Intraoperative Ketamine for Analgesia Post-Coronary Artery Bypass Surgery: A Randomized, Controlled, Double-Blind Clinical Trial.

OBJECTIVES:To determine whether the administration of ketamine during coronary artery bypass grafting (CABG) surgery leads to a reduction in the quantity of opioids required over the first 48 hours after surgery.DESIGN:Randomized, controlled, double-blind clinical trial.SETTING:Single university academic center.PARTICIPANTS:Patients undergoing CABG surgery with a normal left ventricular ejection fraction.INTERVENTIONS:Ketamine administered intravenously as a bolus dose of 0.5 mg/kg before skin incision, followed by an infusion of 0.5 mg/kg/h until the end of surgery.MEASUREMENTS AND MAIN RESULTS:One hundred eighty-three patients were screened, and 80 patients were randomized. Baseline characteristics were similar between the 2 groups. The intervention group received 53.6 mg (95% confidence interval [CI] 47.1-60.1 mg) of morphine equivalents in the first 48 hours after surgery, whereas the placebo group received 55.7 mg (95% CI 48.4-63.1 mg) over the same time period (p = 0.66). No significant difference was noted in morphine equivalents over the first 6, 12, or 24 hours postoperatively or in maximum, minimum, or average pain scores on postoperative days 1 or 2.CONCLUSIONS:The administration of ketamine during CABG surgery did not result in reduced opioid consumption or pain scores postoperatively.