Postoperative delirium after coronary artery bypass graft surgery: Dexmedetomidine infusion alone or with the addition of oral melatonin

Introduction: Postoperative delirium is a common complication of cardiac surgery. This study aimed to assess the effect of supplementing dexmedetomidine infusion with oral melatonin in prevention of postoperative delirium after coronary artery bypass graft surgery.Methods: 110 patients of both sexes above 60 years of age were included. Anesthetic management was standardized. Patients were randomly allocated into one of the two study groups, dexmedetomidine/melatonin (DM) group or dexmedetomidine (D) group. Patients in the DM group received oral Melatonin tablet 5 mg the night before surgery and same dose was repeated every 24 hours for 3 postoperative days. After completion of surgery and upon ICU arrival, patients in both groups received a bolus of 0.4 µg/kg dexmedetomidine followed by 0.2–0.7 µg/kg/h infusion, for 24 maximum hours. Delirium was assessed for 5 days postoperatively at 12 hr intervals using confusion assessment method (CAM) for ICU and after discharge from ICU to surgical ward using CAM. Delirious patients were treated with IV haloperidol.Results: No significant differences between studied groups regarding baseline, preoperative, intraoperative and postoperative characteristics. Incidence of delirium was significantly lower, onset significantly more delayed, and duration was significantly shorter in group-DM as compared to group-D. No significant differences between all cases, cases who had delirium, and cases who did not have delirium in the two groups as regards extubation time, ICU stay, and hospital stay.Conclusion: supplementing dexmedetomidine with melatonin decreases incidence, delays onset, and shortens duration of postoperative delirium in patients above 60 years of age undergoing CABG surgery.