RESUMO
OBJECTIVE: Conflicting data exist on the effect of dexmedetomidine on delirium. For the present study, a randomized trial was performed to investigate the effect of perioperative dexmedetomidine on the rate of postoperative delirium after cardiac surgery. DESIGN: A randomized controlled trial. SETTING: University hospital. PARTICIPANTS: Patients (nâ¯=â¯169) undergoing elective cardiac surgery (coronary artery bypass graft surgery, valve surgery, or combined surgery) with cardiopulmonary bypass. INTERVENTIONS: Patients received a sevoflurane-based general anesthesia and were randomly assigned 1:1 to receive a dexmedetomidine infusion that started in the operating room (0.7 µg/kg/h) and continued into the intensive care unit (0.4 µg/kg/h) or an equivolume infusion of placebo. MEASUREMENTS AND MAIN RESULTS: A decrease in the rate of delirium in the dexmedetomidine group compared with the placebo group was demonstrated (6 of 84 [7.1%] v 16 of 85 [18.8%]; pâ¯=â¯0.02; odds ratio [OR] 0.33 [95% confidence interval {CI} 0.12-0.90]). Reduced intensive care unit and hospital lengths of stay also were observed (18 [18-22] hours v 22 [18-39] hours; pâ¯=â¯0.002 and 17 [7-20] days v 19 [8-21] days; pâ¯=â¯0.04, respectively). Mortality at 30 days was 2 (2.4%) in both groups. On multivariate analysis, only dexmedetomidine administration (OR 0.24 [95% CI 0.08-0.74]) and cardiopulmonary bypass time (OR 1.02 [95% CI 1.01-1.03] for increases of 1 min) were independent predictors of delirium development. CONCLUSIONS: Dexmedetomidine administered during and after general anesthesia for cardiac surgery with cardiopulmonary bypass decreased the rate of postoperative delirium and intensive care unit and hospital lengths of stay.