Effects of Perioperative Dexmedetomidine on Postoperative Mortality and Morbidity: A Systematic Review and Meta-analysis.

PURPOSE: Major postoperative complications translate into increased health care resource utilization, prolonged hospital stays, and increased mortality. We aimed to assess the effects of perioperative dexmedetomidine use on postoperative mortality and the prevalence of major complications after cardiac and noncardiac surgery.

METHODS: We searched the PubMed, EMBASE, and Cochrane databases to analyze all published evidence from randomized controlled trials (RCTs) and cohort studies comparing perioperative dexmedetomidine use versus no dexmedetomidine use in adult patients undergoing cardiac and noncardiac surgery. The primary outcome was postoperative mortality. Secondary outcomes were the durations of mechanical ventilation, intensive care unit (ICU) stay, and hospital stay, and the prevalence of major complications.

FINDINGS: Twenty-three studies in cardiac surgery (n = 7635) and 8 studies in noncardiac surgery (n = 1805) were included. In cardiac surgery, dexmedetomidine use reduced postoperative 30-day mortality (risk ratio [RR], 0.35 [95% CI, 0.24 to 0.51]); durations of mechanical ventilation (mean difference [MD], -1.56 h [-2.52 to -0.60]), ICU stay (MD, -0.22 day [-0.35 to -0.08]), and hospital stay (MD, -0.65 day [-1.12 to -0.18]); and the prevalences of delirium (RR, 0.50 [0.36 to 0.69]), atrial fibrillation (RR, 0.74 [0.57 to 0.97]), and cardiac arrest (RR, 0.34 [0.13 to 0.87]). In noncardiac surgery, dexmedetomidine use was associated with decreases in the durations of mechanical ventilation and hospital stay, with a trend toward a lower prevalence of delirium (RR, 0.57 [0.32 to 1.01]). The prevalence of bradycardia was increased in dexmedetomidine-treated patients undergoing cardiac surgery (RR, 1.70 [1.19 to 2.44]) and noncardiac surgery (RR, 1.64 [1.05 to 2.58]).

IMPLICATIONS: Dexmedetomidine use may help to reduce postoperative 30-day mortality, durations of mechanical ventilation, ICU stay, and hospital stay, and the prevalences of delirium, atrial fibrillation, and cardiac arrest in patients who undergo cardiac surgery. The majority of the benefits of dexmedetomidine were not significant in patients undergoing noncardiac surgery. An increased risk for bradycardia should be taken into consideration when prescribing dexmedetomidine. International Prospective Register of Systematic Reviews identifier: CRD42017070791.