Dexmedetomidine reduces postoperative cognitive and behavioral dysfunction in adults submitted to general anesthesia for non-cardiac surgery: meta-analysis of randomized clinical trials

INTRODUCTION AND OBJECTIVES: Dexmedetomidine (DEX) has been associated with a decrease in postoperative cognitive and behavioral dysfunction in patients submitted to general anesthesia, whether inhalation or total intravenous anesthesia. Consequently, the DEX effects on postoperative agitation and delirium in patients submitted to general anesthesia for non-cardiac surgery have been investigated. METHOD: A systematic review and meta-analysis of randomized and double-blind clinical trials (RCTs) was undertaken assessing adults submitted to elective procedures under general anesthesia receiving DEX or placebo. The search included articles published in English in the Pubmed and Web of Science databases using keywords such as dexmedetomidine, delirium, and agitation. Duplicate publications, studies involving cardiac surgery or using active control (other than saline solution) were included. A random effects model was adopted using the DerSimonian-Laird method and estimate of Odds Ratio (OR) for dichotomous variables, and weighted mean difference for continuous variables, with their respective 95% Confidence Intervals (95% CI). RESULTS: Of the 484 articles identified, 15 were selected comprising 2,183 patients (1,079 and 1,104 patients in the DEX and control group, respectively). The administration of DEX was considered a protective factor for postoperative cognitive and behavioral dysfunction (OR = 0.36; 95% CI 0.23–0.57 and p < 0.001), regardless of the anesthesia technique used. CONCLUSION: Dexmedetomidine administration reduced by at least 43% the likelihood of postoperative cognitive and behavioral dysfunction in adult patients submitted to general anesthesia for non-cardiac surgery.