Efficacy of Dexmedetomidine in Preventing Postoperative Delirium in Patients Undergoing Brain Surgery: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Dexmedetomidine (DEX), a selective alpha-2 adrenergic receptor agonist, is widely used in various surgical settings, including cardiac and general surgeries, for its sedative, analgesic, and neuroprotective properties. Patients undergoing brain surgery are particularly susceptible to postoperative delirium (POD). Given the established benefits of dexmedetomidine in other surgical fields, its potential to mitigate delirium in neurosurgery warrants investigation.

METHODS: A systematic search of PubMed, Embase, Scopus, and Cochrane databases was conducted from inception to January 2025 and updated in April 2025, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Risk of bias was assessed, and a meta-analysis was performed using Review Manager 5.4.1. Five randomized controlled trials were included, evaluating the efficacy of DEX in preventing POD in adult patients undergoing brain surgery.

RESULTS: A total of 646 patients were enrolled, with DEX administered with a loading dose ranging from 0.5 to 1 μg/kg over 10 min, followed by a maintenance infusion rate of 0.1 to 0.5 μg/kg/h during the surgical procedure. The pooled risk ratio (RR) for POD with DEX was 0.47 (95% confidence interval (CI): 0.35-0.63; p < 0.00001); reflecting a 53% reduction in the risk of postoperative delirium, with no statistical heterogeneity detected (χ2 = 2.09, degrees of freedom (df) = 4, p = 0.72; I2 = 0%). Subgroup analyses showed similar effect estimates across brain tumor and other cranial procedures. Adverse events were comparable between groups and generally mild.

CONCLUSIONS: This meta-analysis found that perioperative dexmedetomidine was associated with a significant reduction in postoperative delirium risk in neurosurgical patients. Further multicenter trials are needed to confirm these findings and to refine optimal administration strategies.