Effect of dexmedetomidine on postoperative mortality and prognosis: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVE

This meta-analysis aimed to systematically evaluate the impact of intraoperative dexmedetomidine (DEX) on postoperative mortality and clinical outcomes in surgical patients, addressing existing controversies in the literature.

METHODS

We conducted a systematic review of randomized controlled trials (RCTs) from PubMed, Embase and Cochrane Library (inception to October 8, 2024; PROSPERO: CRD42024583524). Included studies compared intraoperative DEX against controls (placebo/active comparators) in adults undergoing general anesthesia. Primary outcome was mortality; secondary outcomes included postoperative delirium (POD), ICU/hospital stay, mechanical ventilation duration, and safety endpoints. Risk ratios (RR) or mean differences (MD) with 95% confidence intervals (CI) were pooled using fixed/random-effects models.

RESULTS

This meta-analysis included 17 randomized controlled trials (RCTs). In cardiac surgery patients, DEX significantly reduced all-cause mortality (RR 0.39, 95% CI 0.18-0.85; P = 0.02) and in-hospital mortality (RR 0.23, 95% CI 0.08-0.70; P = 0.01), but not 30-day mortality. In non-cardiac surgery patients, DEX did not significantly reduce all-cause, 30-day, or in-hospital mortality. DEX decreased the incidence of POD in both cardiac (RR 0.61, 95% CI 0.46-0.82; P = 0.001) and non-cardiac surgery patients (RR 0.56, 95% CI 0.36-0.87; P = 0.01). For other outcomes, significant reductions in hospital stay, ICU stay, and mechanical ventilation duration were primarily observed in the cardiac surgery subgroup. Safety analysis indicated there was no significant difference in intraoperative bradycardia or hypotension between groups.

CONCLUSIONS

Dexmedetomidine use in cardiac surgery significantly reduces all-cause and in-hospital mortality, shortens hospital length of stay, decreases ICU stay duration, and reduces mechanical ventilation requirements. However, its impact on 30-day mortality is not significant. Additionally, the drug consistently demonstrates a preventive effect on postoperative delirium across different surgical types.Clinicians must carefully weigh the benefits of this medication against the potential risk of transient hemodynamic instability.