Effects of remimazolam on postoperative delirium in adults undergoing general anesthesia: a systematic review and meta-analysis

Benzodiazepines have traditionally been associated with postoperative delirium (POD), but the effect of remimazolam on POD remains uncertain. This systematic review and meta-analysis evaluated the incidence of POD and perioperative safety outcomes associated with remimazolam in adults undergoing general anesthesia. We searched databases from inception through April 27, 2025, and included randomized controlled trials and non-randomized studies comparing remimazolam with conventional anesthetic agents in adults undergoing general anesthesia. The primary outcome was POD incidence, and secondary outcomes comprised perioperative safety measures. We assessed the certainty of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. Seventeen studies involving 3,180 patients were included. POD incidence did not differ significantly between the remimazolam and control groups (risk ratio [RR], 0.88; 95% confidence interval [CI], 0.71–1.09; I2 = 0%). Similarly, the incidence of intraoperative hypotension did not differ significantly between groups (RR, 0.77; 95% CI, 0.56–1.06). Remimazolam was associated with lower incidences of vasopressor administration (RR, 0.62; 95% CI, 0.41–0.93) and bradycardia (RR, 0.78; 95% CI, 0.62–0.99). Time to eye opening and the incidence of postoperative nausea and vomiting did not differ significantly between groups. The certainty of evidence was very low for POD and low or moderate for secondary outcomes. POD incidence did not differ significantly between remimazolam and conventional anesthetic agents in adults undergoing general anesthesia. Some secondary outcomes suggested a potentially favorable hemodynamic profile; however, the evidence was limited and heterogeneous. Further trials using standardized POD assessment tools and prespecified hemodynamic endpoints are warranted.