A Comparison of the Safety and Efficacy of Remimazolam and Dexmedetomidine for Sedation in Surgical Patients Under Regional Anesthesia: A Meta-Analysis of Randomized Controlled Trials.

Background and Objectives: This meta-analysis compares the safety and efficacy of remimazolam and dexmedetomidine for sedation during regional anesthesia, focusing on respiratory and hemodynamic outcomes. Materials and Methods: A systematic search of CENTRAL, Embase, PubMed, Scopus, and Web of Science up to November 2024 identified randomized controlled trials (RCTs) comparing remimazolam with dexmedetomidine. Outcomes included respiratory depression (primary outcome), bradycardia, hypotension, hypertension, respiratory and heart rates, mean arterial pressure, sedation onset time, emergence time, and postoperative nausea and vomiting (PONV). Effect sizes were calculated as relative risks (RRs) or mean differences (MDs) using random-effects models. Results: Five RCTs involving 439 participants were included. Remimazolam did not significantly increase respiratory depression risk compared to dexmedetomidine (RR: 1.36, 95% CI [0.39, 4.71], p = 0.6305, I² = 44%). Bradycardia incidence was lower with remimazolam (RR: 0.15, 95% CI [0.06, 0.39], p = 0.0001, I² = 0%). Remimazolam showed faster sedation onset (MD: -6.04 min, 95% CI [-6.99, -5.09], p = 0.0000, I² = 68%). Both drugs demonstrated similar occurrences of hypotension and hypertension, respiratory rates, mean arterial pressures, emergence times, and incidences of PONV. Conclusions: Remimazolam offers comparable safety and efficacy to dexmedetomidine, with advantages such as lower bradycardia risk and faster sedation onset. These findings support remimazolam as a viable sedative option during regional anesthesia, although further large-scale studies are warranted to confirm these results and optimize sedation practices.