Comparing Cognitive Recovery of Remimazolam versus Propofol in Elderly Patients Undergoing Colonoscopy: A Randomized Controlled Trial.

Background: Remimazolam, a novel ultra-short-acting benzodiazepine, shows promise for procedural sedation. This study compared the cognitive recovery of remimazolam versus propofol in elderly patients undergoing colonoscopy. Patients and Methods: In this prospective, randomized, double-blind, controlled trial, 228 patients aged ≥ 65 years undergoing outpatient colonoscopies were recruited. Patients received intravenous sufentanil 0.05 μg/kg, followed by either remimazolam 0.2 mg/kg or propofol 1 mg/kg for sedation induction. The assigned study drug (remimazolam 0.1 mg/kg or propofol 0.5 mg/kg) was titrated to maintain a Modified Observer's Assessment of Alertness/Sedation scale score < 3 during the procedure. The primary outcome was the incidence of cognitive recovery, assessed using the Postoperative Quality of Recovery Scale (PostopQRS) cognitive domain on postoperative day 3. Secondary outcomes included overall and other PostopQRS domains recovery, time to discharge, patient satisfaction, and adverse events. Results: Cognitive recovery on day 3 was similar between remimazolam (84.2%) and propofol (85.1%) groups (risk ratio = 0.99; 95% CI: 0.89-1.11; p = 0.854). No significant differences were observed in overall recovery, other domains, or discharge time. Remimazolam patients reported higher satisfaction (p = 0.001) and experienced lower incidences of hypotension (21.9% vs 53.5%; p < 0.001), hypoxemia (6.1% vs 16.7%; p = 0.024), and injection site pain (15.8% vs 41.2%; p < 0.001) compared to propofol. Conclusion: In elderly patients undergoing colonoscopy, remimazolam demonstrated comparable cognitive recovery to propofol, with higher patient satisfaction and a more favorable safety profile. Remimazolam may be the preferred alternative to propofol for procedural sedation in this vulnerable population. Trial Registration: The Chinese Clinical Trial Registry, ChiCTR2200066689.