Patient-Controlled Sedation with Remimazolam Enables More Precise Intraoperative Sedation in Elderly Patients Under Spinal Anesthesia: A Randomized Controlled Trial

Mei Wang,1,2 Tianqi Wang,1 Nan Wu,2 Yutao Zhang,3,4 Jindi Jia,1 Shengguo Zhao,1,2 Jie Yan,1,2 Airong Wang,1 Dajiang Yuan1,5 1College of Anesthesiology, Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of China; 2Department of Anesthesiology, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of China; 3College of Second Clinical Medical, Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of China; 4Department of Orthopedics, Second Hospital of Shanxi Medical University, Taiyuan, Shanxi, People’s Republic of China; 5Department of the Party Committee, Shanxi Cardiovascular Hospital, Taiyuan, Shanxi, People’s Republic of ChinaCorrespondence: Dajiang Yuan, Department of the Party Committee, Shanxi Cardiovascular Hospital, Taiyuan, Shanxi, People’s Republic of China, Tel +86-186-3617-1219, Email yuandajiang@sina.comPurpose: To investigate whether patient-controlled sedation (PCS) with remimazolam provides more precise sedation control and superior overall outcomes compared to conventional sedation (CS) in elderly patients undergoing lower limb surgery under spinal anesthesia.Patients and Methods: 120 patients aged ≥ 65 years (ASA physical status II~III) were randomized to receive either PCS (n=60) or CS (n=60). PCS received a loading dose (1 mg), background infusion (0.75 mg·h− 1), and patient-demand boluses (0.5 mg; lockout interval 60s). CS received a loading dose (0.05~0.1 mg·kg− 1) followed by a continuous infusion (0.1~0.3 mg·kg− 1·h− 1). The primary outcome was the proportion of patients who maintained optimal sedation, defined as a Ramsay Sedation Scale score of 3~4 with supportive bispectral index (BIS) monitoring. Secondary outcomes included onset/recovery time, hemodynamics, drug consumption, adverse events, and satisfaction.Results: The proportion maintaining optimal sedation was higher in the PCS group (100% vs 88.3%, P < 0.05). PCS also showed lower total drug use, shorter recovery time (both P < 0.001), and higher scores for comfort, satisfaction, and cooperation (all P < 0.05). Hemodynamic stability was better in the PCS group, with higher mean arterial pressure at T2 through T6 timepoints (mean difference 4.5 mmHg, P = 0.019) and a lower hypotension incidence (10.0% vs 23.3%, P = 0.050).Conclusion: For elderly patients undergoing lower limb surgery under spinal anesthesia, patient-controlled sedation with remimazolam facilitates more precise sedation control. It ensures a higher proportion of optimal sedation depth while reducing drug consumption, accelerating recovery, and enhancing patient comfort and satisfaction. Under the conditions of this study, this approach constitutes a safe, effective, and individualized sedation strategy.Keywords: remimazolam, patient-controlled sedation, elderly, spinal anesthesia