Efficacy of Different Doses of Remimazolam Tosilate Combined with Esketamine in Painless Abortion Patients: A Prospective, Double-Blind, Randomized Controlled Trial.

Background: Remimazolam tosilate (RT) is a novel ultra-short-acting benzodiazepine with rapid onset, short half-life, stable hemodynamics, and minimal respiratory depression. This study aimed to assess the efficacy, safety, and optimal dosage of RT combined with esketamine for painless abortion procedures. Methods: This single-center, prospective, randomized, double-blind trial was conducted from December 2022 to December 2024. A total of 210 patients (aged 18-45 years, ASA I-II, BMI 18-28 kg/m2) undergoing elective painless abortion were randomly assigned to one of three groups: propofol 2 mg/kg (Group P), RT 0.2 mg/kg (Group RL), or RT 0.3 mg/kg (Group RH). Primary outcomes were perioperative hemodynamic changes, assessed by mean arterial pressure fluctuation value (ΔMAP) and heart rate fluctuation value (ΔHR). Secondary outcomes included adverse events, vital sign changes, induction and recovery times, surgical duration, time to discharge readiness, need for additional sedation, visual analogue scale (VAS) pain scores at awakening and discharge, and satisfaction levels of patients, surgeons, and anesthesiologists. Results: The ΔMAP in Group RL (7.11 ± 2.49) was significantly lower than in Group P (11.93 ± 2.09) and Group RH (12.80 ± 2.59) (F = 114.286, P < 0.001), indicating more stable perioperative hemodynamics. Group RL also showed shorter recovery time and quicker discharge readiness. Hypotension incidence was lower in Groups P and RL compared to RH. Rates of hypoxemia, nausea/vomiting, and neuropsychiatric symptoms were significantly lower in Groups RL and RH than in Group P. RT required fewer supplemental doses than propofol, and patient satisfaction was highest in Group RL. No significant differences were observed among groups for ΔHR, induction time, surgical duration, hypertension, body movement, injection pain, postoperative pain, or patient/surgeon/anesthesiologist satisfaction. Conclusion: Low-dose RT (0.2 mg/kg) combined with esketamine significantly shortens recovery and discharge times, ensures hemodynamic stability, and reduces adverse events, making it the recommended sedation strategy for painless abortion procedures.