Efficacy and Safety of Remimazolam Compared to Midazolam for Sedation During Endoscopic Ultrasonography: A Single-Center Retrospective Cohort Study.

OBJECTIVES

Remimazolam is a novel ultra-short-acting benzodiazepine that may offer advantages over conventional sedatives in endoscopic procedures. Evidence for its use in pancreatobiliary endoscopic ultrasonography (EUS) is limited. We compared the efficacy and safety of remimazolam and midazolam in outpatient pancreatobiliary EUS.

METHODS

This retrospective study included outpatients undergoing diagnostic pancreatobiliary EUS between July 2024 and July 2025. Patients received either remimazolam (initial 0.2 mg/kg, top-up 0.1 mg/kg [high-risk patients: 0.16 mg/kg, 0.08 mg/kg]) or midazolam. The target sedation depth was Modified Observer's Assessment of Alertness/Sedation ≤3, procedures were performed without supplemental oxygen, and pentazocine was co-administered. The primary outcome was rapid recovery (meeting all criteria: modified Aldrete score ≥6 at 5 min, ≥9 at 30 min, ambulation ≥3 m at 30 min). Secondary outcomes included sedation success (all: EUS completion, without >2 top-ups within 10 min, without rescue sedation, without agitation requiring interruption), recovery time, flumazenil use, and adverse events.

RESULTS

We analyzed 139 patients (remimazolam, n = 75; midazolam, n = 64). Rapid recovery was more frequent with remimazolam (70.7% vs. 25.0%, p < 0.001). Sedation success was higher (92.0% vs. 73.4%, p = 0.005), recovery was shorter (median 34 vs. 55 min, p < 0.001), and flumazenil use was lower (4.0% vs. 45.3%, p < 0.001). Hypoxemia (SpO2 <90% lasting ≥10 s) occurred slightly more often with remimazolam (30.6% vs. 26.6%, p = 0.707), but all episodes were mild and reversible with airway support/oxygen. Hypotension was rare and comparable.

CONCLUSIONS

Remimazolam provided faster recovery and higher sedation success than midazolam in outpatient pancreatobiliary EUS. Supplemental oxygen before sedation is a reasonable option to enhance safety.