Efficacy of remimazolam with fentanyl vs midazolam with fentanyl for sedation in screening colonoscopy: Randomized controlled study

Abstract

Background and study aims

Remimazolam is a new ultra-short-acting benzodiazepine with a favorable safety-profile when used for sedation in endoscopy. The aim of this project was to investigate efficacy of remimazolam with fentanyl compared with midazolam with fentanyl for sedation in colonoscopy among fecal immunochemical test (FIT)-positive screening participants.

Patients and methods

The study was a prospective, single-blinded, randomized controlled trial. FIT-positive participants undergoing colonoscopy were randomized to intravenous remimazolam + fentanyl (RF) or midazolam + fentanyl (MF). Primary outcome was total time from start of medication until discharge. Secondary outcomes included time to reach cecum, need for post-procedure recovery, patient-reported pain and satisfaction, need for additional medication, and procedure completion.

Results

A total of 205 patients were included and randomized 1:1 (RF:103, MF:102). Mean age was 62.6 years, whereas female/male ratio was 97/108. Mean time from start of medication until discharge was 29.9 minutes (RF) versus 35.0 minutes (MF) (95% confidence interval 0.77–0.94, P = 0.012). Mean time to reach the cecum was 15.4 minutes (RF) compared with 20.2 minutes (MF) (P = 0.001). Proportion of patients requiring postoperative observation was lower for RF 0.97% vs 9.8% for MF (P = 0.022). Patients receiving remimazolam reported an average lower pain score (mean 2.25 (RF) vs 3.25 (MF) P = 0.012) and higher overall satisfaction score (4.65 vs 4.33, P = 0.012).

Conclusions

This study shows clear superiority of the combination of remimazolam with fentanyl over midazolam with fentanyl for conscious sedation in screening colonoscopy, obtaining shorter procedure time, less postoperative need for observation, lower patient pain scores, and higher patient satisfaction.

Keywords

Endoscopy Lower GI Tract - CRC screening - Colorectal cancer - Endoscopic resection (polypectomy, ESD, EMRc, ...)

Publication History

Received: 09 October 2024

Accepted after revision: 26 May 2025

Accepted Manuscript online:
14 July 2025

Article published online:
15 August 2025

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