What question did this study set out to answer?

This research aims to clarify how remimazolam dosage and bolus injection rate affect hiccup occurrence during painless colonoscopy.

May 20, 2026Open Access

Effects of Remimazolam Dose and Bolus Injection Rate on Hiccups During Painless Colonoscopy: A Double-Blind Randomized Clinical Trial

Key Points

This research aims to clarify how remimazolam dosage and bolus injection rate affect hiccup occurrence during painless colonoscopy.
Prospective randomized double-blind 2×2 factorial trial
Adult patients receiving remimazolam at 0.3 or 0.4 mg kg − 1 over 10s or 20s
Primary endpoint was hiccup incidence, with multiple secondary endpoints assessed.
0.4 mg kg − 1 dose associated with lower hiccup odds compared to 0.3 mg kg − 1 (HR not specified)
20s injection rate lowered hiccup incidence compared to 10s (HR not specified)
Higher-dose regimen also linked to fewer body movements without increased haemodynamic issues.

Abstract

Background: Remimazolam is increasingly used for procedural sedation because of its rapid onset, rapid recovery and favourable haemodynamic profile. However, hiccups remain a clinically relevant adverse event that may interfere with endoscopic manipulation. The independent and combined effects of remimazolam dose and injection rate on hiccup occurrence have not been well characterized. Methods: In this prospective, randomized, double-blind, 2× 2 factorial trial, adult patients undergoing painless colonoscopy were randomized to receive remimazolam at 0.3 or 0.4 mg kg − 1 , administered over 10s or 20s. The primary endpoint was hiccup incidence. Secondary endpoints included body movement, supplemental bolus requirements, time to loss of eyelash reflex, recovery time, haemodynamic changes, Modified Observer’s Assessment of Alertness/Sedation (MOAA/S) scores and postoperative Numeric Rating Scale (NRS) scores. Multivariable logistic regression evaluated the independent effects of dose and injection rate on hiccup incidence and tested for interaction. Results: Both the higher remimazolam dose (0.4 mg kg − 1 ) and the slower bolus injection rate (20s) were independently associated with a lower incidence of hiccups. After adjustment for age, sex, body mass index, smoking status, hypertension and diabetes, the 0.4 mg kg − 1 regimen showed lower odds of hiccups than the 0.3 mg kg − 1 regimen, and 20s administration showed lower odds than 10s. No significant dose × rate interaction was detected. The higher-dose regimen was additionally associated with fewer body movements and supplemental boluses, without increased haemodynamic compromise. Conclusion: Both a higher remimazolam dose and a slower bolus injection rate were independently associated with a lower incidence of hiccups during painless colonoscopy. Remimazolam 0.4 mg kg − 1 administered over 20s may offer the most favourable balance between hiccup prevention, procedural conditions and haemodynamic stability. Keywords: remimazolam, hiccups, colonoscopy, injection rate, factorial trial

Bookmark

View Full Paper