Remimazolam is a novel, short-acting benzodiazepine with organ-independent metabolism, offering rapid onset and fast recovery, making it well-suited for outpatient procedures. Its pharmacokinetic properties also make it an attractive candidate for patient-controlled sedation (PCS), enabling patients to self-titrate sedation within predefined limits for optimized, individualized dosing (Davodi J, et al. Journal of Patient Safety and Risk Management 2025). In this proof-of-concept study, we aimed to evaluate, for the first time, the feasibility, safety, and patient satisfaction of PCS with remimazolam during outpatient colonoscopy.

Ten randomly selected patients (median age 61 years, range 53–71; 50% female) scheduled for outpatient colonoscopy were enrolled. Indications included colorectal cancer screening due to positive fecal occult blood test (n=7), inflammatory bowel disease surveillance (n=2), and adenoma surveillance (n=1). PCS was delivered via an infusion pump (CADD-Solis, ICU Medical, San Clemente, USA), with an initial bolus of 5–7.5 mg remimazolam combined with 1 mg of alfentanil, followed by patient-activated 2.5 mg boluses with a 2-minute lockout period. Vital signs (oxygen saturation, heart rate, respiratory rate, and non-invasive blood pressure) were continuously monitored. Any adverse events were classified according to the international reporting tool on adverse events in sedation. Patient satisfaction was assessed post-procedure using a validated 5-point Likert scale.

All ten colonoscopies were completed successfully. The median number of remimazolam boluses was 3.5 (range 0–7), corresponding to a median total dose of 14.0 mg (range 5.0–27.5 mg). The median procedure duration was 41 minutes (range 23–105). The safety profile of remimazolam was favorable, and no serious adverse events occurred. Only minimal adverse events were observed in three patients (30%), consisting of brief and transient oxygen desaturation, which resolved spontaneously. No clinically relevant effects on hemodynamic parameters were noted throughout the procedures, and no patients required airway support or reversal agents. One patient was transferred to the recovery room as a precaution due to subcutaneous infiltration at the infusion site; all others were discharged directly from the endoscopy room.

Overall patient satisfaction was high across all participants. All participants reported high or very high satisfaction with the sedation quality (median 5.0), pain relief (median 5.0), and anxiety reduction (median 5.0). Notably, all patients expressed high satisfaction with the ability to control their sedation levels, which is reflected in some patients opting to use fewer or no boluses than others. Satisfaction also appeared to be higher than what we have previously observed with nurse-administered propofol sedation (NAPS) in our earlier study, which used identical questionaries (Steenholdt C, et al. Clinical Gastroenterology and Hepatology 2022; 559-568). Feedback from the endoscopists indicated that the sedation regimen provided satisfactory working conditions without compromising procedural quality.

This pilot experience also highlighted inter-patient variability in sedation needs. Some patients required few boluses, while others required more frequent dosing, suggesting that a standardized protocol may not fit all. Factors such as anxiety level, frailty, previous procedural experience, or body weight may influence sedation demand, emphasizing the adaptability of PCS to individual needs.

PCS with remimazolam is a feasible, safe, and well-tolerated option for outpatient colonoscopy. The setup is straightforward, and the built-in lockout mechanism provides an inherent safety feature that helps prevent over-sedation. An antidote is also available if needed. This approach may reduce staff workload by allowing nurses to focus more on procedural assistance rather than manually titrating sedatives. Unlike propofol, which is generally contraindicated in high ASA patients, PCS with remimazolam may be a promising option for frail individuals or patients who prefer to remain partially conscious during the procedure. Our proof-of-concept observations support the rationale for controlled trials to evaluate PCS with remimazolam as a potential alternative to current standards in endoscopic sedation.