Dose optimization of remimazolam as an adjunct to propofol for gastroscopy sedation: a randomized double-blind trial

Propofol-based sedation for gastroscopy is effective but may cause dose-dependent cardiorespiratory depression; therefore, optimizing adjunct strategies to reduce propofol exposure is clinically important.

We conducted a prospective, single-center, randomized, double-blind, dose-response trial to evaluate the propofol-sparing effect of remimazolam during procedural sedation for gastroscopy. A total of 150 ASA I-II adults aged 18-59 years were randomly assigned to receive remimazolam 0, 0.05, 0.1, 0.15, or 0.2 mg·kg^-1, and propofol was titrated to achieve adequate sedation. The primary outcomes were the propofol effect-site EC50 and propofol requirement (mg·kg^-1·min^-1). Secondary outcomes included recovery profiles, post-anesthesia care unit (PACU) duration, and sedation-related adverse events.

Remimazolam reduced the propofol EC50 in a dose-dependent manner, from 3.05 (95% CI, 2.88-3.21) μg·mL^-1 at 0.05 mg·kg^-1 to 1.47 (95% CI, 1.30-1.64) μg·mL^-1 at 0.2 mg·kg^-1, and decreased propofol requirement from 0.587 ± 0.193 mg·kg^-1·min^-1 in the control group to 0.414 ± 0.121 mg·kg^-1·min^-1 at 0.1 mg·kg^-1 and 0.298 ± 0.088 mg·kg^-1·min^-1 at 0.2 mg·kg^-1. Procedure duration and PACU duration did not differ significantly among groups, and the incidence of sedation-related adverse events was comparable.

Adjunctive remimazolam provided a dose-dependent propofol-sparing effect during gastroscopy sedation. Among the tested doses, 0.1 mg·kg^-1 appeared to offer a favorable balance between reduced propofol requirement and recovery profile, supporting its clinical feasibility under the conditions studied.

Chinese Clinical Trial Registry, identifier ChiCTR2400094449.