Comparison of remimazolam tosylate and sevoflurane for anesthesia induction with preserved spontaneous respiration during tracheal intubation: a prospective, single-center, randomized controlled trial.

Background and objectives: Remimazolam tosylate is a novel anesthetic agent known for its rapid onset, non-irritating and non-polluting properties, effective sedation with minimal respiratory depression, short duration of action, and suitability for continuous infusion. Additionally, it can be efficiently antagonized by flumazenil. This study aims to explore the feasibility and safety of Remimazolam tosylate for anesthesia induction while maintaining spontaneous respiration.

Methods: This prospective, randomized controlled trial involved patients aged 18-65 years with non-difficult airways who were scheduled for endotracheal intubation under general anesthesia. Participants, after receiving the same protocol of dexmedetomidine sedation and Lidocaine surface anesthesia, were randomly assigned to either the sevoflurane induction group or the remimazolam tosylate induction group, with 30 patients in each group. Anesthesia induction was performed while maintaining spontaneous respiration, followed by endotracheal intubation.

Results: All enrolled patients successfully underwent intubation, and no severe respiratory depression or other complications were observed in either group (Successful anesthesia induction intubation is defined as follows: (1) successful anesthesia induction without the need for rescue measures during the induction of anesthesia, (2) no awakening during anesthesia induction, (3) spontaneous breathing is preserved throughout the entire procedure, and (4) successful completion of intubation.). There were no statistically significant differences in heart rate, blood pressure, oxygen saturation, or blood gas results between the groups. Regarding the time required for anesthesia induction, the average time to achieve the condition for topical anesthesia to the throat was 7.3 min in the remimazolam group and 17.7 min in the sevoflurane group, which was statistically significant (P < 0.01). The total time to complete intubation was 11.4 min in the remimazolam group and 21.3 min in the sevoflurane group, which was statistically significant (P < 0.01). During the local anesthetic throat spray procedure, 47% of patients in the sevoflurane group and 80% in the remimazolam group experienced coughing. This difference was statistically significant. During intubation, 20% of patients in the sevoflurane group and 33% in the remimazolam group continued to cough, but this difference was not statistically significant..

Conclusion: Compared with sevoflurane, remimazolam can be safely and effectively used for intubation while preserving spontaneous breathing, with a shorter time to achieve conditions for topical anesthesia and intubation.