Efficacy and Safety of Remimazolam versus Dexmedetomidine and Midazolam in Awake Endotracheal Intubation for Difficult Airway Patients: A Randomized Controlled Study.

OBJECTIVE

To compare the safety and efficacy of remimazolam, dexmedetomidine, and midazolam in awake endotracheal intubation by flexible bronchoscopy for patients with difficult airways.

METHODS

Ninety patients with difficult airways undergoing elective surgical procedures requiring awake endotracheal intubation under general anesthesia were randomly assigned to three groups, with 30 patients per group: Group M (midazolam), which received a 0.04 mg/kg intravenous (IV) bolus; Group D (dexmedetomidine), which was given via intravenous infusion pump at a rate of 1.0 µg/kg/min for 10 minutes; and Group R (remimazolam), which received a 0.15 mg/kg IV bolus. All patients first received 0.1μg/kg of sufentanil intravenously for basic analgesia. A 2-minute interval was allowed to ensure initial onset of the analgesic effect, followed by administration of the respective sedative agents for each group as detailed above. Upon achieving a Modified Observer's Assessment of Alertness/Sedation (MOAA/S) score of≤2, pharyngeal topical anesthesia was administered, followed by flexible fiberoptic endotracheal intubation. The primary outcome measure was the first-attempt intubation success rate. All other evaluated parameters were defined as secondary outcomes. Mean arterial pressure (MAP), heart rate (HR), and oxygen saturation (SpO2) were recorded at four time points: baseline (T0), immediately before intubation (T1), immediately after intubation (T2), and 3 minutes post-intubation (T3). Additional outcomes assessed included the duration of anesthetic induction, the interval from induction to intubation, patient comfort levels, post-induction MOAA/S scores, and the incidence of adverse events.

RESULTS

The first-attempt intubation success rates across the three groups were 70%, 93.3%, and 100%, respectively. Compared with the values at T1, mean arterial pressure (MAP) and heart rate (HR) were significantly higher in Group M at T2 and T3 (both P<0.05). In Group D, HR at T1 was significantly lower than that at T0 (P<0.05). For inter-group comparisons, HR in Group D was significantly lower than in Group R at T1 (P<0.05). Additionally, Group D had the longest duration of anesthetic induction and the longest interval from induction to intubation (both P<0.05). Compared with Group M, both Group D and Group R exhibited significantly higher first-attempt intubation success rates (P<0.05). Group R achieved the highest patient comfort scores, the highest success rate of sedation after a single induction dose, and the lowest incidence of adverse events (all P<0.05).

CONCLUSION

Remimazolam provides effective sedation for awake tracheal intubation in patients with difficult airways. It exerts minimal impact on respiratory and circulatory function, is associated with fewer adverse events, and yields a higher intubation success rate, making it a favorable option for this patient population.