Objective:Drug-induced sleep endoscopy(DISE)allows for the evaluation of dynamic airway collapse in patients with obstructive sleep apnea.However,a standardized sedation regimen for DISE is not yet available.This study aimed to investigate the safety profiles and efficacies of dexmedetomidine combined with butorphanol for DISE.Methods:Sixty patients with obstructive sleep apnea scheduled to undergo DISE were randomly divided into Group D and Group DB.All recipients were initially given intravenous butorphanol(1 mg)(Group DB)or saline(Group D).Subsequently,both groups were sedated using a loading dose of 1.0 μg/kg/h of dexmedetomidine.Hemodynamic and respiratory parameters,the time to attain sufficient sedation,wakeup time,and adverse events during DISE were recorded.Results:Compared with Group D,the time until sufficient sedation and wakeup time in Group DB were significantly reduced.A higher performer satisfaction level was achieved in Group DB.Patients in Group DB showed a higher incidence of bradycardia compared with Group D.However,the bradycardia resolved spontaneously in both groups without any treatment.There was no instance of cough,hypotension,arrhythmia,nausea or vomiting in either group.Conclusion:Compared to dexmedetomidine alone,a small dose of butorphanol infusion(1 mg)as an adjunct treatment to dexmedetomidine during DISE can reduce the dosage of dexmedetomidine,shorten the time until sufficient sedation and enhance the performer satisfaction level.This synergistic combination could be a promising sedation regimen for DISE in terms of procedural convenience and patient safety.