Effect of Dexmedetomidine-esketamine Combined Nasal Administration on Emergence Delirium in Elderly Patients After Surgery: a Randomized, Double-blind, Placebo-controlled Trial

Emergence delirium is common in older patients after surgery and associated with worse perioperative outcomes, including increased postoperative delirium. Nasal administrations of both dexmedetomidine and esketamine are approved for medical purposes. Combination of low-dose dexmedetomidine and esketamine has shown some synergic effects in analgesia and anxiolysis. In a recent randomized trial, combined nasal administration of dexmedetomidine and esketamine was more effective in reducing pre-dental anxiety in pediatric patients. The investigators hypothesize that perioperative nasal administration of dexmedetomidine-esketamine combination can reduce the incidence of emergence delirium in older patients after surgery.