Abstract
PURPOSE: This study evaluated whether intranasal esketamine premedication reduces sevoflurane requirements for laryngeal mask airway (LMA) insertion in young children. PATIENTS AND METHODS: This randomized, double-blind, placebo-controlled trial enrolled 90 children (2-5 years) undergoing elective strabismus surgery. Participants received intranasal premedication with either saline (control), esketamine 0.5 mg/kg, or esketamine 1.0 mg/kg. The primary outcome was the minimum alveolar concentration of sevoflurane needed for successful LMA placement, determined using Dixon's up-and-down method. Secondary outcomes included anesthesia induction quality (4-point cooperation scale), emergence delirium (Pediatric Anesthesia Emergence Delirium scale), emergence time (from sevoflurane discontinuation to purposeful response), behavioral changes at day 3 (Post-Hospitalization Behavior Questionnaire), and adverse events. RESULTS: Intranasal esketamine produced dose-dependent reductions in sevoflurane requirements: 2.16 ± 0.18% (control), 1.87 ± 0.17% (0.5 mg/kg), and 1.50 ± 0.19% (1.0 mg/kg), representing decreases of 13.4% and 30.6%, respectively. The higher esketamine dose significantly improved induction quality (p=0.002), reduced emergence delirium (13.8% versus 46.4%, p=0.007), and decreased negative postoperative behavioral changes on day 3 (20.7% versus 53.6%, p=0.010). Emergence time and adverse event rates remained similar across groups. CONCLUSION: Intranasal esketamine premedication effectively reduces sevoflurane requirements for LMA placement in children in a dose-dependent manner. The 1.0 mg/kg dose provides optimal clinical benefits without prolonging recovery or increasing complications. This approach offers pediatric anesthesiologists a practical method to reduce volatile anesthetic exposure while improving patient outcomes and potentially minimizing anesthetic-related risks.