Preoperative oral dextromethorphan does not reduce pain or analgesic consumption in children after adenotonsillectomy

In this randomized, double-blinded, placebo-controlled, prospective study, we evaluated the analgesic efficacy of dextromethorphan 0.5 mg/kg or 1.0 mg /kg PO 1 h before adenotonsillectomy in 57 children 6-12 yr of age. Anesthe tic management was standardized. Morphine 0.075 mg/kg IV and acetaminophen 25-35 mg/kg PR were administered after anesthetic induction but before the start of surgery. A 4-point behavioral score (1 = asleep, 2 = awake and cal m, 3 = awake and crying, 4 = thrashing) was recorded on admission to and di scharge from the postanesthesia care unit (PACU). In the PACU, pain was ass essed with Children's Hospital of Eastern Ontario Pain Scale (CHEOPS) and r ecorded every 15 min until the patient was transferred to the day surgery u nit (DSU). In the DSU, patients rated their pain using a 10-cm baseline 0-1 0 visual analog pain scale (VAS) every 30 min until they were discharged ho me. A 24-h VAS was obtained by phone interview, and parental satisfaction w as scored (yes/no) regarding their child's postoperative analgesia. Morphin e 0.025 mg/kg TV was administered to children with CHEOPS score >6, who ver balized pain, or who were crying in any consecutive 5-min observation perio ds in the PACU. Total morphine consumption was recorded. The study groups w ere comparable with respect to demographic variables. We were unable to det ect any differences between study groups with respect to postoperative morp hine consumption, CHEOPS, behavior scores, VAS, or parental satisfaction. I mplications: Premedication with dextromethorphan 0.5 or 1.0 mg/kg PO does n ot improve postoperative analgesia in school-aged children who receive pree mptive morphine 0.075 mg/kg IV and acetaminophen 25-35 mg/kg PR during nitr ous oxide and desflurane anesthesia for adenotonsillectomy.