Impact of EEG-guided Sevofluorane on Opioid Consumption and Quality of Awakening

This prospective, randomized, single-blind, two-arm parallel-group clinical trial evaluates whether EEG-guided sevoflurane titration affects intraoperative opioid consumption and emergence quality in children undergoing painful elective surgery without regional anesthesia. Children aged 2-8 years (ASA I-II) scheduled for elective tonsillectomy (±adenoidectomy) are randomized 1:1 to a Control Group (standard 1 age-adjusted MAC; EEG screen concealed) or a Study Group (sevoflurane titrated to a stable slow-delta/alpha EEG pattern, SEF 17-20 Hz, starting at \~0.7 MAC). In both arms, fentanyl (0.5-1 mcg/kg IV) is added when nociception signs occur. The primary outcome is intraoperative fentanyl consumption (mean mcg/kg rate). Secondary outcomes include sevoflurane exposure (EtSevo, MAC-hours), EEG burst suppression, emergence time, emergence delirium (PAED scale), postoperative pain and opioid use, and hemodynamic events. Sample size: 50 participants (25/arm; 90% power, α=0.05, expected difference 2 mcg/kg, SD=2). EEG spectral analysis is performed in MATLAB using multitaper frequency-domain bootstrap. The study has institutional ethics approval; parental consent and patient assent (≥7 years) are obtained prior to enrollment.

Inclusion Criteria: * Age 2-8 years * ASA Physical Status I or II * Elective tonsillectomy (±adenoidectomy) * Signed parental consent (and assent ≥7 years) Exclusion Criteria: * Neurological or psychiatric disorders * Growth or developmental delay * Known allergy to study medications * Coagulation disorders * Parental or patient refusal