After 3 minutes of 100% pre-oxygenation, general anesthesia will be induced by Sevoflurane inhalation 4-6% MAC via facemask then intravenous line will be secured and intravenous fluids (NaCl 0.9%) will be started at the calculated volume and rate. Fentanyl 1 µg/kg and Propofol 1.5 mg/kg will be given intravenously then intubation with oral RAE tube of the appropriate size will be inserted and secured. Assisted ventilation will be adjusted to maintain 30-35 mmHg EtCO2. Anesthesia will be maintained with 100% O2 and Sevoflurane 2-4% MAC. Broad spectrum antibiotic will be given to each child participated in the study.