Study protocol
Pediatric patients’ sex, age, weight, and size were measured and recorded by the same health care team. Their body mass index (BMI) was calculated by a monitor (GE CARESCAPE Monitor B650, Helsinki, Finland) based on their demographic variables. All of them obeyed the American Society of Anesthesiologists fasting guidelines. Intravenous access was secured with a cannula in the wards.After presenting to the operating room, the patients’ vital signs, such as heart rate (HR), pulse oxygen saturation (SpOGA was induced with 0.03~0.05 mg/kg midazolam, 2~2.5 mg/kg propofol, 0.3~0.4 μg/kg sulfentanil, followed by 0.6~1.0 mg/kg rocuronium. At the same time, facial mask preoxygenation was applied with 100% OAnesthesia was maintained in accordance with different anesthesia protocols. In the S group, patients received sevoflurane, sulfentanil and rocuronium. In the P group, propofol was used instead of sevoflurane. All of these anesthetics were discontinued at the end of the operation. During the operation, the injection speed of anesthetics and concentration of sevoflurane were regulated to keep the entropy index between 40~60, and the shift of mean arterial pressure (MAP) was maintained at less than 20% of the baseline. All patients were operated on the same surgical team with two decades of experience of CP resection.