Anesthesia regimen After establishing routine invasive arterial blood pressure and noninvasive patient monitoring such as pulse oximetry (SpO2), electrocardiography, bispectral index (BIS) and cerebral oximetry, anesthesia is induced by two staff anesthesiologist (AA and BB) using a target controlled infusion (TCI) of propofol (effect site concentration, Ce, of 2.0 µg/ml) and remifentanil (plasma concentration, Cp, of 20 ng/ml with the time to reach target concentration of 7 min) in Group R (by AA), and anesthesia is induced by bolus injection of thiopental sodium 3-4 mg/kg and maintained using TCI- sufentanil (Cp of 0.4 ng/ml) in Group C (by BB). Muscle relaxation and tracheal intubation is facilitated by bolus rocuronium under the guidance of peripheral neuromuscular transmission.