Group 1 (PCS group, n1 = 30) used patient-controlled sedation (Propfol 1% drug, each time the patient presses the machine will inject 20mg, no refractory time set Group 2 (GM group), n2 = 30) was the usual intravenous anesthesia group (Propofol 1% dose 2mg / kg intravenous intermittent controlled by the anesthesiologist).