Idear Narcotrend depth of anesthesia with sevoflurane for the transsphenoidal surgery for pituitary adenoma

INTERVENTION: sevoflurane deep anesthesia:Tidal volume induction with 8% sevofluran and 8 L/min O2, Remifentanil 1ug/kg.min for one min followed by 0.3ug/kg.min, Rocuronium 0.6mg/kg. Tracheal intubation was conducted when the value of TOF was 0 and the Narcotrend index (NTI) was less than 40. Anethethisa depth was kept at Narcotrend stage (NTS) E0‐E1 with sevoflurane.;sevoflurane light anesthesia:Tidal volume induction with 8% sevofluran and 8 L/min O2, Remifentanil 1ug/kg.min for one min followed by 0.3ug/kg.min, Rocuronium 0.6mg/kg. Tracheal intubation was conducted when the value of TOF was 0 and the Narcotrend index (NTI) was less than 40.Anethethisa depth was kept at Narcotrend stage (NTS) D1‐D2 with sevoflurane.; CONDITION: Nonfunctioning pituitary tumors PRIMARY OUTCOME: The lag time of extubation(the time interval between NTI was 80 and extubation);The extubation time(the time interval between withdrawing sevoflurane and extubation); SECONDARY OUTCOME: Emergence agitation (Emergence agitation was assessed by Restlessness score (RS));Postoperative sedation (It was assessed by Ramsay Sedation Score (RSS));VAS; INCLUSION CRITERIA: Patient accepted transsphenoidal surgery for non‐functional pituitary adenoma; Age 18‐65 years old; no gender limitation; ASA1‐2; weight 40‐80 kg; operation time of 1‐2 hours