title: Effect of different depths of anesthesia on postoperative cognitive function in laparoscopic patients: a randomized clinical trial.
abstract: OBJECTIVE
  Postoperative cognitive dysfunction (POCD) is caused by many factors. This work was conducted to investigate the effect of different depths of anesthesia during combined intravenous-inhalational anesthesia on postoperative cognitive function in young and middle-aged laparoscopic patients.
  
  
  METHODS
  A total of 192 patients scheduled for gynecologic laparoscopic operations were randomly divided into three groups. Anesthesia was maintained with inhalation of sevoflurane and infusion of remifentanil, which was adjusted to maintain bispectral index (BIS) at 30 < BIS ≤ 40 in Group I, 40 < BIS ≤ 50 in Group II and 50 < BIS ≤ 60 in Group III. The Mini-Mental State Examination (MMSE) and Trail-Making Test (TMT) were used to assess cognitive function on the day before anesthesia and the day after surgery.
  
  
  RESULTS
  There were no significant differences in age, body mass index, educational level and surgery time. On the day before anesthesia, the average MMSE scores and TMT completion times in the three groups were not significantly different. On the day after surgery, Group II had a significantly higher average MMSE score (29.00 ± 0.89) than Group I (28.36 ± 1.42, p = 0.010) and Group III (28.45 ± 1.27, p = 0.035) and lower TMT completion time (33.68 ± 10.34) than Group I (39.45 ± 13.99, p = 0.027) and Group III (39.50 ± 12.50, p = 0.026).
  
  
  CONCLUSIONS
  These results indicated that the depth of anesthesia, 40 < BIS ≤ 50, under combined intravenous-inhalational anesthesia yielded milder influence on postoperative cognitive function in young and middle-aged laparoscopic patients.
authors.affiliation: a Department of Anesthesiology , Three Gorges University People's Hospital, the First People's Hospital of Yichang , Yichang , Hubei , China.
authors.forename: Ai-Hua
authors.initials: AH
authors.lastname: Shu
authors.affiliation: a Department of Anesthesiology , Three Gorges University People's Hospital, the First People's Hospital of Yichang , Yichang , Hubei , China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Wang
authors.affiliation: a Department of Anesthesiology , Three Gorges University People's Hospital, the First People's Hospital of Yichang , Yichang , Hubei , China.
authors.forename: Xiao-Bo
authors.initials: XB
authors.lastname: Chen
mesh_terms: D000328:Adult; D000758:Anesthesia / Q000379:methods; D018685:Anesthetics, Inhalation / Q000008:administration & dosage*; D003071:Cognition / Q000187:drug effects; D004311:Double-Blind Method; D005260:Female; D013509:Gynecologic Surgical Procedures / Q000379:methods; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008738:Methyl Ethers / Q000008:administration & dosage*; D008875:Middle Aged; D009483:Neuropsychological Tests; D010880:Piperidines / Q000008:administration & dosage*; D011183:Postoperative Complications / Q000453:epidemiology; D011184:Postoperative Period; D000077208:Remifentanil; D000077149:Sevoflurane; D055815:Young Adult
chemical_list: D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D010880:Piperidines; D000077149:Sevoflurane; D000077208:Remifentanil
keywords: Bispectral index; Laparoscopic operation; Postoperative cognitive dysfunction; Remifentanil; Sevoflurane