title: Evaluation of core temperature during laparoscopic and open gastric bypass.
abstract: BACKGROUND
  Intraoperative hypothermia is a common event during open and laparoscopic abdominal surgery. The aim of this study was to compare changes in core temperature between laparoscopic and open gastric bypass (GBP).
  
  
  METHODS
  101 patients with a body mass index (BMI) of 40-60 kg/m2 were randomly assigned to open (n = 50) or laparoscopic (n = 51) GBP. Anesthetic technique was similar for both groups. An external warming blanket and passive airway humidification were used intraoperatively. Core temperature was recorded at preanesthesia, at baseline (after induction) and at 30-min intervals; intra-abdominal temperature was additionally measured at 30-min intervals in a subset of 30 laparoscopic GBP patients. The number of patients who developed intraoperative and postoperative hypothermia (< 36 degrees C) was recorded. Length of operation for both groups and the amount of CO2 gas delivered during laparoscopic operations were also recorded.
  
  
  RESULTS
  There was no significant difference between groups with respect to age, gender, mean BMI, and amount of intravenous fluid administered. After induction of anesthesia, core temperature significantly decreased in both groups; 36% of patients in the open group and 37% of patients in the laparoscopic group developed hypothermia. This percentage increased to 46% in the open group and 41% in the laparoscopic group during the operation, and then decreased to 6% in the open group and 8% in the laparoscopic group in the recovery-room. Core temperature increased during the operative procedure to reach 36.5 +/- 0.6 degrees C in the open group and 36.3 +/- 0.5 degrees C in the laparoscopic group at 2.5 hours after surgical incision. Intra-abdominal temperature during laparoscopic GBP was significantly lower than core temperature at all measurement points (p < 0.05). Operative time was longer in the laparoscopic group than in the open group (232 +/- 43 vs 201 +/- 38 min, p < 0.01). Mean volume of gas delivered during laparoscopic GBP was 650 +/- 220 liters.
  
  
  CONCLUSIONS
  Perioperative hypothermia was a common event during both laparoscopic and open GBP. Despite a longer operative time, laparoscopic GBP did not increase the rate of intraoperative hypothermia when efforts were made to minimize intraoperative heat loss.
authors.affiliation: Department of Surgery, University of California, Davis, Medical Center, 2221 Stockton Blvd, 3rd Floor, Sacramento, CA 05617-1418, USA. ninh.nguyen@ucdmc.ucdavis.edu
authors.forename: N T
authors.initials: NT
authors.lastname: Nguyen
authors.forename: N W
authors.initials: NW
authors.lastname: Fleming
authors.forename: A
authors.initials: A
authors.lastname: Singh
authors.forename: S J
authors.initials: SJ
authors.lastname: Lee
authors.forename: C D
authors.initials: CD
authors.lastname: Goldman
authors.forename: B M
authors.initials: BM
authors.lastname: Wolfe
mesh_terms: D000328:Adult; D000768:Anesthesia, General / Q000009:adverse effects; D015992:Body Mass Index; D001831:Body Temperature; D005260:Female; D015390:Gastric Bypass / Q000379:methods*; D006801:Humans; D007035:Hypothermia / Q000175:diagnosis / Q000209:etiology*; D007431:Intraoperative Complications / Q000175:diagnosis; D010535:Laparoscopy / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000601:surgery