title: Nitrous oxide and laparoscopic bariatric surgery.
abstract: BACKGROUND
  Nitrous oxide (N2O) is frequently used to supplement more potent anesthetic agents. One side-effect of N2O is its ability to expand an air-containing space. We investigated if N2O adversely affected operating conditions by distending normal bowel during laparoscopic bariatric procedures.
  
  
  METHODS
  50 morbidly obese patients were divided into 2 study groups. Group 1 patients were ventilated with a halogenated anesthetic/oxygen/air mixture, while Group 2 received a halogenated anesthetic/oxygen/N2O mixture. At 30, 60, and 90 min intervals during the operation, the surgeon was asked if N2O was being used.
  
  
  RESULTS
  The surgeons responded correctly only 42% (30 min), 50% (60 min), and 48% (90 min) of the time. In Group 2 (N2O) patients, they incorrectly answered that N2O was not being used 88% (30 min), 68% (60 min), and 68% (90 min); and in Group 1 (air) patients, they incorrectly answered that N2O was being used 28% (30 min), 32% (60 min), and 36% (90 min) of the time.
  
  
  CONCLUSIONS
  We found that using N2O did not cause noticeable bowel distention during laparoscopic bariatric procedures of relatively short duration.
authors.affiliation: Department of Anesthesia, Stanford University School of Medicine, Stanford, CA 94305, USA. Jbrodsky@stanford.edu
authors.forename: J B
authors.initials: JB
authors.lastname: Brodsky
authors.forename: H J M
authors.initials: HJ
authors.lastname: Lemmens
authors.forename: J S
authors.initials: JS
authors.lastname: Collins
authors.forename: J M
authors.initials: JM
authors.lastname: Morton
authors.forename: M J
authors.initials: MJ
authors.lastname: Curet
authors.forename: J G
authors.initials: JG
authors.lastname: Brock-Utne
mesh_terms: D000328:Adult; D000762:Anesthesia Recovery Period; D000769:Anesthesia, Inhalation; D018685:Anesthetics, Inhalation; D015992:Body Mass Index; D004359:Drug Therapy, Combination; D005260:Female; D015390:Gastric Bypass / Q000379:methods*; D006221:Halothane / Q000008:administration & dosage* / Q000009:adverse effects; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009609:Nitrous Oxide / Q000008:administration & dosage* / Q000009:adverse effects; D009767:Obesity, Morbid / Q000175:diagnosis / Q000601:surgery*; D010100:Oxygen / Q000008:administration & dosage*; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D018685:Anesthetics, Inhalation; D009609:Nitrous Oxide; D010100:Oxygen; D006221:Halothane