title: Heated and humidified CO2 prevents hypothermia, peritoneal injury, and intra-abdominal adhesions during prolonged laparoscopic insufflations.
abstract: BACKGROUND
  Insufflation with standard cold-dry CO(2) during laparoscopic surgery has been shown to predispose patients to hypothermia and peritoneal injury. This study aimed to compare the effect of prolonged cold-dry CO(2) insufflation with heated-humidified CO(2) insufflation (3-5 h) on hypothermia, peritoneal damage, and intra-abdominal adhesion formation in a rat model.
  
  
  METHODS
  A total of 160 Wistar rats were randomized to undergo no insufflation or insufflation with cold-dry CO(2) (21 degrees C, <1% relative humidity) or heated-humidified CO(2) (37 degrees C, 95% relative humidity) for 3, 4, or 5 h. Core body temperature was measured via rectum before and during insufflations. Peritoneal samples were taken at 6, 24, 48, and 96 h after treatments and analyzed with light microscopy and scanning electron microscopy. Intra-abdominal adhesions were evaluated 2 weeks later.
  
  
  RESULTS
  Core body temperature significantly decreased in the cold-dry group, whereas it was maintained and increased in the heated-humidified group. Scanning electron microscopy and light microscopy studies showed intense peritoneal injury in the cold-dry CO(2) group but significantly less damages in the heated-humidified group. Increased intra-abdominal adhesion formation was observed in the cold-dry CO(2) group, while no adhesions were found in the rats insufflated with heated-humidified CO(2).
  
  
  CONCLUSIONS
  Heated-humidified CO(2) insufflation results in significantly less hypothermia, less peritoneal damage, and decreased adhesion formation as compared with cold-dry CO(2) insufflation. Heated-humidified CO(2) may be more suitable for insufflation application in prolonged laparoscopic surgery.
authors.affiliation: Department of General Surgery, Shanghai Minimally Invasive Surgery Center, Shanghai Jiaotong University School of Medicine, Shanghai, China. pengyuanfei@msn.com
authors.forename: Yuanfei
authors.initials: Y
authors.lastname: Peng
authors.forename: Minhua
authors.initials: M
authors.lastname: Zheng
authors.forename: Qing
authors.initials: Q
authors.lastname: Ye
authors.forename: Xuehua
authors.initials: X
authors.lastname: Chen
authors.forename: Beiqing
authors.initials: B
authors.lastname: Yu
authors.forename: Bingya
authors.initials: B
authors.lastname: Liu
mesh_terms: D000818:Animals; D001831:Body Temperature / Q000502:physiology; D002245:Carbon Dioxide / Q000008:administration & dosage* / Q000494:pharmacology*; D006358:Hot Temperature; D006813:Humidity; D007035:Hypothermia / Q000503:physiopathology / Q000517:prevention & control*; D007327:Insufflation / Q000009:adverse effects* / Q000379:methods; D010535:Laparoscopy / Q000009:adverse effects* / Q000379:methods; D008297:Male; D023421:Models, Animal; D010537:Peritoneum / Q000187:drug effects / Q000293:injuries* / Q000473:pathology; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors; D000267:Tissue Adhesions / Q000473:pathology / Q000517:prevention & control*
chemical_list: D002245:Carbon Dioxide