title: Carbon dioxide pneumoperitoneum is associated with increased liver metastases in a rat model.
abstract: BACKGROUND
  In patients with primary colorectal cancer, liver metastases are the most important indicators of prognosis and survival; the effect of laparoscopic surgery on the development of hepatic tumor spread is still largely unknown.
  
  
  METHODS
  Thirty WAG/Rij rats were randomly divided into 3 operative groups for intraportal tumor cell inoculation: carbon dioxide pneumoperitoneum (group I, n = 10), gasless laparoscopy (group II, n = 10) and open laparotomy (group III, n = 10). The total operating time was 90 minutes with tumor cell injection (50,000 CC531 colon carcinoma cells/mL) performed 45 minutes after the start of the procedure. Hepatic tumor growth and the total tumor load were evaluated 28 days after surgery.
  
  
  RESULTS
  Hepatic tumor growth and total tumor load were significantly reduced in the gasless laparoscopy group (group II) as compared with the carbon dioxide pneumoperitoneum group (group I) and the open laparotomy group (group III) (P < .05). No significant difference was found between the carbon dioxide and the open laparotomy groups.
  
  
  CONCLUSIONS
  Insufflation of carbon dioxide may actually stimulate metastatic disease of the liver. Gasless laparoscopy seems to preserve hepatic resistance against tumor growth.
authors.affiliation: Department of General and Vascular Surgery, Johann Wolfgang Goethe-University, Frankfurt/Main, Germany.
authors.forename: C N
authors.initials: CN
authors.lastname: Gutt
authors.forename: Z G
authors.initials: ZG
authors.lastname: Kim
authors.forename: T
authors.initials: T
authors.lastname: Schmandra
authors.forename: V
authors.initials: V
authors.lastname: Paolucci
authors.forename: M
authors.initials: M
authors.lastname: Lorenz
mesh_terms: D000818:Animals; D002245:Carbon Dioxide; D003110:Colonic Neoplasms / Q000473:pathology; D010535:Laparoscopy / Q000009:adverse effects; D007813:Laparotomy / Q000009:adverse effects; D008114:Liver Neoplasms, Experimental / Q000556:secondary*; D008297:Male; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects*; D051381:Rats; D011919:Rats, Inbred Strains; D014407:Tumor Cells, Cultured
chemical_list: D002245:Carbon Dioxide