title: Metabolic and immunologic consequences of laparoscopy with helium or carbon dioxide insufflation: a randomized clinical study.
abstract: BACKGROUND
  Previous studies using animal models have demonstrated that carbon dioxide (CO2) pneumoperitoneum during laparoscopy is associated with adverse physiological, metabolic, immunological and oncological effects, and many of these problems can be avoided by the use of helium insufflation. The present study was performed in patients to compare the effect of helium and CO2 insufflation on intraperitoneal markers of immunological and metabolic function.
  
  
  METHODS
  Eighteen patients undergoing elective upper gastrointestinal laparoscopic surgery were randomized to have insufflation achieved by using either helium (n = 8) or CO2 (n = 10) gas. Intraperitoneal pH was monitored continuously during surgery, and peritoneal macrophage function was determined by harvesting peritoneal macrophages at 5 min and 30 min after commencing laparoscopy, and then assessing their ability to produce tumour necrosis factor-alpha (TNF-alpha), and their phagocytic function.
  
  
  RESULTS
  Carbon dioxide laparoscopy was associated with a lower intraperitoneal pH at the commencement of laparoscopy, although this difference disappeared as surgery progressed. The production of TNF-alpha was better preserved by CO2 laparoscopy, but the insufflation gas used did not affect macrophage phagocytosis. Patients undergoing helium laparoscopy required less postoperative analgesia.
  
  
  CONCLUSIONS
  The choice of insufflation gas can affect intraperitoneal macrophage function in the clinical setting, and possibly acid-base balance. The present study suggested no immunological advantages for the clinical use of helium as an insufflation gas. The outcomes of the present study, however, are different to those obtained from previous laboratory studies and further research is needed to confirm this outcome.
authors.affiliation: University of Adelaide, Department of Surgery, Royal Adelaide Hospital, South Australia, Australia.
authors.forename: S J
authors.initials: SJ
authors.lastname: Neuhaus
authors.forename: D I
authors.initials: DI
authors.lastname: Watson
authors.forename: T
authors.initials: T
authors.lastname: Ellis
authors.forename: T
authors.initials: T
authors.lastname: Lafullarde
authors.forename: G G
authors.initials: GG
authors.lastname: Jamieson
authors.forename: W J
authors.initials: WJ
authors.lastname: Russell
mesh_terms: D002245:Carbon Dioxide / Q000009:adverse effects*; D016099:Endoscopy, Gastrointestinal / Q000009:adverse effects*; D004931:Esophageal Achalasia / Q000276:immunology* / Q000378:metabolism* / Q000601:surgery; D005260:Female; D005764:Gastroesophageal Reflux / Q000276:immunology* / Q000378:metabolism* / Q000601:surgery; D006371:Helium / Q000009:adverse effects*; D006801:Humans; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D010535:Laparoscopy / Q000009:adverse effects*; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D008297:Male; D019990:Perioperative Care; D010537:Peritoneum / Q000187:drug effects / Q000276:immunology* / Q000378:metabolism*; D010587:Phagocytosis / Q000187:drug effects / Q000502:physiology; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects*; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects / Q000276:immunology / Q000378:metabolism
chemical_list: D014409:Tumor Necrosis Factor-alpha; D002245:Carbon Dioxide; D006371:Helium