title: Normal values and differences between intraperitoneal and subcutaneous microdialysis in patients after non-complicated gastrointestinal surgery.
abstract: OBJECTIVE
  Visceral ischemia is an early event in the development of shock and organ failure. Microdialysis has been presented as a promising method for detection of visceral hypoxia and ischemia. The aim of this study was to investigate differences in the metabolic response measured by microdialysis between intraperitoneal and subcutaneous locations and to estimate normal values of lactate/pyruvate ratio, glucose and glycerol.
  
  
  METHODS
  Intraperitoneal and subcutaneous metabolic responses were compared regarding lacate/pyruvate ratio, glucose and glycerol, during 45 postoperative hours in 33 patients undergoing various non-complicated elective major gastrointestinal surgery.
  
  
  RESULTS
  Intraperitoneal lactate/pyruvate ratio started around 15 and decreased over time, while subcutaneous levels were stable around 9. Glucose levels were higher intraperitoneally and increased rapidly during the first 9 h to 8.6 mM, while the subcutaneous levels increased during 21 h to 7.5 mM. Intraperitoneal glycerol levels were stable around 100 microM, while subcutaneous values started around 230 microM and then increased.
  
  
  CONCLUSIONS
  In a non-complicated postoperative course the lactate/pyruvate ratio and glucose levels are higher intraperitoneally, suggesting a higher postoperative intraperitoneal metabolism. Glycerol levels are higher and increase subcutaneously, suggesting increased postoperative energy demand, particularly in the visceral organs, as being responsible for the lipolysis seen in the subcutaneous tissue.
authors.affiliation: Department of Surgery, Orebro University Hospital, Sweden. kjell.jansson@orebroll.se
authors.forename: K
authors.initials: K
authors.lastname: Jansson
authors.forename: M
authors.initials: M
authors.lastname: Jansson
authors.forename: M
authors.initials: M
authors.lastname: Andersson
authors.forename: A
authors.initials: A
authors.lastname: Magnuson
authors.forename: U
authors.initials: U
authors.lastname: Ungerstedt
authors.forename: L
authors.initials: L
authors.lastname: Norgren
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005767:Gastrointestinal Diseases / Q000601:surgery*; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D006801:Humans; D007511:Ischemia / Q000378:metabolism*; D019344:Lactic Acid / Q000378:metabolism; D008297:Male; D017551:Microdialysis / Q000592:standards*; D008875:Middle Aged; D010529:Peritoneal Cavity; D011182:Postoperative Care / Q000592:standards; D011184:Postoperative Period; D019289:Pyruvic Acid / Q000378:metabolism; D012016:Reference Values; D040521:Subcutaneous Tissue / Q000378:metabolism*
chemical_list: D019344:Lactic Acid; D019289:Pyruvic Acid; D005947:Glucose; D005990:Glycerol