title: Chronically increased intra-abdominal pressure: validating a model.
abstract: BACKGROUND
  Pregnancy is the only physiologic condition in which we encounter chronically elevated intra-abdominal pressure (IAP), while pathologically several pathologies, such as ascites and morbid obesity, are affected by this phenomenon. This paper introduces and validates a new model that is able to create and maintain chronically increased IAP, facilitating the study of phenomena related to chronically elevated IAP, i.e., obesity.
  
  
  METHODS
  An experimental device was implanted in 15 rabbits, which consisted of an intra-abdominal balloon (IAB), an external control valve, and a connecting tube. A Foley catheter was inserted in their urinary bladders. IAPs were measured simultaneously transvesically and via the device. During the acute phase, IAB was gradually inflated to 16 cmH(2)O, and IAPs were consecutively measured. During the chronic phase, residual IAPs were measured in a weekly rate for 8 weeks. Statistical significances, mean bias, and precisions were calculated.
  
  
  RESULTS
  During the acute phase, the saline in the IAB efficiently increases IAP to 16 cmH(2)O. IAPs measured both through the urinary bladder and the device correlate well with small bias and high precision. Our model maintains sufficiently chronically increased IAP for at least 8 weeks. No mortality was observed.
  
  
  CONCLUSIONS
  A rabbit model establishing and maintaining chronically increased IAP was successfully created and proved to be simple, effective, and repeatable. This model established chronically increased IAP permitting this way the study of its effect on organs and systems.
authors.affiliation: 3rd Department of Surgery, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece. papavramidis@hotmail.com
authors.forename: Theodossis S
authors.initials: TS
authors.lastname: Papavramidis
authors.forename: Thomai P
authors.initials: TP
authors.lastname: Lazou
authors.forename: Angeliki
authors.initials: A
authors.lastname: Cheva
authors.forename: Orestis J
authors.initials: OJ
authors.lastname: Gamvros
mesh_terms: D000005:Abdomen / Q000502:physiology*; D000818:Animals; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation* / Q000379:methods; D009765:Obesity / Q000150:complications* / Q000503:physiopathology; D011312:Pressure; D011817:Rabbits; D015203:Reproducibility of Results; D001743:Urinary Bladder / Q000502:physiology*; D014546:Urinary Catheterization
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