title: Body position, age and mass effect of adiposity on adipose tissue red cell flux in morbid obesity.
abstract: OBJECTIVE
  To measure red cell flux of adipose tissue in morbidly obese patients' pannus in the upright and supine position to determine factors which would render the lower pannus susceptible to ischemic necrosis.
  
  
  METHODS
  A cohort study of morbidly obese subjects without ischemic necrosis.
  
  
  METHODS
  University teaching hospital.
  
  
  METHODS
  Twenty-three consecutive morbidly obese patients referred for gastroplasty.
  
  
  METHODS
  Red cell flux, measured as RMS voltage by a laser Doppler velocimeter. An optical fiber with a tip diameter of 250 mu was inserted into the upper and lower pannus and output recorded in the upright and supine positions. Other variables recorded were age, BMI, blood pressure and serum lipids.
  
  
  RESULTS
  Adipose tissue red cell flux demonstrates considerable spatial and temporal heterogeneity from subject to subject and in various locations in the pannus. No differences in red cell flux were detected in response to change in position. However, regression analysis demonstrated that the gradient between the upper and lower abdomen in the supine position was increasingly positive with age and in the upright position it was increasingly positive with increasing weight or BMI.
  
  
  CONCLUSIONS
  These data suggest that red cell flux is heterogeneously distributed in the abdominal pannus and is not greatly influenced by body position. However, with increasing age and adiposity there is a gradient for decreased red cell flux to the lower portion of the pannus. This may be a factor in rendering this part of the pannus prone to ischemic fat necrosis.
authors.affiliation: Department of Medicine, Dalhousie University, Halifax, N.S., Canada.
authors.forename: G A
authors.initials: GA
authors.lastname: Klassen
authors.forename: D
authors.initials: D
authors.lastname: Janigan
authors.forename: B
authors.initials: B
authors.lastname: Paton
authors.forename: J
authors.initials: J
authors.lastname: Mathews
authors.forename: B
authors.initials: B
authors.lastname: Perey
authors.forename: A S
authors.initials: AS
authors.lastname: Macdonald
authors.forename: K D
authors.initials: KD
authors.lastname: Barclay
mesh_terms: D000005:Abdomen; D000273:Adipose Tissue / Q000098:blood supply*; D000328:Adult; D000368:Aged; D000375:Aging; D000818:Animals; D015992:Body Mass Index; D015331:Cohort Studies; D005260:Female; D006801:Humans; D017078:Laser-Doppler Flowmetry; D008297:Male; D008875:Middle Aged; D009767:Obesity, Morbid / Q000503:physiopathology*; D011187:Posture; D011817:Rabbits; D012044:Regression Analysis; D016683:Supine Position