title: Mini-peritoneal equilibration test: A simple and fast method to assess free water and small solute transport across the peritoneal membrane.
abstract: BACKGROUND
  Loss of ultrafiltration (UF) of peritoneal membrane is one of the most important causes of peritoneal dialysis failure. UF is determined by osmotic forces acting mainly across small pores (UFSP) and ultrasmall pores or free water transport. At present, only semiquantitative estimates or complicated computer simulations are available to assess free water transport. The aim of this study was to assess free water transport during a 3.86% peritoneal equilibration test lasting 1 hour. In this condition, sodium transport is mainly due to convection, allowing the estimate of ultrafiltration of small pores and then of free water transport (total UF - UFSP).
  
  
  METHODS
  In 52 peritoneal dialysis patients we performed a 3.86% peritoneal equilibration test (4 hours) and a 3.86% mini-peritoneal equilibration test (1 hour) and compared UF and small solute transports obtained with the two methods.
  
  
  RESULTS
  During the 3.86% mini-peritoneal equilibration test, UFSP and free water transport were 279 +/- 142 mL and 215 +/- 86 mL, respectively; free water transport well correlated to total UF during the 3.86% peritoneal equilibration test (r= 0.67). The groups of peritoneal transporters, categorized according to glucose dialysate ratio (D/D(0)) and to creatinine/plasma ratio (D/P(Creat)), were in good agreement for the two peritoneal equilibration tests (weighted kappa 0.62 and 0.61, respectively).
  
  
  CONCLUSIONS
  The 3.86% mini-peritoneal equilibration test is a simple and fast method to assess free water transport. It also gives information about total UF and small solute transports and it is in good agreement with the 3.86% peritoneal equilibration test.
authors: Department of Nephrology and Dialysis, A. Manzoni Hospital, Lecco, Italy.
authors: Vincenzo
authors: V
authors: La Milia
authors: Salvatore
authors: S
authors: Di Filippo
authors: Monica
authors: M
authors: Crepaldi
authors: Lucia
authors: L
authors: Del Vecchio
authors: Cesare
authors: C
authors: Dell'Oro
authors: Simeone
authors: S
authors: Andrulli
authors: Francesco
authors: F
authors: Locatelli
mesh_terms: D000328:Adult; D000368:Aged; D015314:Dialysis Solutions / Q000493:pharmacokinetics; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000378:metabolism / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D008954:Models, Biological; D009997:Osmotic Pressure; D010530:Peritoneal Dialysis; D010537:Peritoneum / Q000378:metabolism*; D014867:Water / Q000378:metabolism*
chemical_list: D015314:Dialysis Solutions; D014867:Water