title: Peritoneal dialysis fill volume: can the patient tell the difference?
abstract: OBJECTIVE
  Patients on continuous ambulatory peritoneal dialysis (CAPD) must receive an increased dialysis dose as they lose residual renal function so that total clearances are optimized. The dialysis dose may be increased by increasing the exchange volume. Patients on CAPD are often reluctant to use a greater exchange volume, fearing increased pain and discomfort and an altered body image. To assess patient perception of various fill volumes, we studied 12 stable patients currently treated with 2-L exchanges who had no surgical contraindication to larger fill volumes.
  
  
  METHODS
  After an overnight dwell, patients received a 2-L, 2.5-L, or 3-L exchange of Baxter PD4 (Baxter Healthcare SA, Castlebar, Ireland) for 3 hours in a randomized crossover design. Patients and staff were both blinded to the fill volume. At the beginning and end of the exchange, intraperitoneal hydrostatic pressure (IPP) in the supine position was measured, and the patient's perception of the exchange was evaluated using the validated McGill Pain Questionnaire (MPG).
  
  
  RESULTS
  Initial IPP increased with increasing fill volume (12.5 +/- 3.7 cmH2O vs 16.1 +/- 4.2 cmH2O vs 18.7 +/- 3.6 cmH2O for 2, 2.5 L, and 3L, respectively). For all fill volumes, IPP had fallen by the end of the 3-hour dwell, at which time it was similar to that after an overnight 2-L exchange. The pain rating index by was generally low for all exchange volumes and did not correlate with IPP. Minor degrees of discomfort were reported by 4, 2, and 1 patients with 3-L, 2.5-L, and 2-L exchanges respectively.
  
  
  CONCLUSIONS
  Our study suggests that, despite an increased IPP, larger exchange volumes are generally well tolerated by patients, with only a minority of patients feeling mild discomfort.
authors.affiliation: Department of Nephrology, Leicester General Hospital, UK. krgh1@le.ac.uk
authors.forename: K P
authors.initials: KP
authors.lastname: Harris
authors.forename: A M
authors.initials: AM
authors.lastname: Keogh
authors.forename: L
authors.initials: L
authors.lastname: Alderson
mesh_terms: D000328:Adult; D000368:Aged; D018592:Cross-Over Studies; D015314:Dialysis Solutions / Q000008:administration & dosage*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D006874:Hydrostatic Pressure; D008297:Male; D008875:Middle Aged; D010147:Pain Measurement; D010529:Peritoneal Cavity / Q000503:physiopathology; D010531:Peritoneal Dialysis, Continuous Ambulatory / Q000009:adverse effects
chemical_list: D015314:Dialysis Solutions