Initial clinical experience with a new model of mass transfer for peritoneal dialysis.

A clinical pilot study compared predictions of a new model of peritoneal dialysis mass transfer to measured weekly KT/V urea (KTu/V) and weekly creatinine clearance (Ccr) in liters per 1.73 m2 in 50 patients from five centers (40 CAPD, 10 CCPD). The Robertson et al. model is unique in that it does not require a 24-hour collection of dialysate. Instead, model predictions are based on the results of a standard 4-hour peritoneal equilibration test (PET) and appropriate demographic data. Analysis revealed 12 collection errors, 8 affecting the PET and 4 affecting 24-hour dialysate volume. PET drainage volume was low in six cases, excessive in two; 24-hour volume was incomplete in three, excessive in one. Similar errors were not found in the remaining 38 patients. In the 38 patients with correctly performed PET and dialysate collections, agreement between predicted and measured values was excellent.