EVALUATION OF NONLINEAR AND LINEAR MATHEMATICAL-MODELS FOR CREATININEAND GLUCOSE FITTING IN PERITONEAL-DIALYSIS

Four non-linear and five linear models for predicting the creatinine d ialysate/plasma ratio (CRD/P) and the glucose dialysate/initial concen tration ratio (GLD/Do) were evaluated in a group of 31 patients on per itoneal dialysis and subjected to the peritoneal equilibration test (P ET 3.86%, 240'). PET results and classification were compared to obtai n a definition of patient peritoneal transport characteristics. The mo nomolecular and rectangular hyperbola non-linear models, the Lineweave r-Burk, Hanes-Woolf and Dadone linear transformations were considered for the CRD/P fitting. A monoexponential and two-exponential decay plu s the semilogarithmic transformations were considered for the GLD/Do. These models are simple, accurate and functionally homogeneous. Furthe r studies are advisable however on the individual peritoneal transport classification, since similar to 30% of the patients were in differen t categories for CRD/P and GLD/Do and the fittings do not give better classification results.