No abstract

These data suggest that solute transfer increases and UF declines with time on peritoneal dialysis. This process is exacerbated and accelerated by peritonitis, and appears to be proportional to the degree of associated inflammation and number of infections in close proximity.

A total of 143 Peritoneal Equilibration Tests (PETs) were performed in 104 CAPD patients over a period of 18 months. A normal range (95% confidence limits) was constructed from 100 tests (68 consecutive new patients, 32 routine tests on problem-free patients) using a 2-dimensional plot of solute transfer (D/Pcreat) and ultrafiltration volume. These two parameters correlated inversely (r = -0.59, P < 0.0001) allowing calculation of a regression line. In the short term (< 3 months) D/Pcreat was stable across a wide range of values (0.45-0.98) with good correlation between tests indicating reproducibility (r = 0.94, P < 0.001). Repeated tests beyond 3 months were variable, explaining changes in the clinical picture, and in the majority of cases shifts in D/Pcreat and ultrafiltration parallelled the regression line for the whole population. Six of seven (85%) of patients with mechanical problems and 14 of 15 (93%) with poor ultrafiltration had at least one abnormal test, and these two problems could be distinguished in 90% of cases by 2-dimensional plotting. In five with ultrafiltration failure, dialysate volumes were less than predicted by solute clearance, and these patients failed continuous cycling peritoneal dialysis (CCPD). In contrast, a good response to CCPD was predicted correctly in five patients with high solute clearance. In nine patients with plasma creatinine > 1250 mumol/l the PET was normal. The PET is a useful adjunct to understanding and prescribing peritoneal dialysis, particularly when repeated tests are compared to a well-defined normal population.

Comorbidity, age, dialysis dose (KT/Vurea)’ plasma albumin, and peritoneal function (DIP treat) were measured cross-sectionally in 228 continuous ambulatory peritoneal dialysis (CAPD) patients, who were then followed up for a mean of two years. Comorbidity, utilizing a semiquantitative score described previously, was the most powerful predictor of mortality in both univariate and multivariate analysis. Using univariate analysis, all the variables predicted outcome with statistical significance, mortality being associated with lower KT/V and plasma albumin and a higher DIP treat On multivariate analysis only comorbidity, age, and KT/V remained independent predictors. Data was further analyzed on the basis of type of comorbid condition. In those patients without comorbid disease (n = 127) neither KT/V, albumin nor DIP retreamendicted outcome. In patients with clinical evidence of ischemic heart disease the KT/V was a significant predictor of favorable outcome. In those with clinical evidence of left ventricular function, mortality was significantly and independently associated with low plasma albumin, high DIP treat’ and KT/V. It is suggested that the concept of treatment adequacy in CAPD patients must include both measures of dialysis dose and peritoneal function, particularly in the context of the patient's comorbidity.