Catherine Firanek

♦ Background: The use of automated and continuous ambulatory peritoneal dialysis (APD and CAPD) prescriptions (Rxs) to achieve adequate uremic toxin and fluid removal targets is important for attaining optimal patient outcomes. One approach for predicting such Rxs is the use of kinetic modeling. ♦ Methods: Demographic data and peritoneal membrane characteristics derived from a peritoneal equilibration test (PET) were available from 1,005 patients in North American centers who participated in a national adequacy initiative in 1999. Twelve patient subgroups were identified according to peritoneal membrane transport type and tertiles of total body water, assumed equal to urea distribution volume (Vurea). Each patient was then modeled using PD Adequest 2.0 to be treated by 12 CAPD and 34 APD Rxs using both glucose and icodextrin solutions to achieve adequacy targets of weekly urea Kt/V of 1.7 and 1 L of daily ultrafiltration (UF). Residual kidney function (RKF) was assumed to be 0, 2, 4, and 6 mL/min. Feasible peritoneal dialysis (PD) Rxs were identified where: 1) the 95% confidence limit achieved the goal of meeting the targets for urea Kt/V, daily UF, and both in 85%, 75%, and 70% of patients, respectively; 2) average PD solution dextrose concentration was <2.5%; and 3) the number of daytime exchanges was minimized. ♦ Results: Feasible PD Rxs were similar when RKF was ≥ 2 mL/min, allowing condensed recommendations based on RKF ≥ 2 mL/min or < 2 mL/min. Individuals with lower or slower membrane transport required relatively greater 24-h solution volumes to achieve adequacy targets when RKF fell below 2 mL/min. With increasing Vurea, there was disproportionately greater dependence on RKF to achieve targets. While multiple Rxs achieving urea Kt/V and daily UF goals were identified for all membrane transport types, use of icodextrin in the long dwell reduced the need for a midday exchange in APD, glucose exposure, required fill and 24-h dwell volumes, irrespective of RKF and Vurea. While these benefits were most notable in high and high-average transporters, similar results were also seen in low and low-average transporters. ♦ Conclusions: Kinetic modeling identified multiple APD and CAPD Rxs that achieved adequate uremic solute and fluid removal for patients, irrespective of RKF and Vurea. Use of icodextrin rather than glucose in the long dwell reduced the complexity of the PD regimen, total glucose exposure, and 24-h total treatment solution volumes. Irrespective of modeling, adequacy of any PD prescription should be based upon individual.

To determine if the previously described peritoneal equilibration test (PET)-determined solute transport groups, as defined by Twardowski, fit our patient population. We reviewed the 195 initial standardized PETs (on 195 patients) performed through our peritoneal dialysis program since 1989. Using the method originally defined by Twardowski using the means and standard deviations of the PET-determined dialysis/plasma ratio (D/P) of creatinine and dialysate-to-0 hour dialysate (D/D0) glucose values, transport groupings for our patient population were determined. Comparisons were then made between patient populations. The mean 4-hour D/P creatinine in our patients was 0.70 +/- 0.10. This compares to a mean of 0.65 +/- 0.15 as determined by Twardowski, and indicates that our patients have higher mean solute transport characteristics and tighter ranges within transport groups than previously reported. Only 2% of our patients fell into the previously described low (L) range, with 30% low...

The relationship between quality of life (QofL) and anemia has been the subject of recent debates; it has been suggested that the QofL changes associated with the treatment of anemia of chronic kidney disease (CKD) or ESRD patients should not be used in making decisions to treat anemia in CKD patients. This study examines the relationship between Kidney Disease Quality of Life (KDQofL) questionnaire domains and hemoglobin (Hgb) levels in 1200 patients with stage 3, 4, and 5 CKD followed in seven centers. QofL measures were compared in a stepwise fashion for hemoglobin levels of <11, 11 to <12, 12 to <13, and > or =13. ANOVA was used to examine the relationship between QofL scores and Hgb level, age, CKD stage, and albumin level; a history of diabetes, congestive heart failure, or myocardial infarction; use of erythropoetic-stimulating agents (ESA); and the interaction of hemoglobin level and ESA. The results demonstrate that with increasing Hgb levels there is a statistically significant increase in all four physical domains, the energy/vitality domain, and the physical composite score of the SF-36, and the general health score on the kidney disease component of the questionnaire. The most dramatic improvements in these various domains occurred between the <11 and the 11 to 12 group. Higher Hgb levels are associated with improved QofL domains of the KDQofL questionnaire. These findings have implications for the care of CKD patients in terms of the initiation of and the Hgb target of ESA therapy.