Measurement of residual renal function in patients treated with continuous ambulatory peritoneal dialysis.

Abstract

Renal function contributes markedly to the adequacy of continuous ambulatory peritoneal dialysis (CAPD). The best way to measure it in clinical practice has not been established. Ten stable CAPD patients with residual renal function were investigated to compare the GFR measured as inulin clearance (Cli) with the creatinine clearance (Clc), the urea clearance (Clu), and with 0.5(Clc + Clu). Thereafter, an analysis of whether the administration of cimetidine could improve the accuracy of these clearances was performed. Two clearance periods (CP) of 24 h were investigated. During CP-2, patients received 400 mg cimetidine twice daily, for a total dose of 1200 mg. Two h before the urine and dialysate collection period, inulin was administered iv. Calculations were done for each CP for Cli, Clc, Clu, Clc-Cli, the Clc/Cli ratio, and the tubular secretion of creatinine (TSc). No differences between CP-1 and CP-2 were present for urinary excretion of volume and solutes, and clearance rates of inulin and urea. The median TSc decreased from 0.71 mumol/min (range, -0.24 to 5.90) in CP-1 to 0.30 mumol/min (range, -0.18 to 0.64) in CP-2 (P < 0.05). Therefore, the median ratio of Clc/Cli decreased from 1.23 (range, 0.87 to 2.20) in CP-1 to 1.11 (range, 0.95 to 1.51) in CP-2 (P < 0.05). The median overestimation of the Cli in CP-1 by the Clc was 0.90 mL/min (range, -0.28 to 3.80) and by the 0.5(Clc + Clu) was 0.30 (range, -0.67 to 1.52). The median overestimation of Cli during cimetidine treatment in CP-2 was 0.43 mL/min (range, -0.21 to 1.20). The range, in differences between Cli and Clc, in CP-2 was smaller than that between Cli and 0.5(Clc + Clu) in CP-1. The difference between the clearance rate of inulin and creatinine or the combined clearance rate of urea and creatinine was not influenced by the magnitude of the average GFR. It can be concluded that the administration of cimetidine improved the accuracy of measuring the GFR with the Clc in CAPD patients.

Eosinophilic Reaction at the Time of Catheter Insertion Predicts Survival in Patients Initiating Peritoneal Dialysis

“…In contrast to previous reports, RRF was not associated with technique failure in our study. This inconsistency may be due to the use of eGFR, rather than the arithmetic mean of 24-h urea nitrogen and creatinine clearance, which is the gold standard to assess RRF [25][26][27]. In addition, the rate of RRF decline, which might be a more powerful predictor of technique failure, was not taken into account [27].…”

Kt/V reach rate is associated with clinical outcome in incident peritoneal dialysis patients

“…Cardiovascular disease was defined as a history of angina, class III-IV congestive heart failure, prior myocardial infarction, coronary heart disease, cardiac arrhythmia, cerebrovascular disease, or peripheral vascular disease. RRF was calculated as the mean urea and creatinine clearance from a 24-h urine collection [ 11 ]. nPCR was calculated by the formula: nPCR (g/kg/day) = PCR × 0.58/V, PCR (g/day) = 10.76 × (UNA + 1.46), where UNA (g/d) = [24-h urine volume (L) × urine urea nitrogen(mg/dL) + 24-h dialysate volume (L) × dialysate urea nitrogen (mg/dL)]/100.…”

Peritoneal Protein Clearance Is Associated With Cardiovascular Events but Not Mortality in Peritoneal Dialysis Patients

“…The contribution of urea clearance by PD was estimated separately. For the evaluation of residual renal function (RRF), we used the estimated glomerular filtration rate, calculated as an average of 24-h urine urea and Ccr ( 19 ).…”