van Olden R W, Krediet R T, Struijk D G, Arisz L
Department of Medicine, Academic Medical Center, University of Amsterdam, The Netherlands.
J Am Soc Nephrol. 1996 May;7(5):745-50. doi: 10.1681/ASN.V75745.
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.
肾功能对持续性非卧床腹膜透析（CAPD）的充分性有显著影响。在临床实践中测量肾功能的最佳方法尚未确定。对10例具有残余肾功能的稳定CAPD患者进行了研究，以比较菊粉清除率（Cli）测得的肾小球滤过率（GFR）与肌酐清除率（Clc）、尿素清除率（Clu）以及0.5（Clc + Clu）。此后，分析了西咪替丁的给药是否能提高这些清除率的准确性。研究了两个24小时的清除期（CP）。在CP - 2期间，患者每天两次接受400mg西咪替丁，总剂量为1200mg。在尿液和透析液收集期前2小时，静脉注射菊粉。对每个CP计算Cli、Clc、Clu、Clc - Cli、Clc/Cli比值以及肌酐的肾小管分泌（TSc）。CP - 1和CP - 2在尿量和溶质的尿排泄以及菊粉和尿素的清除率方面没有差异。TSc的中位数从CP - 1时的0.71μmol/min（范围，-0.24至5.90）降至CP - 2时的0.30μmol/min（范围，-0.18至0.64）（P < 0.05）。因此，Clc/Cli的中位数比值从CP - 1时的1.23（范围，0.87至2.20）降至CP - 2时的1.11（范围，0.95至1.51）（P < 0.05）。CP - 1中Clc对Cli的中位数高估为0.90mL/min（范围，-0.28至3.80），0.5（Clc + Clu）对Cli的中位数高估为0.30（范围，-0.67至1.52）。CP - 2中西咪替丁治疗期间Cli的中位数高估为0.43mL/min（范围，-0.21至1.20）。CP - 2中Cli与Clc之间的差异范围小于CP - 1中Cli与0.5（Clc + Clu）之间的差异范围。菊粉清除率与肌酐清除率或尿素与肌酐的联合清除率之间的差异不受平均GFR大小的影响。可以得出结论，西咪替丁的给药提高了CAPD患者中用Clc测量GFR的准确性。
