Wang T, Heimbürger O, Waniewski J, Bergström J, Lindholm B
Department of Clinical Science, Karolinska Institute, Huddinge University Hospital, Stockholm, Sweden.
Adv Perit Dial. 1997;13:23-8.
The viability of long-term peritoneal dialysis (PD), especially once residual renal function is lost, has been challenged since recently recommended weekly targets of Kt/V of 2.1 and creatine clearance (Ccr) of 70 L/1.73 m2 may be difficult to reach. This study demonstrates the theoretical possibility of achieving these targets in PD patients even without residual renal function. A 6-hour dwell study was performed in 68 PD patients with frequent dialysate and plasma sampling using 2 L of 1.36% (n = 13), 2.27% (n = 9), or 3.86% glucose dialysate (n = 46) with 131I albumin as an intraperitoneal volume marker. Alterations in fluid balance, Kt/V, and Ccr with dwell time (t) as well as the impact of peritoneal fluid absorption on peritoneal fluid and solute removal were evaluated. Kt/V and Ccr did not follow an exponential function with t and, in fact, decreased after 4-5 hours, especially in high transporters. All patients could achieve either weekly Kt/V (especially low transporters) or Ccr target (especially high transporters) if they are treated with automated PD. Calculations showed that eliminating fluid absorption could increase mean fluid removal by 43%-179%, increase mean Kt/V by 17%-32%, and mean Ccr by 16%-30% (depending on the solution used and the patient's peritoneal transport pattern) during a 6-hour dialysis exchange. We reached the following conclusions: (1) Kt/V(urea) and Ccr are markedly time-dependent during a single exchange due to the substantial impact of peritoneal absorption and may, in fact, decline after 4 hours, especially in high transporters. (2) Extrapolating Kt/V and Ccr values from short dwell times [i.e., peritoneal equilibration test (PET) results] to long dwell times will overestimate the peritoneal clearances. (3) Enough fluid removal must be considered as an important target of adequate dialysis along with small solute clearances. (4) If fluid absorption could be eliminated, most continuous ambulatory peritoneal dialysis (CAPD) patients could achieve the recommended Kt/V and/or Ccr targets even without residual renal function.
长期腹膜透析（PD）的可行性，尤其是一旦残余肾功能丧失后，受到了挑战，因为最近推荐的每周Kt/V目标值2.1和肌酐清除率（Ccr）70 L/1.73 m²可能难以达到。本研究证明了即使在没有残余肾功能的PD患者中实现这些目标的理论可能性。对68例PD患者进行了一项为期6小时的驻留研究，频繁采集透析液和血浆样本，使用2 L的1.36%（n = 13）、2.27%（n = 9）或3.86%葡萄糖透析液（n = 46），以131I白蛋白作为腹腔内容量标记物。评估了液体平衡、Kt/V和Ccr随驻留时间（t）的变化，以及腹膜液吸收对腹膜液和溶质清除的影响。Kt/V和Ccr并不随t呈指数函数变化，实际上在4 - 5小时后下降，尤其是在高转运者中。如果采用自动化腹膜透析治疗，所有患者都可以实现每周的Kt/V目标（尤其是低转运者）或Ccr目标（尤其是高转运者）。计算表明，在6小时的透析交换过程中，消除液体吸收可使平均液体清除量增加43% - 179%，平均Kt/V增加17% - 32%，平均Ccr增加16% - 30%（取决于所用溶液和患者的腹膜转运模式）。我们得出以下结论：（1）由于腹膜吸收的重大影响，单次交换期间Kt/V（尿素）和Ccr明显依赖时间，实际上在4小时后可能下降，尤其是在高转运者中。（2）将短驻留时间（即腹膜平衡试验（PET）结果）的Kt/V和Ccr值外推至长驻留时间会高估腹膜清除率。（3）除了小分子溶质清除外，必须将足够的液体清除视为充分透析的一个重要目标。（4）如果能够消除液体吸收，即使没有残余肾功能，大多数持续性非卧床腹膜透析（CAPD）患者也可以实现推荐的Kt/V和/或Ccr目标。
