Hulko Michael, Haug Ulrike, Gauss Julia, Boschetti-de-Fierro Adriana, Beck Werner, Krause Bernd
Research & Development, Baxter International Inc.
Global Medical Affairs, Baxter International Inc., Hechingen, Germany.
Artif Organs. 2018 Dec;42(12):1164-1173. doi: 10.1111/aor.13278. Epub 2018 Oct 3.
Sieving coefficients reported in dialyzer data sheets and instructions for use (IFUs) indicate the potential of different solutes to pass across a particular membrane. Despite being measured in vitro, sieving coefficient data are often used as a predictor of the clinical performance of dialyzers. Although standards for the measurement of sieving coefficients exist, the stated methodologies do not offer sufficient guidance to ensure comparability of test results between different dialyzers. The aim of this work was to investigate the relationship between sieving coefficients and published clinical performance indicators for two solutes, albumin loss and beta-2 microglobulin (β M) reduction ratio (RR), and to assess the impact of different in vitro test parameters on sieving coefficient values for albumin, β M, and myoglobin. Clinical albumin loss and β M RR for commercially available dialyzers used in hemodialysis (HD) and post-dilution hemodiafiltration (HDF) were extracted from the literature and plotted against sieving coefficients reported in data sheets and IFUs. Albumin, β M, and myoglobin sieving coefficients of a selection of dialyzers were measured per the ISO 8637 standard. The impact of in vitro testing conditions was assessed by changing blood flow rate, ultrafiltration (UF) rate, sampling time, and origin of test plasma. Results showed variation in albumin loss and β M RR for the same sieving coefficient across different dialyzers in HD and HDF. Changes in blood flow rates, UF rates, sampling time, and test plasma (bovine vs. human) caused marked differences in sieving coefficient values for all investigated solutes. When identical testing conditions were used, sieving coefficient values for the same dialyzer were reproducible. Testing conditions have a marked impact on the measurement of sieving coefficients, and values should not be compared unless identical conditions are used. Further, variability in observed clinical data in part reflects the lack of definition of test conditions.
透析器数据表和使用说明书（IFU）中报告的筛系数表明了不同溶质穿过特定膜的可能性。尽管筛系数是在体外测量的，但该数据常被用作透析器临床性能的预测指标。虽然存在筛系数测量标准，但既定方法并未提供足够指导以确保不同透析器之间测试结果的可比性。本研究的目的是探讨两种溶质（白蛋白损失和β-2微球蛋白（βM）清除率（RR））的筛系数与已发表的临床性能指标之间的关系，并评估不同体外测试参数对白蛋白、βM和肌红蛋白筛系数值的影响。从文献中提取了用于血液透析（HD）和后置稀释血液透析滤过（HDF）的市售透析器的临床白蛋白损失和βM RR，并将其与数据表和IFU中报告的筛系数进行对比。按照ISO 8637标准测量了所选透析器的白蛋白、βM和肌红蛋白筛系数。通过改变血流速率、超滤（UF）速率、采样时间和测试血浆来源来评估体外测试条件的影响。结果显示，在HD和HDF中，不同透析器对于相同筛系数的白蛋白损失和βM RR存在差异。血流速率、UF速率、采样时间和测试血浆（牛血浆与人血浆）的变化导致所有研究溶质的筛系数值出现显著差异。当使用相同测试条件时，同一透析器的筛系数值具有可重复性。测试条件对筛系数的测量有显著影响，除非使用相同条件，否则不应比较数值。此外，观察到的临床数据的变异性部分反映了测试条件定义的缺失。
