Flummoxed by flux: the indeterminate principles of haemodialysis.
Flummoxed by flux: the indeterminate principles of haemodialysis.
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DOI：
10.1093/ckj/sfab182
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发表时间：
2021-12
影响因子：
4.6
通讯作者：
Misra M
中科院分区：
文献类型：
--
作者：
Bowry SK;Kircelli F;Misra M
在血液透析(HD)中，尿毒症中积聚的不需要的物质(尿毒症滞留溶质或尿毒症毒素)通过半透膜运输从血液中清除。像所有的膜分离过程一样，传输需要驱动力来促进分子在膜上的传输。传输量的大小是通过“通量”现象来量化的，“通量”是一个有限的参数，定义为单位时间内每单位面积膜表面转移的流体(或渗透液)的体积。在HD中，由于施加跨膜压力以促进流体通过膜的流动或通量以增强溶质去除，通量由反映膜的水力渗透性的超滤系数(Kuf；毫升/小时/毫米汞)定义。然而，在HD中，通量的指定已被用于更广泛的意义，该术语通常与膜分离过程的其他措施互换和错误地使用，导致相当大的混乱。尽管膜和治疗的其他属性决定了HD期间达到的通量的大小，但通量的增加被认为反映了具有更大的孔的更多的“多孔”膜。通量的形容词名称(低、中、高、超、超)在科学文献中被不分青红皂白地用来限定影响临床决策和治疗方式(低通量或高通量HD)处方的参数。多年来，作者在出版物、监管机构(美国食品和药物管理局)和专业协会指南(欧洲肾脏协会、肾脏疾病结果质量倡议)中对通量的概念和定义进行了任意和定期的调整和重新定义，但几乎没有达成共识。行业已经扩大了通量的界限，以获得营销优势，证明增加报销或设计新的治疗方式类别是合理的，而事实上通量只是决定膜或透析器性能的几个规格之一。以前被认为是高通量的膜现在处于通量谱的低端。此外，与扩散或对流输送速率(通量)无关的附加参数与Kuf一起使用或代替Kuf来暗示通量：清除量(毫升/分钟，例如β2-微球蛋白)或筛分系数(无量纲)。考虑到肾病临床试验旨在提出治疗建议并指导具有经济影响的政策，是基于值得监管当局和科学家澄清的参数流量，以避免进一步挪用。
In haemodialysis (HD), unwanted substances (uraemic retention solutes or ‘uraemic toxins’) that accumulate in uraemia are removed from blood by transport across the semipermeable membrane. Like all membrane separation processes, the transport requires driving forces to facilitate the transfer of molecules across the membrane. The magnitude of the transport is quantified by the phenomenon of ‘flux’, a finite parameter defined as the volume of fluid (or permeate) transferred per unit area of membrane surface per unit time. In HD, as transmembrane pressure is applied to facilitate fluid flow or flux across the membrane to enhance solute removal, flux is defined by the ultrafiltration coefficient (KUF; mL/h/mmHg) reflecting the hydraulic permeability of the membrane. However, in HD, the designation of flux has come to be used in a much broader sense and the term is commonly used interchangeably and erroneously with other measures of membrane separation processes, resulting in considerable confusion. Increased flux is perceived to reflect more ‘porous’ membranes having ‘larger’ pores, even though other membrane and therapy attributes determine the magnitude of flux achieved during HD. Adjectival designations of flux (low-, mid-, high-, super-, ultra-) have found indiscriminate usage in the scientific literature to qualify a parameter that influences clinical decision making and prescription of therapy modalities (low-flux or high-flux HD). Over the years the concept and definition of flux has undergone arbitrary and periodic adjustment and redefinition by authors in publications, regulatory bodies (US Food and Drug Administration) and professional association guidelines (European Renal Association, Kidney Disease Outcomes Quality Initiative), with little consensus. Industry has stretched the boundaries of flux to derive marketing advantages, justify increased reimbursement or contrive new classes of therapy modalities when in fact flux is just one of several specifications that determine membrane or dialyser performance. Membranes considered as high-flux previously are today at the lower end of the flux spectrum. Further, additional parameters unrelated to the rate of diffusive or convective transport (flux) are used in conjunction with or in place of KUF to allude to flux: clearance (mL/min, e.g. of β2-microglobulin) or sieving coefficients (dimensionless). Considering that clinical trials in nephrology, designed to make therapy recommendations and guide policy with economic repercussions, are based on the parameter flux they merit clarification—by regulatory authorities and scientists alike—to avoid further misappropriation.
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DOI：
10.1159/000321750
发表时间：
2011-01-01
期刊：
HEMODIAFILTRATION: A NEW ERA
影响因子：
--
作者：
Glorieux, Griet;Vanholder, Raymond
通讯作者：
Vanholder, Raymond
影响因子：
1.6
作者：
Huang, Zhongping;Gao, Dayong;Clark, William R.
通讯作者：
Clark, William R.
影响因子：
4.2
作者：
Gottschalk, CW;Fellner, SK
通讯作者：
Fellner, SK
影响因子：
13.2
作者：
Daugirdas, John T.;Depner, Thomas A.;Weiner, Daniel E.
通讯作者：
Weiner, Daniel E.
影响因子：
2.3
作者：
Donadio, Carlo;Tognotti, Danika;Paolicchi, Aldo
通讯作者：
Paolicchi, Aldo