How can dialyzer designs improve solute clearances for hemodialysis patients?

Abstract

Improvements in dialyzer technology and design have led to a reduction in both dialyzer size and cost, but also dialysis session treatment times as hemodialysis has evolved from using the cellulosic coiled drum dialyzer to the flat plate Kiil, to the current generation of hollow fiber capillary dialyzers. Newer manufacturing techniques have led to smoother, more consistent pore sizes and larger pore sizes increasing middle molecule clearances with the development of higher permeability dialyzers, and changing polymer composition to increase hydraulic permeability. Modifications to the dialyzer casing and capillary fibers can also increase the efficiency of solute clearances. Although very efficient in removing the smaller water-soluble azotemic toxins, the current generation of dialyzers is not so effective in removing other azotemic toxins, including protein-bound solutes, necessitating the development of newer designs.

Platelet activation and clotting cascade activation by dialyzers designed for high volume online hemodiafiltration

“…5 However, it was soon realized that these dialyzers activated complement, platelets, and leukocytes. 18 However, clinical trials designed to investigate the effect of greater urea clearance did not show any benefit in terms of patient survival, and despite the technical advances in dialysis technology 5-year patient survival remained lower than that for some of the more common solid organ cancers. 16 These newer dialyzer membranes, and changes in dialyzer sterilization processes, reduced reactions to hemodialysis, 17 and as such further developments in dialyzer design were aimed at increasing small solute urea clearances.…”

Optimization of anti-infective dosing regimens during online haemodiafiltration

“…The surface area of the dialyser is the maximal area available for blood contact and is directly related to the clearance of low MW solutes [6]. …”

UK Renal Registry 19th Annual Report: Chapter 6 Adequacy of Haemodialysis in UK Adult Patients in 2015: National and Centre-specific Analyses

“…It is reassuring that the proportion of UK haemodialysis patients achieving this target URR has increased from 2002, with now more than 88% of the prevalent HD population achieving the guideline target in 2015. This improvement in delivered dialysis dose reflects improvements in not only clinical practice and haemodialysis technology [15], but also enhanced coverage and quality of the data collected by the UKRR from renal centres over time.…”