Design and assessment of the new APS dialyzer (APS-SA series)

Dialyzer performance seems to greatly depend on the hollow-fiber membrane performance, the morphology of the hollow-fiber membrane bundles (e.g., wave-shaped hollow-fiber membrane bundles), and the design of the dialyzer housing. Consequently, we developed the APS dialyzer APS-SA series, equipped with wave-shaped hollow-fiber membrane bundles as an optimal three-dimensional morphology along with new housings, to realize enhanced dialysis performance. Incorporation of a new type of housing, including a full baffle structure and a short taper section, and a new type of morphology for the hollow-fiber membrane bundles have been verified to allow the dialysate to diffuse uniformly along the full baffle panel around the circumference and to fully permeate into the core of the hollow-fiber bundle. As a result, the APS-SA series has been proved to have achieved enhanced diffusion performance and increased clearance of small molecule solutes such as urea and creatinine, compared with conventional dialyzers. This series is expected to provide increased Kt/V values and dialysate-saving performance in future clinical use.