Extracorporeal dialysis: techniques and adequacy

Abstract

Introduction and Aims: Biocompatibility of hemodialysis (HD) membranes is the most important quality criteria to enable long-term HD. Shear stress and the contact between blood and non-human materials during HD generate platelet-derived microparticles (PDMPs). It is considered that PDMPs contribute to the development of thrombotic complications and atherosclerosis associated with increases in their plasma levels. The polysulfone (PSf ) HD membrane is becoming the mainstream in HD treatment because of its high performance. Most of PSf membranes are hydrophilized by polyvinylpyrrolidone (PVP) to improve biocompatibility, however, platelets still adhere to the surface of membrane and activate platelets. We could use new PSf HD membranes coated with a new hydrophilic polymer instead of PVP and it has been shown that platelets hardly adhered at the surface of membrane. This study sought to evaluate the differences of biocompatibility using 2 different types of PSf HD membranes. Methods: We conducted prospective, randomized, open-label trial for 3 months in HD patients treated with PSf HD membrane (APS: Asahi-medical, Japan, PVP(+)). Twenty-four patients were randomly divided into 2 groups; i.e., APS group (n=12) and another PSf HD membrane, NV (Toray-medical, Japan, PVP(-)) group (n=12). We analyzed the plasma levels of PDMPs and flow-mediated dilatation (FMD) of the brachial artery before and after 3 months. Results: Data are given as mean + SD. Age, sex, and HD duration were not different between 2 groups. Treatment with APS membranes did not significantly affect the levels of PDMPs (11.8 + 2.2 to 12.1 + 3.2 U/mL, p=0.76) and FMD (2.3 + 1.5% to 2.7 + 0.9, p=0.41). However, after HD with NV membranes for 3 months PDMPs levels significantly decreased (16.7 + 8.1 to 15.0 + 6.1 U/mL, p=0.04) and FMD increased (3.0 + 1.8 to 4.1 + 1.9 %, p=0.04). Conclusions: The type of HD membrane determines the effects on arterial endothelial function. Differences in biocompatibility may account for the observed differential effects and it might be associated with a reduction in plasma PDMPs level.