Mo658polyvinylpyrrolidone in Hemodialysis Membranes: Impact on Platelet Loss During Hemodialysis

Abstract

Background and Aims Hydrophilic modification with polyvinylpyrrolidone (PVP) increases the biocompatibility profile of synthetic dialysis membranes. However, PVP may be eluted into patient’s blood, which has been discussed as a possible cause for adverse reactions rarely occurring with synthetic membranes. We now investigated the content of PVP and its elution from the blood-side surface from commercially available dialyzers, including the novel FX CorAL with α-tocopherol-stabilized, PVP-enriched membrane, and link the results to the level of platelet loss during dialysis as a maker of biocompatibility. Method Six synthetic, PVP containing, dialyzers (FX CorAL, FX CorDiax [Fresenius Medical Care]; Polyflux, THERANOVA [Baxter]; ELISIO [Nipro]; xevonta [B. Braun]) were investigated in the present study. The content of PVP on blood-side surface was determined with X-ray photoelectron spectroscopy (XPS). The amount of elutable PVP was measured photometrically after 5h recirculation. The level of platelet loss was evaluated in an ex vivo recirculation model with human blood. Results Highest PVP content on the blood-side surface was found for the polysulfone-based FX CorAL (26.3%), while the polyethersulfone-based THERANOVA (15.6%) had the lowest PVP content. Elution of PVP was highest for the autoclave steam sterilized THERANOVA (9.1 mg/1.6m² dialyzer) and Polyflux (9.0 mg/1.6m² dialyzer), while the lowest PVP elution was found for the INLINE steam sterilized FX CorAL and FX CorDiax (< 0.5 mg/1.6m² dialyzer, for both). Highest platelet loss was found for xevonta (+164.4% compared to the reference) and the lowest for the FX CorAL (-225.2%) among the polysulfone-based dialyzers; among the polyethersulfone-based dialyzers, THERANOVA (+95.5%) had the highest and ELISIO (-52.1%) the lowest platelet loss. Conclusion PVP content and elution differs between commercially available dialyzers and was found to be linked to the membrane material and sterilization method. The amount of non-eluted PVP on the blood-side surface may be an important determinant for the hemocompatibility of dialyzers.