Performance and Hemocompatibility of a Novel Polysulfone Dialyzer: A Randomized Controlled Trial.

Background: High-flux dialyzers effectively remove uremic toxins, are hemocompatible to minimize intradialytic humoral and cellular stimulation, and have long-term effects on patient outcomes. A new dialyzer with a modified membrane surface has been tested for performance and hemocompatibility. Methods: This multicenter, prospective, randomized, crossover study involved the application of the new polysulfone-based FX CorAL 600 (Fresenius Medical Care, Bad Homburg, Germany), the polyarylethersulfone-based Polyflux 170H (Baxter Healthcare Corporation, Deerfield, IL), and the cellulose triacetate-based SureFlux 17UX (Nipro Medical Europe, Mechelen, Belgium), for 1 week each, to assess the noninferiority of the FX CorAL 600's removal rate of ß2-microglobulin. Performance was assessed by removal rate and clearance of small- and medium-sized molecules. Hemocompatibility was assessed through markers of complement, cell activation, contact activation, and coagulation. Results: Of 70 patients, 58 composed the intention-to-treat population. The FX CorAL 600's removal rate of ß2-microglobulin was noninferior to both comparators (P<0.001 versus SureFlux 17UX; P=0.0006 versus Polyflux 170H), and superior to the SureFlux 17UX. The activation of C3a and C5a with FX CorAL 600 was significantly lower 15 minutes after treatment start than with SureFlux 17UX. The activation of sC5b-9 with FX CorAL 600 was significantly lower over the whole treatment than with SureFlux 17UX, and lower after 60 minutes than with the Polyflux 170H. The treatments with FX CorAL 600 were well tolerated. Conclusions: FX CorAL 600 efficiently removed small- and medium-sized molecules, showed a favorable hemocompatibility profile, and was associated with a low frequency of adverse events in this study, with a limited patient number and follow-up time. Further studies, with longer observation times, are warranted to provide further evidence supporting the use of the new dialyzer in a wide range of therapeutic options, and for long-term treatment of patients on hemodialysis, to minimize the potential effects on inflammatory processes.

Hemocompatibility of Polysulfone Hemodialyzers - Exploratory Studies on Impact of Treatment Modality and Dialyzer Characteristics.

Background: The hemocompatibility of dialyzers for extracorporeal kidney replacement therapy (KRT) is of importance to minimize harmful reactions between blood constituents and the membrane. We investigated in these exploratory studies the hemocompatibility profile of several types of polysulfone dialyzers. Methods: Hemocompatibility of various high-flux polysulfone dialyzers were compared in two consecutive, prospective, randomized, crossover studies, each including 24 adult patients being at least 3 months on hemodialysis (HD) or on-line hemodiafiltration (HDF). These dialyzers, differing in membrane type, fiber geometry, sterilization method, and production technology, were each applied for 1 week in HD or HDF. Hemocompatibility was assessed through markers of complement activation, cell activation, coagulation, contact activation, and immunologic reactions. Results: The patients in the two studies were on average 67±11 and 68±11 years old, 75% and 67% were male, and were on KRT for 5.4±5.0 and 4.4±3.6 years. The complement factors C3a and C5a increased early and transiently during treatment, less so with HDF than with HD, and with dialyzers combining wider inner fiber diameter (210 versus 185 µm) and advanced membrane type (Helixone plus versus Helixone). sC5b-9 increased in all study phases, reaching its highest level after 60 minutes, with lower values over the entire treatment (area under the curve) for HDF than HD, and for wider inner fiber diameter and advanced membrane type. Leukocytes decreased in the first 10 minutes, without significant differences between dialyzers. PMN elastase increased in the first hour, more so with HD than HDF. Thrombocytes decreased slightly in the first 30 minutes, with differences only between HDF and HD mode. IL-8 decreased from pre- to postdialysis, particularly on HDF. No differences were observed for kallikrein, IgE, and hsCRP. Conclusions: In these explorative studies we found indications to a comparable hemocompatibility profile of the investigated dialyzers. We observed distinctions in compounds between HDF and HD and for some dialyzer and membrane characteristics.