FP529COMPARATIVE PERFORMANCE AND BIOCOMPATIBILITY ASSESSMENT STUDY OF A NEW HIGH-FLUX DIALYZER XEVONTA®

Abstract

Introduction and Aims: Despite significant technological progress, outcomes of hemodialysis (HD) patients remain grim. Therefore, further technological innovations are sought that would enable more efficient and safe treatment. The aim of this study was to compare a recently devised Xevonta® dialyzer with established high‐flux dialyzers. Methods: In a prospective, cross‐sectional manner, 12 long‐term HD patients were treated with Xevonta® Hi23 (B‐Braun, 2.3 m2), CorDiax FX100® (Fresenius, 2.2 m2) and Polyflux® 210H (Gambro, 2.1 m2) dialyzers. Procedure setting including heparin dose was maintained throughout the study. Dialyzer performance was evaluated both for small solutes (single‐pool KtV, URR) and middle‐molecule markers (β2‐microglobulin, 11 kDa; myoglobin, 17 kDa; retinol‐binding protein, 21 kDa; and α1‐microglobulin, 26 kDa) from pre/post dialyzer plasma concentrations along the session. Concurrently, CRP, C5a, IL6 and TNF levels were measured to assess dialyzer biocompatibility. The data (given as mean ± standard error) were corrected for ultrafiltration where appropriate and analyzed by means of factorial ANOVA models, using Bonferroni correction while p<0.05 was considered significant. Results: Both URR (74.1%±1.10, 72.0%±1.18, 72.2%±0.98, p=0.006) and KtV (1.56 ±0.055, 1.46±0.053, 1.48±0.048, p<0.001) were found higher in Xevonta compared to CorDiax and Polyflux dialyzers respectively. Plasma reduction ratio for phosphate did not differ significantly among the three dialyzers. The intradialytic decrease in β2‐microglobulin levels was significantly higher with Xevonta and CorDiax dialyzers compared to Polyflux dialyzer (19.1±1.32 mg/l, 20.4±1.82 mg/l, 16.8±1.50 mg/l; p<0.001), while plasma myoglobin decrease was higher with CorDiax versus Xevonta and Polyflux dialyzers (70.9±12.02 μg/l, 51.1±7.25 μg/l, 42.7±6.36 μg/l; p=0.0015). For higher molecular weights, no significant differences were observed. During the session, a mild but statistically significant increase in CRP (increment at 4 hours: 0.6±0.27 mg/l, 0.2±0.26 mg/l, 1.3±0.55 mg/l; p=0.035) and C5a (fold increase at 15 min: 2.1±0.59, 2.1 ±0.64, 1.9±0.23; p<0.001) levels was detected in Xevonta, CorDiax, and Polyflux dialyzers respectively. However, no significant differences among dialyzers were captured (p=0.09 and p=0.4 for CRP and C5a respectively). Using TNF and IL6, no consistent inflammatory response could have been demonstrated. Conclusions: Significant differences in clearance for both low‐ and middle‐ molecule markers were documented between Xevonta® Hi23 dialyzer and both control dialyzers (i.e. CorDiax FX100® and Polyflux® 210H). These differences can be attributed in part to different membrane permeability (as suggested by varied clearance with respect to molecular weight) but in part also to unequal membrane surface (though for all three product lines, the largest dialyzer has been chosen). Mild inflammatory response occurred during HD, without significant difference among individual dialyzers.