**4.2.3 Summary**

86 Progress in Hemodialysis – From Emergent Biotechnology to Clinical Practice

Initial level

For PES Membrane For PA membrane For PSF Membrane

Fig. 12. *Total* bilirubin (TBIL), *direct* bilirubin (DBIL), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) level changes after 4 h hemodialysis. Data are expressed

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TBIL DBIL ALT AST

We speculated that the high-flux dialysis membrane might possibly let some biocompatibility markers enter dialysis solution so that the plasma levels of these markers could provide biased information. The plasma levels of biocompatibility markers may have also been influenced by adsorption to the membrane surface (Benz et al., 2007; Gotz et al., 2008). The adsorption to the membrane was not determined in our study. However, the protein adsorption capacity was investigated, and no difference was observed. On the basis of our results, we concluded that the designed modifications of the new high-flux PES dialyzer resultED in its higher middle molecule clearance efficacy, and had an effect on thrombogenicity as assessed by platelet behavior and fibrinolysis. Although coagulation system judged by one of the evaluated parameters was slightly higher compared with the other dialyzers, it was still within the biocompatible dialyzer range. In terms of complement activation and changes in leukocyte count, the new dialyzer is also comparable with the other biocompatible dialyzers. Besides the thrombogenicity, complement activation, and WBC count changes, other issues must be considered when evaluating bio(in)compatibility

One further aspect merits consideration is that the PES membrane dialyzer series exhibits a higher permeability and thus, cytokine-inducing substances, possibly present in the dialysis fluid, might gain access to the blood stream through internal filtration (backfiltration). Therefore, investigations on the pyrogen permeability of PES membranes have been performed to the studies on the inflammatory response of the membrane. In the study, the dialysate compartment was deliberately contaminated with purified lipopolysaccharides (LPS) from Escherichia coli, as well as with LPS derived from Stenotrophomonas (Sten)

as the meansSD, n =3

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(Krieter et al., 2007; Klingel et al., 2004)

The PES hollow fiber membrane hemodialyzer was effective and safe in the therapy for uremic patients. The PES hollow fiber hemodialysis membrane could effectively remove water and waste products including not only small molecular weight solutes such as urea and creatinine but also "middle" molecular solute as 2-microglobulin. Slight neutropenia and platelet adhesion were observed at the initial stage of the hemodialysis and no significant difference was found in electrolyte or blood biochemistry before or after the treatment. The data indicated that the performances of PES, PSF and PA hemodialyzers in the clinical setting were comparable and the PES hemodialyzer might be better than the others. The results indicated that PES hollow fiber membrane had a potentially wide application for hemodialysis.
