Abstract
The elution of polyvinylpyrrolidone (PVP) from polysulfone (PS) dialysis membranes is one of the important problems in dialysis therapy. The aim of this study was to investigate the influence of sterilization and the storage period on the elution of PVP from wet-type PS dialyzers. Seven APS-15SA(APS) dialyzers sterilized by γ-radiation and seven RENAK PS-1.6 (RENAK) dialyzers sterilized by autoclaving were used in this study. The PVP concentration(conc.) in sterile water from the blood compartment of a fresh dialyzer was measured. Then, each dialyzer was washed with 0.9% NaCl, and the amount of PVP eluted from the membrane was measured. When the blood compartment of the dialyzer was washed, the PVP conc. in the washings was measured after rinsing with 0.5 and 1.0L. The experimental use of each PS dialyzer was then performed by circulating 1.0L of NaCl solution for 4 hours at 37℃, after which the PVP conc. in the solution was measured and the amount of PVP eluted from the dialysis membrane was calculated. The conc. of PVP in the sterile water and the amount of PVP in the washings from the RENAK dialyzer were significantly greater than in these fluids from the APS dialyzer. There was no significant difference between the PVP conc. of washings obtained by rinsing with 0.5 and 1.0L. However, the amount of PVP eluted from the APS dialyzer in the circulation experiment was significantly greater than that eluted from the RENAK dialyzer. During the short-term storage of the APS dialyzer, there was a significant negative correlation between the storage period and amount of PVP eluted. With a short storage period of the APS dialyzer, only small amounts of PVP are eluted before use and by washing, so the elution of PVP from the membrane is increased by the shear stress of blood during dialysis.
