[Reprocessing of capillary dialyzers]

Changes in biocompatibility parameters of the cuprophan membrane, used repeatedly after reprocessing, were assessed. It is demonstrated that when the dialyzer is applied for the second of third time, cuprophan membrane loses its ability to induce acute dialysis leucopenia, typical for first application. Repeatedly used dialyzers also failed to cause bone-marrow irritation, which at first use induced a release of juvenile neutrophils into the circulation. Prior to first application, 6 dialyzers were subjected to 3 reprocessing procedures each. In all three, the cellulose membrane did not lose its ability to cause acute leucopenia. Therefore, the chemical reagents used in reprocessing (hydrogen peroxide, sodium hypochlorite and formaldehyde) are not the cause of membrane's loss of ability to induce leucopenia. Used for 3 times running, capillary dialyzers do not essentially lose their effective capillary volume. To determine whether the dialyzer is suitable for repeated use, both visual and objective check-up of the device is necessary. Some aspects of reprocessing technology are discussed.