摘要 |
A method for the elimination of systemic heparin or low molecular weight derivatives of heparin wherein a blood filter containing an immobilized enzyme, including enzymes such as heparinase, glucuronate-reductase, aldose-reductase, beta-glucuronidase, O-sulfatase, and N-sulfatase, or other heparin degrading or neutralizing compound is constructed for use at the effluent of an extracorporeal device. The device meets specific stringent guidelines for clinical use. The first requirement is biocompatibility of the entire system. Secondly, the system is be designed to remove clinical levels of heparin at variable flow rates, up to 4 liters blood/min for an adult to as low as 50 ml blood/min for an infant with perfusion times varying from hours up to between two and ten days for neonatal respiratory failure. Specific embodiments employing heparinase bound by tresyl chloride or CNBr techniques to reconstituted cellulose hollow fiber devices of the type used for kidney dialysis are disclosed. These include single or multistage devices suitable for heparin removal alone or in combination with dialysis or oxygenation. Also disclosed are analogous multiple membrane sheet devices. |