Abstract
Recently, a wide variety of anticoagulants have been developed and are being applied after surgical operations and for hemodialysis in patients with hemorrhagic conditions. Their use entails much difficulty, however, because of problems concerning methods of administration, cost, etc. which are yet to be resolved. We have devised and clinically tried a hemodialysis circuit involving a partial blood recirculation pathway, designed for reduction in dose or elimination of the use of heparin, with gratifying results.
The partial blood recirculation circuit consists of a bifurcation of the route on the side of venous (V) chamber, one leading to the outlet and the other for confluence with the stream just distal to the arterial (A) chamber so that the blood could flow faster, at a rate of 300-400ml/min, only within the dialysis unit to prevent blood clotting. This procedure was carried out on 49 occasions in 8 patients, 5 for low-dose heparinization and 3 for non-heparinization.
In low-heparin-dose hemodialysis a substantial heparin dose reduction in the to 300 to 1, 200 units, compared with the usual dose of 3, 000 to 10, 000 units, was achieved without any clot formation and with a practically complete return of the blood. Residual blood was as little as 1 to 4ml throughout the extracorporeal circuit including the dialyzer and recirculation pathway. In the non-heparinization hemodialysis, on the other hand, some blood clots were detected in the chambers on both the A and V sides and in the dialyzer header but virtually none within the lumina of hollow fibers. The incidence and degree of blood coagulation varied more or less with the type of dialyzer.
Hemodialysis with a partial blood recirculation circuit with low-dose or non-heparinization proved to be a safe, simple, effective procedure with only a small amount intracircuit residual blood.
