Successful use of a totally heparin grafted hemodialysis system in sheep.

A total of 33 totally heparin-grafted dialysis systems using HFAK Cordis Dow Models 3 and 4 have been compared to a total of 23 nongrafted systems. The comparison of deltap, flow rate, FBVL and macroscopic inspection showed highly significant differences in favor of the heparin-grafted systems. The antithrombogenic performance of the totally heparin-grafted systems is mainly due to a small leakage of heparin during the experiments. A minimum of 1.35 X 10(-8) Gm/cm2/min of heparin is sufficient to prevent clotting at the blood-polymer interface.