ABSTRACT
Anticoagulation effects were studied during a 4-hr hemodialysis in 6 patients using 3 different heparin regimens: I. Intravenous loading dose only; II. priming of the dialyzer and continuous infusion of heparin for 2 hr; III. intravenous loading dose and continuous infusion of heparin based on anticoagulation kinetics. In all regimens the difference of fibrinopeptide A (delta FPA) between the blood inlet and outlet of the dialyzers increased at the end of the dialyses, indicating increased fibrin formation. There was a good correlation between delta FPA and the fibrin deposition on the membranes measured with I-125-fibrinogen. delta FPA increased when heparin concentration in plasma was less than 0.5 IU/ml. The anticoagulation kinetic regimen offered no advantage over the single loading dose regimen with regard to the formation and deposition of fibrin in the dialyzers.