[Minimal heparinization in dialysis patients with increased risk of bleeding]

In 78 patients (47 men, 31 women; mean age 53 [22-78] years) 174 dialyses were undertaken within one week of a bleeding episode or a diagnostic or therapeutic procedure which may cause bleeding. Minimal anticoagulation with low molecular weight heparin (LMWH) was the aim, using a biocompatible dialyser. During the dialysis coagulation was controlled by global tests (Quick value/international normalized ratio [INR], partial thromboplastin time, thrombin time, antifactor Xa activity), by molecular markers of clotting activity (thrombin-antithrombin III complex [TAT], D-dimers), as well as measurement of elastase (elastase-alpha 1-protein inhibitor complex). The LMWH dosage averaged 932 units as an initial bolus and 234 units/h as a continuous infusion. In the group of chronic dialysis patients (n = 72) this meant (standard heparin units = 2/3 LMWH units) a reduction to 45 +/- 11% from the previously used routine heparin dosage for a 4-hour dialysis. All dialyses were completed without bleeding complications. Considerable clotting formation in the extracorporeal circulation occurred in 11 dialyses (6.3%). TAT, D-dimer and elastase values proved to be suitable for determining individual clotting activity and for reducing anticoagulation to the minimum.