6533b850fe1ef96bd12a857c

RESEARCH PRODUCT

Laboratory control of minimal heparinization during haemodialysis in patients with a risk of haemorrhage

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Abstract For patients undergoing dialysis with a high risk of haemorrhage there is no standardized procedure for anticoagulation during extracorporeal circulation. Minimal heparinization with a dose equivalent to half that used for chronic haemodialysis was employed in 49 patients (125 haemodialyses) performed after operative interventions (83.3%), after haemorrhagic events (5.2%) and after invasive investigations (11.5%). Using a biocompatible membrane and a low molecular weight heparin (bolus dose 500-1300 U; continuous infusion 100-400 U) it was possible to complete haemodialysis in 74 cases (Group 0) without clots appearing in the venous bubble trap of the tubing system. In 30 cases (Group 1) only small clots were detected at the end of haemodialysis, and in 13 cases (Group 2) larger clots (exceeding a diameter of 1 cm) were found. In eight cases (Group 3) partial or complete clot formation occurred in the tubing. No haemorrhagic complications were observed. Anti-Xa activity, thrombin-antithrombin III complex (TAT) and D-dimer were determined before haemodialysis, 2 h after the start of haemodialysis and on completion of the procedure. The anti-Xa activities ranged between < 0.2 and 0.56 U/ml. In contrast, at 2 h there were significant differences (P < 0.05) in the TAT concentrations between Group 0 and the other groups, as well as between Group 1 and Group 2 and 3. Significant differences (P < 0.05) in D-dimer levels occurred only at the end of haemodialysis. Minimal heparinization in haemodialysis is a practicable alternative in patients with a high risk of haemorrhage and extended coagulation monitoring is helpful in adjusting heparin dosage.