[Control of low-dose heparin therapy using photometry to detect biologically active heparin]

The low-dose heparin prophylaxis depends upon a low-level activation of antithrombin III to prevent thrombin generation. For the routine regiment, the application of 5000 units twice daily seems sufficient to reduce fatal lung embolism. By comparing three commercially available heparins (Thrombophob, Thrombo-Vetren, Heparin-Dihydergot) the effectiveness of the so-called low-dose heparin application was controlled with a chromogenic substrate assay (Coatest, Kabivitrum). Only twice-daily Heparin-Dihydergot resulted in an average heparin level of 0.12 +/- 0.78 m/ml plasma, which was sufficient to provide an effective thrombosis prophylaxis.