MARKERS OF HEMOSTATIC SYSTEM ACTIVATION DURING THROMBOPROPHYLAXIS WITH RECOMBINANT HIRUDIN IN TOTAL HIP-REPLACEMENT

Coagulation activation markers were studied in 148 patients undergoing total hip replacement under recombinant-hirudin (Desirudin, (TM)Revas c) prophylaxis with the aim of investigating the efficacy and safety o f this anticoagulant compared with heparin in terms of biological effe cts on coagulation variables and bleeding. Hirudin (10, 15 or 20 mg s. c. b.i.d.) or unfractionated heparin (5000 IU s.c. t.i.d.) was adminis tered immediately before surgery and continued for 8-12 days. Activate d partial thromboplastin time (aPTT), prothrombin activation fragment F-1+2 (F-1+2), thrombin-antithrombin III complexes (TAT) and D-dimer w ere measured at baseline and on postoperative days 1, 3 and 6, immedia tely before the morning injection. In comparison with baseline values, heparin had little effect on aPTT whereas the three hirudin doses pro longed aPTT significantly with no differences among the three doses. M oreover, there were no group differences in perioperative or cumulativ e blood loss or transfusion requirements. F-1+2 fragment, TAT and D-di mer plasma levels were higher than at baseline during the entire posto perative period, with different trends (F-1+2 increasing, TAT decreasi ng, D-dimer increasing, decreasing and then increasing again), but wit hout significant differences among the four treatment groups. Our find ings suggest that specific inhibition of thrombin seems a safe and eff icacious mode of blocking thrombin activity after hip surgery although it does not prevent thrombin generation.