[Enoxaparin in the prevention of thrombosis of extracorporeal circulation during dialysis of patients with chronic renal failure]

Enoxaparin. A reappraisal of its pharmacology and clinical applications in the prevention and treatment of thromboembolic disease

Enoxaparin (enoxaparin sodium) is a low molecular weight derivative of unfractionated heparin which has been evaluated for the treatment and prevention of thromboembolic disease. Since a previous review in Drugs, well controlled clinical trials have confirmed the effectiveness of enoxaparin as prophylaxis in patients with a high risk for deep venous thrombosis (DVT), i.e. those undergoing hip or knee replacement surgery. Enoxaparin 30mg twice daily, initiated postoperatively, offers an overall balance of prophylactic efficacy and haemorrhagic tolerability which is superior to that of unfractionated heparin. In comparative clinical trials, this dosage demonstrated either improved efficacy and a similar haemorrhagic profile, or a similar degree of efficacy with a lower rate of haemorrhagic events, compared with unfractionated heparin 5000IU 3 times daily. Limited data indicate that an enoxaparin regimen of 40mg once daily, starting preoperatively, is more effective than unfractionated heparin in patients undergoing hip replacement and has a comparable haemorrhagic profile. In patients with a moderate risk for DVT, enoxaparin is similar to unfractionated heparin in both efficacy and haemorrhagic profile, while preliminary investigations have demonstrated the utility of enoxaparin in the prevention of DVT in elderly, nonsurgical patients. Enoxaparin may also be useful for the treatment of existing DVT and as an anticoagulant in haemodialysis. Thus, enoxaparin is an effective form of prophylaxis for thromboembolic disease in moderate to high risk surgical situations. Recent evidence for improved efficacy, together with a similar incidence of haemorrhagic complications in most situations, may lead to enoxaparin being preferred to unfractionated heparin for the routine prevention of DVT after high risk surgery. Although detailed comparisons with other low molecular weight heparins and antithrombotic agents are required before its relative clinical utility can be fully assessed, enoxaparin is likely to play a significant role in the prophylaxis of thromboembolic disorders.

Influence of thromboembolism prophylaxis by low molecular weight heparin CY 216 (Fraxiparine) on several parameters of haemostasis in patients under dialysis and receiving either unfractionated heparin or CY 216

The hemorrhagic risk of an association of the low molecular weight (LMWH), Fraxiparine injected intravenously at the dose of 7.500 AXalCU or of unfractionated heparin (UFH) injected intravenously at the usual dose used during hemodialysis (3.750 +/- 1.280 IU + 1.000 IU after 2 hours of dialysis) to the subcutaneous administration once daily of a thromboembolism preventive dose of Fraxiparine (7.500 AXalCU) was evaluated on the modification of the following hemostasis parameters: thrombin time, activated partial thromboplastin time (APTT), anti Xa activity, in 13 uremic patients on hemodialysis. The association of intravenous and subcutaneous Fraxiparine prevented efficiently the clotting of the extracorporeal circulation without inducing a detectable antithrombinic activity. In contrast, the association of I.V. UFH to subcutaneous Fraxiparine induced a significant increase of the thrombin time and of the APTT, so explained by the activity of UFH. It is concluded that subcutaneous Fraxiparine at the thromboembolism preventive dose can be associated as well to I.V. Fraxiparine as to UFH without increasing the potential hemorrhagic risk. Nevertheless the association of SC and IV Fraxiparine 7.500 AXalC u seems preferable to the association of SC Fraxiparine with UFH.