Study Evaluation of Recombinant Hirudin in Prophylaxis of Post-Operative Deep Vein Thrombosis

Inclusion Criteria: * 18 years of age or older * Body Weight \>60 kg * Patients undergoing major orthopedic operations * Patients ready to sign informed consent form (ICF) * Patients should discontinue any agents that affect haemostasis prior to the study medication use unless strictly indicated. These agents include medications such as: anticoagulants, thrombolytics, non-steroidal anti- inflammatory agents (including Ketorolac tromethamine), preparations containing aspirin, systemic salicylates, ticlopidine, dextran 40, clopidogrel, other anti-platelet agents including glycoprotein IIb/IIIa antagonists or systemic glucocorticoids. Exclusion Criteria: * Significant bleeding injury such as solid organ laceration or intracranial bleed at discretion of attending physician * Hypersensitivity to Hirudin or prior documented Allergy to its components * Pregnant or breast feeding * Hemorrhagic stroke in preceding 3 months * abnormal baseline coagulation characterized by an INR \>1.4, obtained at the discretion of the treating clinician * Required therapeutic anticoagulation for atrial fibrillation, prior VTE, or mechanical heart valve * Patients with a history of coagulation disorder * Treatment with concomitant anti-platelet agent other than aspirin 326 mg or more daily (Platelet count\< 100X109 /dl) * Active bleeding * Subjects with a life expectancy less than 1 month