The purpose of this study is to compare the safety and security and efficacy of sodium enoxaparin Cristália Produtos Químicos Farmaceuticos Ltda - Endocris with Clexane (Sanofi-Aventis) to prevent Venous Thromboembolism in Patients With High-Risk to Develop Thromboembolic Disease Undergoing Geral Abdominal Surgery.

This study is a requirement of Anvisa to add a new indication for off-label drug

Inclusion Criteria:

• Men and women aged above 18 years undergoing abdominal surgery with general high risk for developing venous thromboembolism;
• Who have provided their consent by signing the consent form.

Exclusion Criteria:

• Clinical evidence of Venous thromboembolism (VTE) in the selection;

• treatment requirement with anticoagulant Low Molecular Weight Heparin, Unfracted Heparin, oral anticoagulant

• suspicion or history of coagulumpathia

• Heparin, enoxaparin allergy or hypersensitiviy known to heparin, enoxaparin, but not restrict to thrombocytopenia and/or induce thombose by heparin ou enoxaparin (thrombocytopenia induce by heparin [TIH], thrombocytopenia associate with heparin [TAH] or thrombotic thrombocytopenia syndrome induce by heparin [STTIH]

• Active bleeding that can be increased by enoxaparin.

• Previous history of known intracranial hemorrhage

• Artery-venous malformation or a suspicion or known cerebral aneurism

• Spinal, Epidural ou lumbar puncture analgesia in the last 24 hours previous of the first dose of the administration of the enoxaparin.

• erosive diseases of the digestive tract especially gastroduodenal

• Uncontrolled hypertension (systolic blood pressure [BP]> 180mmHg or diastolic BP> 100 mm Hg) at randomization or clinical hypertensive urgency;

• bacterial endocarditis

• heart valve prosthesis

• characterized by severe renal insufficiency creatinine clearance <30 ml / min

• Intra-arterial thrombolic therapy

• Thrombolic therapy within 24 hours.

• Low Molecular Weight Heparin or Unfraction Heparin treatment with prophylactic dose over 48 hours before surgery or oral anticoagulant within 5 days before surgery

• disturbance of consciousness and coma

• Less than 6 months of expectative time life

• Chemical dependency

• Patient with anesthetic risk ASA III or ASA IV

• morbid obesity with Body Mass Index ≥ 40

• Chronic use of corticosteroids

• History of allergy to Unfraction Heparin, Low molecular weight heparin or pork products.

• History of severe allergic episode, systemic anaphylaxis, or major urticarial disease Steven-Johnson

• Participation in another clinical study within 12 months prior to inclusion

• Potentially fertile woman without β-HCG negative harvested until 48 hours before operation or not using acceptable contraception for participation in this study

• Changes the security checks up to 48 h before randomization:

  • Hemoglobin <10 mg / dL;
  • ALT or AST ≥ 2.5 times ULN;
  • Platelet count <100.000/mL;
  • INR ≥ 1.5;

• Any condition which in the opinion of the investigator, could lead to increased risk for the patient or who makes it inappropriate for this study.