Comparison of Two Heparin Formulations in Patients With Chronic Renal Failure.

Inclusion Criteria: 1. Research that patients agreed to participate and signed the written informed consent; 2. Patients aged over 18 years, both sexes, regardless of color or social class; 3. Patients with impaired renal function in chronic hemodialysis schedule of at least 3 times a week and giving the use of heparin in the prophylaxis of thrombosis in the system. Exclusion Criteria: 1. Hypersensitivity to heparin sodium and / or benzyl alcohol; 2. History of bleeding or disease that the change of blood coagulation could aggravate or terminate the clinical manifestations, such as tables of active peptic or gastric ulcer; 3. Severe liver disease; 4. Cancer; 5. Period of gestation; 6. Genetic abnormality of the coagulation system; 7. Multiple trauma; 8. Use of aspirin in high doses (above 200mg per day); 9. Use of glucocorticoids for at least 1 month; 10. Use of other anticoagulants; 11. Submission of a big surgery done less than 15 days; 12. History of persistent hypertension at the end of dialysis than 150/100 mmHg; 13. Indicated doses of heparin 20% above or below 150UI/kg.