- Age > 65 years
- Confinement to bed for more than 3 days, due to:
- Heart failure
- Exacerbated chronic obstructive pulmonary disease
- Acute rheumatic involvement
- Written informed consent
1. Cancer
2. Anticoagulant treatment in the previous 3 months
3. Stroke or major surgery in the previous 3 months
4. Systolic pressure >200 mmHg or diastolic pressure >120 mmHg
5. Known chronic hepatopathy
6. Active hemorrhage in any site in the previous 3 months
7. Active peptic ulcer
8. Bacterial endocarditis
9. Conditions that can increase the risk of hemorrhage
10. Known coagulation disorders
11. Hypersensitivity to heparin or HIT
12. Life expectancy of less than 3 months
13. Previous confinement to bed during more than 3 days