Pharmacologic thromboprophylaxis is usually contraindicated in the following patients
Patients with:
- Active bleeding or intracranial hemorrhage,
- A surgical procedure is planned in the immediate 6 to 12 hours (eg, spinal neuroaxial anesthesia),
- A moderate or severe coagulopathy,
- A severe bleeding diathesis or thrombocytopenia (eg, platelet count <50,000/microL or < 100,000/microL plus additional risk factors for bleeding).
References
Chest. 2012 Feb;141(2 Suppl). https://www.ncbi.nlm.nih.gov/pubmed/22315261