A 58-year-old woman is evaluated in the hospital prior to being transferred from the intensive care unit to the general medical ward. She was admitted 6 days ago for a severe exacerbation of chronic obstructive pulmonary disease. Her treatment during hospitalization has included intravenous methylprednisolone, nebulized bronchodilators, and prophylactic subcutaneous unfractionated heparin. Her respiratory status has significantly improved.
Serial laboratory studies reveal the following platelet counts:
| Hospital Day | Platelet Count |
|---|---|
| Day 1 (Admission) | 310,000/mm³ |
| Day 4 | 260,000/mm³ |
| Day 6 (Today) | 145,000/mm³ |
On physical examination today, her vital signs are within normal limits. A new, demarcated, erythematous, and exquisitely tender necrotic skin lesion is noted at a recent heparin injection site on her anterior abdomen. There is no mucosal bleeding or petechiae.
Which of the following is the most appropriate next step in the management of this patient?
- AContinue unfractionated heparin and transfuse apheresis platelets
- BDiscontinue unfractionated heparin and initiate warfarin
- Discontinue unfractionated heparin and initiate argatrobanCevap
- DDiscontinue unfractionated heparin and initiate enoxaparin
- EContinue unfractionated heparin and order a serotonin release assay