Answer 2; The treatment of VTE can be divided into 3 distinct phases;
1) initial treatment phase (up to 10 days) aims for prevent propagation of DVT
2) principle treatment phase (first 3 months) to maintain therapeutic level of anticoagulant to prevent propagation of DVT and reduce risk of early recurrent VTE
3) extend treatment phase (beyond 3 months) with specific aims to reduce the long term risk of recurrent VTE, depends on underlying conditions and risk factor
In this case, the patient only has DVT and no evidence of pre-existing cancer. She should receive anticoagulant starting with unfractionated heparin (UHF) IV or Low molecular weight heparin (LMWHs)for at least 5 days and can be discontinued when INR level >2 for 2 consecutive days after starting of warfarin.
Warfarin should be prescribed for about 3 months and then consider to continue if she has any risk factors for VTE.