Answer 3:
I would consider give full-dose anticoagulation because she has high risks of recurrence DVT. The risks are Age>50 and unprovoked isolated distal DVT. The flight to Korea impose risk of VTE during the flight although the duration is 4-5 hours (moderately long).
The choice of full dose anticoagulation eg. Warfarin preceded by LMWH, apixaban, dabigatran, endoxaban and rivaroxaban.
I will also recommended wearing elastic stockings,exercise every 2 hours, stay hydrated, avoid coffee and alcohol, quit smoking and follow up venous ultrasound to minor progression of thrombosis.
Answer 2:
As the patient presents with clinical signs and symptoms of DVT, high pretest probability of DVT (high D dimer) but the Wells score was only 3 (clinical symptoms), the venous ultrasound should be performed to rule out DVT.
The venous ultrasound revealed an isolated distal DVT. In addition, the pulmonary ultrasound should be considered if there is high risk pulmonary embolism although not present in this case.
The duration of anticoagulant depends on the risk of recurrence. High risk the patient should be treated with anticoagulation for 3 months where as low risk can be either US surveillance or anticoagulation for 4-6 weeks. (Ref: ESC 2018)
I would perform lab work up for cancer, predisposing diseases eg IBD or thrombophilia for risk assessment.
1.symptoms: swelling legs, Hx of long standing period (risk factor),
Sign: PE:RR 25, thickness with hyperpigmentation at both legs without pitting edema
Lab: high level D-Dimer