Pulmonary Embolism USMLE Step 1 Practice Question
A 67-year-old man with metastatic prostate cancer on active chemotherapy presents with acute dyspnea and unilateral left leg swelling. Vitals show HR 108 bpm, RR 24/min, BP 138/82 mmHg, SpO2 92% on room air. CT pulmonary angiography confirms segmental pulmonary emboli in the left lower lobe. Laboratory studies reveal severe thrombocytopenia with platelets of 22,000/mm3; INR is normal. Which anticoagulation strategy is most appropriate?
Answer choices
- AObservation without anticoagulation until platelet count recovers
- BUnfractionated heparin with platelet transfusion to maintain count above 50,000Correct answer
- COral warfarin with bridging heparin
- DFull-dose enoxaparin regardless of platelet count
- EInferior vena cava filter placement without anticoagulation
- FFondaparinux monotherapy with platelet transfusion support
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