Beta Blockers USMLE Step 1 Practice Question
A 63-year-old woman is hospitalized for acute pulmonary embolism with HR 118/min, BP 136/88 mmHg, RR 22/min, and SpO2 88% on room air. She is started on intravenous anticoagulation. Her aPTT, previously 28 seconds, is now 67 seconds within 2 hours. Troponin is mildly elevated. She denies previous heparin exposure. The medication works by potentiating antithrombin activity against thrombin and factor Xa. Which anticoagulant was most likely administered?
Answer choices
- AHeparinCorrect answer
- BApixaban
- CAspirin
- DWarfarin
- EClopidogrel
- FFondaparinux
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