General Pathology USMLE Step 1 Practice Question
Two days after undergoing internal fixation of a displaced right femoral fracture sustained during a motor vehicle accident, a 34-year-old woman develops sudden shortness of breath. On examination, she is oriented only to person. Her temperature is 38.3°C (100.9°F), pulse is 122/min, respiratory rate is 31/min, and blood pressure is 152/90 mm Hg. Pulse oximetry on room air shows an oxygen saturation of 83%. There are several scattered petechiae on the anterior chest wall. Her hemoglobin concentration is 10.3 g/dL, leukocyte count is 9,500/mm³, and platelet count is 140,000/mm³. Which of the following is the most likely cause of her current condition?
Answer choices
- APlatelet thrombus obstructing the pulmonary artery
- BFat globules entering the circulationCorrect answer
- CRupture of a coronary plaque
- DDamage to the alveolar capillary endothelium
- EUncontrolled release of calcium from the sarcoplasmic reticulum
- FBacterial invasion of the pulmonary parenchyma
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