A 66-year-old woman experienced sudden difficulty breathing. She has a history of type 2 diabetes and deep vein thrombosis. Based on her medical history, which condition should the EMT suspect?

• A. Pulmonary embolism
• B. Congestive heart failure
• C. Severe hypoglycemia
• D. Diabetic ketoacidosis

Answer: (A)

Recognizing pulmonary embolism when a patient with a history of deep vein thrombosis develops sudden shortness of breath is the key idea. A clot can form in a leg vein, break loose, and travel to the lungs, blocking a pulmonary artery. This causes an abrupt ventilation-perfusion mismatch and rapid breathing as the body tries to compensate for reduced oxygen intake. The history of DVT makes this cause highly likely because that condition is a common source of emboli.

Congestive heart failure can cause breathing difficulty, but it typically involves signs of fluid overload (like leg swelling and edema) and a more gradual onset rather than an abrupt event from a clot. Severe hypoglycemia would present with neurologic symptoms, sweating, and altered mental status rather than sudden breathlessness. Diabetic ketoacidosis involves dehydration, polyuria, polydipsia, and a different respiratory pattern (often deep, rapid breaths) in the context of hyperglycemia. The combination of sudden dyspnea and a history of DVT most strongly points to a pulmonary embolism.