The correct answer is A. Pulmonary embolism.

This patient presents with a classic triad suggestive of pulmonary embolism (PE):

Acute dyspnea

Hypotension

Unilateral leg swelling (right leg)

In pregnancy, patients are at increased risk for deep vein thrombosis (DVT) due to:

Hypercoagulable state

Venous stasis

Vascular changes

A clot from the leg (DVT) can dislodge and travel to the lungs, causing a pulmonary embolism.

Why A is correct (Pulmonary embolism):

NREMT-aligned medical guidance emphasizes:

“Pulmonary embolism should be suspected in patients with sudden dyspnea and signs of DVT.”

“Unilateral leg swelling is a key indicator of possible deep vein thrombosis.”

Hypotension suggests a massive PE, which is life-threatening.

Why the other options are incorrect:

B. Congestive heart failure: Typically presents with bilateral edema and gradual onset dyspnea, not sudden symptoms with unilateral leg swelling.

C. Ruptured ectopic pregnancy: Causes abdominal pain and internal bleeding, not isolated dyspnea and leg swelling.

D. Preeclampsia: Characterized by hypertension, not hypotension, and usually includes edema and proteinuria but not acute dyspnea from embolism.

Exact Extracts:

“Pulmonary embolism presents with sudden shortness of breath and may include hypotension.”

“Unilateral leg swelling suggests deep vein thrombosis.”

“Pregnancy increases the risk of thromboembolic events.”