Which condition occurs when a clot travels to the pulmonary arteries causing sudden respiratory distress?

• A. Pulmonary edema
• B. Pulmonary embolism
• C. Anaphylaxis
• D. Delirium

Answer: (B)

When a clot travels from the veins to the lungs and lodges in the pulmonary arteries, it blocks blood flow through portions of the lung. This sudden obstruction disrupts gas exchange, causing abrupt shortness of breath and often chest pain, with signs like rapid breathing and a drop in oxygen levels. This is the scenario described by a pulmonary embolism.

Pulmonary embolism is different from other conditions that can cause breathing problems. Pulmonary edema involves fluid buildup in the lungs, typically from heart failure, and usually presents with crackles on exam and signs of fluid overload. Anaphylaxis is a severe allergic reaction that affects the airway and circulation, often with wheezing, swelling, and low blood pressure. Delirium is an acute change in mental status, not primarily a lung vascular problem.