Pulmonary edema is best defined as?

• A. Lungs fill with fluid
• B. Infection of the lung tissue
• C. Air in the pleural space
• D. Blood clots in the pulmonary arteries

Answer: (A)

Pulmonary edema means excess fluid accumulating in the lungs, especially in the alveolar spaces and interstitium, which interferes with gas exchange. This fluid buildup is usually caused by high pressure entering the lung’s capillaries (often from left-sided heart failure) or by capillary leak. It presents with symptoms like shortness of breath and crackles on auscultation, reflecting fluid flooding the air spaces. It is not an infection (that's pneumonia), not air in the pleural space (that’s pneumothorax), and not blood clots in the pulmonary arteries (that’s pulmonary embolism). So the best definition is that the lungs fill with fluid.