Which term describes lung collapse, either complete or partial?

• A. Atelectasis
• B. Pneumothorax
• C. Pulmonary edema
• D. Bronchiectasis

Answer: (A)

Atelectasis is the collapse or incomplete expansion of lung tissue. It can involve the entire lung or just a portion, resulting in reduced air in the affected area and impaired gas exchange. That direct description matches the scenario of lung tissue that has collapsed. Pneumothorax involves air in the pleural space that can cause the lung to collapse, but the specific term for the collapse of the lung tissue itself is atelectasis. Pulmonary edema is fluid buildup in the lungs, which hinders oxygen exchange but does not describe tissue collapse, and bronchiectasis is chronic widening and damage of the airways with mucus production.