PAEA Surgery End Of Rotation (EOR) Practice Exam

What happens to the lung during inhalation in a tension pneumothorax?

1. The lung expands further

2. The lung remains the same size

3. The lung collapses further

4. The lung re-inflates

The correct answer is: The lung collapses further

In the case of tension pneumothorax, the lung collapses further during inhalation due to the increasing pressure in the pleural space. Tension pneumothorax occurs when air enters the pleural cavity and cannot escape, leading to a buildup of pressure that compresses the lung on the affected side. As a person inhales, the diaphragm moves down and the chest wall expands; however, the pressure in the pleural cavity remains higher than that in the surrounding atmospheric air. As a result, rather than expanding, the already compromised lung experiences further collapse due to the surrounding pressure. The inability to inflate the lung properly can lead to severe respiratory distress and reduced oxygenation. Understanding the mechanics of this condition emphasizes the urgency in treatment to relieve the pressure and allow re-expansion of the lung.