PAEA Surgery End Of Rotation (EOR) Practice Exam

What occurs in a pneumothorax?

1. Fluid builds up in pleural space

2. Air builds up and lung collapses

3. Infection causes pleural thickening

4. Fluid leaks into the abdominal cavity

The correct answer is: Air builds up and lung collapses

In a pneumothorax, the key event is the accumulation of air in the pleural space, which is the area between the lung and the chest wall. This air disrupts the negative pressure necessary for lung expansion during breathing, leading to a partial or complete collapse of the lung on the affected side. This collapse occurs because the pressure outside the lung becomes equal to or greater than the pressure inside the lung, preventing it from fully expanding. The clinical implications of a pneumothorax can vary depending on the amount of air present and the degree of lung collapse. Symptoms may include sudden chest pain and shortness of breath. Diagnosis is commonly confirmed via imaging studies, such as a chest X-ray or CT scan, which will show the presence of air in the pleural space. The other options listed relate to different conditions or processes: fluid accumulation refers to pleural effusion; infection leading to pleural thickening is associated with conditions like empyema or chronic infections; and fluid leaking into the abdominal cavity points to conditions such as ascites or perforation of abdominal structures. These scenarios do not involve the influx of air into the pleural space, making them distinguishable from the mechanics of pneumothorax.