Emergency Medical Technician (EMT) Basic Certification Practice Exam

What is a likely cause of a pneumothorax?

1. Fluid accumulation in the lungs

2. A rupture in the lung allowing air into the pleural cavity

3. Excessive fluid in the pleural space

4. Infection causing lung consolidation

The correct answer is: A rupture in the lung allowing air into the pleural cavity

A pneumothorax occurs when air enters the pleural cavity, the space between the lung and the chest wall. This condition is often caused by a rupture in the lung tissue, which allows air to escape from the lung into this space. Such ruptures can result from various factors, including trauma, certain medical procedures, or spontaneously without obvious cause, particularly in individuals with pre-existing lung conditions. The other choices refer to different pathological conditions that do not directly lead to a pneumothorax. Fluid accumulation in the lungs typically refers to pulmonary edema, whereas excessive fluid in the pleural space is indicative of pleural effusion. Both scenarios involve fluid rather than air and do not cause the collapse of the lung that defines a pneumothorax. Infection causing lung consolidation refers to inflammation of lung tissue due to infections, such as pneumonia, which may lead to symptoms similar to a pneumothorax but is distinct in pathology. Thus, the rupture in the lung allowing air into the pleural cavity is specifically what generates the pneumothorax.