Progressive Care Nursing Certification (PCCN) Practice Exam

Which condition can result in a tension pneumothorax?

1. Closed pneumothorax

2. Open pneumothorax

3. Subcutaneous emphysema

4. Pneumomediastinum

The correct answer is: Closed pneumothorax

A tension pneumothorax occurs when air enters the pleural space and cannot escape, leading to increased pressure on the lungs and mediastinum. This situation can arise from a closed pneumothorax, where either a spontaneous or traumatic rupture of the lung causes air to accumulate in the pleural cavity. The valve-like effect of the pleural opening allows air in during inspiration but prevents it from escaping during expiration, causing an increase in intrathoracic pressure. In contrast, an open pneumothorax involves a direct communication between the pleural space and the external environment, which does not typically produce the same pressure dynamics as a closed pneumothorax, and although it can lead to a pneumothorax, it does not result in the tension mechanism. Subcutaneous emphysema refers to air trapped under the skin, often following chest trauma or other injuries, but it does not directly lead to tension pneumothorax. Pneumomediastinum, which is the presence of air in the mediastinal cavity, can occur due to various causes but is also not associated with the accumulation of air in the pleural space to create a tension-type scenario. Understanding these distinctions is essential for recognizing the mechanisms behind different types of