Which term is defined as air trapped in pleural space compressing organs?

• A. Pleural Space
• B. Tension Pneumothorax
• C. Cyanosis
• D. Hypoxemia

Answer: (B)

The concept tested is the idea of a tension pneumothorax, where air becomes trapped under pressure in the pleural space. This trapped air not only collapses the lung on the affected side but also pushes the mediastinal structures toward the opposite side. That mediastinal shift can compress the heart and great vessels, reducing venous return to the heart and leading to rapidly decreasing cardiac output, hypotension, and potential shock. Clinically this presents as severe shortness of breath with signs of respiratory distress, possible tracheal deviation away from the affected side, neck vein distention, and true emergency status requiring immediate decompression with needle thoracostomy followed by chest tube placement. The pleural space is simply the potential space around the lungs; cyanosis and hypoxemia describe oxygenation status but do not capture the pressure-driven compression characteristic of a tension pneumothorax.