What does a tension pneumothorax lead to if left untreated?

A tension pneumothorax occurs when air becomes trapped in the pleural space and exerts increasing pressure on the lung and surrounding structures. If left untreated, this condition can result in the collapse of the affected lung due to the displacement of the mediastinum, including the heart and great vessels. The pressure from the trapped air compresses the lung, leading to impaired ventilation on that side and causing the lung to collapse. Additionally, the mediastinal shift can compromise venous return to the heart, leading to cardiovascular instability and potentially life-threatening complications.

The collapse of the lung and heart displacement is a direct consequence of the high pressure in the pleural cavity, which can result in decreased oxygenation and severe respiratory distress. Therefore, prompt diagnosis and treatment of a tension pneumothorax are crucial to prevent these serious outcomes. The condition necessitates urgent intervention, typically by needle decompression followed by placement of a chest tube, to relieve the pressure and restore the normal anatomy and function of the thoracic cavity.