Tension Pneumothorax

Excerpt

Pneumothorax is air collection in the pleural space, resulting in lung collapse from positive pleural pressure. Tension pneumothorax occurs when pleural pressure is transmitted to the mediastinum (see Image. Left-Sided Tension Pneumothorax Radiograph). This uncommon condition has a malignant course and might result in death if left untreated. Tension pneumothorax may arise in the prehospital setting, emergency department, and intensive care unit.

The thorax has 3 compartments: the right and left pulmonary cavities and the centrally located mediastinum. The pulmonary cavities are lined internally by the parietal pleura. The visceral or pulmonary pleura wraps around the lungs. The pleural cavity is the potential space between the parietal and visceral pleurae. Serous pleural fluid normally lubricates the pleural surfaces.

Diaphragmatic depression and the ribs' outward motion expand the lungs during normal inspiration. The lungs increase in size as the pleural pressure becomes slightly negative. Normal expiration occurs with diaphragmatic elevation and slight inward motion of the ribs. The positive pleural pressure pushes the air out of the lungs.

Pleural disruption can introduce air into the pleural cavity. Positive pleural pressure can cause lung contraction, reducing oxygenation and ventilation in the affected lung. High positive pleural pressure can also compress the mediastinum and its structures, notably the heart, great blood vessels, and the trachea. Tension pneumothorax arises, compromising respiration, venous return, and cardiac output.

Early recognition and management of tension pneumothorax saves lives. Rapid administration of emergency thoracic decompression is a skill all healthcare professionals must have.