8. Subcutaneous emphysema

Subcutaneous emphysema develops as a result of the entry of air into the subcutaneous soft tissue of the thoracic wall. Characteristic crepitations are felt during palpation, while diagnosis can be made through a visualization of air in the subcutaneous tissue and between the muscles in a lung radiography. The amount of skin emphysema depends on the amount of air leakage from the lungs. While only skin crepitations are present in mild cases, advanced subcutaneous emphysema can be seen when there is intense air leakage and a large defect in the parietal pleura. These cases may present with swelling of the head, neck and face, and while there is no specific treatment for subcutaneous emphysema, the underlying factor should be eliminated. To reduce subcutaneous emphysema, air drainage can be performed by injecting a few largelumen wide-diameter granules subcutaneously and between the muscles of the anterior thoracic wall (Figure 3) [31, 32].

Figure 3. Thorax CT image of a patient with common subcutaneous emphysema that results from a blunt thorax trauma.
