(See also Overview of Pleural and Mediastinal Disorders.)
Pneumomediastinum is air in the cavity in the central part of the chest (mediastinum).
Air can enter the mediastinum when
Most often, people have chest pain below the breastbone. The pain may be severe.
When doctors do a physical examination, they may hear a crunching or crackling noise when they listen to the chest through a stethoscope. A chest x-ray is done to confirm the diagnosis.
Usually, treatment is not necessary. However, the problem that caused pneumomediastinum may require treatment.