Spontaneous cervical and mediastinal emphysema.

Subcutaneous cervical emphysema often appears as a result of surgery or trauma. However, when it occurs spontaneously, the patient may present with clinically impressive and dramatic features. The etiology is related to the rupture of terminal alveoli and dissection of air along the pulmonary vasculature. Exercise may contribute to the process by increases in intrathoracic pressure. Six cases of spontaneous cervical emphysema, all related to SCUBA diving training at a Naval facility, were recently seen at our institution. Proper management entails having a high index of suspicion for diagnosis, and then being able to identify potentially life-threatening complications.