ICU Chest Films > Air in the Chest > Pneumomediastinum

Pneumomediastinum

In the intubated patient the most likely source of air in the mediastinum is pulmonary interstitial air dissecting centripetally. Air in the mediastinum may also originate from tracheobronchial injury or air dissecting through fascial planes from the retroperitoneum. A sudden increase in thoracic pressures (e.g. blunt trauma) may also cause alveolar rupture and consequently pneumomediastinum.

Pneumomediastinum generally will not develop clinical manisfestations. However, a retrosternal crunch is sometimes auscultated.

What is the name of this sign?
Rovsing's
Hamman's
Cap'n Crunch's
Boas's

How often does pneumomediastinum cause tension pericardium?
Always
Most of the Time
Sometimes
Rarely

Pneumomediastinum often dissects up into the neck. This helps to distinguish it from pneumopericardium that, unlike pneumomediastinum, can extend inferior to the heart.