Anterior infradiaphragmatic free gas following bronchial rupture: case report and literature review.

Bronchial rupture is an uncommon injury that presents clinically and radiologically with tension or non-tension pneumothorax, pneumomediastinum and subcutaneous emphysema caused by air leak and migration of free gas. Infradiaphragmatic gas has previously been demonstrated in mechanically ventilated patients with pneumomediastinum and is secondary to passage of air via anterior and posterior trans-diaphragmatic pathways. We present a case of bronchial rupture complicated by extensive infradiaphragmatic gas following mechanical ventilation that illustrates these pathways and some of the major radiographic signs associated with this injury.