Pneumomediastinum caused by foreign body aspiration in children.

In a retrospective review of 155 children with tracheobronchial foreign body aspiration (FBA), there were ten patients who had pneumomediastinum (PM) on an initial chest radiograph. Nine of ten presented with PM and one patient had PM noted after bronchoscopy. In a child less than two years of age with no history of trauma, the radiographic finding of PM should prompt further investigation for FBA.