5 week old ex-preterm with sudden onset of respiratory distress following intubation and insertion of a feeding tube.

A large amount of air is seen on both sides of the thin pericardium and below the heart with a small amount of air tracking along the soft tissues of the neck.  The air within the pericardial space indicates the pneumopericardium while that outside indicates the pneumomediastinum.

Also note the low-lying position of the endotracheal tube, however, the feeding tube is correctly positioned with its tip in the stomach.

Complete opacification of the both lungs is also seen in keeping with the history of respiratory distress.

Also note absence of ossification of the humeral head epiphyses in keeping with the preterm state.