[The Macklin effect in the etiology for pneumediastinum in chest trauma].

This case report has the scope to review the etiology and pathophysiology of pneumomediastinum in severe blunt trauma, with a special interest to its more frequent origin: the Macklin effect. The Macklin effect is a pathophysiologic process characterized by the blunt traumatic alveolar ruptures, air dissection along bronchovascular sheaths, with the formation of blunt pulmonary interstitial emphysema, radiologic marker, until the formation of a pneumomediastinum. Its premature diagnostic acknowledgment is important in the managing of the blunt chest trauma.