Reverse Macklin effect.

The Macklin effect is associated with alveolar rupture causing a centripetal spread of air along the peribronchovascular interstitial sheath leading to pneumomediastinum, usually seen in ventilator-related barotrauma or blunt chest trauma. We are presenting a peculiar case of iatrogenic (post-intubational) tracheal injury with massive subcutaneous emphysema and pneumomediastinum, in whom, we suspect that the primary tracheal injury and pneumomediastinum led to dissection of air along the peribronchovascular interstitium, culminating in atelectasis of lung due to compression of the distal-most airways, with no primary parenchymal abnormality. This supposed "reversal" of pathophysiological sequence of the Macklin effect makes it a unique finding.