Definition of Tension Pneumothorax

Fig 1: Tension pneumothorax

This is an expanding pneumothorax that increasingly limits ventilation and venous return. It is not an on/off phenomenon, rather a continuum.

So even impressive expansion (see image), may be well tolerated in young individuals with no comorbidities and no other injuries. In fact it may be tolerated so well that you may miss the clinical diagnosis.

Given that the expansion is dynamic, be vigilant in patients with a chest x-ray proven small pneumothorax in whom you elect not to insert a chest drain.