Tension pneumothorax (annotated signs)

Case contributed by Bálint Botz
Diagnosis certain


Septic, in MICU. Poor SpO2 after tracheostomy.

Patient Data

Age: 80 years
Gender: Female

Presence of a large right-sided pneumothorax and the resultant collapse of the right lung is evident.

Three worrisome features are also present:

  1. Significant mediastinal shift to the left
  2. Depressed right hemidiaphragm
  3. Widened intercostal spaces and marked asymmetric expansion of the right hemithorax

Findings are in line with a tension pneumothorax, which necessitates the insertion of a chest tube without further delay. 

Other: the tracheal tube and right IJV CVC line are in a normal position, as well as the leads of the dual chamber pacemaker. Increased interstitial markings on the left, suggestive of decompensated heart failure. Minimally displaced CT-confirmed (not shown) fractures of the anterior aspect of ribs 4-6 on the right. 

Control CXR ~1h later


The control film demonstrates the rapid improvement of all aforementioned features after the insertion of a chest tube. The position of the mediastinum and the right hemidiaphragm have normalized, as well as the volume of the right hemithorax. The right lung also shows significant reexpansion considering the short interval. A circumscribed subcutaneous emphysema has also developed around the insertion point of the chest tube. 

Annotated image

Annotated images highlighting the key CXR features of tension pneumothorax. 

Case Discussion

The case demonstrates the major imaging features of tension pneumothorax, and the rapid improvement after prompt management. It is however crucial to bear in mind that neither of these are a sine qua non of tension pneumothorax and the presence of only one or two of these signs is sufficient to raise the possibility of a tension component. 

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