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Traumatic Pneumothorax

(Collapsed Lung)


Thomas G. Weiser

, MD, MPH, Stanford University School of Medicine

Last full review/revision Jun 2020| Content last modified Jun 2020

Traumatic pneumothorax occurs when air accumulates between the chest wall and the lung because of an injury. It causes the lung to collapse partially or completely.

  • People have chest pain and sometimes feel short of breath.
  • Usually, a chest x-ray is taken.
  • Usually, a tube (thoracostomy tube) is inserted into the chest to remove the air and allow the lung to reinflate.

(See also Introduction to Chest Injuries.)

Pneumothorax may result when blunt force (such as a motor vehicle crash or fall) or a penetrating injury (such as a stab or gunshot wound) damages the lungs and/or airways. The damage allows air to leave the lung and collect between the lung and the wall of the chest. Air from the pneumothorax may also leak into the skin of the chest or neck. Many people also have blood in the pleural space (hemopneumothorax).

Pneumothorax of both lungs is very dangerous. However, most often only one lung is affected. A pneumothorax that affects only one lung is rarely dangerous unless people have a chronic lung disorder (such as asthma or COPD [chronic obstructive pulmonary disease]) or unless the pneumothorax is a tension pneumothorax or an open pneumothorax (a pneumothorax that connects to an open wound in the chest wall).


People have chest pain. Most of the pain is due to the injury that caused the pneumothorax. They may feel short of breath or breathe rapidly and feel that their heart is racing, particularly if the amount of air is large.

If air accumulates under the skin, the skin feels crackly and makes a crackling sound when touched.

Did You Know...

  • Sometimes air from a collapsed lung accumulates under the skin of the chest or neck, and the skin feels crackly when touched.


  • Chest x-ray

Doctors usually diagnose a pneumothorax based on a chest x-ray. Sometimes pneumothorax is diagnosed when CT or ultrasonography is done to diagnose other chest or abdominal injuries.


  • Usually removal of air from the pleural space

The goal of treatment is to remove the air from the pleural space and allow the lung to reinflate. Usually, a tube (thoracostomy or chest tube) is inserted into the chest between two ribs. The tube is attached to a suction device to remove the air and to allow the lung to reinflate. This procedure can be done using only a local anesthetic.

However, if the amount of air is small and causes no symptoms, doctors may not remove the air at all, because a small pneumothorax often goes away on its own. Or doctors may insert a small catheter (drain) to remove the air. Whatever the treatment, doctors typically keep the person in the hospital for observation to make sure the pneumothorax does not worsen.

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