What is collapsed lung?

A collapsed lung, also known as a pneumothorax, is a condition that occurs when air enters the space between the chest wall and the lung (pleural space). As air builds up, pressure inside the pleural space increases and causes the lung to collapse. The pressure also prevents the lung from expanding when you try to inhale, causing chest pain and shortness of breath.

What are the types of collapsed lung?

  • Primary spontaneous pneumothorax: This type of collapsed lung may occur for no apparent reason, because it takes place without any underlying lung disease. Small, abnormal air sacs in the lung may rupture, releasing air. This condition can occur in otherwise healthy adults. Certain predisposing factors may increase the risk of primary spontaneous pneumothorax.
  • Secondary spontaneous pneumothorax: A collapsed lung may occur because of underlying lung diseases, such as chronic obstructive pulmonary disease, cystic fibrosis and other conditions.
  • Injury-related pneumothorax: A puncture wound to the chest, such as a gunshot or knife wound, can result in a collapsed lung. Blunt force trauma, such as a blow to the chest, or an accident that results in fractured ribs can also cause a pneumothorax.
  • Tension pneumothorax: This is a life-threatening condition that is more likely to occur with traumatic pneumothorax (after a bullet or knife wound to the chest) or in patients on mechanical ventilation (a breathing machine) than with other kinds of pneumothorax. A one-way valve mechanism prevents air from escaping the pleural cavity. When the person inhales, more air enters the pleural space, increasing pressure on the lung and heart. This can lead to respiratory compromise and to a drop in blood pressure. If the patient is not treated immediately, death can result.
  • Catamenial pneumothorax: This is an extremely rare condition that occurs only in menstruating women. The onset of the pneumothorax is usually within 72 hours before or after the menstrual cycle begins. Endometrial tissue becomes attached to the thorax, where it forms cysts. The cysts can release blood similar to the way that the lining of the uterus is shed during menstrual periods. Blood and air that enter the pleural space can cause the lung to collapse.

What causes collapsed lung?

There are many causes of collapsed lung. They are associated with the type of collapsed lung.

Factors associated with primary spontaneous pneumothorax include:

  • Cigarette smoking: Cigarette smoke can cause inflammation of the airways.
  • Family history.
  • Body type: People who are tall and thin are more likely to develop primary spontaneous pneumothorax.

Lung diseases associated with secondary spontaneous pneumothorax include:

Other factors may also cause collapsed lung. These include:

  • Injury or trauma to the chest area: Bullet or stab wounds, fractured ribs, or a blunt force injury can cause the lungs to collapse.
  • Certain medical procedures: These include procedures in which the lung may inadvertently be punctured (needle aspiration to drain fluid from the lung, biopsy or the insertion of a large intravenous catheter into a neck vein).
  • Activities in which there are sharp changes in air pressure: Flying in an airplane or deep-sea diving may result in collapsed lung.

What are the symptoms of collapsed lung?

  • Chest pain (usually sudden onset and sharp in nature).
  • Shortness of breath.
  • Skin that is bluish in color.
  • Fatigue.
  • Rapid breathing.
  • Rapid heartbeat.
  • Cough.

Last reviewed by a Cleveland Clinic medical professional on 12/01/2013.


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