Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at May 26, 2016

When air escapes from the lung, it can fill the pleural cavity between the lungs and the chest wall. The resulting buildup of air puts pressure on the lung and can cause the lung to collapse, preventing normal expansion during breathing. This condition is called pneumothorax and is also referred to as a collapsed lung.


Definition & Facts

Pneumothorax may be categorized as traumatic or nontraumatic/spontaneous. Nontraumatic/spontaneous pneumothorax may be categorized as either primary or secondary. Primary spontaneous pneumothorax involves a collapsed lung in the absence of lung disease where secondary spontaneous pneumothorax is a collapsed lung as a complication of preexisting lung disease.

Causes of pneumothorax include lung disease, sports injury, improper technique or accidents incurred during scuba diving or mountain climbing, and other causes, although some are unknown. Pneumothorax occurs when:

  • Free air has collected in the chest cavity, known as the thoracic cavity, causing the lung to collapse
  • The condition may be caused by injury, due to underlying disease or may occur spontaneously
  • Spontaneous pneumothorax often self-resolves
  • When lung disease or injury causes the pneumothorax, immediate medical treatment is needed
  • A chest tube may need to be inserted into the chest wall to aspirate the free air from the chest cavity

Symptoms & Complaints

Primary symptoms of pneumothorax include shortness of breath and sudden pain in the chest. These symptoms are similar to those of a variety of health issues, so it can be hard to immediately diagnose. Some other conditions with these symptoms may be life endangering, so medical treatment is advised when chest pain and breathing problems occur. Some common symptoms of pneumothorax include:

Severe pneumothorax can lead to the following symptoms:


Pneumothorax may be caused by any of the following conditions:

  • Injury to the chest, whether blunt or penetrating. Physical assaults, sports injury, car crashes and other incidents may be to blame, or medical procedures involving chest needle insertion may cause a collapsed lung. People who play hard contact sports are more likely to suffer a pneumothorax. Such sports include football and rugby, extreme activities like motocross and stunt-oriented sports. Violent fighting is a frequent cause of collapsed lungs.
  • Lung disease, due to damaged lung tissue unable to support breathing. Underlying diseases such as chronic obstructive pulmonary disease (COPD), pneumonia, and cystic fibrosis often result in pneumothorax. Congenital disorders like Marfan syndrome may also increase the risk of pneumothorax.
  • Rupture of air blisters (blebs) that develop on top of the lung.
  • Endometriosis can cause pneumothorax when endometrial cysts form within the lungs and bleed during menstruation.
  • Mechanical ventilation, when the ventilator creates an air pressure imbalance within the chest.

Risk factors for a collapsed lung include:

  • Gender, with men being more likely to have pneumothorax than women
  • Smoking, in regard to the length of time smoking has been a habit and number of cigarettes smoked each day
  • Age, with air blister rupture most often occurring in patients aged 20 to 40 years
  • Being very tall and underweight
  • Prior pneumothorax, as risk increases within the year or two following the original occurrence

Exposure to some environmental factors such as silica and other occupational breathing hazards puts people at higher risk for pneumothorax. Silicosis is a specific kind of lung disease caused by breathing in silica that leads to the scarring of lung tissue and pneumothorax.

Diagnosis & Tests

Diagnosis of pneumothorax usually occurs following a chest X-ray. CT scans may be required for more detailed imaging. The doctor will examine the patient and listen to their breathing through a stethoscope. Decreased breathing sounds or none at all on one side may indicate a collapsed lung. Low blood pressure can also be an indicator. The doctor will likely order the following tests, when pneumothorax is a possible diagnosis:

Treatment & Therapy

Pneumothorax is treated by relieving pressure on the lung to allow it to expand normally. A second objective is to prevent the collapse from recurring. How these objectives are accomplished is determined according to the severity of the pneumothorax and the patient's overall health.

Sometimes only a small portion of the lung collapses. In this type of case, the doctor may choose to observe the patient's condition using chest X-rays until the excess air is reabsorbed and the lung expands normally. Supplemental oxygen may be used to speed up the recovery process.

Other instances of pneumothorax may require needle or chest tube insertion for aspiration of the excess air. This is often the case when a larger area of the lung has collapsed. A hollow tube or needle is inserted into the air-filled space from between the patient's ribs for excess air to be pulled out. Some cases require insertion of a tube with a suction device attached, through which air will be removed until the chest cavity is clear.

When other methods like a chest tube fail, surgery may be needed to close the rupture or tear that is leaking air. This may be performed using a fiber-optic camera and very small incisions through which narrow surgical tools are inserted. The surgeon looks for the source of the air leak and closes it. Sometimes larger incisions are required for large air leaks or when there are multiple ruptures.

Prevention & Prophylaxis

Collapsed lungs, because they are often due to injury or other unexpected causes, cannot be prevented. When scuba diving or mountain climbing, observing proper procedures in use of oxygen can reduce the risk of pneumothorax during these activities. Not smoking or quitting smoking can also help reduce risk of a collapsed lung.