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Lung Disease & Respiratory Health Center

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Collapsed Lung (Pneumothorax) - Topic Overview

What is a pneumothorax?

A collapsed lung (pneumothorax) is a buildup of air in the space between the lung and the chest wall (pleural space). As the amount of air in this space increases, the pressure against the lung causes the lung to collapse. This prevents your lung from expanding properly when you try to breathe in, causing shortness of breath and chest pain.

A pneumothorax may become life-threatening if the pressure in your chest prevents the lungs from getting enough oxygen into the blood.

Recommended Related to Lung Disease/Respiratory Problems

Obstructive and Restrictive Lung Disease

Doctors may classify lung conditions as obstructive lung disease or restrictive lung disease. Obstructive lung diseases include conditions that make it hard to exhale all the air in the lungs. People with restrictive lung disease have difficulty fully expanding their lungs with air. Obstructive and restrictive lung disease share the same main symptom: shortness of breath with exertion.

Read the Obstructive and Restrictive Lung Disease article > >

What causes a pneumothorax?

A pneumothorax is usually caused by an injury to the chest, such as a broken rib or puncture wound. It may also occur suddenly without an injury.

A pneumothorax can result from damage to the lungs caused by conditions such as chronic obstructive pulmonary disease (COPD), asthma, cystic fibrosis, and pneumonia. Spontaneous pneumothorax can also occur in people who don't have lung disease. This happens when an air-filled blister (bleb) on the lung ruptures and releases air into the pleural space.

People who smoke cigarettes are much more likely to develop a pneumothorax than those who don't. Also, the more you smoke, the greater your chances are of having a pneumothorax.

What are the symptoms?

Symptoms depend on the size of the pneumothorax. In minor cases, you may not realize you have a pneumothorax. In more severe cases, symptoms will develop rapidly and may lead to shock.

Symptoms may include:

  • Shortness of breath (dyspnea), which may be mild to severe, depending on how much of the lung is collapsed.
  • Sudden, severe, and sharp chest pain on the same side as the collapsed lung.

Symptoms may become worse with altitude changes (such as flying in an airplane or going underground or underwater).

How is a pneumothorax diagnosed?

A pneumothorax usually is diagnosed through a physical exam and a chest X-ray. Your doctor may also perform blood tests to measure the level of oxygen in your blood.

A computed tomography (CT) scan or ultrasound may be needed to diagnose the severity of your condition and help plan your treatment.

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