Spontaneous pneumothorax is a collection of air or gas in the chest that causes the lung to collapse (see also pneumothorax ) in the absence of a traumatic injury to the chest or lung.

Causes, incidence, and risk factors

A primary spontaneous pneumothorax occurs in a person with no known lung disease. It affects between 8,000 and 9,000 persons in the USA each year -- most often among tall, thin men between 20 and 40 years-old. Usually, the rupture of a small bleb or bullae (an air- or fluid-filled sac in the lung) causes primary spontaneous pneumothorax. Secondary spontaneous pneumothorax occurs in the setting of known lung disease, most often chronic obstructive pulmonary disease (COPD). Other lung diseases commonly associated with spontaneous pneumothorax include: tuberculosis, pneumonia, asthma, cystic fibrosis, lung cancer, and certain forms of interstitial lung disease.

Signs and tests

Listening to the chest ( auscultation ) during a physical examination reveals decreased breath sounds . Tests performed include:

A

chest X-ray

Arterial blood gases

Treatment

The objective of treatment is to remove the air from the pleural space, allowing the lung to re-expand. Small pneumothoraces may resolve on their own.

Aspiration of air, through a catheter to a vacuum bottle, may re-expand the lung. The placement of a chest tube between the ribs into the pleural space allows the evacuation of air from the pleural space, when simple aspiration is not successful, or the pneumothorax is large. Re-expansion of the lung may take several days with the chest tube left in place. Hospitalization is required for chest tube management. Surgery may be indicated for recurrent episodes. Patients should discontinue smoking and avoid high altitudes, scuba diving, or flying in unpressurized aircraft to prevent the recurrence of pneumothorax.

Expectations (prognosis)

Between 30-50% of patients with spontaneous pneumothorax experience recurrence, but there are no long-term complications following successful therapy.

Complications

Spontaneous pneumothorax can recur.

Calling your health care provider

Call your health care provider if severe shortness of breath develops. Call your health care provider if you have had a spontaneous pneumothorax and you experience the same or similar symptoms again.

Prevention

Stopping smoking will decrease the risk of developing severe lung disease that may lead to pneumothorax. Controlling certain lung disease, such as asthma, may lower the risk of pneumothorax.