A pneumothorax is a collection of air or gas in the pleural cavity. It typically results in atelectasis, the complete or partial collapse of the lung. One or both lungs may be affected. The condition is characterized as either spontaneous or traumatic.
FIGURE. Pneumothorax. (From Thomas, CL [ed]: Taber’s Cyclopedic Medical Dictionary, ed 21. FA Davis, Philadelphia, 2009, p 1817, with permission.)
Spontaneous pneumothorax is caused by the rupturing of a small bleb, commonly called a blister, along the surface of the lung. What causes these blebs to form is not known, but they tend to form near the apex (bottom tip) of each lung. Changes in atmospheric pressure (flying, scuba diving, mountain climbing) can put individuals at risk. Smoking marijuana is a risk factor when individuals inhale deeply, then slowly breathe out against partially closed lips, forcing the marijuana smoke deeper into the lungs. Pneumothorax also may be econdary to other lung diseases, such as asthma, emphysema, lung abscess, or lung cancer. Traumatic pneumothorax may result from inserting a central venous line, from thoracic surgery, or from penetrating chest trauma, such as a knife wound or fractured rib. A perforated esophagus or use of mechanical ventilators also can cause pneumothorax. This disorder is further classified as open or closed. In open pneumothorax, air flows between the pleural space and the outside of the body. In closed pneumothorax, air reaches the pleural space directly from the lung.
Signs and Symptoms
Classic symptoms include sudden, sharp pleuritic pain that worsens with chest movement, coughing, or breathing. There may be shortness of breath and cyanosis. In moderate to severe pneumothorax, there may also be profound respiratory distress accompanied by pallor, weak and rapid pulse, and anxiety.
Physical examination may reveal asymmetric expansion of the chest during inspiration. Auscultation typically reveals diminished breath sounds on the affected side. A chest x-ray usually provides confirmation, showing air in the pleural space. A CT scan may be ordered, and blood tests can reveal the amount of oxygen in the blood.
In spontaneous pneumothorax with no signs of increased pleural pressure or dyspnea, or in which the lung collapse is less than 20%, the treatment of choice is bed rest and careful monitoring of vital signs. In traumatic pneumothorax, a chest tube is inserted for drainage and to allow the collapsed lung to expand. A thoracoscopy procedure allows a surgeon to place a fiberscope into a tube between the ribs and surgical instruments into another tube to close the leak. Small incisions are made, and a tiny video camera is used to guide the surgery. In this procedure, two or three tubes are placed between the ribs under general anesthesia. Rarely, when this is not successful, a surgical procedure with an incision in the wall of the chest (thoracotomy) and surgical excision of a portion of the pleura (pleurectomy) may be necessary.
No significant complementary therapy is indicated.
Reassure clients by explaining the disease process and identifying precautions to take to avoid recurrence.
The prognosis for pneumothorax is generally good with effective treatment. Spontaneous pneumothorax, however, tends to be a recurrent condition. A large pneumothorax can impair cardiac function and result in pulmonary and circulatory impairment without proper treatment.
Individuals with a history of spontaneous pneumothorax should not subject themselves to extremes of atmospheric pressure such as would be encountered by flying in a nonpressurized aircraft or during scuba diving. It is best that clients do not smoke.