A pneumothorax (a term for collapsed lung) occurs when air leaks into the space between your lungs and chest wall, creating pressure against the lung. Depending on the cause of the pneumothorax, your lung may only partially collapse, or it may collapse completely.

Causes

A pneumothorax can be caused by a chest injury, certain medical procedures involving your lung, lung disease, or it may occur for no obvious reason.

A small, uncomplicated pneumothorax may quickly heal on its own, but when the pneumothorax is larger, the excess air is usually removed by inserting a tube or needle between your ribs and slowly removing the air over a few days.

Symptoms

Signs and symptoms of a pneumothorax usually include:

  • Sudden, sharp chest pain on the same side as the affected lung — this pain doesn't occur in the center of your chest under the breast bone
  • Shortness of breath, which may be more or less severe, depending on how much of your lung is collapsed
  • A feeling of tightness in your chest
  • A rapid heart rate

If only a small amount of air enters the space between your lungs and your chest wall (pleural space), you may have few signs or symptoms. However, even a slightly collapsed lung is likely to cause some chest pain and some shortness of breath that slowly improves over a few hours to a day or so, even if there is no reduction in the size of the collapse.

See your doctor right away if you have sudden chest pain and trouble breathing of any kind. Many conditions other than pneumothorax can cause these symptoms, and most require an accurate diagnosis and prompt treatment. If your chest pain is severe or breathing becomes increasingly difficult, get immediate emergency care. 
 
Your lungs and chest wall are both elastic. As you inhale and exhale, your lungs recoil inward while your chest wall expands outward. The two opposing forces create a negative pressure in the space between your rib cage and lung. When air enters that space, either from inside or outside your lungs, the pressure it exerts can cause all or part of the affected lung to collapse.

There are several types of pneumothorax, defined according to what causes them:

Primary spontaneous pneumothorax: Primary spontaneous pneumothorax is thought to develop when a small air blister (bleb) on the top of the lung ruptures. Blebs are caused by a weakness in the lung tissue and can rupture from changes in air pressure when you're scuba diving, flying, mountain climbing or, according to some reports, listening to extremely loud music. Additionally, a primary spontaneous pneumothorax may occur while smoking marijuana, after a deep inhalation, followed by slow breathing out against partially closed lips that forces the smoke deeper into the lungs. But most commonly, blebs rupture for no obvious reason.
Genetic factors may play a role in primary spontaneous pneumothorax because this condition may run in families. A primary spontaneous pneumothorax is usually mild because pressure from the collapsed portion of the lung may in turn collapse the bleb.

Secondary spontaneous pneumothorax: This develops in people who already have a lung disorder, especially emphysema, which progressively damages your lungs. Other conditions that can lead to secondary spontaneous pneumothorax include tuberculosis, pneumonia, cystic fibrosis and lung cancer. In these cases, the pneumothorax occurs because the diseased lung tissue is next to the pleural space.

Secondary spontaneous pneumothorax can be more severe and even life-threatening because diseased tissue may open a wider hole, allowing more air into the pleural space than does a small, ruptured bleb. Additionally, people with lung disease already have reduced lung reserves, making any reduction in lung function more serious. A secondary spontaneous pneumothorax almost always requires chest tube drainage for treatment.

Traumatic pneumothorax: Any blunt or penetrating injury to your chest can cause lung collapse. Knife and gunshot wounds, a blow to the chest, even a deployed air bag can cause a pneumothorax. So can injuries that inadvertently occur during certain medical procedures, such as the insertion of chest tubes, cardiopulmonary resuscitation (CPR), and lung or liver biopsies.

Tension pneumothorax: The most serious type of pneumothorax, this occurs when the pressure in the pleural space is greater than the atmospheric pressure, either because air becomes trapped in the pleural space or because the entering air is from a positive-pressure mechanical ventilator. The force of the air can cause the affected lung to collapse completely. It can also push the heart toward the uncollapsed lung, compressing both it and the heart. Tension pneumothorax comes on suddenly, progresses rapidly and is fatal if not treated quickly.

Treatment

The goal in treating a pneumothorax is to relieve the pressure on your lung, allowing it to re-expand, and to prevent recurrences. The best method for achieving this depends on the severity of the lung collapse and sometimes on your overall health:

  • Observation. If your lung is less than 20 percent collapsed, your doctor may simply monitor your condition with a series of chest X-rays until the air is completely absorbed and your lung has re-expanded. Because it may take weeks for a pneumothorax to heal on its own, however, a needle or chest tube may be used to remove the air, even when the pneumothorax is small and nonthreatening.
  • Needle or chest tube insertion. When your lung has collapsed more than 20 percent, your doctor is likely to remove the air by inserting a needle or hollow tube (chest tube) into the space between your lungs and your chest wall. Chest tubes are often attached to a suction device that continuously removes air from the chest cavity and may be left in place for several hours to several days.

If you have had more than one pneumothorax, you may have additional treatments to prevent further recurrences.

A common surgical procedure is called video-assisted thoracoscopy, which uses small incisions and a tiny video camera to guide the surgery. In this procedure, two or three tubes are placed between your ribs while you're under general anesthesia. Through one of the tubes, the surgeon can observe with a fiberscope, while through the other tube, the surgeon attempts to close the air leak with surgical instruments. Rarely, when this doesn't work, a surgical procedure with an incision is necessary.

The chest tube remains in as long as necessary until the air in the pleural space is gone and doesn't recur when the chest tube is clamped and checked with an X-ray. Video-assisted thoracoscopy leads to less pain and a shorter recovery time than other types of surgery do because the chest cavity can be accessed without breaking any ribs.

Prevention

Although it's often not possible to prevent a pneumothorax, stopping smoking is an important way to reduce your risk of a first pneumothorax and avoid a recurrence.

Risk factors for pneumothorax include:

  • Gender. In general, men are far more likely to have a pneumothorax than women are, though women can develop a rare form of pneumothorax (catamenial pneumothorax) related to the menstrual cycle.
  • Smoking. This is the leading risk factor for primary spontaneous pneumothorax. The risk increases with the length of time and the number of cigarettes smoked.
  • Age. Primary spontaneous pneumothorax is most likely to occur in people between 20 and 40 years old, especially if the person is very tall and underweight.
  • Lung disease. Having another lung disease, especially emphysema, makes a collapsed lung more likely.
  • A history of pneumothorax. If you've had one pneumothorax, you're at increased risk of another, usually within one to two years of the first episode. This may occur in the same lung or the opposite lung.

 

Page Type: 

You may also be interested in: