Conditions: Pneumothorax
Also known as collapsed lung, pneumothorax is when air leaks into the space between the ribs and the lungs.
What is a pneumothorax?
A pneumothorax is air in the chest, outside of the lung, in an area called the pleural space. Normally, the lungs stay inflated by the vacuum that exists in the pleural space, which is between the ribcage and the lungs. Without that vacuum, the lungs will collapse down to a smaller size due to the elastic nature of the lung tissue. The lungs will not add oxygen and remove carbon dioxide from the blood effectively when collapsed.
Click to enlarge.
What causes a pneumothorax?
Any leak of air into the pleural space will allow the lung to collapse. This can happen to one or both lungs. This could occur from a leak in the lung or trachea, causing a closed pneumothorax, or it could occur from a leak in the chest wall, causing an open pneumothorax. A tension pneumothorax is an extreme form of pneumothorax in which not only is the vacuum outside the lung lost, but air pressure builds up in this space. This can happen when the air leak acts like a valve, letting air into the space outside the lung with each breath, but not letting it out. That can lead to compression of the heart and the opposite lung—a situation that can cause poor blood circulation.
Pneumothorax involving the patient’s right lung (left side of screen). The yellow arrow points to air outside of the lung. Lung tissue is seen as lacy white lines on a chest x-ray, and this image shows the absence of the patient’s right lung except toward the center. The patient’s left lung, as seen by lacy white lines, extends all the way out to the ribcage, showing no left pneumothorax. Click to enlarge image.
How is pneumothorax identified?
A pneumothorax may sometimes be identified by tapping on the chest wall (called percussion) and listening to the quality of the sound produced. Listening for breath sounds is another technique. Imaging (such as with a chest x-ray) can be a more definitive way to identify the presence and measure the size of a pneumothorax. In an urgent situation, where tension pneumothorax is suspected and there is no time for imaging, a hollow needle may be placed through the chest wall to let the pressure out.
How is pneumothorax treated?
A small pneumothorax may resolve on its own without a problem. A larger pneumothorax is typically treated by placement of a chest tube, which is a tube that sucks air out of the pleural space, allowing the lung to expand.