Atelectasis (at-uh-LEK-tuh-sis) — a complete or partial collapse of a lung or lobe of a lung — develops when the tiny air sacs (alveoli) within the lung become deflated. It is one of the most common breathing (respiratory) complications after surgery. Atelectasis is also a possible complication of other respiratory problems, including cystic fibrosis, inhaled foreign objects, lung tumors, fluid in the lung, severe asthma and chest injuries.
The amount of lung tissue involved in atelectasis is variable, depending on the cause. Signs and symptoms of atelectasis also vary. Atelectasis can be serious because it reduces the amount of oxygen available to your body. Treatment depends on the cause and severity of the collapse.
There may be no obvious signs or symptoms of atelectasis. If you do experience signs and symptoms, they may include:
Significant atelectasis is likely to occur when you're already in a hospital. However, see your doctor right away if you have trouble breathing. Other conditions besides atelectasis can cause breathing difficulties and require an accurate diagnosis and prompt treatment. If your breathing becomes increasingly difficult, seek emergency care.
Atelectasis may be the result of a blocked airway (obstructive) or of pressure from outside the lung (nonobstructive).
Almost everyone who undergoes surgery has some atelectasis from anesthesia. Anesthesia changes the dynamics of airflow within the lungs, the absorption of gases and pressures, all of which combine to cause some degree of collapse of the tiny air sacs (alveoli) in your lungs. It is particularly prominent after heart bypass surgery.
A blockage in your air passages (bronchial tubes) can cause obstructive atelectasis. Possible causes of blockage include:
Possible causes of nonobstructive atelectasis include:
A chest X-ray usually can diagnose atelectasis. Symptoms of a respiratory infection, especially pneumonia, on a child's chest X-ray may indicate a foreign body, the most common cause of obstructive atelectasis in children.
To determine the underlying cause, your doctor may order other tests, including:
The following complications may result from atelectasis:
To decrease atelectasis risk:
Factors that increase the risk of atelectasis include: