What Is Atelectasis?

Atelectasis is seen on imaging studies of the chest like X-rays and CT.  Atelectasis is collapse of the lung or a part of it.  The lung becomes airless and loses volume.

What is atelectasis of the lung?

Atelectasis is when the lung or a portion of it becomes collapsed.  The lung loses air and collapses.  This can involve an entire lung or a tiny portion of it.   There are many different causes, some of which are serious.

Atelectasis signs and symptoms

You can have difficulty breathing especially if you already have lung disease.  Other symptoms can be cough, wheezing, and some others depending on the cause of the atelectasis.

Atelectasis on chest X-ray

Atelectasis on chest X-ray will appear as a white area of lung with loss of volume.  The normally dark air filled lung will become white and lose volume.  It loses volume because it is not filled with air.

What causes atelectasis in the lungs?

Atelectasis can be caused by anything that causes the lung to collapse.  This can be something that presses on the lung from the outside like fluid, a mass, bleeding, infection and scarring of the lung.

Atelectasis can also be caused by blockage of the bronchi or airway.  This can be from an inhaled foreign body, mucus, or tumor.

Atelectasis can also occur when you are not taking deep breaths. This is common after surgery and trauma to the ribs.

Is atelectasis dangerous?

Atelectasis has many causes some of which are dangerous.  Tumors, infections, bleeding, can all be dangerous and need to be promptly treated.

What is bibasilar atelectasis?

Bibasilar atelectasis means that the atelectasis involves the lower lobes on both sides or the bottom most part of the lungs.  We call the bottom most part of the lung the lung base.

What is dependent atelectasis?

Dependent atelectasis is when the lung collapses along the most gravity dependent portion of the chest.   This is usually the part of the lungs closest to the back when the patient is laying on their back.  This is commonly seen in patients who have no symptoms.

What is subsegmental atelectasis?

Subsegmental atelectasis means that a small portion (less then a segment) of the lung has collapsed.  This is often asymptomatic given the small size.  For more detailed information read the following article: what is subsegmental atelectasis.

What are the three types of atelectasis?

Resorptive (obstructive) atelectasis

This is when the airway is blocked by either a tumor, foreign body or mucus.  Air can not get past the blocked airway and the lung collapses.

Compressive atelectasis

This occurs when something presses on the lung and forces air out of it.  This can be a mass, fluid, bleeding to name some.

Adhesive atelectasis

This occurs in preterm neonates from lack of surfactant production in the lungs and subsequent collapse.

In addition to these three major types, there are others like passive (often from fluid around the lung), related to lung scarring, dependent atelectasis, and adjacent to bone spurs in the spine.

Atelectasis treatment

The treatment depends on the cause.  Mild or asymptomatic atelectasis may go away on its own.

Medications can be used to loosen mucus in the airways.

Blockages of the airways may need cancer treatments, surgery or bronchoscopy depending on the cause.

Chest physiotherapy involves deep breathing exercises.  Percussion involves tapping over the collapsed area to loosen mucus. Postural drainage means that your head is positioned lower then the chest which allows mucus to drain from the lungs.

Atelectasis of the lung: summary

Atelectasis is collapse of the lung.  This can be an entire lung or a small part of it.  The causes are varied, some of which are potentially life threatening.  Imaging studies can help determine the cause and guide treatment.