The lungs are among the most important organs in the body. Located on either side of the chest, they not only allow us to take in oxygen from the air but also help to remove carbon dioxide, a waste product of respiration. Like most biological structures, however, they can succumb to disease. Asthma, bronchitis, cystic fibrosis, and pneumonia are all conditions that affect the lungs. When parts of the lungs’ air sacs collapse, atelectasis occurs.

What is Atelectasis?

Atelectasis is a condition in which the alveoli—the air sacs of the lungs—do not expand properly. As a result, the blood may not receive adequate oxygen—a situation that can lead to various health issues. Depending on the underlying cause, atelectasis may affect part or all of a lung. While many refer to it as a collapsed lung, the condition is not synonymous with a pneumothorax. In contrast to atelectasis, which is characterized by the collapse of one or more parts of the lung, pneumothorax refers to a state in which there is air in the pleural cavity.

Symptoms of Atelectasis

If only a few air sacs are involved, one may not have any symptoms of atelectasis. If the condition affects larger areas of the lung, however, the oxygen level in the blood may decrease, which can lead to difficulty breathing, sharp chest pains—especially when coughing or taking a deep breath—increased heart rate, rapid breathing, and blue skin.

What Causes Atelectasis?

There are two different causes of atelectasis—obstructive and non-obstructive. Obstructive atelectasis occurs when a blockage develops in the airway. As a result, air does not reach the alveoli, and they collapse. Some of the most common causes of this type include foreign objects, tumors, and mucus plugs. Non-obstructive atelectasis refers to causes unrelated to obstructions of the airway; for instance: surgery, lung scarring, or pleural effusion.

Risk Factors for Atelectasis

Some of the risk factors for atelectasis include anesthesia, prolonged bed rest, lung disease such as cystic fibrosis or asthma, use of a breathing tube, weak respiratory muscles, foreign bodies in the airway, recent abdominal surgery, heart failure, obesity, and smoking. Often, the risk of developing the condition also increases with age.

When to Seek Medical Attention

Individuals should call 911 if they are experiencing breathing difficulties accompanied by rapid breathing, severe chest pain, lightheadedness, cyanosis—a bluish discoloration of the skin due to low oxygen levels, or rapid heart rate. Depending on the severity, the patient may require a breathing machine until the lungs recover.

Diagnosing Atelectasis

Diagnosis typically begins with a physical exam, during which a physician will listen to the patient’s respiratory sounds. A chest x-ray may follow. In some cases, the doctor will perform other tests to confirm the diagnosis, such as CT scans, ultrasounds, or bronchoscopies, the last of which involves inserting a thin, flexible tube through the mouth or nose and into the lungs. A simple test called oximetry also helps determine the severity of the disease.

How to Treat Atelectasis

Mild atelectasis will typically resolve on its own. For more severe cases, however, patients may need treatment, which will differ depending on the underlying cause. For example, surgery can correct a condition due to a blockage; physicians may also prescribe medications to help loosen mucus. If the condition is due to pleural effusion or pneumothorax, the doctor may drain fluid or air from the chest using a needle or tube. Chest physiotherapy and breathing exercises may also help accelerate recovery.

How to Prevent Atelectasis

Chest surgery is one of the main causes of atelectasis. Fortunately, certain steps can prevent the complication. Specifically, individuals should stop smoking, perform deep breathing exercises, and make an effort to clear mucus from the lungs. Using a medical device called an incentive spirometer also helps prevent the condition.

Complications of Atelectasis

If left untreated, atelectasis may result in several complications. For instance, bacteria may become trapped in the lung, which can lead to pneumonia and sepsis. Bronchiectasis—abnormal enlargement of parts of the airways—pleural effusion, and hypoxemia may also occur. If the condition affects a large part of the lungs, there is a risk of respiratory failure—a potentially life-threatening condition in which the level of oxygen in the blood becomes dangerously low.

Prognosis of Atelectasis

Most individuals will recover quickly once medical professionals have addressed the underlying cause; there are rarely any long-lasting effects of atelectasis. Even if a part of the lung fails to inflate properly, the rest of the organ can compensate for the collapsed area and deliver enough oxygen to the body. Severe cases, however, may be life-threatening—especially if the individual has a preexisting condition. Those with chronic diseases that cause the condition may also require further treatment.