Atelectasis: Symptoms and Treatment

Medically Reviewed by Jabeen Begum, MD on April 03, 2024
Written by Frances Gatta, Matt Smith, Amy Gopal
8 min read

Atelectasis (pronounced a-teh-LEK-tuh-sis) is a lung condition that happens when your airways or the tiny sacs at the end of them don’t expand the way they should when you breathe. Because of this, a part of your lung, called a lobe, or even your whole lung could collapse.

Your lungs are where your body takes in oxygen and gets rid of carbon dioxide. When you breathe in, air flows into your windpipe, or trachea. The trachea splits into two channels called bronchi, and each bronchus goes to a lung.

Inside your lungs, those airways divide again and again into smaller tubes called bronchioles. At the end of the smallest bronchioles are tiny sacs called alveoli. Here, your blood dumps carbon dioxide and picks up fresh oxygen to carry to the cells in your body.

When you breathe in and out, your lungs inflate and deflate like balloons. But if your airways get blocked or something puts pressure on your lungs, they might not inflate the way they should. Doctors call that condition atelectasis. It can be life-threatening in small children or people who have another lung problem.

If you have atelectasis, you'll feel like you can’t get enough air. Other symptoms can include:

If you’re having trouble breathing, get medical help right away.

You may get atelectasis when your airways are physically blocked by something such as:

  • Mucus
  • An object that you accidentally inhaled
  • A tumor in your airway

Or you might get it because of outside pressure caused by things such as:

  • A tumor pressing on your airway
  • A deformed bone
  • A tight brace or body cast
  • Fluid or air between your lung and your chest wall (pleural effusion and pneumothorax)
  • Pneumonia
  • Scarred lung tissue

Atelectasis may also be a complication of conditions affecting the lungs, such as chronic obstructive pulmonary disease (COPD), acute respiratory distress syndrome (ARDS), and COVID-19.

What is the most common cause of atelectasis?

Surgery is the most common cause of atelectasis. The medication that puts you to sleep (called anesthesia) can affect how your lungs work. The surgery itself could also make it hurt to breathe deeply.

Atelectasis often happens after heart surgery with a cardiopulmonary bypass, a procedure that moves blood away from your heart and lungs.

Other factors that make you more likely to have atelectasis during and after surgery include muscle relaxants, obesity, pregnancy, poor pain management, and thoracic surgery.

Atelectasis and COVID

Atelectasis may happen if you have COVID-19 pneumonia, a lung infection caused by the SARS-CoV-2 virus. This complication may happen in up to 24% of COVID-19 pneumonia cases and is tied to worse clinical outcomes.

A 2022 case study looked at a 44-year-old person assigned male at birth with obesity who later developed atelectasis after having a moderate case of COVID. The study noted that he had other chronic illnesses and was treated with a COVID medication called remdesivir, as well as oxygen and awake self-prone positioning -- a lying face-down technique to improve breathing and oxygen flow in the body. However, the study revealed that the combination of obesity and self-prone positioning when he had COVID led to atelectasis.

Some people may be more likely than others to have atelectasis. Things that can raise your odds of getting it include:

The major types of atelectasis are:

  • Resorptive or obstructive
  • Compressive
  • Contraction

Resorptive or obstructive atelectasis. This happens if carbon dioxide and oxygen leave your alveoli and new air doesn't move in, causing your alveoli to collapse.

Obstructive atelectasis happens when something physically blocks your airway, preventing air from reaching your alveoli.

Compressive atelectasis. In this, something around your lung is pushing against it, causing it to collapse. Things that could cause the compression include tumors, fluid, air, and blood.

Contraction atelectasis. Also called cicatrization atelectasis, this happens when the tissue that makes up your lungs has scars that keep your alveoli from being able to hold as much air as they should. This scarring can happen because of certain serious lung conditions like fibrosis or tuberculosis.

Other types of atelectasis include:

Adhesive atelectasis. The fluid that lines the alveoli in your lungs has a material in it called pulmonary surfactant. It helps your lungs in several ways, including keeping the alveoli stable and able to work. However, if there's a problem with this material (like if your body doesn’t make enough of it), the alveoli can collapse. When that happens, it's called adhesive atelectasis. It can be caused by serious lung problems such as respiratory distress syndrome or a bruised lung (pulmonary contusion).

Replacement atelectasis. This type happens when a tumor fills up or replaces your alveoli in an area of your lung. This severe form can cause a complete lung collapse.

Acceleration atelectasis. When jet pilots fly straight up in the air really fast (between 5 and 9 G-forces), the acceleration can close the airways in their lungs, leading to this type of atelectasis. It can make it hard to breathe and cause chest pain and coughing.

Rounded (also called folded lung) atelectasis. This type is linked to pleural diseases, conditions that affect the thin tissue that lines your chest cavity and surrounds your lungs (the pleura). One of the most common causes is asbestosis, which occurs when you breathe in asbestos over a long period, and it damages the pleura.

Bibasilar atelectasis. This happens when the lower lobes of both of your lungs collapse.

Linear atelectasis. This is a lung collapse that takes a linear shape. It often happens when the airway is blocked. It's also called discoid, plate, or band atelectasis. In people who constantly have linear atelectasis but seem to show no symptoms, it may be an early sign of lung cancer.

Dependent atelectasis. Dependent or gravity-dependent atelectasis is a type of passive atelectasis that occurs when a person remains lying down for too long. It often happens in people who had a surgery involving general anesthesia.

If your doctor thinks you might have atelectasis, they'll probably recommend tests such as:

Atelectasis X-ray. A chest X-ray is the first test a doctor might do to confirm if you have atelectasis. In the image, a collapsed lung may look partly or completely white. Then, they might do a CT scan, which will give a more detailed picture of your lungs.

Ultrasound. An ultrasound uses sound waves to make images of your airways. It can tell your doctor more about what’s causing your symptoms.

Bronchoscopy. Your doctor uses a bronchoscope, a device that looks inside your lungs, to find any problems. A bronchoscope is a thin tube with a light and a camera that goes down your throat and into your airways.

Oximetry or blood gas test. These measure how much oxygen is getting into your blood.

Atelectasis vs. pneumothorax

Although symptoms of atelectasis and pneumothorax may look alike, they’re different conditions. Atelectasis occurs when the lung deflates, causing it to collapse. On the other hand, pneumothorax is when air seeps into the area between your lungs and chest wall, compressing your lungs and causing a partial or full collapse.

Atelectasis vs. pneumonia

Pneumonia is a respiratory infection that can cause atelectasis.

If a tumor or another health condition is causing the problem, your doctor will treat it.

Atelectasis treatments include:

  • Bronchoscopy to clear blockages like mucus
  • Medicine that you breathe in through an inhaler
  • Physiotherapy such as tapping on your chest to break up mucus, lying on one side or with your head lower than your chest to drain mucus, and exercises to help you breathe better
  • A breathing tube or continuous positive airway pressure (CPAP) machine
  • Physical activity, if possible

Your symptoms may improve even without treatment. However, your doctor has to watch your progress.

If you don’t treat atelectasis, it can lead to complications, including:

  • Pneumonia (mucus can cause an infection in your lung)
  • Respiratory failure
  • Fluid buildup
  • Low blood oxygen (if your lungs can’t inflate right, they might not be able to get enough oxygen into your blood)

Some steps may help you prevent atelectasis before and after surgery:

  • Quit smoking, ideally at least 6-8 weeks before having any kind of operation.
  • Ask your doctor about deep breathing exercises and coughing after you have surgery.
  • Talk to your doctor about a device called an incentive spirometer, which helps promote proper breathing.
  • Try to be as active as you can be after surgery.

In general, keep small objects out of reach of children so they can’t find and inhale them, which could cause obstructive atelectasis.

Your outlook depends on several factors, including the cause of your atelectasis. After treatment, a collapsed lung usually begins working normally again. But in some cases, atelectasis can cause permanent damage.

Atelectasis happens when the small sacs in your lungs (alveoli) can’t inflate properly, leading to a partial or full collapse of your lungs. It can cause distressing symptoms such as difficulty breathing, chest pain, and a fast heart rate. With the guidance of a doctor, atelectasis can be treated and may even get better by itself. But if left untreated, it can lead to more health problems. Get medical help immediately if you’re having any trouble breathing, especially after surgery.

What is atelectasis, and how is it treated?

Atelectasis is a lung condition where your airways or the tiny sacs at the end of them don’t expand the way they should as you breathe, leading to a partial or full collapse of your lungs. Your treatment will depend on what's causing the condition. Options include medicine, procedures to clear blockages in the lungs, deep breathing exercises, and physiotherapy exercises that help you breathe more easily and deeply.

Should I worry about mild atelectasis?

You don’t have to worry about mild atelectasis, as it can be treated with prompt diagnosis or even go away without treatment. If you have symptoms such as trouble breathing, coughing, chest pain, a fast heart rate, and bluish skin or lips, it's important to seek medical treatment to confirm that you have atelectasis and how severe it is.

What is the best intervention for atelectasis?

The best intervention for atelectasis will depend on what’s causing it. Your doctor can tell you the best treatment for your case.