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URL of this page: https://medlineplus.gov/lab-tests/bronchoscopy-and-bronchoalveolar-lavage-bal/

Bronchoscopy and Bronchoalveolar Lavage (BAL)

What are bronchoscopy and bronchoalveolar lavage (BAL)?

A bronchoscopy is a procedure that's used to check for the cause of a lung problem. It can also be used to treat some lung diseases.

The procedure uses a bronchoscope, which is a thin, lighted tube with a tiny camera. This allows your health care provider to view images of your airways. The tube is put through your mouth or nose, down your throat, and into your airways. The tube is usually flexible but can also be rigid:

  • A flexible bronchoscope may be used to keep your airway open, suck up secretions (mucus made in your airways), or take a tissue sample (biopsy).
  • A rigid bronchoscope may be used to treat a tumor or bleeding or to remove something large stuck in your airway. It may also be used to insert a stent, which is a tiny tube placed in your airway to help you breathe.

Bronchoalveolar lavage (BAL) is a procedure that is sometimes done during a bronchoscopy. It's done to collect a sample from your lungs. It is also called bronchoalveolar washing. During the procedure, a saline solution is put through the bronchoscope to wash your airways and capture a fluid sample. The cells or bacteria in the fluid sample may be tested for infections or certain lung conditions.

Other names: flexible bronchoscopy, bronchoalveolar washing

What are they used for?

Bronchoscopy may be used to:

  • Find and treat growths or other blockages in your airways
  • Remove lung tumors
  • Control bleeding in your airway
  • Help find the cause of certain lung symptoms such as a cough that doesn't go away
  • Help guide placement of a breathing tube
  • Place medicine in your lungs to treat certain conditions
  • Help determine how severe lung cancer is (if you have already been diagnosed with it)

Bronchoscopy with BAL is used to collect tissue for testing, to help diagnose certain lung diseases such as:

Why do I need bronchoscopy and BAL?

You may need one or both tests if you have symptoms of a lung disease, such as:

You may also have one or both tests if a chest x-ray or another imaging test shows a potential problem with your lungs.

If you have an immune system disorder, you may be more likely to get certain lung problems. For example, HIV or an organ transplant can put you at higher risk for some lung infections. If your provider thinks that you may have a lung infection or other lung problem, they can use bronchoscopy, often with a BAL, to make a diagnosis. Getting an early diagnosis helps you get the correct treatment as soon as possible.

What happens during bronchoscopy and BAL?

Bronchoscopy and BAL are often done by a pulmonologist. A pulmonologist is a doctor who specializes in diagnosing and treating lung diseases.

A bronchoscopy takes about 30 to 90 minutes and usually includes the following steps:

  • You may need to remove some or all of your clothing. If so, you will be given a hospital gown.
  • You may also need to remove dentures and any removable dental appliances.
  • You will lie on a bed or table with your head raised. 
  • You may get medicine (sedative) to help you relax. The medicine will be injected into a vein or given through an IV (intravenous) line placed in your arm or hand. 
  • Your provider will spray a numbing medicine in your mouth and throat so you won’t feel any pain during the procedure.
  • Your provider will insert the bronchoscope down your throat and into your airways. The camera on the bronchoscope will take photos and connect to a video screen. 
  • As the bronchoscope is moved down, your provider can look into your airways and lungs through the bronchoscope and on the video screen.
  • Your provider may perform other treatments at this time, such as removing a tumor or clearing a blockage. 
  • At this point, you may also get a BAL.

During a BAL:

  • Your provider will put a small amount of saline through the bronchoscope.
  • After washing the airways, the saline is sucked up into the bronchoscope.
  • The saline solution will contain cells and other substances, such as bacteria, which will be taken to a lab for testing.

Will I need to do anything to prepare for the test?

You may need to fast (not eat or drink) for several hours before your procedure. Your provider will let you know how long you need to avoid food and drink.

You may need to stop taking certain medicines before this test, so tell your provider about everything you take. But don’t stop taking any medicines unless your provider tells you to.

What to expect after the test:

  • Your mouth and throat may be numb for a few hours.
  • You will have to wait to eat or drink until the numbness is gone.
  • If you’ve been given a sedative, you may be drowsy for a few hours after your procedure and should arrange to have someone take you home.
  • You may have a sore throat, cough, or hoarseness for a day or more.

Are there any risks to the test?

There is very little risk to having a bronchoscopy or a BAL. Serious complications are rare, but they may include bleeding in the airways, infection, or a pneumothorax (collapse of part of your lung).

What do the results mean?

If your bronchoscopy results were not normal, it may be a sign of lung disorder such as:

  • A blockage, growth, or tumor in the airways
  • Narrowing of part of the airways
  • Lung damage due to an immune disorder such as rheumatoid arthritis

If you had BAL and your lung sample results were not normal, it may be a sign of lung cancer or a type of infection such as:

  • Tuberculosis
  • Bacterial pneumonia
  • Fungal infection

If you have questions about your results, talk to your provider. Your provider may consider your symptoms, medical history, and the results of other tests to understand the results of your procedure.

Learn more about laboratory tests, reference ranges, and understanding results.

Is there anything else I need to know about bronchoscopy and BAL?

In addition to BAL, other procedures can be done during a bronchoscopy. These include:

  • Sputum culture. Sputum is a thick type of mucus made in your lungs. It is different than spit or saliva. A sputum culture checks for certain types of infections.
  • Laser therapy or radiation to treat tumors or cancer
  • Treatment to control bleeding in the lungs

If you had a tissue sample taken, you may also have a chest x-ray done to check for any issues.

References

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  11. Nationwide Children's [Internet]. Columbus (OH): Nationwide Children's Hospital; c2024. Bronchoscopy (Flexible Bronchoscopy and Bronchoalveolar Lavage); [cited 2024 Apr 8]; [about 4 screens.] Available from: https://www.nationwidechildrens.org/family-resources-education/health-wellness-and-safety-resources/helping-hands/bronchoscopy-flexible-bronchoscopy-and-bronchoalveolar-lavage
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The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.