Testing & Diagnosis

Medically reviewed by Varun Halani, MD · August 14, 2026

Bronchoscopy

A procedure using a thin, flexible scope passed through the nose or mouth to directly view the airways and collect samples from the lungs.

In short

Bronchoscopy is a procedure in which a physician passes a thin, flexible, lighted scope through the nose or mouth and down into the airways to directly view the lungs' airways and, when needed, collect fluid or tissue samples. It is most often performed with sedation, takes roughly 30 to 60 minutes, and is commonly used to evaluate an abnormal imaging finding, unexplained cough, suspected infection, or possible interstitial lung disease.

At a Glance

What It Is

A thin, flexible scope passed through the nose or mouth to directly visualize the airways and, when needed, collect samples.

Why It Is Ordered

To evaluate an abnormal chest imaging finding, unexplained chronic cough, hemoglobin-tinged sputum, suspected infection, or possible interstitial lung disease.

What to Expect

Sedation with fasting beforehand, a 30 to 60 minute procedure, and a period of monitoring afterward before discharge.

What Results May Mean

Fluid and tissue samples are sent for laboratory analysis, and results are reviewed together with imaging and clinical history, often over several days.

  • Bronchoscopy uses a thin, flexible scope passed through the nose or mouth to directly examine the airways and, when needed, collect fluid or tissue samples.
  • Common reasons for bronchoscopy include an abnormal finding on chest imaging, unexplained chronic cough, hemoptysis, suspected airway infection, and evaluation of possible interstitial lung disease.
  • Most bronchoscopies are performed with moderate sedation, so patients need to fast beforehand and arrange a ride home afterward.
  • Sampling techniques during bronchoscopy can include bronchoalveolar lavage (washing and collecting airway fluid), brushings, and biopsy of airway or lung tissue.
  • A sore throat, mild hoarseness, and temporary cough are common and expected after the procedure and typically resolve within a day or two.
  • Bronchoscopy also has therapeutic uses, such as clearing mucus or a foreign object obstructing an airway, in addition to its diagnostic role.
  • Results from samples collected during bronchoscopy, particularly cultures and pathology, often take several days to return and are interpreted alongside imaging and clinical findings.

Bronchoscopy is a procedure that lets a physician look directly inside the airways of the lungs and, when needed, collect samples from them. A thin, flexible, lighted scope is passed through the nose or mouth, down through the throat, and into the airways, giving a direct view that imaging alone cannot provide. It is one of the more involved tests used in pulmonary evaluation, and understanding what it involves can make the idea of it far less intimidating.

What Bronchoscopy Is

The Instrument

A bronchoscope is a thin, flexible tube, roughly the width of a pencil, with a light and a small camera at its tip. Most bronchoscopies performed today use this flexible scope rather than the older rigid type, which is now reserved for specific situations such as removing certain foreign objects or managing significant airway obstruction.

What It Allows

Once positioned in the airways, the scope transmits a live video image, allowing the physician to directly inspect the lining of the trachea (windpipe) and the branching airways beyond it. Small working channels within the scope also allow instruments to be passed through it to collect fluid or tissue samples without a separate incision.

Why Bronchoscopy Is Ordered

Bronchoscopy is used across a range of diagnostic and, less commonly, therapeutic situations.

Common Reasons Bronchoscopy Is Ordered

Abnormal Imaging Finding

A nodule, mass, or other abnormality identified on a chest CT sometimes needs direct airway evaluation or tissue sampling to characterize it further.

Unexplained Chronic Cough

A persistent cough that has not been explained by initial evaluation may prompt a direct look at the airways.

Coughing Up Blood

Hemoptysis, or blood-tinged sputum, is a common reason to look directly at the airways for a source.

Suspected Infection

Fluid samples collected from deep within the lungs can identify infections that are difficult to diagnose from sputum alone.

Suspected Interstitial Lung Disease

Fluid and sometimes tissue samples can support the diagnosis of certain forms of interstitial lung disease.

Suspected Tumor

Tissue sampling through bronchoscopy can help establish a tissue diagnosis when a lung tumor is suspected.

Bronchoscopy is frequently part of the evaluation for a lung nodule identified on imaging, for chronic cough that has not resolved with initial treatment, or for suspected idiopathic pulmonary fibrosis or another interstitial lung disease, where fluid and tissue findings can support a diagnosis alongside imaging and pulmonary function testing. It is also used less commonly for therapeutic purposes, such as removing mucus that is obstructing an airway.

What Happens During the Procedure

The Bronchoscopy Sequence

  1. 01Sedation and NumbingAn IV is placed for sedation, and a local anesthetic is applied to the nose or mouth and throat to reduce discomfort and the gag reflex.
  2. 02Scope InsertionThe flexible scope is gently passed through the nose or mouth, down through the vocal cords, and into the trachea and airways.
  3. 03Direct VisualizationThe physician examines the lining of the airways for abnormalities such as inflammation, narrowing, or a visible mass.
  4. 04Sample CollectionDepending on the reason for the procedure, samples may be collected by bronchoalveolar lavage, brushing, or biopsy of airway or lung tissue.
  5. 05Scope RemovalOnce the examination and any sampling are complete, the scope is withdrawn and you are moved to a recovery area for monitoring.

The procedure itself typically takes about 30 to 60 minutes, though total time in the procedure area, including preparation and recovery, is longer. Most bronchoscopies are performed with moderate sedation given through an IV, which relaxes you and commonly results in little or no memory of the procedure while you continue to breathe on your own. Certain situations call for general anesthesia instead, and your care team will discuss which approach applies to you.

Sampling Techniques Explained

Bronchoalveolar Lavage

Bronchoalveolar lavage, often shortened to BAL, involves instilling a small amount of sterile saline through the scope into a section of the lung and then gently suctioning it back out. The recovered fluid carries cells, proteins, and any microorganisms present in that part of the lung, and it can be analyzed for infection, inflammation, or abnormal cell patterns. BAL is a common component when evaluating suspected infection or interstitial lung disease.

Brushing and Biopsy

A small brush can be passed through the scope to gently collect cells from the surface of an airway or visible abnormality. Biopsy involves using tiny forceps passed through the scope to collect a small piece of tissue, either from the airway lining itself or, in the case of transbronchial biopsy, from deeper lung tissue reached through the airway wall. Biopsy samples are sent for pathology review and, when infection is a concern, for culture.

Preparing for Your Procedure

Because sedation is typically involved, you will be asked to fast, avoiding food and most liquids, for several hours beforehand, generally overnight or as specifically instructed by the office scheduling your procedure. You will receive guidance about which of your regular medications to take on the day of the procedure and which to hold, particularly blood thinners or certain diabetes medications, since these can affect bleeding risk or need adjustment around fasting. You will need to arrange for someone to drive you home afterward, since sedation impairs your ability to drive safely for the rest of the day.

What to Expect Afterward

After the scope is removed, you are monitored in a recovery area until the sedation wears off and the numbing effect on your throat has resolved, generally about an hour. You should not eat or drink anything until your throat sensation has returned to normal, to avoid choking or accidentally inhaling food or liquid.

A sore or scratchy throat, mild hoarseness, and a temporary cough are common and expected in the day or two afterward. Some patients notice a small amount of blood-tinged mucus if a biopsy was taken, which is usually minor and resolves quickly. A low-grade fever the evening of the procedure can occur, particularly after bronchoalveolar lavage, and is usually not a sign of infection on its own, though your physician’s office can advise you on when a fever or other symptom warrants a call.

Understanding the Risks

Bronchoscopy is generally well tolerated, and serious complications are uncommon, but it is a procedure that involves sedation and instrumentation of the airways, and it carries real risks worth understanding rather than minimizing.

Risks to Be Aware Of

Sore Throat and Cough

Common and expected, usually resolving within a day or two without specific treatment.

Bleeding

More likely when a biopsy is taken. Most bleeding is minor and self-limited, though your physician monitors for it closely, especially after transbronchial biopsy.

Pneumothorax

A collapsed lung is an uncommon but recognized risk specifically associated with transbronchial biopsy, where tissue is sampled from deeper in the lung through the airway wall.

Sedation-Related Effects

Reactions to sedation and a temporary drop in oxygen levels during the procedure are possible, which is why you are closely monitored with continuous oxygen and heart rate tracking throughout.

Your physician will review your individual risk factors, including other medical conditions and medications, before the procedure and can answer specific questions about how these risks apply to your situation.

Results and Follow-Up

Some information from bronchoscopy is available right away: the physician can describe what the airways looked like and whether any visible abnormality was seen. Laboratory results take longer. Basic fluid analysis may be available within a day or two, while cultures and detailed pathology review of biopsy tissue often take several days to a week or more, since some laboratory processes, including certain cultures, require time to grow and identify organisms.

Your physician will review these results together with your imaging studies, symptoms, and overall clinical picture, typically at a follow-up visit or by phone once everything has returned. If a biopsy was taken for a suspected tumor or to help diagnose interstitial lung disease, the pathology findings are often discussed as part of a broader evaluation that may include imaging review, and next steps depend on what is found. For a fuller picture of how imaging and bronchoscopy findings fit together in evaluating scarring lung disease, see pulmonary fibrosis treatment.

Bronchoscopy is one tool among several used in pulmonary evaluation, and it is not the right test for every situation. Whether it is recommended for you depends on your specific symptoms, imaging findings, and the questions your physician is trying to answer, and it is always reasonable to ask why a bronchoscopy is being suggested and what your physician expects to learn from it.

What is a bronchoscopy?

A bronchoscopy is a procedure in which a physician passes a thin, flexible, lighted scope through the nose or mouth, down through the throat, and into the airways of the lungs. It allows direct visualization of the airways and, when needed, collection of fluid or tissue samples for laboratory analysis.

Why would I need a bronchoscopy?

Bronchoscopy is commonly ordered to evaluate an abnormal finding on chest imaging such as a nodule or mass, an unexplained chronic cough that has not responded to initial treatment, coughing up blood-tinged sputum, or suspected infection where a direct airway sample would help guide treatment. It is also used to help diagnose suspected interstitial lung disease or a suspected lung tumor, and to evaluate certain airway problems.

Will I be awake during the bronchoscopy?

Most bronchoscopies are performed with moderate sedation, sometimes described as conscious sedation, which relaxes you and often results in little or no memory of the procedure while still allowing you to breathe on your own. Some cases are performed under general anesthesia, particularly certain therapeutic procedures. Your physician's team will discuss which approach fits your situation.

How should I prepare for a bronchoscopy?

You will typically be asked to fast, avoiding food and most liquids, for several hours before the procedure because sedation is usually involved. Your physician's office will give you specific instructions about which medications to take or hold, particularly blood thinners, and you will need to arrange for someone to drive you home afterward since sedation affects your ability to drive safely.

What actually happens during the procedure?

The scope is usually passed through the nose or mouth after your throat has been numbed with a local anesthetic, and sedation is given through an IV. Once the scope is positioned in the airways, the physician directly examines the airway lining and, depending on the reason for the procedure, may collect samples using techniques such as bronchoalveolar lavage, brushings, or biopsy. The procedure itself generally takes about 30 to 60 minutes.

What is bronchoalveolar lavage?

Bronchoalveolar lavage, often called BAL, is a sampling technique performed during bronchoscopy in which a small amount of sterile saline is instilled into a section of the lung through the scope and then gently suctioned back out. The collected fluid can be analyzed for infection, inflammation, or abnormal cells, and it is a common part of evaluating suspected infection or interstitial lung disease.

Is bronchoscopy painful?

Sedation and local anesthetic to the throat mean most patients tolerate bronchoscopy well and describe it as uncomfortable rather than painful. A gagging or pressure sensation can occur as the scope passes, and some patients cough during the procedure, but significant pain is not typical.

What are the risks of bronchoscopy?

Bronchoscopy is generally well tolerated, but as with any procedure it carries some risk. A sore throat, hoarseness, and temporary cough are common and expected. Less commonly, bleeding can occur, particularly if a biopsy is taken, and a collapsed lung (pneumothorax) is a recognized risk when lung tissue biopsy is performed. Reactions to sedation and a temporary drop in oxygen levels during the procedure are also possible, which is why you are closely monitored throughout. Your physician will review your individual risk factors before the procedure.

What happens after the procedure and when will I get results?

You are monitored in a recovery area until the sedation wears off and your gag reflex, which is temporarily numbed by the local anesthetic, has returned, generally an hour or so. You should not eat or drink until your throat sensation is back to normal to avoid choking. Some samples, such as basic cell counts, may be available within a day or two, while cultures and detailed pathology results often take several days to a week or more. Your physician will discuss the findings with you at a follow-up visit.

Guidelines and Professional Societies

  1. ATSAmerican Thoracic Society — patient information series on bronchoscopy.
  2. CHESTAmerican College of Chest Physicians — guidance on flexible bronchoscopy, bronchoalveolar lavage, and transbronchial biopsy.