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Rebecca Dezube

, MD, MHS, Johns Hopkins University

Last full review/revision Jun 2019| Content last modified Jun 2019
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Bronchoscopy is the introduction of an endoscope into the airways.

Flexible fiberoptic bronchoscopy has replaced rigid bronchoscopy for virtually all diagnostic, and most therapeutic, indications.


Rigid bronchoscopy is now used only when a wider aperture and channels are required for better visualization and instrumentation, such as when

  • Investigating vigorous pulmonary hemorrhage (in which the rigid bronchoscope can better identify the bleeding source and, with its larger suction channel, can better suction the blood and prevent asphyxiation)

  • Viewing and removing aspirated foreign bodies in young children

  • Viewing obstructive endobronchial lesions for possible laser debulking or stent placement

Flexible bronchoscopes are nearly all color video–compatible, facilitating airway visualization and documentation of findings (see table Indications for Flexible Fiberoptic Bronchoscopy).

Diagnostically, flexible fiberoptic bronchoscopy allows for

  • Direct airway visualization down to, and including, subsegmental bronchi

  • Sampling of respiratory secretions and cells via bronchial washings, brushings, and lavage of peripheral airways and alveoli

  • Biopsy of endobronchial, parenchymal, and mediastinal structures

Therapeutic uses include

  • Suctioning of retained secretions

  • Placing an endobronchial stent

  • Removing foreign objects

  • Using balloon dilation to relieve airway stenoses


Indications for Flexible Fiberoptic Bronchoscopy




Abnormal chest radiograph: To diagnose the etiology of pneumonia* in an immunocompromised patient; in an immunocompetent patient with recurrent or nonresolving disease; or in a patient with a paratracheal/mediastinal/hilar mass, parenchymal mass, or nodule, especially in a proximal lung section

Atelectasis (persistent)*

Cough (persistent, unexplained)*

Diffuse lung process (transbronchial lung biopsy)

Evaluation for rejection in lung transplant recipient

Evaluation of airway in a burn patient

Evaluation for bronchial disruption in a patient with chest trauma

Lung abscess in an edentulous patient (suspect endobronchial lesion)

Positive sputum cytology in a patient with a normal chest x-ray*

Suspected tracheoesophageal fistula

Unexplained hoarseness or vocal cord paralysis

Wheeze (localized/fixed)


Aspiration of retained secretions*, †

Bronchopulmonary lavage (pulmonary alveolar proteinosis)

Laser resection of tumor‡

Management of bronchopleural fistula

Photodynamic therapy‡

Placement of airway stent‡

Placement of endotracheal tube in a difficult situation (cervical injury, abnormal anatomy)

Removal of foreign body‡

* Flexible fiberoptic bronchoscopy is indicated only after failure of less invasive investigations and treatments.

† Flexible fiberoptic bronchoscopy is not a substitute for chest physiotherapy, bronchodilator nebulization, and nasotracheal suctioning; it should be reserved for hypoxemia (in a ventilated patient) and/or lobar atelectasis secondary to impacted secretions refractory to conventional therapy.

‡ Rigid bronchoscopy provides more control for instrumentation than flexible bronchoscopy and may be helpful.


Absolute contraindications to bronchoscopy include

  • Untreatable life-threatening arrhythmias

  • Inability to adequately oxygenate the patient during the procedure

  • Acute respiratory failure with hypercapnia (unless the patient is intubated and ventilated)

  • High-grade tracheal obstruction

Relative contraindications to bronchoscopy include

  • Uncooperative patient

  • Recent myocardial infarction

  • Uncorrectable coagulopathy

Transbronchial biopsy should be done with caution in patients with uremia, superior vena cava obstruction, or pulmonary hypertension because of increased risk of bleeding. Inspection of the airways is safe in these patients, however.


Bronchoscopy should be done only by a pulmonologist or trained surgeon in a monitored setting, typically a bronchoscopy suite, operating room, or intensive care unit (for ventilated patients).

Patients should receive nothing by mouth for at least 6 hours before bronchoscopy and have IV access, intermittent blood pressure monitoring, continuous pulse oximetry, and cardiac monitoring. Supplemental oxygen should be used.

Patients usually receive conscious sedation with short-acting benzodiazepines, opioids, or both before the procedure to decrease anxiety, discomfort, and cough. In some centers, general anesthesia (eg, deep sedation with propofol and airway control via endotracheal intubation or use of a laryngeal mask airway) is commonly used before bronchoscopy.

The pharynx and vocal cords are anesthetized with nebulized or aerosolized lidocaine (1 or 2%, to a maximum of 250 to 300 mg for a 70-kg patient). The bronchoscope is lubricated and passed either through the nostril, the mouth with use of an oral airway or bite block, or an artificial airway such as an endotracheal tube. After inspecting the nasopharynx and larynx, the clinician passes the bronchoscope through the vocal cords during inspiration, into the trachea and then further distally into the bronchi.

Several ancillary procedures can be done as needed, with or without fluoroscopic guidance:

  • Bronchial washing: Saline is injected through the bronchoscope and subsequently aspirated from the airways.

  • Bronchial brushing: A brush is advanced through the bronchoscope and used to abrade suspicious lesions to obtain cells.

  • Bronchoalveolar lavage: 50 to 200 mL of sterile saline is infused into the distal bronchoalveolar tree and subsequently suctioned out, retrieving cells, protein, and microorganisms located at the alveolar level. Local areas of pulmonary edema created by lavage may cause transient hypoxemia.

  • Transbronchial biopsy: Forceps are advanced through the bronchoscope and airway to obtain samples from one or more sites in the lung parenchyma. Transbronchial biopsy can be done without x-ray guidance, but evidence supports increased diagnostic yields and lower incidence of pneumothorax when fluoroscopic guidance is used.

  • Transbronchial needle aspiration: A retractable needle is inserted through the bronchoscope and can be used to sample enlarged mediastinal lymph nodes or masses. Endobronchial ultrasonography (EBUS) can be used to help guide the needle biopsy.

Patients are typically given supplemental oxygen and observed for 2 to 4 hours after the procedure. Return of a gag reflex and maintenance of oxygen saturation when not receiving supplemental oxygen are the two primary indices of recovery.

Standard practice is to obtain a posteroanterior chest x-ray after transbronchial lung biopsy to exclude pneumothorax.


Serious complications are uncommon; minor bleeding from a biopsy site and fever occur in 10 to 15% of patients. Patients may have an increase in cough after bronchoalveolar lavage. Rarely, topical anesthesia causes laryngospasm, bronchospasm, seizures, methemoglobinemia with refractory cyanosis, or cardiac arrhythmias or arrest.

Bronchoscopy itself may cause

  • Minor laryngeal edema or injury with hoarseness

  • Hypoxemia in patients with compromised gas exchange

  • Arrhythmias (most commonly premature atrial contractions, ventricular premature beats, or bradycardia)

  • Transmission of infection from suboptimally sterilized equipment (very rare)

Mortality is 1 to 4/10,000 patients. The elderly and patients with serious comorbidities (severe chronic obstructive pulmonary disease [COPD], coronary artery disease, pneumonia with hypoxemia, advanced cancers, mental dysfunction) are at greatest risk.

Transbronchial biopsy can cause pneumothorax (2 to 5%), significant hemorrhage (1 to 1.5%), or death (0.1%), but doing the procedure can often avoid the need for thoracotomy.

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