Merck Manual

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Rebecca Dezube

, MD, MHS, Johns Hopkins University

Reviewed/Revised May 2021 | Modified Sep 2022
Topic Resources

Bronchoscopy is the introduction of an endoscope into the airways.

Flexible fiberoptic bronchoscopy is used for virtually all diagnostic, and most therapeutic, indications.


Flexible bronchoscopes facilitate airway visualization and documentation of findings (see table Indications for Flexible Fiberoptic Bronchoscopy Indications for Flexible Fiberoptic Bronchoscopy 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


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


Absolute contraindications to bronchoscopy include

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

  • High-grade tracheal obstruction

  • Inability to adequately oxygenate the patient during the procedure

  • Untreatable life-threatening arrhythmias

Relative contraindications to bronchoscopy include

  • Recent myocardial infarction

  • Uncooperative patient

  • 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.

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 some 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 Ultrasonography Chest imaging includes use of plain x-rays, computed tomography (CT) scanning, magnetic resonance imaging (MRI), nuclear scanning, including positron emission tomography (PET) scanning, and... read more (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.


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, or cardiac arrhythmias or arrest.

Bronchoscopy itself may cause

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

  • Hypoxemia in patients with compromised gas exchange

  • Minor laryngeal edema or injury with hoarseness

  • 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 Thoracotomy Thoracotomy is surgical opening of the chest. It is done to evaluate and treat pulmonary problems when noninvasive procedures are nondiagnostic or unlikely to be definitive. The principal indications... read more .

Drugs Mentioned In This Article

Drug Name Select Trade
Diprivan, Fresenius Propoven
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Ela-Max, GEN7T, Glydo, Gold Bond, LidaMantle, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , Lidomar , Lidomark, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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