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Bronchoscopy | |
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![]() A physician performing bronchoscopy. | |
ICD-9-CM | 33.21-33.23 |
MeSH | D001999 |
OPS-301 code | 1-62 |
MedlinePlus | 003857 |
Bronchoscopy is an endoscopic technique of visualizing the inside of the airways for diagnostic and therapeutic purposes. An instrument (bronchoscope) is inserted into the airways, usually through the nose or mouth, or occasionally through a tracheostomy. This allows the practitioner to examine the patient's airways for abnormalities such as foreign bodies, bleeding, tumors, or inflammation. Specimens may be taken from inside the lungs. The construction of bronchoscopes ranges from rigid metal tubes with attached lighting devices to flexible optical fiber instruments with realtime video equipment.
The German laryngologist Gustav Killian is attributed with performing the first bronchoscopy in 1897. [1] Killian used a rigid bronchoscope to remove a pork bone. The procedure was done in an awake patient using topical cocaine as a local anesthetic. [2] From this time until the 1970s, rigid bronchoscopes were used exclusively.
Chevalier Jackson refined the rigid bronchoscope in the 1920s, using this rigid tube to visually inspect the trachea and mainstem bronchi. [3] The British laryngologist Victor Negus, who worked with Jackson, improved the design of his endoscopes, including what came to be called the "Negus bronchoscope".
Shigeto Ikeda invented the flexible bronchoscope in 1966. [4] The flexible scope initially employed fiberoptic bundles requiring an external light source for illumination. These scopes had outside diameters of approximately 5 mm to 6 mm, with an ability to flex 180 degrees and to extend 120 degrees, allowing entry into lobar and segmental bronchi. Fiberoptic scopes have been superseded by bronchoscopes with a charge coupled device (CCD) video chip located at their distal end. [5]
The rigid bronchoscope is a hollow metal tube used for inspecting the lower airway. [6] It can be for either diagnostic or therapeutic reasons. Modern use is almost exclusively for therapeutic indications. Rigid bronchoscopy is used for retrieving foreign objects. [7] Rigid bronchoscopy is useful for recovering inhaled foreign bodies because it allows for protection of the airway and controlling the foreign body during recovery. [8]
Massive hemoptysis, defined as loss of over 600 mL of blood in 24 hours, is a medical emergency and should be addressed with initiation of intravenous fluids and examination with rigid bronchoscopy. The larger lumen of the rigid bronchoscope (versus the narrow lumen of the flexible bronchoscope) allows for therapeutic approaches such as electrocautery to help control the bleeding.
A flexible bronchoscope is longer and thinner than a rigid bronchoscope. It contains a fiberoptic system that transmits an image from the tip of the instrument to an eyepiece or video camera at the opposite end. Using Bowden cables connected to a lever at the hand piece, the tip of the instrument can be oriented, allowing the practitioner to navigate the instrument into individual lobar or segmental bronchi. Most flexible bronchoscopes also include a channel for suctioning or instrumentation, but these are significantly smaller than those in a rigid bronchoscope.
Flexible bronchoscopy causes less discomfort for the patient than rigid bronchoscopy, and the procedure can be performed easily and safely under moderate sedation. It is the technique of choice nowadays for most bronchoscopic procedures.
Flexible bronchoscopy plays an important role in the diagnosis, monitoring and therapy of certain pulmonary diseases. [9]
Interventional bronchoscopy in chronic obstructive airway inflammatory diseases including asthma and COPD has greatly evolved and show promising results for the clinical management of patients. [10]
Bronchoscopy can be performed in a special room designated for such procedures, operating room, intensive care unit, or other location with resources for the management of airway emergencies. [11]
The patient will often be given antianxiety and antisecretory medications (to prevent oral secretions from obstructing the view), generally atropine, and sometimes an analgesic such as morphine. During the procedure, sedatives such as midazolam or propofol may be used. A local anesthetic is often given to anesthetize the mucous membranes of the pharynx, larynx, and trachea. The patient is monitored during the procedure with periodic blood pressure checks, continuous ECG monitoring of the heart, and pulse oximetry.
A flexible bronchoscope is inserted with the patient in a sitting or supine position. Once the bronchoscope is inserted into the upper airway, the vocal cords are inspected. The instrument is advanced to the trachea and further down into the bronchial system and each area is inspected as the bronchoscope passes. [11]
If an abnormality is discovered, it may be sampled using a brush, a needle, or forceps. Specimen of lung tissue (transbronchial biopsy) may be sampled using a real-time X-ray (fluoroscopy) or an electromagnetic tracking system. [12] Flexible bronchoscopy can also be performed on intubated patients, such as patients in intensive care. In this case, the instrument is inserted through an adapter connected to the tracheal tube.
Rigid bronchoscopy is performed under general anesthesia. Rigid bronchoscopes are too large to allow parallel placement of other devices in the trachea; therefore the anesthesia apparatus is connected to the bronchoscope and the patient is ventilated through the bronchoscope.
Although most patients tolerate bronchoscopy well, a brief period of observation is required after the procedure. Most complications occur early and are readily apparent at the time of the procedure. The patient is assessed for respiratory difficulty (stridor and dyspnea resulting from laryngeal edema, laryngospasm, or bronchospasm). Monitoring continues until the effects of sedative drugs wear off and gag reflex has returned. If the patient has had a transbronchial biopsy, doctors may take a chest X-ray to rule out any air leakage in the lungs (pneumothorax) after the procedure. The patient may need to be hospitalized if any bleeding, pneumothorax, or respiratory distress occurs.
Besides the risks associated with the drugs used, there are also specific risks of the procedure. Although a rigid bronchoscope can scratch or tear airways or damage the vocal cords, the risk of bronchoscopy is limited. Complications from fiberoptic bronchoscopy are rare and the risks are minimized with careful technique and an ongoing dialogue with the anesthesiologist. [9] Common complications include excessive bleeding following biopsy. A lung biopsy also may cause leakage of air, called pneumothorax. Pneumothorax occurs in less than 1% of lung biopsy cases. Laryngospasm is a rare complication but may sometimes require tracheal intubation. Patients with tumors or significant bleeding may experience increased difficulty breathing after a bronchoscopic procedure, sometimes due to swelling of the mucous membranes of the airways.
The trachea, also known as the windpipe, is a cartilaginous tube that connects the larynx to the bronchi of the lungs, allowing the passage of air, and so is present in almost all animals with lungs. The trachea extends from the larynx and branches into the two primary bronchi. At the top of the trachea, the cricoid cartilage attaches it to the larynx. The trachea is formed by a number of horseshoe-shaped rings, joined together vertically by overlying ligaments, and by the trachealis muscle at their ends. The epiglottis closes the opening to the larynx during swallowing.
Tracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic tube into the trachea (windpipe) to maintain an open airway or to serve as a conduit through which to administer certain drugs. It is frequently performed in critically injured, ill, or anesthetized patients to facilitate ventilation of the lungs, including mechanical ventilation, and to prevent the possibility of asphyxiation or airway obstruction.
Tracheomalacia is a condition or incident where the cartilage that keeps the airway (trachea) open is soft such that the trachea partly collapses especially during increased airflow. This condition is most commonly seen in infants and young children. The usual symptom is stridor when a person breathes out. This is usually known as a collapsed windpipe.
Tracheotomy, or tracheostomy, is a surgical airway management procedure which consists of making an incision (cut) on the anterior aspect (front) of the neck and opening a direct airway through an incision in the trachea (windpipe). The resulting stoma (hole) can serve independently as an airway or as a site for a tracheal tube or tracheostomy tube to be inserted; this tube allows a person to breathe without the use of the nose or mouth.
Pulmonary aspiration is the entry of material such as pharyngeal secretions, food or drink, or stomach contents from the oropharynx or gastrointestinal tract, into the larynx and lower respiratory tract, the portions of the respiratory system from the trachea (windpipe) to the lungs. A person may inhale the material, or it may be delivered into the tracheobronchial tree during positive pressure ventilation. When pulmonary aspiration occurs during eating and drinking, the aspirated material is often colloquially referred to as "going down the wrong pipe".
Laryngoscopy is endoscopy of the larynx, a part of the throat. It is a medical procedure that is used to obtain a view, for example, of the vocal folds and the glottis. Laryngoscopy may be performed to facilitate tracheal intubation during general anaesthesia or cardiopulmonary resuscitation or for surgical procedures on the larynx or other parts of the upper tracheobronchial tree.
A tracheal tube is a catheter that is inserted into the trachea for the primary purpose of establishing and maintaining a patent airway and to ensure the adequate exchange of oxygen and carbon dioxide.
Airway management includes a set of maneuvers and medical procedures performed to prevent and relieve airway obstruction. This ensures an open pathway for gas exchange between a patient's lungs and the atmosphere. This is accomplished by either clearing a previously obstructed airway; or by preventing airway obstruction in cases such as anaphylaxis, the obtunded patient, or medical sedation. Airway obstruction can be caused by the tongue, foreign objects, the tissues of the airway itself, and bodily fluids such as blood and gastric contents (aspiration).
Stridor is a high-pitched extra-thoracic breath sound resulting from turbulent air flow in the larynx or lower in the bronchial tree. It is different from a stertor which is a noise originating in the pharynx.
Bronchoalveolar lavage (BAL), also known as bronchoalveolar washing, is a diagnostic method of the lower respiratory system in which a bronchoscope is passed through the mouth or nose into an appropriate airway in the lungs, with a measured amount of fluid introduced and then collected for examination. This method is typically performed to diagnose pathogenic infections of the lower respiratory airways, though it also has been shown to have utility in diagnosing interstitial lung disease. Bronchoalveolar lavage can be a more sensitive method of detection than nasal swabs in respiratory molecular diagnostics, as has been the case with SARS-CoV-2 where bronchoalveolar lavage samples detect copies of viral RNA after negative nasal swab testing.
Tracheobronchial injury is damage to the tracheobronchial tree. It can result from blunt or penetrating trauma to the neck or chest, inhalation of harmful fumes or smoke, or aspiration of liquids or objects.
A tracheotome is a medical instrument used to perform an incision in the trachea with a cutting blade operated by a powered cannula. It is often called a tracheostomy tube because once it enters the stoma in the trachea, a breathing tube is connected to a ventilator and oxygen is provided to the lungs.
Electromagnetic navigation bronchoscopy (ENB) is a medical procedure utilizing electromagnetic technology designed to localize and guide endoscopic tools or catheters through the bronchial pathways of the lung. Using a virtual, three-dimensional (3D) bronchial map from a recently computed tomography (CT) chest scan and disposable catheter set, physicians are able to navigate to a desired location within the lung to biopsy lesions, stage lymph nodes, insert markers to guide radiotherapy or guide brachytherapy catheters.
Tracheobronchomalacia (TBM) is a condition characterized by flaccidity of the tracheal support cartilage which leads to tracheal collapse. This condition can also affect the bronchi. There are two forms of this condition: primary TBM and secondary TBM. Primary TBM is congenital and starts as early as birth. It is mainly linked to genetic causes. Secondary TBM is acquired and starts in adulthood. It is mainly developed after an accident or chronic inflammation.
Foreign body aspiration occurs when a foreign body enters the airway which can cause difficulty breathing or choking. Objects may reach the respiratory tract and the digestive tract from the mouth and nose, but when an object enters the respiratory tract it is termed aspiration. The foreign body can then become lodged in the trachea or further down the respiratory tract such as in a bronchus. Regardless of the type of object, any aspiration can be a life-threatening situation and requires timely recognition and action to minimize risk of complications. While advances have been made in management of this condition leading to significantly improved clinical outcomes, there were still 2,700 deaths resulting from foreign body aspiration in 2018. Approximately one child dies every five days due to choking on food in the United States, highlighting the need for improvements in education and prevention.
A double-lumen endotracheal tube is a type of endotracheal tube which is used in tracheal intubation during thoracic surgery and other medical conditions to achieve selective, one-sided ventilation of either the right or the left lung.
An bronchial blocker is a device which can be inserted down a tracheal tube after tracheal intubation so as to block off the right or left main bronchus of the lungs in order to be able to achieve a controlled one sided ventilation of the lungs in thoracic surgery. The lung tissue distal to the obstruction will collapse, thus allowing the surgeon's view and access to relevant structures within the thoracic cavity.
Advanced airway management is the subset of airway management that involves advanced training, skill, and invasiveness. It encompasses various techniques performed to create an open or patent airway – a clear path between a patient's lungs and the outside world.
Tracheoinnominate fistula is an abnormal connection (fistula) between the innominate artery and the trachea. A TIF is a rare but life-threatening iatrogenic injury, usually the sequela of a tracheotomy.
Interventional pulmonology is a maturing medical sub-specialty from its parent specialty of pulmonary medicine. It deals specifically with minimally invasive endoscopic and percutaneous procedures for diagnosis and treatment of neoplastic as well as non-neoplastic diseases of the airways, lungs, and pleura. Many IP procedures constitute efficacious yet less invasive alternatives to thoracic surgery.