Bronchoscopy
Encyclopedia
Bronchoscopy is a technique
of visualizing the inside of the airway
s 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, tumor
s, 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.
, performed the first bronchoscopy in 1897. From then until the 1970s, rigid bronchoscopes were used exclusively. Killian used rigid bronchoscopy to remove a pork bone. The procedure was done in an awake patient using topical cocaine as a local anesthetic.
An American, Chevalier Jackson
, refined the rigid bronchoscope in the 1920s, using this rigid tube to visually inspect the trachea and mainstem bronchi.
A Japanese, Shigeto Ikeda
, invented the flexible bronchoscope in 1966. 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. More recently, fiberoptic scopes have been replaced by bronchoscopes with a charge coupled device (CCD) video chip located at their distal extremity.
Massive hemoptysis, defined as loss of >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.
or video camera at the opposite end. Using Bowden cable
s 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 lobe or segment 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.
, or other location with resources for the management of airway emergencies. 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 anesthetise the mucous membrane
s 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. 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
). 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.
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 will be hospitalized if there occurs any bleeding, air leakage (pneumothorax
), or respiratory distress
.
s or damage the vocal cords, the risk of bronchoscopy is limited. Complications from fiberoptic bronchoscopy remain extremely low. 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 membrane
s of the airways.
Medical procedure
A medical procedure is a course of action intended to achieve a result in the care of persons with health problems.A medical procedure with the intention of determining, measuring or diagnosing a patient condition or parameter is also called a medical test...
of visualizing the inside of the airway
Airway
The pulmonary airway comprises those parts of the respiratory system through which air flows, conceptually beginning at the nose and mouth, and terminating in the alveoli...
s 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, tumor
Tumor
A tumor or tumour is commonly used as a synonym for a neoplasm that appears enlarged in size. Tumor is not synonymous with cancer...
s, or inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
. 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.
History
A German, Gustav KillianGustav Killian
Gustav Killian was a German laryngologist, born in Mainz, and educated at the University of Freiburg-im-Breisgau. He made revolutionary advances in the diagnosis and treatment of affections of the infralaryngeal passages, especially in the diagnosis and removal of foreign bodies in the bronchial...
, performed the first bronchoscopy in 1897. From then until the 1970s, rigid bronchoscopes were used exclusively. Killian used rigid bronchoscopy to remove a pork bone. The procedure was done in an awake patient using topical cocaine as a local anesthetic.
An American, Chevalier Jackson
Chevalier Jackson
Chevalier Jackson was a laryngologist.Jackson was born in Pittsburgh, Pennsylvania. He went to school at the Western University of Pennsylvania from 1879 to 1883, and received his MD from Jefferson Medical College. He also studied laryngology in England.His work reduced the risks involved in a...
, refined the rigid bronchoscope in the 1920s, using this rigid tube to visually inspect the trachea and mainstem bronchi.
A Japanese, Shigeto Ikeda
Shigeto Ikeda
was a Japanese physician, regarded as the "father" of fiberoptic bronchoscopy.He graduated from Keio University School of Medicine in 1952 and joined the Thoracic Surgery department. In 1966, he developed the first flexible bronchoscope in conjunction with Machida Endoscope Co. Ltd and Olympus...
, invented the flexible bronchoscope in 1966. 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. More recently, fiberoptic scopes have been replaced by bronchoscopes with a charge coupled device (CCD) video chip located at their distal extremity.
Rigid
Rigid bronchoscopy is used for retrieving foreign objects.Massive hemoptysis, defined as loss of >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.
Flexible (fiberoptic)
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 eyepieceEyepiece
An eyepiece, or ocular lens, is a type of lens that is attached to a variety of optical devices such as telescopes and microscopes. It is so named because it is usually the lens that is closest to the eye when someone looks through the device. The objective lens or mirror collects light and brings...
or video camera at the opposite end. Using Bowden cable
Bowden cable
A Bowden cable is a type of flexible cable used to transmit mechanical force or energy by the movement of an inner cable relative to a hollow outer cable housing...
s 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 lobe or segment 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.
Diagnostic
- To view abnormalities of the airwayAirwayThe pulmonary airway comprises those parts of the respiratory system through which air flows, conceptually beginning at the nose and mouth, and terminating in the alveoli...
- To obtain tissueBiological tissueTissue is a cellular organizational level intermediate between cells and a complete organism. A tissue is an ensemble of cells, not necessarily identical, but from the same origin, that together carry out a specific function. These are called tissues because of their identical functioning...
specimens of the lungLungThe lung is the essential respiration organ in many air-breathing animals, including most tetrapods, a few fish and a few snails. In mammals and the more complex life forms, the two lungs are located near the backbone on either side of the heart...
in a variety of disorders. Specimens may be taken from inside the lungs by biopsyBiopsyA biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
, bronchoalveolar lavageBronchoalveolar lavageBronchoalveolar lavage is a medical procedure in which a bronchoscope is passed through the mouth or nose into the lungs and fluid is squirted into a small part of the lung and then recollected for examination. BAL is typically performed to diagnose lung disease...
, or endobronchial brushing. - To evaluate a person who has bleeding in the lungs, possible lung cancerLung cancerLung cancer is a disease characterized by uncontrolled cell growth in tissues of the lung. If left untreated, this growth can spread beyond the lung in a process called metastasis into nearby tissue and, eventually, into other parts of the body. Most cancers that start in lung, known as primary...
, a chronic coughCoughA cough is a sudden and often repetitively occurring reflex which helps to clear the large breathing passages from secretions, irritants, foreign particles and microbes...
, sarcoidosis
Therapeutic
- To remove secretions, blood, or foreign objects lodged in the airwayAirwayThe pulmonary airway comprises those parts of the respiratory system through which air flows, conceptually beginning at the nose and mouth, and terminating in the alveoli...
- LaserLaserA laser is a device that emits light through a process of optical amplification based on the stimulated emission of photons. The term "laser" originated as an acronym for Light Amplification by Stimulated Emission of Radiation...
resection of tumors or benign tracheal and bronchial strictures - StentStentIn the technical vocabulary of medicine, a stent is an artificial 'tube' inserted into a natural passage/conduit in the body to prevent, or counteract, a disease-induced, localized flow constriction. The term may also refer to a tube used to temporarily hold such a natural conduit open to allow...
insertion to palliate extrinsic compression of the tracheobronchial lumen from either malignantMalignantMalignancy is the tendency of a medical condition, especially tumors, to become progressively worse and to potentially result in death. Malignancy in cancers is characterized by anaplasia, invasiveness, and metastasis...
or benign disease processes - Bronchoscopy is also employed in percutaneous tracheostomy
- Tracheal intubationTracheal intubationTracheal intubation, usually simply referred to as intubation, is the placement of a flexible plastic or rubber tube into the trachea to maintain an open airway or to serve as a conduit through which to administer certain drugs...
of patients with difficult airways is often performed using a flexible bronchoscope
Procedure
Bronchoscopy can be performed in a special room designated for such procedures, operating room, intensive care unitIntensive Care Unit
thumb|220px|ICU roomAn intensive-care unit , critical-care unit , intensive-therapy unit/intensive-treatment unit is a specialized department in a hospital that provides intensive-care medicine...
, or other location with resources for the management of airway emergencies. The patient will often be given antianxiety and antisecretory medications (to prevent oral secretions from obstructing the view), generally atropine
Atropine
Atropine is a naturally occurring tropane alkaloid extracted from deadly nightshade , Jimson weed , mandrake and other plants of the family Solanaceae. It is a secondary metabolite of these plants and serves as a drug with a wide variety of effects...
, and sometimes an analgesic such as morphine
Morphine
Morphine is a potent opiate analgesic medication and is considered to be the prototypical opioid. It was first isolated in 1804 by Friedrich Sertürner, first distributed by same in 1817, and first commercially sold by Merck in 1827, which at the time was a single small chemists' shop. It was more...
. During the procedure, sedatives such as midazolam
Midazolam
Midazolam is a short-acting drug in the benzodiazepine class developed by Hoffmann-La Roche in the 1970s. The drug is used for treatment of acute seizures, moderate to severe insomnia, and for inducing sedation and amnesia before medical procedures. It possesses profoundly potent anxiolytic,...
or propofol
Propofol
Propofol is a short-acting, intravenously administered hypnotic agent. Its uses include the induction and maintenance of general anesthesia, sedation for mechanically ventilated adults, and procedural sedation. Propofol is also commonly used in veterinary medicine...
may be used. A local anesthetic
Local anesthetic
A local anesthetic is a drug that causes reversible local anesthesia, generally for the aim of having local analgesic effect, that is, inducing absence of pain sensation, although other local senses are often affected as well...
is often given to anesthetise the mucous membrane
Mucous membrane
The mucous membranes are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. They line cavities that are exposed to the external environment and internal organs...
s of the pharynx
Pharynx
The human pharynx is the part of the throat situated immediately posterior to the mouth and nasal cavity, and anterior to the esophagus and larynx. The human pharynx is conventionally divided into three sections: the nasopharynx , the oropharynx , and the laryngopharynx...
, larynx
Larynx
The larynx , commonly called the voice box, is an organ in the neck of amphibians, reptiles and mammals involved in breathing, sound production, and protecting the trachea against food aspiration. It manipulates pitch and volume...
, and trachea. The patient is monitored during the procedure with periodic blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
checks, continuous ECG monitoring of the heart, and pulse oximetry
Pulse oximetry
Pulse oximetry is a non-invasive method allowing the monitoring of the oxygenation of a patient's hemoglobin.A sensor is placed on a thin part of the patient's body, usually a fingertip or earlobe, or in the case of an infant, across a foot....
.
A flexible bronchoscope is inserted with the patient in a sitting or supine position. Once the bronchoscope is inserted into the upper airway
Airway
The pulmonary airway comprises those parts of the respiratory system through which air flows, conceptually beginning at the nose and mouth, and terminating in the alveoli...
, the vocal cords are inspected. The instrument is advanced to the trachea
Vertebrate trachea
In tetrapod anatomy the trachea, or windpipe, is a tube that connects the pharynx or larynx to the lungs, allowing the passage of air. It is lined with pseudostratified ciliated columnar epithelium cells with goblet cells that produce mucus...
and further down into the bronchial system and each area is inspected as the bronchoscope passes. If an abnormality is discovered, it may be sampled
Biopsy
A biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
, using a brush, a needle, or forceps. Specimen of lung tissue (transbronchial biopsy
Biopsy
A biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
) may be sampled using a real-time x-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
(fluoroscopy
Fluoroscopy
Fluoroscopy is an imaging technique commonly used by physicians to obtain real-time moving images of the internal structures of a patient through the use of a fluoroscope. In its simplest form, a fluoroscope consists of an X-ray source and fluorescent screen between which a patient is placed...
). 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.
Recovery
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 (stridorStridor
Stridor is a high pitched wheezing sound resulting from turbulent air flow in the upper airway. Stridor is a physical sign which is produced by narrow or obstructed airway path. It can be inspiratory, expiratory or biphasic . Inspiratory stridor is common...
and dyspnea
Dyspnea
Dyspnea , shortness of breath , or air hunger, is the subjective symptom of breathlessness.It is a normal symptom of heavy exertion but becomes pathological if it occurs in unexpected situations...
resulting from laryngeal edema, laryngospasm
Laryngospasm
In medicine, laryngospasm is an uncontrolled/involuntary muscular contraction of the laryngeal cords. The condition typically lasts less than 60 seconds, and causes a partial blocking of breathing in, while breathing out remains easier. It may be triggered when the vocal cords or the area of the...
, or bronchospasm
Bronchospasm
Bronchospasm or a bronchial spasm is a sudden constriction of the muscles in the walls of the bronchioles. It is caused by the release of substances from mast cells or basophils under the influence of anaphylatoxins...
). Monitoring continues until the effects of sedative drugs wear off and gag reflex
Gag reflex
The pharyngeal reflex or gag reflex is a reflex contraction of the back of the throat, evoked by touching the soft palate or sometimes the back of the tongue. It prevents something from entering the throat except as part of normal swallowing and helps prevent choking...
has returned. If the patient has had a transbronchial biopsy
Biopsy
A biopsy is a medical test involving sampling of cells or tissues for examination. It is the medical removal of tissue from a living subject to determine the presence or extent of a disease. The tissue is generally examined under a microscope by a pathologist, and can also be analyzed chemically...
, doctors may take a chest x-ray
X-ray
X-radiation is a form of electromagnetic radiation. X-rays have a wavelength in the range of 0.01 to 10 nanometers, corresponding to frequencies in the range 30 petahertz to 30 exahertz and energies in the range 120 eV to 120 keV. They are shorter in wavelength than UV rays and longer than gamma...
to rule out any air leakage in the lungs (pneumothorax
Pneumothorax
Pneumothorax is a collection of air or gas in the pleural cavity of the chest between the lung and the chest wall. It may occur spontaneously in people without chronic lung conditions as well as in those with lung disease , and many pneumothoraces occur after physical trauma to the chest, blast...
) after the procedure. The patient will be hospitalized if there occurs any bleeding, air leakage (pneumothorax
Pneumothorax
Pneumothorax is a collection of air or gas in the pleural cavity of the chest between the lung and the chest wall. It may occur spontaneously in people without chronic lung conditions as well as in those with lung disease , and many pneumothoraces occur after physical trauma to the chest, blast...
), or respiratory distress
Respiratory distress
Respiratory distress may refer to either/both:* Labored breathing, the physical presentation of respiratory distress*Shortness of breath or dyspnea - a sensation of respiratory distress-See also:*List of terms of lung size and activity...
.
Complications and Risks
Besides the risks associated with the drug used, there are also specific risks of the procedure. Although a rigid bronchoscope can scratch or tear airwayAirway
The pulmonary airway comprises those parts of the respiratory system through which air flows, conceptually beginning at the nose and mouth, and terminating in the alveoli...
s or damage the vocal cords, the risk of bronchoscopy is limited. Complications from fiberoptic bronchoscopy remain extremely low. Common complications include excessive bleeding following biopsy. A lung biopsy also may cause leakage of air, called pneumothorax
Pneumothorax
Pneumothorax is a collection of air or gas in the pleural cavity of the chest between the lung and the chest wall. It may occur spontaneously in people without chronic lung conditions as well as in those with lung disease , and many pneumothoraces occur after physical trauma to the chest, blast...
. Pneumothorax occurs in less than 1% of lung biopsy cases . Laryngospasm
Laryngospasm
In medicine, laryngospasm is an uncontrolled/involuntary muscular contraction of the laryngeal cords. The condition typically lasts less than 60 seconds, and causes a partial blocking of breathing in, while breathing out remains easier. It may be triggered when the vocal cords or the area of the...
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 membrane
Mucous membrane
The mucous membranes are linings of mostly endodermal origin, covered in epithelium, which are involved in absorption and secretion. They line cavities that are exposed to the external environment and internal organs...
s of the airways.