Bronchoscopy

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. 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. 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. 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. 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. 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 More recently, fiberoptic scopes have been replaced by bronchoscopes with a charge coupled device (CCD) video chip located at their distal end. The rigid bronchoscope is a hollow metal tube used for inspecting the lower airway. 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. Rigid bronchoscopy is useful for recovering inhaled foreign bodies because it allows for protection of the airway and controlling the foreign body during recovery. 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.