The origins of airway management: Tools and techniques
Pioneers such as Trousseau and Trendelenburg really refined and popularized the operation
By D. John Doyle, Professor of Anesthesia at Cleveland Clinic
Egyptian tablets dating back to 3,600 BC appear to depict tracheotomy operations, and references to the procedure can be found in ancient Hindu scriptures dating from 2000 BC.
Alexander the Great (356-323 BC) is reputed to have saved a soldier from suffocation by making a tracheal incision using the tip of his dagger.
Later, in 100 AD, Antyllus described tracheotomy as a "horizontal incision between 2 tracheal rings to bypass upper airway obstruction," while in 160 AD, the Roman physician Galen wrote, "If you take a dead animal and blow air through its larynx (through a reed), you will fill its bronchi and watch its lungs attain the greatest dimension."
Despite such ancient reports, however, according to Sittig and Pringnitz, before 1,800 only 50 life-saving tracheotomies had been described in the entire medical literature; common clinical use of the procedure would have to wait until pioneers such as Trousseau and Trendelenburg refined and popularized the operation.
In 1833 Trousseau reported on his experience with 200 diphtheria patients treated with tracheotomy. In 1871, Trendelenburg performed a tracheotomy to prevent blood inhalation during upper airway surgery. As experience with the tracheotomy operation grew, consideration to less invasive techniques arose.
In 1880, in Scotland, William Macewen described how to relieve airway obstruction by passing an oral tube into the trachea. He practiced blind, digital intubation using cadaver models and eventually was able to use this technique clinically.
A few years later, in the USA, Joseph O’Dwyer developed a metal tube system that could be passed blindly to relieve airway obstruction in children suffocating from the pseudo membrane formed with diphtheria infections.
Later, George Fell developed an apparatus that could be attached to the O’Dwyer tube system to allow for positive pressure ventilation. This combination was used by Fell and others to provide temporary respiratory support in some patients who were apneic from respiratory depressant drugssuch as morphine.
The combination was also used to treat patients with pneumothoraces and to allow for thoracic surgical procedures. Across the ocean in Germany, Hans Kuhn modified O’Dwyer’s tube system to create a flexometallic endotracheal tube with matching introducer intended for blind insertion.
Of interest, O’Dwyer lived to see his life-saving airway equipment rendered into a largely historic relic as antitoxin research by von Behring and others provided a much-needed remedy for diphtheria in 1890. Immunization against diphtheria began several years later.
One important problem with the O’Dwyer intubation system and its variants was that they had to be placed blindly. The next important development in clinical airway management was thus the development of direct laryngoscopy, which allowed visualization of the glottic structures.
Manual Garcia (1805-1906), a professor of singing in London, England is commonly credited with the discovery of laryngoscopy. In 1855, he described how he could perform autolaryngoscopy through the use of a dental mirror in combination with a second, larger mirror used to direct sunlight into his mouth). This arrangement allowed him to see his larynx and trachea, a feat fortuitously made possible because of his absent gag reflex.
Earlier, as a mere medical student, Benjamin Guy Babington created a glottiscope in 1829. Unfortunately, the invention did not have the impact it deserved. A number of years later, towards the end of the 19th century, Kirstein developed an instrument he called an autoscope
The idea for this instrument came to Kirstein after he learned how an endoscope intended for esophagoscopy had inadvertently slipped into the trachea. His design was subsequently modified by Jackson by providing distal illumination with a tungsten light bulb and other modifications.
The 1940s saw the development of the Miller and MacIntosh laryngoscopes in common clinical use today. In 1941, Robert Miller described his straight laryngoscope blade, while in 1943 Robert MacIntosh described his curved blade. (MacIntosh hoped that by minimizing contact with the epiglottis, that his laryngoscope would be less stimulating).
Tracheal intubation becomes routine
At the same time, in Montreal, Canada in 1942, Harold Griffith introduced curare as a muscle relaxant with a view to facilitating abdominal surgery and other procedures. As a result, tracheal intubation became routine in major surgical procedures.
Although 60 years later variations of the MacIntosh and Miller laryngoscopes are still in common use, because both occasionally fail to provide adequate glottic views, efforts to improve on their designs have continued.
The result has been a continuing series of innovations in laryngoscope design, including developments such as fiberoptic bronchoscopes optimized for intubation, the Bullard laryngoscope and its variants, the McCoy articulating laryngoscope, various optical stylettes, and video laryngoscopes such as the GlideScope and the McGrath video laryngoscope.
Finally, any history of airway management would be incomplete without mentioning supraglottic airway devices such as the Laryngeal Mask Airway (LMA). Dr. Archie Brain, the inventor of the LMA, went thorough a considerable variety of prototype designs before the clinical launch of the LMA in the 1980s.
Many people are unaware, however, that other supraglottic airway were in clinical use long before the invention of LMA, although these devices were eventually eclipsed by the popularization of tracheal intubation following the popularization of curare.