One of the most important things you’ll do as a prehospital medical provider is manage patients’ airways. It can also be one of the most challenging, as any provider who’s ever tried to secure a difficult airway in tough field conditions knows.
If that’s you, you’re not alone; clinicians have struggled with practices like laryngoscopy and intubation literally for centuries. The tools and techniques they use have improved, and both practices are certainly done more easily and successfully now than ever – yet cases can remain troublesome, and the experiences not always pleasant.
“Difficult airways are one reason, and the need for different techniques with different devices,” said Rich Capece, an EMT from Rhode Island who works in acute care and monitoring sales for the major medical supplier Medtronic. “Some of the devices out there can be kind of clunky and not comfortable for new users. Can they still intubate? Yes, but it’s not always a familiar technique.”
While the tools for laryngoscopy aren’t yet universal or foolproof, they really have come an enormous way. Consider some of what your predecessors have used over the years and how much work it’s taken to get to where we are today.
EARLY HISTORY AND KEY ADVANCES
The earliest technique for managing respiratory distress was a crude tracheostomy, the first descriptions of which date as far back as ancient Egypt.1 Even early clinicians, however, recognized the value of seeing down the airway, and in the seventh century the Byzantine physician Paul of Aegina invented the “glossotrochus,” a polished steel tongue depressor that fastened under the chin to help expose the fauces.2 Perhaps the first attempt at intubation and positive-pressure ventilation came from Dutch physician Andreas Vesalius, who wrote in the 1500s about ventilating a dying animal via a reed in the trachea – a technique, Vesalius ruminated, that could save lives. Vesalius’ work, however, was overlooked in his time and didn’t impact medical practice for several centuries.3
The biggest early hurdle to laryngoscopy was illumination. A notable attempt to provide it came from German physician Philipp von Bozzini, who in the early 1800s devised a tool that used two parallel tubes with mirrors and a speculum and a candle in the handle. One tube was for illumination, the other for viewing – the first known use of an external light source to illuminate a body cavity for examination and hence the first endoscope.
By the 1820s English physician Benjamin Guy Babington had conceived a “glottoscope” that used a speculum to displace the tongue and a system of mirrors reflecting sunlight to visualize the larynx. A fellow doctor wrote about Babington performing a laryngoscopy on him, and his colleague Thomas Hodgkin coined the term “laryngoscope.”
The earliest person to view an entire functioning glottis in a living human wasn’t a medical professional but a Spanish “vocal pedagogist” – an expert in vocal instruction – in 1854. Manuel Garcia built a device with two mirrors that used the sun for illumination and successfully looked into his own trachea. Three years later a pair of European docs, Austrian Ludwig Turck and Hungarian Johann Czermak, were among those leading the adaptation of Garcia’s approach to clinical practice. Sunlight proved too weak for Turck’s mirror system, but Czermak tried a brighter artificial light and concave ophthalmic mirror to focus it in the back of the pharynx. Both claimed to be the first to use laryngoscopy clinically, and the French Academy of Sciences, unable to determine who was correct, made them share a medal for it.
References to nonsurgical intubations increasingly began popping up in medical literature of the late 1800s. However, all observations of the glottis and larynx remained indirect until the work of German doctor Alfred Kirstein, who described the first direct visualization in 1895 using a modified esophagoscope with external electric illumination. Kirstein kept careful notes, including specifying the optimal “sniffing” position, and is thus remembered as a key architect of direct laryngoscopy.
Once the lighting issue was resolved, production of laryngoscopes and other types of endoscopes boomed. American physician Chevalier Jackson designed a U-shaped laryngoscope he initially used with a headlamp, then later added a light to its distal end – key to enabling a lateral approach, rather than midline – and published his work in 1913. Jackson tinkered further with designs over the next two decades, including focusing on handle ergonomics.
Around that same time, American Henry Janeway became the first anesthetist to publish on direct laryngoscopy. He designed a laryngoscope specifically for tracheal intubation; this also used a distal light source but added batteries in the handle, a notch in the blade for keeping the tube midline, a shorter distal end that eliminated the need for magnification, and a slight curve at the blade tip to ease movement through the glottis.
Key advances after World War I came from several contributors whose names remain familiar today. Sir Ivan Whiteside Magill designed a U-shaped laryngoscope descended from Jackson’s and the angulated forceps still used today. Magill shared his technique with colleagues from the Mayo Clinic, resulting in several articles that brought the growing practice to wider attention.
Texas anesthesiologist Robert Arden Miller first described his now-eponymous laryngoscope blade in the early 1940s. It’s known as the “straight” option alongside today’s popular curved designs, but it nonetheless has a small curve near the tip to lift the epiglottis. Sir Robert Macintosh introduced his curved alternative in 1943 (although he was not first with the idea), and it’s the most widely used laryngoscope blade for orotracheal intubation today. Macintosh also pioneered an endotracheal tube introducer that inspired the Eschmann model three decades later.
FIBER OPTICS AND VIDEO
The development of fiber optics further improved lighting and visualization of the larynx during the second half of the 20th century, and the first fiber-optic intubation was chronicled in 1967. Multiple devices using that technology followed.
However, even as the tools to perform it advanced dramatically in the late 1900s, direct laryngoscopy still failed sometimes. A universal answer was hard to find; even fiber-optic scopes had issues with lens fogging. Video laryngoscopy emerged around 2000 and represented perhaps the greatest advance in the practice to date.
The first video laryngoscope hit the market in 2001 and used a high-resolution camera connected by cable to an LCD monitor. The camera was on the blade, with a heated lens to avert fogging and no fiber-optic components, and its integration improved images and reduced costs. Video laryngoscopes quickly proliferated in the aughts, with some minor variations in features – channeled versus nonchanneled, angulated versus nonangulated, method of insertion, method of display – but consensus was they produced better results than direct attempts at laryngoscopy. A growing body of evidence backs that up, including a 2023 trial of first-pass success stopped early for efficacy.
“The way I like to explain it to folks is that video laryngoscopy is like having a rear-view camera in your car,” said Capece. “We all know how to back up a car into a parking space. But having that camera just makes it so much easier.”
The rise of video laryngoscopy was not without controversy when the company behind that first device raised a patent dispute against a Scottish company that produced its own video laryngoscope – a similar product conceived by a young design student named Matt McGrath.4 Those claims failed, and in 2015 McGrath’s company, Aircraft Medical, and its video laryngoscope were acquired by Medtronic.
A SUCCESSFUL DEVICE IS FURTHER IMPROVED
All of that history brings us to the latest advance in the field: Medtronic recently upgraded the McGRATH MAC video laryngoscope. The company has brought several improvements to the already-successful device, including enhanced optics and a brighter LED; improved durability; and intelligent battery management with a minute-by-minute capacity indicator and automatic shutoff after use.
The McGRATH MAC video laryngoscope combines line-of-sight portrait-view video with the Macintosh insertion technique favored by most providers, making it easy for new users. With three times the brightness and four times the resolution of its predecessor, it helps improve first-pass success, reduce time to intubation and reduce hemodynamic response to intubation.
“It’s a simple device – one button turns it on and off. So just being able to pick something up, turn it on and be good to go is great,” said Capece. “You don’t have to plug it in, you don’t have to hook it up to another screen. It’s basically plug and play.”
The McGRATH MAC video laryngoscope comes with a hard-shell carrying case that can hold blades and a spare battery, as well as a three-year warranty. Medtronic has worked to keep the price affordable.
As easy as the McGRATH MAC video laryngoscope is to use – and as far as laryngoscopy tools have come in the last five millennia – Medtronic also still offers extensive support for those who use it, including a range of education and resources.
“As a big company, we have so many training resources – one-pagers, brochures, webinars, videos, video in-services and things like that,” said Capece. “We’re always willing to hop on with a department and answer questions.”
For more information, visit Medtronic.
REFERENCES
1. “History of tracheal intubation.” Wikipedia. https://en.wikipedia.org/wiki/History_of_tracheal_intubation
2. “Pioneers of laryngoscopy: indirect, direct and video laryngoscopy.” B.M. Pieters, G.B. Eindhoven, C. Acott, AAJ van Zundert. Anaesthesia and Intensive Care. July 2015. https://pubmed.ncbi.nlm.nih.gov/26126070/
3. “History of mechanical ventilation. From Vesalius to ventilator-induced lung injury.” Arthur S. Slutsky. American Journal of Respiratory and Critical Care Medicine. March 2015. www.atsjournals.org/doi/full/10.1164/rccm.201503-0421PP
4. “Edinburgh’s Aircraft Medical sold in $110m deal.” Gareth Mackie, Kristy Dorsey. The Scotsman. November 2015. www.scotsman.com/regions/edinburghs-aircraft-medical-sold-in-110m-deal-1489339
McGRATH MAC is a registered trademark of Medtronic.
