Editor’s note: This series of articles profiles the inventors of three innovative emergency medical care devices offered by Pulmodyne, an Intersurgical Company.
While it’s long been the prehospital standard for airway control, endotracheal intubation is one of the more challenging skills in the EMS repertoire. Done in the field, it has higher complication and failure rates than in the hospital.1 Various reasons go into that, including characteristics of patients (e.g., mouth trauma, difficult anatomy), providers (experience, comfort) and scenes (suboptimal locations and conditions). A 2014 review of data from 40 states revealed an overall out-of-hospital ETI success rate of 85.3%.2
Even with straightforward airways, getting the tube down the throat requires some assistance. Historically, that’s been achieved with a stylet – a malleable metal rod placed inside the endotracheal tube to help guide it down the trachea. Harder intubations often call for a bougie – a thin plastic rod inserted into the trachea, smaller in diameter than the stylet, over which the tube is passed. Data over the last decade has suggested that bougies may produce more successful first attempts (though a randomized clinical trial published in 2021 didn’t find a difference), and experts have begun warming to their routine use.3
Whatever your selection, it’s important to be quick and accurate in getting the introduction device and tube placed – it’s a vital temporizing measure for patients in dire states.
“Most of what we do in emergency care is stabilizing and passing off,” said prominent emergency physician Richard Levitan, M.D., who has invented several key devices to benefit EMS and hospital airway management. “When you push drugs, people stop breathing, and you have to secure the airway. It’s one of the few times in emergency care where you’re fully responsible for the patient by an act of commission. If you mismanage the airway, there’s no passing it off – you’re going to have a dead or brain-injured patient.”
Those are high stakes when you’re trying to steer a flexible tube into a glottic opening that can be hard to see and reach. The Universal Stylet Bougie (USB), invented by Levitan and designed and developed by Intersurgical, is now available, helping EMS providers find their target while potentially increasing first-pass success rates.
EXPERIENCE PAVES THE WAY
A career’s worth of experience in emergency care and airway management paved the way for the USB’s invention.
Before he became part of the first class of emergency medicine residents at New York’s Bellevue Hospital in the early 1990s, Levitan discovered emergency services. He’d dropped out of college after a year and hitchhiked to Idaho, where he ended up fighting wildfires. He had an opportunity to be a wilderness ranger, but to do this he needed first aid training that he couldn’t obtain in Idaho. Instead Levitan returned to New England and became an EMT, then a paramedic. “That summer I worked New York City EMS and fell in love with EMS,” he recalled. “I decided instead of being a forest ranger, I wanted to be an ER doc.”
He went to medical school, then on to Bellevue. By the end of his residency, he was taking anesthesia rotations and preparing a move to Johns Hopkins to pursue double-boarding – but life intervened. The untimely death of someone close interrupted the plan. But that same week, Levitan had the idea for what would become his best-known creation, the Airway Cam direct laryngoscopy video system.
Airway Cam took several years to bring to reality, but once it hit the market, it let Levitan start delivering video-based lectures and education using the device. However, the need for subjects left him a bit hamstrung. “You can’t do repetitive laryngoscopy three times on the same patient just for research,” Levitan noted. The answer to that problem was cadavers, obtained through an anatomic gift program in Maryland.
For the next two decades-plus he ran multiple courses each year, and gradually these came to the attention of device manufacturers. They had products and product ideas, and he had the capacity to test them on manikins and cadavers, rather than live humans.
Levitan’s creations during this period included intubation training manikins for teaching laryngoscopy, as well as an anatomically correct surgical trainer, plus the Levitan FPS optical stylet, the Control-Cric cricothyrotomy kit (available from Pulmodyne, which was recently acquired by Intersurgical), and the USB.
The latter happened through a bit of a happy accident.
ONGOING CHALLENGES PROMPT A SOLUTION
The Airway Cam was a helpful innovation, but it didn’t resolve the issue of the tube blocking the intubator’s line of sight during laryngoscopy. As a countermeasure Levitan taught straight-to-cuff stylet shaping, which inserts the stylet straight, rather than curved (so it remains below the line of sight), with a bend of no more than 35 degrees, just beyond the proximal end of the tube cuff.
To better control bougies he conceived what is called the “shaka grip.” A reference to the extended thumb and pinky gesture associated with surfers, the grip was a way to fold the bougie over, hold it with the middle three fingers and direct it while controlling which way the tip was pointed.
These were successful modifications, but Levitan wanted a more definitive solution to these ongoing challenges.
“With my understanding of stylet shaping and some of the optics involved with that and my efforts trying to improve bougie handling,” Levitan recalled, “it occurred to me I could develop a better bougie that could work as a stylet.”
He began experimenting, adding aluminum tape to the ends of bougies to help control their shape. The result could functionally work as a stylet, and he could shape it enough to work with hyperangulated video laryngoscopes. The concept for the USB was emerging.
A second epiphany completed the process: Levitan added a second metal section in the middle of the bougie. That concentrated the device’s movement within the flexible section between the metal in the middle and the metal at the tip. “The movement between the two sections would be amplified,” he explained, “and the effect of that mechanically would be to make the tip bouncier as it interacted with the tracheal rings.”
That’s where the shaka grip comes in: Because the tracheal rings only cover the anterior two-thirds of the trachea – the back wall is flat – the bougie tip must remain oriented toward the tracheal rings and can’t rotate. The shaka grip helps prevent inadvertent rotation of the bougie inside the tube.
“A lot of bougie enthusiasts will say, ‘Oh, I can feel the rings 9 out of 10 times,’” said Levitan. “But it’s often not clear that you’re feeling the rings. And the reason is, you don’t know which way the tip is pointing. If you’re holding a bougie that’s a cylindrical rod, it doesn’t have directional control – it easily rolls in your hand. And although there are markings on the upper side, it’s very hard to see them while you’re using the device, so you don’t really know where the tip is pointing.”
Levitan molded his resulting product for inherent directionality, so when it’s held in the middle, the proximal end, pointing away from the intubator, and the distal tip are both oriented to 12 o’clock. “So under an epiglottis-only view,” Levitan added, “I can know which way is up.” He also made the USB hexagonal instead of cylindrical so, with only six points of contact rather than an entire circumference, there would be less friction along the tube, making it easier to insert and remove the device.
A final design touch involved flattening the tip of the proximal end. That lets it be tucked back over and into the proximal end of the tube to prevent accidental movement before the tube is railroaded over the USB. An ancillary benefit was that the new device could be packaged smaller – about the size of a tracheal tube – whereas traditional bougies are carried straight and thus harder to pack conveniently.
The final product met the range of anticipated needs as deftly as Levitan had imagined. It was rigid enough to function as a stylet, yet flexible enough to work as a bougie. And it would be quick and convenient in both EMS and EDs.
“You can use this as a regular stylet, you can use it as a bougie, you can use it as a hyperangulated stylet, and you can use it as a hyperangulated bougie,” he said. “The USB replaces multiple devices, and I believe it works better as a bougie than a regular bougie, better as a stylet than a regular stylet, and better as a hyperangulated device.”
AIRWAY PROVIDERS MUST BE ONE-AND-DONE
When the USB was ready for unveiling, Levitan brought it to Intersurgical – a manufacturer he knew could engineer it right.
“What I’ve discovered as an inventor,” he said, “is that it’s one thing to have an idea. But really, the only reason any product works is because an engineer then put their shrewd insight into how to produce it cost-effectively and efficiently. Without that, it wouldn’t work. And when I shared my idea about the USB, they instantly understood, even though it’s more complicated than a bougie, how it could be produced.”
Intersurgical loved the idea and brought it to market in 2021. It’s now assisting intubators in both EMS and hospital settings in a range of cases both challenging and straightforward.
“There are a lot of uses for this device,” Levitan said. “I work in a little hospital in the middle of nowhere, and if I get called to the ICU, I’m managing that airway with no backup. I’ve had cases like a 6 1/2-foot, 450-pound guy with COVID-19, where I put a laryngoscope in and could barely see the epiglottis. But even with that view, I drop the USB in, feel the tracheal rings and am like, ‘Phew – done!’
“There are cases where the epiglottis is long and curvilinear, which we see more and more with obese people. I’ve had cases where tube delivery was tight because the mouth wouldn’t open or a rigid stylet kind of hung up. You don’t have a lot of movement when you’re using a hyperangulated rigid stylet. And I’ve switched to the USB, and it’s like, ‘Oh, done!’
“What’s changed over the years is that acceptable risk has gone down,” he added. “As airway providers, whether you’re an EMS medic, ER doc, ICU doc or anesthetist, we have to basically do one-and-done. We can’t risk prolonged and repetitive airway efforts because in critical patients, those are associated with bad outcomes. So like with the rest of our lives, we’ve grown less accepting of risk. And that’s a good thing. Let’s make sure we’re getting this one-and-done. And the USB I think addresses that really well.”
For more information visit Intersurgical and Pulmodyne, an Intersurgical Company.
REFERENCES
1. “EMS field intubation.” David M. Gnugnoli, Abhishek Singh, Katherine Shafer. StatPearls [Internet]. 2023. www.ncbi.nlm.nih.gov/books/NBK538221/
2. “An update on out-of-hospital airway management practices in the United States.” Leigh Ann Diggs, Juita-Elena Wie Yusuf, Gianluca De Leo. Resuscitation. July 2014. https://pubmed.ncbi.nlm.nih.gov/24642405/
3. “Effect of use of a bougie vs endotracheal tube with stylet on successful intubation on the first attempt among critically ill patients undergoing tracheal intubation: A randomized clinical trial.” Brian E. Driver, Matthew W. Semler, Wesley H. Self, et al. JAMA. 2021. https://jamanetwork.com/journals/jama/fullarticle/2787158
