A Systematic Approach to Airways

A few weeks ago my wife took me to a glass-blowing studio. The furnaces burned at nearly 2000ºF, and the molten glass oozed like soup as we shaped different items. We were slow and incompetent and needed coaching at every step. At the end of class, we watched as our teachers gracefully blew and spun a large, multicolored glass plate. What would have taken us many hours took them minutes. 

Are your airway skills like my wife and me trying to blow glass for the first time? Or are you the skilled instructor, prepared and competent in every aspect? 

Truthfully, this is a challenging area for EMS. Frequency, suboptimal conditions, scene stress, and transport contribute to challenges we face in the field. And then there is pride. When I speak to medics from the era before video laryngoscopy, they scoff and say things like, “We didn’t need that when I was intubating patients,” “I can’t believe these new medics and all their gizmos,” and “Back in my day I never missed a tube.” 

For reasons that aren’t clear to me, the ability to intubate morbidly obese patients upside down in a car, with their heads pinned in place, is the epitome of paramedic skill. It is a source of great pride in EMS. But this pride sometimes causes poor decisions.

Author Stephen Covey said, “Begin with the end in mind.” The idea is to know our expected outcome, then plan and prepare in a way that almost guarantees success. But how do we do this in the field?

What Is the Goal?

The goal of everything we do in medicine is to improve the health and well-being of our patients. But with airway management that is too broad a statement. What we are aiming for is more straightforward: a patent airway that allows the adequate exchange of oxygen and carbon dioxide at the alveoli. The goal is not to intubate, use an i-gel, perform a cricothyrotomy, or bust out the CMAC. The goal is ventilation and respiration.

All these possible interventions serve as tools to accomplish our goal. But how do we decide which tool to use?

As a teenager in high school auto shop, I was trying to remove a water pump from beneath an engine. I tried every tool I could think of but, due to cramped space and lousy leverage, could not get the bolts loose. Frustrated, I approached the instructor and asked for guidance. He came over, looked inside, and handed me a basic wrench. No fancy sockets or articulated gizmos were needed. 

That same lesson often applies to our airway patients. Recently I responded to a call for an intoxicated 18-year-old male whom his friends said hadn’t been responsive in a few hours. He was seated in the backseat of a sedan, slumped over with inadequate breathing. He was gasping every 10 seconds or so. 

I reached in, lifted his head, and applied a jaw thrust. Suddenly he was able to breathe, and he inhaled deeply while we positioned the gurney and personnel to move him out of the vehicle. That simple tool, the jaw thrust, immediately helped me reach my airway goal. After moving him to the gurney, maintaining that jaw thrust, and supplementing this with an NPA and oxygen, we were able to finish our assessment and treat him properly. 

In other situations we will need that King Vision and suction, etc. Knowing how to decide which tool to use is as important as knowing how to use that tool. 

Making the Decision

In most cases we are good at recognizing respiratory failure. We can tell when people aren’t breathing. In medic school they drilled us incessantly on identifying and intervening during respiratory emergencies. Never in any of those drills did anyone ask if we should intubate based on the patient’s anatomy or the circumstances around the emergency. 

Each unsuccessful attempt contributes to poor patient outcomes. For every missed tube, the incidence of adverse events increases. By the time you’ve tried twice, almost 50% of those patients will have an associated adverse event.¹ If we can get the tube the first time, great.  If we aren’t sure we can, what tools can we use to decide to attempt the intubation or try another adjunct? How do we determine the best course of treatment when success is unlikely and could worsen the patient’s outcome?

The gold standard should be what is best for the patient—not regardless of the circumstances but specifically based on the circumstances. Does the patient have an anatomical situation likely to make intubation difficult or improbable? Is the environment going to reduce or inhibit our ability to successfully intubate this patient? Are we not as well practiced as we should be? 

These are all realities of the profession we have chosen. If our focus is always what is best for this patient in this situation with this care team available, we will steer clear of poor intubation attempts and poorer outcomes. 

Being Our Best

The truth is that EMS personnel excel at managing less-than-ideal circumstances. We thrive in the confusion of the field. We can organize and perform with multiple patients, loud scenes, and insufficient resources. But of all the craziness we encounter, the thing we have the greatest power to influence is our competence. We can show up skilled, calm, and confident, or confused, unpracticed, and unprepared. 

We don’t get to decide if the patient will be obese, pinned in an awkward position, or have a tumor growing in their oropharynx. But if we are practiced, thoughtful, and calm, we can decide the best course of treatment and have the skills available to implement it. 

A systematic approach to airway management starts in the classroom. When was the last time you practiced intubating? Have you had someone watch you intubate recently and critique your setup and approach? Have you recently looked at best practices or adjuncts to improve your skills? 

These are all low-cost, easy-to-do options that will better prepare you for the field scenarios bound to come your way. 

The second part is to assess the patient airway prior to the attempt. I know I am guilty of recognizing the need for a tube but then not thinking about the problems I’d encounter along the way. This is where the acronym LEMON can be particularly helpful. 

LEMON stands for look, evaluate, Mallampati, obstruction, and neck mobility.² The first step seems trivial, but it sets the stage for a calm, clinical approach to airway management. Just look around and think about the potential problems you could run into. Signs of problems might be lots of vomit, facial and airway trauma, deformities, or the position of the patient relative to you and a flat surface. 

We then proceed to the 3-3-2 evaluation. My twin daughters recently had tonsillectomies, and the anesthesiologist performed this test in about 15 seconds while talking with them. He simply asked them to open their mouths and then looked at their throats and held his hand up to their necks. It was simple and covered both the Mallampati and 3-3-2. The 3-3-2 involves being able to place three fingers between the upper and lower teeth at the front of the mouth, three fingers between the chin and neck/hyoid bone, and two fingers between the hyoid bone and the notch in the thyroid cartilage.²

If everything looks good, we can then open the mouth and see how much of the posterior oropharynx is visible. This is the Mallampati score. Basically, can we see all the uvula and back of the oropharynx? If so, that is a promising finding scored as a 1 on the chart. As the views become increasingly obscured, the score ranges up to to 4. At 2 we can see a little of the posterior pharynx. At 3 we can only see some of the uvula, and at 4 we can’t see much of anything. 

Obstruction is pretty straightforward. Are there things in the way? These could be vomit, teeth, tumors, or food. We should remove the ones we can and note the ones we can’t. Lastly we should look for and evaluate neck mobility. Does the patient have severe posture problems that inhibit neck mobility? Are they in a c-collar and restricted from movement? 

This assessment may sound overly involved, but the truth is that it only takes a minute to perform and sets the stage for success. 

Field Application

Realistically, most studies around intubation results are done in hospitals, in ideal conditions with anesthesiologists. Our situation is different, and we often don’t get to choose the circumstances that dictate our need to intubate. Again, our goal shouldn’t be to intubate for the sake of it—our goal is adequate respiration and ventilation. But how do Mallampati, LEMON, and the 3-3-2 assessment help us achieve that goal when intubation appears to be the best option for our patient? 

It’s like attempting an IV on a critical patient: When you have someone who is extremely ill and you need a line but can’t find one, just digging into their arm with a needle is a poor clinical decision. You will probably resort to some well-established tricks. You might use a light, hang the arm for a while, or turn to an EJ or IO. 

Think of airway management in the same way. If the situation you face contains physical elements like access problems, hazards, or major facial trauma, think about tools you have to mitigate those problems. Maybe before you intubate this patient, you should move out of the cramped bathroom and into the more spacious living room. 

Once those challenges are reduced or eliminated, move to the rest of the assessment. If the 3-3-2 is normal, look for the posterior pharynx. If you have a nice view, proceed as normal. If the 3-3-2 isn’t normal and the Mallampati is a 3 or 4, consider what tools can help you manage these anatomical difficulties. I would grab the video laryngoscopy equipment and a bougie and ask someone to get ready to help with cricoid pressure. You may even want to prepare multiple tubes of different sizes in case you need to downsize. Depending on your system, there might be an opportunity to ask a more experienced medic to get the tube. 

You could even break this down into a simple algorithm: 

• If LEMON is normal, prepare for and expect a normal intubation.
• If L reveals problems or hazards, address as needed. 
• If EMON is abnormal, prepare video laryngoscopy, bougie, LMA, an assistant for cricoid pressure, etc. 

Simply put, give yourself the best chance at successfully intubating on the first attempt. LEMON helps us know what problems to expect and get the gear and people ready to help us. If things look really bad, we may resort to an adjunct because it will improve oxygenation more effectively and quickly. 

Sometimes we do get called for that obese male pinned upside down in the vehicle with a compromised airway. This patient has a much better chance of survival if we can get that tube quickly and safely. We will have a much better chance of getting that tube when we recognize the difficulty and prepare for it. 

In the End

Our goal is always to provide the best level of care we possibly can. Our focus is adequate oxygenation and respiration. LEMON helps paint the road map to a successful tube or adjunct. 

We are good at what we do. We save lives every day. Approaching our patients and setting our pride aside while bringing competency with us is the way to success.  

References

1. Sakles JC, Chiu S, Mosier J, Walker C, Stolz U. The importance of first pass success when performing orotracheal intubation in the emergency department. Acad Emerg Med, 2013 Jan; 20(1): 71–8. 

2.Gnugnoli DM, Singh A, Shafer K. EMS Field Intubation. In: StatPearls [Internet]. Treasure Island, Fla.: StatPearls Publishing, 2020. 

Adam King is a paramedic/firefighter, FTO, and CQI committee member for a medium-size department in California. He is also the lead consultant at In the Field Training. Reach him at Adam@inthefieldtraining.com.