Managing the Difficult Airway
June 11, 2021
Written by Aaron Lacy
The difficult airway is rare, and adverse events from difficult airways are higher in the ED than other settings. With the cornerstone of expert clinical technique and skills, the main areas of focus in the difficult airway are airway assessment, planning, and appropriate response to difficulty, in combination with human factors.
Why does this matter?
Management of the airway is a requisite skill for emergency providers – but what separates the wheat from the chaff is the ability to manage the difficult airway. There are over 15 million intubations per year in the United States, with ~350,000 of them occurring in the emergency department. While the incidence of a difficult airway is low, given the sheer volume of ETTs being put into tracheas each year, any small change in performance will carry great weight. We need to be able to handle difficult intubations and handle them well.
Knees weak, arms heavy, the patient’s airway is filled with mom’s spaghetti
The incidence of difficult tracheal ventilation ranges from 5-8%, with failed intubation representing 0.05-0.35% of all attempts. When performing any airway, you should be predicting the difficult airway and reacting quickly and effectively to the problem.
Remember there are both anatomically and physiologically difficult airways.
The best predictor of a difficult airway is a known difficult airway – but this is not always feasible information to obtain.
The best anatomic predictor we have to date is the upper lip bite test – which is difficult to ask critically ill patients to perform and still only gets us to 60% sensitivity.
Most of the other tests are abysmal predictors – I’m looking at you, Mallampati.
In short, predicting a difficult airway, especially in the ED, is not always feasible. We must be mentally and structurally prepared for any intubation to be difficult. There is no harm in predicting a difficult airway and having it end up being an easy one. It’s better to overestimate and over-prepare.
There are both anticipated and unanticipated difficult airways.
Difficultly with bag-valve-masking – performing an airway isn’t just passing the tube, it starts the moment you decide to intubate. BVM can save you from difficulty with laryngoscopy or intubation. If you are running into trouble, have ready and reach early for airway adjuncts (NP and oral airways).
Difficulty with supraglottic placement – the role of supraglottic airways as a primary means of ventilation and a rescue device are critical. Everyone says an LMA is easy, but it’s a bit harder than it looks, especially in a mangled face. Know your equipment and don’t be afraid to buy time by placing one.
Difficult laryngoscopy or tracheal intubation – there’s no point in having fancy tools if you aren’t going to use them. When faced with a difficult airway, reach for the video laryngoscope and bougie, and don’t be afraid to fall back on your supraglottic or BVM.
Can’t intubate, can’t ventilate – cut the neck. It’s not a failed airway if the patient is oxygenated and ventilated; don’t delay if the situation is getting worse.
The big takeaway here is to take every airway seriously. Hone your skills so you can rise to the occasion when you are faced with your next difficult intubation. It’s coming, even if you don’t know it.
This article also discussed awake intubation and extubation of the patient with known or predicted difficult airway. Our audience is doing primarily RSI, so I chose to focus on that. If you want to read more, check out the whole article below – it’s excellent.
Management of the Difficult Airway. N Engl J Med. 2021 May 13;384(19):1836-1847. doi: 10.1056/NEJMra1916801.