Advanced Airway Management
Your Go-To for Advanced Airway How-To's
2022 ASA Difficult Airway Algorithm
An important tool. Overdue updates.
Airway management saftey in anesthesiology is stagnant
The introduction of the initial 1993 ASA Difficult Airway algorithm helped to usher in a significant improvement in airway safety and decrease in airway malpractice claims.
These safety improvements were specific to the induction of anesthesia. No surprise, as the algorithm itself has classically focused on airway management specific to induction.
So for the last three decades, rates of brain damage and death occurring with difficult airway management have remained very low, yet instances still occur. Patients continue to suffer significant harm and death during airway management. Why is that? The new ASA difficult airway task force identified some theories which include:
​
-
Judgment errors
-
System errors
-
Omitting awake airway management when indicated
-
Delays in progressing to surgical airways during airway management failures
-
Sicker patients
​
The new updated algorithm addresses some of these issues more directly and in a more user friendly way (AND WITH COLOR)
Let’s examine some of the highlights.
​​
.
2022 ASA Difficult Airway Algorithm
New 3 part decision making tool
​
This 3 part decision making tool is entirely new.​​
​
Let's go through a few of the details.
.
Part 1: Pre-induction decision tool
Awake vs. asleep airway management.
It's a crisp tool designed to help providers choose between an awake or post-induction airway management strategy.
​
The gist of the tool indicated that any one of the following factors, alone or in combination, may warrant an awake intubation:
​
-
Suspected difficult facemask ventilation
-
Suspected difficult supraglottic airway placement
-
Risk of aspiration of gastric contents
-
Risk of apnea intolerance
-
Suspected difficult emergency invasive airway access
New ASA difficult airway algorithm infographics
Office Manager
Cognitive aids guide decision-making, and the 2022 ASA Difficult Airway Algorithm includes 4 infographics you can use at the bedside in real time. The infographics use color coding to indicate whether you can ventilate the patient or not. It’s important to note potential accessibility issues in those with color blindness. If staffing permits, it’s helpful for a dedicated person to read the algorithm as airway management progresses.
Part 2: pick a Airway Strategy for Awake Airway Management
A few fine print highlights
Assessment and choice of techniques should be based on their previous experience and available resources
​
Providers are also called on to make a decision between the most appropriate awake technique, be it flexible intubation scope, videolaryngoscopy, direct laryngoscopy, supraglottic airway, combined devices, or retrograde wire-aided OR an elective invasive airway.
​Regardless of technique chosen, intubation success should be confirmed by capnography
Optimize oxygenation, always
Product Manager
While giving oxygen may seem obvious, the task force identified a need to strongly emphasize optimizing oxygenation throughout airway management. Indeed, research and clinical experience show that, in the heat of the moment, focusing on task completion can distract from this most basic responsibility (i.e., remembering to give oxygen to the patient).
You can optimize oxygenation in 2 ways:
-
Administer oxygen via high- or low-flow nasal cannula. Turn it on before you begin airway management and continue it the entire time you manage the airway – this includes extubation.
-
Place the patient in a head-elevated position to maximize FRC by unloading the diaphragm.
Part 2: awake airway management
IF awake airway management should fail...
Follow-up care after a failed awake intubation might include administration of steroids or racemic epinephrine. The patient should be counseled and plans to postpone the case/intubation discussed with patient and team.
Alternative anesthetic techniques might include a regional, neuraxial or local based anesthetic.
​
Or, other options for airway management could include establishment of an invasive surgical airway in an awake patient. Options include a surgical cricothyroidotomy, needle cricothyroidotomy with a pressure-regulated device, large-bore cannula cricothyroidotomy, or surgical tracheostomy, retrograde wire–guided intubation, or percutaneous tracheostomy
​
** FYI, at least in my experience, patients tolerate placement of awake surgical airways under local pretty well.
If awake intubation fails
& the case cannot be postponed, the patient is unstable or becomes uncooperative
A decision may be made to proceed with induction of anesthesia in concert with preparations for emergency invasive airway access should airway management fail. Options would include a surgical cricothyroidotomy, needle cricothyroidotomy with a pressure-regulated device, large-bore cannula cricothyroidotomy, surgical tracheostomy, rigid bronchoscopy or ECMO.
Notably, this does NOT include the following techniques (which are both time consuming and reserved for elective, non-emergent scenarios): retrograde wire–guided intubation and percutaneous tracheostomy
Part 3:
bread & butter Airway management AFTER induction
With a major emphasis on situational awareness, avoidance of fixation error and limitation of attempts
What is a fixation error?
It is the unyielding focus on a single part of a process at the expense of other, often more important, aspects (i.e. oxygenation). During a dire and possibly chaotic airway emergency, a very human inclination can be to fixate on securing the airway while simultaneously neglecting other critical tasks. The passage of time is ignored (often unconsciously) while repeated failed attempts consume precious time.
All the while, the brain suffocates. Anoxia can cause brain damage in as little as 4 minutes. And it can lead to patient death within 8 minutes.
Capnography remains the gold standard for confirming ventilation
And here
The algorithm stresses the measurement of exhaled carbon dioxide to verify gas exchange. Pulse oximetry is not a suitable monitor of airway patency due to the time delay between loss of airway patency and arterial oxygen desaturation.
Focus on extubation
One third of all major airway injuries and deaths occur at emergence.
Transitioning to extubation after a difficult airway deserves consideration, and the new ASA written guidelines provide greater clarity and emphasis of this topic. Task force recommendations include:
​
1. Consideration for a temporary device, such as an airway exchange catheter or supraglottic airway, to serve as guides for re-intubation should the need arise.
2. Consideration of the risks and benefits of elective surgical tracheostomy in lieu of extubation
3. Consideration the best location to extubate as well as available resources and personnel.
4. When feasible, consideration of the use supplemental oxygen throughout the extubation process.
5. Communication of the nature of airway difficulty to the patient and with clear documentation in the patient record.
6. Encouragement for the patient to register with an emergency notification service.
​
** You will notice that these recommendations are not reflected in the ASA algorithms or infographics. As such, I have included a helpful infographic from the UK Difficult Airway Society for reference and I encourage you to read more about extubation considerations.
​​​
Other highlights
Emphasis on oxygenation
It seems obvious, yet in review of available data, the task force identified a need to emphatically emphasize the necessity of optimizing oxygenation throughout airway management.
​
This is highlighted in two ways:
​
1. When feasible, administer oxygen via high- or low-flow nasal cannula. Do so PRIOR to initiating airway management and continue through the entirety of airway management attempts - including extubation, awake intubation attempts, and emergency invasive airway attempts.
​
2. Also, when feasible, place the patient in a head-elevated position during airway management to maximize FRC by unloading the diaphragm.
​​
Part 3:
bread & butter Airway management AFTER induction
A major emphasis on limitation of attempts
The intent of advising clinicians to limit their attempts at tracheal intubation and supraglottic airway insertion is to reduce the risk of bleeding, edema, and other types of trauma that may increase the difficulty of mask ventilation and/or subsequent attempts to secure a definitive airway. Further, persistent attempts at any airway intervention, including ineffective mask ventilation, may delay obtaining an emergency invasive airway when it is called for.
A reasonable approach may be to limit attempts with ANY technique class (i.e., face mask, supraglottic airway, tracheal tube) to three, with one additional attempt by a clinician with higher skills.
Overall, this emphasis on situational awareness and limiting attempts, prompts clinicians to consider a surgical airway sooner than they otherwise might.
Keep in mind that failure is not the PLACEMENTof a surgical airway, it is the DELAY in placing one when needed.
Other highlights
Confirmation of ventilation by presence of ETCO2
Adequate ventilation by any means (e.g., face mask, supraglottic airway, tracheal intubation) should be confirmed by capnography, when possible.
Overall, this recommendation highlights the potential inadequacy of other measures to confirm ventilation (i.e. chest rise, ETT or mask fogging, presence of breath sounds, absence of gastric breath sounds, normal pulse oximetry reading). The perceived or actual presence of any and all of these have all been linked to false positive confirmations of ventilation when ventilation is not truly occurring, causing delays in care and tragic patient consequences.
​​
Black, White and Red all over
Admittedly, there is overlapping redundancy between the 2022 black and white Difficult Airway algorithm and its accompanying colored infographics. That appears purposeful on the part of the ASA task force. A clean, modernized and colorful user interface has clear advantages. Additionally, the colored infographics are meant to serve as real time reference during actual emergencies (i.e. displayed and included with emergency airway carts for reference by helping providers who arrive when help is called for).
However, familiarity with the older algorithm models was also acknowledged by the task force as holding value (la sigh, nostalgia). Either way, providers are encouraged to familiarize themselves with both forms.
Dive deeper.
These changes to the ASA Difficult Airway algorithm are very clear improvements on the previous algorithms. Want to read more about it?
​
Click here.
