Chapter 1, ‘Why airway management matters’ introduced the importance of “human factors” (HFs), namely nontechnical factors that affect behavior and performance, at each of four key levels: individual, team, environment, and system. Substantial evidence shows that most of all major human errors (understood as competency-based deviations) and mistakes (understood as performance-related, even though the practitioner has the knowledge) have a nontechnical, rather than merely a technical cause. This adds another layer of complexity to airway management. In turn, airway management can also be difficult because of anatomic challenges (e.g., an irradiated neck), physiologic dangers (e.g., pulmonary hypertension or ARDS), or situational obstacles (e.g., practitioners are stressed, unfamiliar with each other, unable to work together, or forced to resuscitate in an unsuitable environment). Thus far, this book has largely focused on the anatomic and physiologic aspects of airway management and technical remedies. This chapter advances those skills by emphasizing cognitive and interpersonal skills, especially when there is situational difficulty.

These nontechnical aspects of airway management are not mere window dressing. True airway expertise includes “verbal” and “team” dexterity, not just “manual” dexterity; and accepting that “a team of experts” is not necessarily an “expert team.” In short, insufficient nontechnical skills can harm patients, all on their own. This means that an expert with a laryngoscope can still be a danger if they cannot work with others, handle stress, or communicate. Similarly, understanding nontechnical skills helps explain how optimal preparation can fall apart at the first sign of trouble, or alternatively, how adept novices can save lives and resilient teams can excel despite crises. We have assumed these skills were innate and unteachable for too long. Notably, the literature does not support this assumption. Instead, just as with technical skills, we need to share the nontechnical curriculum, hone our expertise, practice until perfect… and then continue practicing.

The importance of nontechnical skills was highlighted by aviation over 50 years ago and summarized under the umbrella term, crew resource management (CRM).¹ These insights have been adapted to other high-stakes professions because humans react in predictable ways whenever there is excess stress, time pressure, and ad hoc members (i.e., flash teams). In acute care medicine, CRM now stands for crisis resource management, and comprises six subheadings: situational awareness, decision making, communication, task management, leadership/followership, and teamwork.^1,2,3 Once we accept that HF and CRM can be the difference between tragedy and rescue, the sobering airway safety literature makes sense, along with the pressing need to address collective shortcomings. For example, the American Society of Anesthesiologists’ (ASA) closed claims database,
which are used to indirectly assess anesthesia safety in the United States, reported that 76% of cases included predictors of difficulty, 73% reported inappropriate management, 39% of “cannot intubate, cannot oxygenate” (CICO) scenarios had delayed or no cricothyrotomy, and a first judgment failure was often followed by a second or third.⁴ Thus, the three core actions to improve airway management outlined in Chapter 1 are ([1] Assess for potential difficulty and danger, [2] Prepare for the difficulty and danger, [3] and to Recognize and manage failure). Similarly, the two cardinal rules are ([1] Do not wander into failure, [2] Intubate with a team, not an audience) and do not assume the solution is merely “be the best with a laryngoscope.” It is time to accept that airway management is a team sport, and that CRM influences all of the components of safety (Fig. 39.1).

HF is a broad discipline, and hard to cover in one chapter. In short, however, it is best understood as a scientific discipline that incorporates principles of engineering (fail safes, standard operating procedures), ergonomics, (how to design systems that enable humans to function in their environment), and psychology (how we perform despite fear, fatigue, and unfamiliarity). We will discuss HFs at four levels: individual, team, environment, and system over the next two chapters. HF proponents see both errors and successes as opportunities for debrief, reflection, and perpetual improvement. In other words, minor iterative gains can add up to major improvements.⁵ For example, patient safety can be threatened by an individual’s cognitive biases, a team’s rigidity, an environment’s shortcomings, a system’s complexity, and the management’s indifference; all without a laryngoscope ever being touched. Minor improvements can be made in each of these four areas, leading to dramatic improvements in patient safety and team resilience. With these noble pursuits in mind, let’s shine a light on the good, bad, and ugly of ourselves as solo practitioners. We will then dissect the team, environment, and system.

Airway management in critically ill patients meets the definition of a “crisis situation.” Namely, the circumstances are rife with uncertainty, there is danger to a patient’s life, there is the need for immediate action, and it is difficult (or impossible) to control everything.⁶ In other words, airways are inherently stressful, and that stress is further amplified by anatomic or physiologic difficulty. The unfortunate conundrum is that stress has deleterious effects on cognitive and psychomotor faculties. So, just when clinical performance needs to be at its best, it can potentially be most compromised.

Situational awareness suffers when under stress. Stressful situations can cause team members to be overwhelmed and lose global awareness and focus, excessively, on discrete tasks. Additional environmental factors such as noise, visual distractions, or situational time pressure magnify this effect.^7,8 This attentional narrowing, often referred to as “increased selectivity,”⁹ results in unawareness of important information¹⁰ and/or fixating on less important tasks.^11,12 All of this has implications for airway management. For example, Cemalovic investigated emergency physicians’ perception of time and oxygenation parameters during intubation and found that providers believed that they were much faster than they actually were.¹³ More concerning was that providers consistently did not recognize desaturation during intubation attempts.¹⁴

Stress also causes detrimental effects on information processing, working memory, and recall.^14,15,16 The ability of the brain to focus on discrete pieces of information and keep that information immediately available is compromised.^17,18 This causes significant compromise in one’s ability to solve complex or novel problems.^19,20 Finally, there are marked effects on the brain’s ability to retrieve information from long-term memory.^21,22,23,24 This means that if a provider encounters an unanticipated challenge, they will be less able to problem solve quickly and efficiently.

Even your psychomotor skills suffer in stressful situations, as exemplified in high-stress law enforcement.²⁵ Under stress, both gross motor skills and fine motor skills seem to deteriorate,^26,27,28,29 and similar findings were seen with surgical skills.^30,31,32 While there are no studies conclusively demonstrating these findings in airway management, the totality of the available evidence and anecdotal reports suggests similar deleterious effects.

Overall, it is important to recognize the fundamental effect of acute stress on cognitive and technical skills performance. Once we understand the psychological and neurologic effects of stress, we can better explore the macroscopic aspects of human behavior and HF engineering that can help us improve difficult airway management.

It is the bottom of the last inning of the deciding game of the World Series. The bases are loaded, only one out remains, and your favorite team is behind with the best hitter in the game up to bat. It is the sports equivalent of a “life-or-death” or “all-on-the-line” situation. It is stressful, everyone is watching, and the batter cannot call on anyone else. The pitcher, who throws fastballs 90% of the time, throws a curveball which the batter recognizes, adjusts the swing, and smashes the game-winning home run. The batter, despite the stress of the situation, had enough cognitive bandwidth to perceive new information. They adapted to the new information and won. Sports imitates life… or does it?

In January 2009, U.S. Airways 1549 departed LaGuardia airport and struck a flock of geese two minutes after takeoff, killing engine power to both engines at an altitude of only 3,000 feet. Restarting the engine was impossible, so an emergency landing was necessary. The pilots also decided that they should not turn back to LaGuardia, or proceed to a smaller airport in New Jersey, because this would likely result in a catastrophic loss of life (something later confirmed by simulations). Hence, an emergency landing was needed and Captain “Sully” Sullenberger chose a spot in the Hudson River with nearby water traffic that could rescue the passengers and crew from the frigid water. Everyone survived, and Sully was deemed a hero.³³

We love these stories where a single hero overcomes overwhelming odds when everything is on the line, particularly if that hero is an underdog. The reason we love these stories so much is because the outcomes are improbable and the details are usually oversimplified. In high-stress, high-stakes situations, the most likely outcome is failure, as novices often develop cognitive overload and experts can become complacent. The most likely outcome is for that batter to strike out, fly out, or ground out. In fact, according to the Baseball-Almanac.com, of the top 10 home run leaders in professional baseball history, each of them had twice as many, and in some cases, three to four times as many, strikeouts as home runs. This also transcends sports. Three of the greatest basketball players of all time, generally considered the most clutch players in a game-on-the-line situation—Michael Jordan, Kobe Bryant, and Lebron James—all missed more go-ahead shots than they made at the end of the game. In fact, at best, they only make the shot half the time.

Instead of landing in the Hudson River and saving the entire crew and passengers, the more likely outcome for U.S. Airways Flight 1549 would be a fiery crash and multiple casualties. Unfortunately, United Airlines Flight 173, from Denver to Portland is more typical. It is also more informative.³⁴ Flight 173 was adequately prepared, with nearly 50% more fuel than needed, and a more experienced crew than U.S. Airways Flight 1549. However, a problem with the landing gear on approach led to delays while the pilots circled the city and tried to troubleshoot. For the next hour, they failed to notice (a fixation error) that they had run out of fuel. They ultimately lost engine power and crashed into a Portland suburb, killing 10 and injuring 23.

In short, we might think that we will be heroic under stress, but unless we have prepared, we likely will not. We cannot just rely upon innate skill, or underestimate the dangers of complexity, distraction, or stress. We may all have done something ill-advised at one point and gotten away with it. As outlined below, that heuristic can give a false sense of security, just as doing something uncommon and struggling mightily can give a false sense of risk. As the old aviation adage states: “pilots do many things: among the easiest should be flying the plane.” Fortunately, most flights go well just as most airways are managed, but not all. Experts commit to life-long training so that they are efficient during routine days, but also vigilant for the unusual and perilous.

Safety-I focuses on as few things going wrong as possible, and Safety-II focuses on as many things going right.³⁵ Both are needed to get a complete picture of airway management-related harm. Experience should improve both Safety-I and II. Experience and vigilance should also create heuristics: mental shortcuts or patterns that allow us to address problems quickly with minimal contemplation. This automaticity can help during stress, time-pressure, and complexity: by taking care of the simple things quickly and preserving cognitive bandwidth. However, heuristics can also be dangerous if we see patterns where we should not, and if we become lulled into complacency. We might wish to do the same thing every time because that is what we are “comfortable with” or “skilled at.” The danger is that we will have insufficient flexibility and dexterity (mental, physical, and verbal dexterity) when the situation with a patient at risk calls for a more nuanced approach.

We also have individual “safety barometers.” In other words, we differ in how stressful or dangerous we believe something to be. This can be influenced by prior experience, training, personality, and heuristics. One person could be overly pessimistic (“These airways are always disasters”), and one overly confident (“It’ll be fine because it usually is”), but both are deluded to some extent. For example, even if you are not an expert in all aspects of airway management (i.e., bronchoscopic intubation or supraglottic airway insertion), one of those strategies may be the safest approach in a given patient. Alternatively, you might be proficient with one technique and fallaciously assume that it will always work. As such, we recommend that you catch yourself if you utter bromides such as: “I have done this for 10 years without any problem; I’m not changing now”? or “If I have a failed airway, I’ll just keep trying while I call anesthesia or surgery.” Once again, the recent ASA closed claims database is informative. Judgment errors and complacency were common. Specifically, there was a failure to plan for difficulty; failure to assess for difficulty; failure to adapt (and the tendency to perseverate on one action), and judgment errors were compounded by further judgment errors.