Among all emergency care providers, competency in managing the airway is essential to managing patients who are acutely ill or injured. Generally, the situation is emotionally charged, the circumstance is urgent, and the stakes are high. The practitioner must know what to do and when to do it.
Having committed the past two and a half decades of our professional careers to teaching airway management, it still strikes us how difficult it is to effectively teach airway management skills and to have students demonstrate learning. So much so that in the mid 1990s, we (with Dr. Bob Schneider) created a dedicated educational program for emergency practitioners to provide a comprehensive immersion experience in emergency airway management, with a special emphasis on the identification and management of the difficult and failed airway.
This program, which has trained more than 3,000 emergency providers, has undergone progressive improvement and innovation, and is now called The Difficult Airway Course: Emergency. It’s one of a family of educational programs that now includes The Difficult Airway Course: EMS, and The Difficult Airway Course: Anesthesia.
In the development of these programs, we recognized the importance of both cognitive and skill components in training clinicians on airway management, and incorporated those components into a comprehensive and effective curriculum. So what does it take to successfully educate EMS providers on airway management?
How We Apply Learning
When a clinician encounters an airway emergency, each step of the assessment and intervention process is potentially challenging. The cognitive piece of response—
the “what”—involves a multitude of parameters, including knowing the anatomy, physiology and pathophysiology of the airway; knowing how to evaluate the airway; understanding the what, how and when of medications used in airway management; and deciding the best method of management and the best time to intervene.
The competent, well-trained provider has the ability to apply this knowledge to actual cases in such a manner that the most appropriate action is taken. Thus, the training must involve acquiring the technical and cognitive skill sets needed to manage the airway and knowing how to rescue the situation (and the patient) “if the wheels come off.”
Essentially, practitioners deal with critical incidents with one of two basic mechanisms—by either a rule-based solution or a knowledge-based solution.1,2
To reach a rule-based solution, the practitioner recognizes the event for what it is.
They identify and apply a solution that experience has shown will likely be useful in solving the problem. Recognizing the event involves a process called “similarity matching” or “pattern recognition,” which means we recognize characteristics of a current event as being similar to those of past events. This process assumes they’ve had sufficient experience with both the situation and the application of the rule to immediately recognize the problem and to know which rule to apply.
This ability constitutes what’s called “expertise.” Unfortunately, difficult and failed airways are encountered infrequently in practice, and the individual experiences of the vast majority of practitioners is unlikely to have been sufficient to earn them “expert” status.
A knowledge-based solution is a ground-up, first-principles strategy whereby the practitioner, without substantial past experience with similar situations, attempts to find an appropriate solution. Not surprisingly, such strategies are time-consuming, and, if forced under pressure, are more likely to result in failure.
However, most emergency airway managers don’t have sufficient clinical experience with difficult airways to have in their minds a rule-based, organized approach to these airway dilemmas, nor the time to build one from first principles. For this reason, a variety of tools, such as mnemonics and pre-formulated airway algorithms, have been crafted to aid rapid decision-making and increase the odds of making appropriate treatment decisions.
Mnemonics are useful in guiding the practitioner in rapidly evaluating the airway for difficulty with respect to management options, including bag-mask ventilation (BMV), the use of extraglottic devices (EGDs), laryngoscopy and intubation, and surgical airway management. Two of the mnemonics used in The Difficult Airway Courses are shown in Figure 1.3
Devices to Discuss
Some techniques and devices for airway management are so established that they constitute the standard of care and must be taught in any program. Examples include BMV, laryngoscopy and orotracheal intubation, and cricothyrotomy. That’s not to say they must be taught as first-line interventions, but simply that they must be taught within the scope of the educational program.
The marketplace is flooded with airway management devices. The reason is clear: Airway management is difficult, and the ideal device that’s easy to use and guarantees near 100% success has yet to be invented. So it’s left up to those with expertise in the field to select the devices perceived to deliver an advantage over what currently exists—decisions that are, where possible, backed up by good scientific evidence. Some of these devices and techniques include the intubating stylet, EGDs, rigid and semirigid optical stylets, video laryngoscopes, and flexible fiber optics.
Sometimes, a device or technique has particular relevance to the practice environment of one audience and not another. The best example is the prehospital environment, where sterilization of reusable devices isn’t ordinarily possible, rendering an advantage to single-use devices (e.g., disposable versus reusable EGDs, or the GlideScope® Cobalt instead of the GlideScope Ranger).
Importantly, there are devices that are not taught because they may require high-frequency use to maintain competence, are too expensive or confer little advantage over simpler devices or techniques.
Part of the reason health-care providers find airway management stressful is that some of the fundamental skills are difficult to master and, generally, poorly taught.
BMV is one of those skills. It’s at least as difficult to master as laryngoscopy and intubation. It requires a substantial amount of manual dexterity and practice to become proficient, and remain proficient. Because of this skill difficulty, it’s worth considering why BMV hasn’t been relegated to a subsidiary position in the basic airway management of the unresponsive patient in favor of easily taught and learned EGDs, such as the Combitube, King LTS or the LMA Fastrach.
Laryngoscopy and orotracheal intubation together are renowned as a difficult technique to master. Roughly 50 orotracheal intubations are necessary to establish “competence” in the technique, defined as a 90% chance of success.4 It’s a highly nuanced technique that requires detailed step-by-step teaching. The program of instruction must emphasize those nuances (e.g., the importance of exerting pressure on the hyoepiglottic ligament when performing a curved blade intubation, employing an intubating stylet to facilitate intubation, how BURP is correctly performed). Even the specific motions of the endotracheal tube during insertion are critical to master.
An educational program must identify the “tricks” that enhance success—that little maneuver that makes “the last 5%” successful. At the same time, the program must reinforce true principles of management (e.g., leave the dentures in to bag ventilate, but remove them to intubate) and debunk well-established but incorrect dogma (e.g., smearing K-Y Jelly on a beard makes BMV easier).
Virtually all the devices mentioned in the “Devices” section require detailed step-by-step instruction with respect to patient selection, standard technique and modifications in specific situations to achieve success—some more so than others. For example, optical stylets and video laryngoscopes may be of limited value in the bloody airway, and it’s easier to teach (and learn) the provision of gas exchange to an unresponsive patient with a King LTS than to use BMV. Instruction on BMV is necessarily more intense than Combitube insertion because the former is a more difficult technique to master.
It’s clear from the literature that no single method of education—classroom lecture alone, case studies alone, skills labs alone—adequately teaches complex cognitive and technical skills, such as airway management, and is consistent with our experience over decades of education of health-care providers at all levels. A method of instruction that integrates didactic teaching, case studies and skills development provides the best educational experience.
Simulation has emerged as a key educational resource in areas where cognitive and technical factors combine to force the participant to judge the best course of action. The evidence from the literature suggests that simulation enhances performance and that this performance enhancement is sustained.5 Evidence also supports the idea that simulation enhances skills development in airway management, reducing the need for actual live patient training.6,7
Gas exchange is fundamental to airway management. Programs that teach airway management must embrace this dictum and design objectives to achieve this program goal. Airway management has important and interrelated cognitive and skill components. Thus, educational programs that provide an element of didactic teaching, case studies that apply and reinforce the didactic content, and skills teaching in a realistic simulated environment are best suited to the acquisition and long-term retention of airway-management skills.
Disclosure: Drs. Murphy and Luten have reported no conflicts of interest. Dr. Walls has reported receiving honoraria from Verathon Inc. for a speaking engagement in 2007.