Variability in the criteria for a difficult intubation alert in the age of videolaryngoscopy: a scenario-based, multidisciplinary, multi-institutional provider survey

Abstract

Introduction: Our goal was to characterize further variability in how providers both define a difficult intubation and apply a difficult tracheal intubation alert. Materiala and Methods: We developed a survey describing 26 different intubation scenarios encompassing a range of clinical complexity and equipment. Scenarios included multiple factors hypothesized to impact a provider’s definition of a difficult intubation and the threshold for a difficult intubation alert. Provider responses were then assessed for variability and agreement. The survey was distributed at 2 academic medical centers, 1 in Portland, ME (1 teaching hospital, 600 beds) and 1 in Philadelphia, PA (2 teaching hospitals, 1180 total beds). Electronic surveys were sent to anesthesia and emergency medicine providers (total N=617). Providers were asked to grade the difficulty of the scenario presented and whether they would activate the difficult intubation alert in the electronic health record. Responses were pooled and summarized as a frequency (%) and analyzed by provider type and institution. Results: Providers lacked agreement about scenarios that were very difficult or when an alert should be used. This variability was similar among provider types and institutions. Providers assessed scenarios as being more difficult and were more likely to apply an alert when videolaryngoscopy was not available. Conclusions: Substantial variability was demonstrated in providers’ definition of a difficult intubation and the threshold to activate a difficult intubation alert. This variability is consistent with related findings by other groups and represents a latent patient safety threat. The availability alone of videolaryngoscopy influences a provider’s definition of a difficult intubation, resulting in the grading of a scenario as less difficult. The associated risks may be mitigated by the delineation of specific criteria for difficult intubation designation and alert activation at the hospital or health system level.

Observational analysis of criteria for a difficult airway alert

“…Although a large proportion of our difficult airway cohort were successfully managed with VL, our staff still issued a difficult airway alert. In contrast, the more recent study by Allyn et al8 reported that difficult DL rescued by VL would not warrant a difficult airway alert in the majority of providers at their centers. Our study period dated back to 2011–2016 and failed DL may no longer be as worrisome for airway providers because of increasing familiarity with VL devices, widespread availability of the devices, and an expanding scope of daily usage.…”

“…The criterion constituting a "difficult airway" to a boardcertified staff anesthesiologist who performs airway management regularly, may be different from other clinicians [8] with less experience, support, and access to advanced airway tools. Previous survey-based studies [8,15] have employed prefabricated scenarios with various combinations of airway management modalities and graded degrees of difficulty to determine the threshold for a difficult airway alert. Whereas, in our observational study the determinants for assigning a difficult airway alert were derived from real scenarios encountered by our staff.…”

“…Recent airway studies have reported increasing use of VL [7,8] and associated decreased rates of difficult laryngoscopy [7] . A large multicenter study found that VL was the most frequently chosen rescue technique (69%) after failed DL, and there was a 50% increase in usage of VL as a rescue device over a 10-year period (2004-2013) [14] .…”

“…Although the difficult airway societies and airway focus groups endorse accurate documentation of the difficult airway and the use of alerts as an important component in advancing patient safety,4–6 there is no universally accepted criteria for assigning a difficult airway letter or alert. Furthermore, the evolving role of videolaryngoscopy (VL) and its impact on the difficult airway7 may obfuscate the criteria for what specific clinical scenarios warrant a difficult airway alert 8,9. A recent article by Allyn et al8 on variability in the criteria for a difficult intubation alert found that the threshold for issuing an airway alert was affected by the type of airway provider (anesthesiologist vs. nonanesthesiologist) and the availability of VLs.…”

“…Furthermore, the evolving role of videolaryngoscopy (VL) and its impact on the difficult airway [7] may obfuscate the criteria for what specific clinical scenarios warrant a difficult airway alert. [8,9] A recent article by Allyn et al [8] on variability in the criteria for a difficult intubation alert found that the threshold for issuing an airway alert was affected by the type of airway provider (anesthesiologist vs. nonanesthesiologist) and the availability of VLs. Further to this they also reported that VL use at their center had increased from 62% to 91% of all adult intubations over the 2-year study period.…”