Welcome to the thirty-fifth episode of AEM Early Access, a FOAMed podcast collaboration between the Academic Emergency Medicine Journal and Brown Emergency Medicine. Each month, we'll give you digital open access to an recent AEM Article or Article in Press, with an author interview podcast and suggested supportive educational materials for EM learners.

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DISCUSSING (CLICK ON TITLE FOR FULL TEXT, OPEN ACCESS THROUGH FEBRUARY 29):

Laryngoscopy Compared to Augmented Direct Laryngoscopy in Adult Emergency Department Tracheal Intubations: A National Emergency Airway Registry (NEAR) Study. Calvin A. Brown III MD, Amy H. Kaji MD, Andrea Fantegrossi MPH, Jestin N. Carlson MD, Michael D. April MD, DPhil, Robert W. Kilgo MD Ron M. Walls MD on behalf of the National Emergency Airway Registry (NEAR) Investigators

LISTEN NOW: INTERVIEW WITH AUTHOR CALVIN BROWN, MD

ABSTRACT

Objective: To compare first attempt intubation success using direct laryngoscopy augmented by laryngeal manipulation, ramped patient positioning and use of a bougie (A-DL) with unaided video laryngoscopy (VL) in adult emergency department intubations.

Methods: Secondary analysis of a multicenter prospective observational database of emergency department intubations from the National Emergency Airway Registry (NEAR). We compared all VL to seven exploratory permutations of A-DL using multivariable regression (MVLR) models. We further stratified by blade shape into hyper-angulated VL (HA-VL) and standard-geometry VL (SG-VL). We report differences in first-attempt intubation success and peri-intubation adverse events with cluster-adjusted odds ratios (OR) with 95% confidence intervals (CI). We report univariate comparisons in patient characteristics, difficult airway attributes and intubation methods using descriptive statistics and OR with 95% CI.

Results: We analyzed 11,714 intubations performed during Jan 1, 2016 through December 31, 2017. Of these encounters, 6,938 underwent orotracheal intubation with either A-DL or unaided VL on first attempt. A-DL was used first in 3,936 (56.7%, 95%CI, 46.9-66.5) versus unaided VL in 3,002 (43.3%, 95%CI 33.5-53.1). Of the A-DL first intubations 1,787 (45.4%) employed ramped positioning alone,1,472 (37.4%) had ELM, and 365 (9.3%) used a bougie. RSI was the most common method used in 5,602 (80.8%, 77.0-84.5) cases. First-attempt success was significantly higher with all VL (90.9%, 95%CI, 88.7-93.1) versus all A-DL (81.1%, 95%CI, 78.783.5) despite the VL group having more patients with reduced mouth opening, neck immobility and an initial impression of airway difficult. Multivariable regression analyses controlling for indication, method, operator specialty and year of training, center clustering and all registryrecorded difficult airway predictors revealed first-attempt success was higher with all unaided VL compared with any A-DL (AOR 2.8, 95%CI 2.4-3.3), DL with bougie (AOR 2.7, 95%CI 2.1-3.5), DL with ELM (AOR 1.8, 95%CI 1.5-2.2), DL with ramped positioning (AOR 2.8, 95%CI 2.3-3.3) or DL with ELM plus bougie (AOR 2.8, 95%CI 2.3-3.3). Subgroup analyses of HA-VL and SGVL compared with any A-DL yielded similar results (AOR 3.2, 95%CI 2.6-3.0 and AOR 2.4, 95%CI 1.9-3.0, respectively). The propensity score adjusted odds for first-attempt success with video laryngoscopy was also 2.8 (95%CI, 2.4-3.3). Fewer esophageal intubations were observed in the VL cohort (0.4% vs. 1.3%, adjusted OR 0.2, 95%CI, 0.1-0.5).

Conclusion: Video laryngoscopy used without any augmenting maneuver, device or technique results in higher first attempt success than does direct laryngoscopy that is augmented by use of a bougie, external laryngeal manipulation, ramping, or combinations thereof.