99 A Comparison of Direct Versus Video Laryngoscopy for Difficult Airway Patients in the Emergency Department: A National Emergency Airway Registry Study

Abstract

Video laryngoscopy (VL) use has increased over the past few years, with 39% of emergency department (ED) intubation first attempts using VL as of 2012. Although single-center observational studies have demonstrated higher intubation success when VL is used over direct laryngoscopy (DL), randomized controlled trials, mostly from intensive care units, have failed to show superiority of VL. The primary goal of our study was to compare first-pass success rates between VL and DL in ED patients with predicted difficult airways. We hypothesized that VL would be superior to DL for first-pass intubation success in patients with difficult airways. Design - This was a secondary analysis of prospectively collected observational data in the National Emergency Airway Registry from January 1, 2016 to December 31, 2017. Setting - Data were entered into an online data entry tool (StudyTRAX, Inc.). Variables included age, indication, methods, medications used, devices, adverse events, and outcomes. 90% recording compliance was required for data to be included in the registry. Participants - All pediatric and adult patients with an attempted intubation in the ED, defined as insertion of the device into the mouth past the alveolar ridge regardless of success, were included in the study. Observations - The primary outcome measure was the rate of first-pass success with either DL or VL for various difficult airway characteristics, including patients who were anticipated to be difficult by the intubator, greater than normal body habitus, reduced neck mobility, Mallampati score greater than 2, reduced mouth opening, thyromental distance less than 2 fingers, airway obstruction present, facial trauma, or blood or vomit in the airway. Secondary variables included patient characteristics, pre-intubation hemodynamics, oxygenation status, indications, and adverse events. A total of 12,722 intubations were included in the study. 63 intubations were missing an entry for first-pass success. The overall first-pass success rate for intubations with DL was 3485/4304 (81.0%, 95% CI 79.8-82.1%) compared to 7489/8320 (90.0%, 95% CI 89.3- 90.6%) for VL. VL also had a higher first-pass success rate for all difficult airway characteristics compared to DL. Among the 4201 patients anticipated to be difficult airways, 889/1249 (71.2%, 95% CI 68.5-73.6%) were successfully intubated on first pass with DL compared to 2456/2943 (83.5%, 95% CI 82.1-84.8%) with VL. VL was used more than twice as often as DL. We observed a higher overall first-pass success rate with VL. Furthermore, VL also had a higher first-pass success rate for patients anticipated to have difficult airways or who had specific difficult airway characteristics. Our study is limited by the observational nature of the data as well as possible reporting bias.