Comparison of Video Versus Direct Laryngoscopy: A Prospective Prehospital Air Medical Services Study

Abstract

Objective: Videolaryngoscopy (VL) in the prehospital setting remains controversial, with conflicting data on its utility. We compared C-MAC VL (Karl Storz, Tuttlingen, Germany) versus direct laryngoscopy (DL) in the prehospital setting, recording the grade of the glottic view, first pass success (FPS), overall success, and equipment functionality. Methods: We conducted a prospective observational study with a convenience sample of 49 adult patients who were intubated by flight crew nurses and paramedics using the C-MAC videolaryngoscope from April to November 2013. We compared Cormack-Lehane (CL) grades of view for DL and VL, intubation success rates, and equipment functionality. Results: CL grades 1 or 2 were obtained with 24 patients (49%) with DL and 45 patients (92%) with VL. Of the 25 patients (51%) who had a CL grade 3 or 4 view on DL, 22 of those patients (88%) converted to a CL grade 1 or 2 with VL (P < .001). There was an overall success rate of 96% and an FPS rate of 71%. The C-MAC videolaryngoscope was functional during intubation 100% of the time. Conclusion: VL improved glottic visualization compared with DL. The FPS and overall intubation success rates were similar to other published prehospital studies using VL. The C-MAC provided reliable, high-quality video despite demanding prehospital conditions.

Efficacy of Video Laryngoscopy versus Direct Laryngoscopy in the Prehospital Setting: A Systematic Review and Meta-Analysis

“…In contrast, the authors of Huebinger 2021, the largest study included in this analysis, did not specify the type(s) of VL devices utilized in their large retrospective analysis. 16 Nonetheless, the current moderator analysis comparing three studies using standard geometry (C-MAC) video laryngoscopes and two studies using hyperangulated (King Vision) video laryngoscopes 15,[17][18][19][20] showed no difference in the first-pass success rate (Table 3), although this could be due to low power. Because this link is unclear, further studies are needed to elucidate whether certain devices are better suited for the prehospital setting.…”

“…Two were randomized control trials (2013 Guyette, 2017 Ducharme), one was a prospective study (2020 Garcia-Pintos), and four were retrospective studies (2015 Jarvis, 2018 Louka, 2021 Huebinger, 2021 Lenz). [14][15][16][17][18][19][20] Three studies enrolled fewer than 100 patients (2017 Ducharme, 2018 Louka, 2020 Garcia-Pintos), while the 2021 Huebinger study involved a large population (22,132 patients). [15][16][17]20 In all the studies, a total of 6,674 patients underwent intubation via VL and 17,279 patients underwent DL (Table 1).…”

“…[14][15][16][17][18][19][20] Three studies enrolled fewer than 100 patients (2017 Ducharme, 2018 Louka, 2020 Garcia-Pintos), while the 2021 Huebinger study involved a large population (22,132 patients). [15][16][17]20 In all the studies, a total of 6,674 patients underwent intubation via VL and 17,279 patients underwent DL (Table 1). Fourteen of 21 studies reported the outcomes of interest but were excluded because they used cadaver 21 or manikin conduits and not living adult patients.…”

“…Finally, many patient characteristics were not reported in detail, which may introduce some confounding or uncontrolled factors into the analysis presented here. Most notably, only 2013 Guyette and 2020 Garcia-Pintos reported the Mallampati score or Cormack grade, 18,20 and no studies reported operator experience. It was not possible to assess for the effects of differences in airway difficulty or learning processes that may have contributed to the large heterogeneity found in this analysis.…”