VL vs. DL – Better View and More First-Pass Success?

May 8, 2023

Written by Seth Walsh-Blackmore

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A post hoc analysis of two RCTs found greater adjusted odds of a favorable glottic view and first-attempt success – with suboptimal glottic view – when using video laryngoscopy (VL) vs. direct laryngoscopy (DL).

Why does this matter?
First pass success minimizes complications of emergent intubation. Though quality cohort data suggest  VL improves first-pass success in the ED, the debate continues. This analysis compares the most important steps of the procedure: glottic view and tube passage.

I can’t see cords; just the need for a randomized trial.
This post hoc analysis of the BOUGIE and PREPARE II trials included 1319 VL and 467 DL intubations in the ED or ICU. The authors compared VL to DL for Cormack-Lehane (CL) grade of view and first-attempt success, defined as one look and one attempt.

Twenty-two percent more VL vs. DL attempts experienced a grade 1 view (70.4% vs. 48.2%, respectively). In a regression model, the adjusted odds ratio (aOR) for a favorable view when using VL vs. DL was 3.14* (95%CI 2.47- 3.99).

Overall, 11.0% more VL vs. DL attempts experienced first-pass success (83.2 vs. 72.2%, respectively). For grade 1 CL view, there was no difference in first-pass success between VL and DL. However, with worsening glottic views (CL grades 2-4), first-pass success was consistently higher with VL vs DL. This article adds to evidence that VL is superior in emergent intubations. However, it has the limitations of a post hoc analysis; namely, device selection was operator dependent and non-random, introducing the possibility of confounding by indication. An ongoing RCT should bring clarity on this point soon.

Reviewed and edited by Clay Smith

Source
Laryngoscopy and Tracheal Intubation: Does Use of a Video Laryngoscope Facilitate Both Steps of the Procedure? Ann Emerg Med. 2023 Apr 5;S0196-0644(23)00126-9. doi: 10.1016/j.annemergmed.2023.02.016. Online ahead of print.

Editor’s note: We sometimes lose sight of what an odds ratio (OR) like 3.14 means. An OR of 1 means no difference. An OR of 2 would mean 100% greater odds. So, an OR of 3.14 means 214% greater odds of a grade 1 view using VL vs. DL. I don’t know if you’re a betting person, but I know which one I’d pick. ~Clay Smith