Written by Aaron Lacy
Spoon Feed
When the midline vallecular fold was engaged during laryngoscopy, intubators were more likely to obtain a Cormack-Lehane grade 1 or 2a view.
Why does this matter?
Better Cormack-Lehane grades are associated with increased intubation success. Much of airway education is spent developing laryngoscopy technique. Lifting the epiglottis to expose the glottic opening is standard during curved blade laryngoscopy – how do we best do that?
What a beautiful view
Deep to the vallecula is the hyoepiglottic ligament, and this is the structure traditionally taught to obtain the best view during laryngoscopy – “Place the blade in the vallecula.” This structure is not visible to the intubator, unlike the median glossoepiglottic fold (midline vallecular fold).
In this study, a team reviewed videolaryngoscopy attempts (n = 183) from a single academic center. In review, intubation attempts where a standard geometry blade engaged the midline epiglottic fold had a higher proportion of Cormack-Lehane Grade 1 and 2a views (96%, n = 113) compared to when it was not engaged (87%, n = 70). A better Cormack-Lehane grade is associated with a higher intubation success rate, but in this study, the authors did not report intubation success. There were more reported Grade 2b, 3 and 4 views in patients without engagement of the midline vallecular fold. Likely there was an associated decreased success rate, but we cannot know for sure nor do we know if it was any clinical significance. Of note, these studies were done with video laryngoscopy, and identifying the midline vallecular fold is more difficult during direct laryngoscopy. While there are no clinical outcomes presented in this article, the generalization of better glottic view = more likely intubation success rings true. When teaching laryngoscopy, I do point out this structure to learners, but this was the first paper I had seen formally addressing the topic. This important anatomic structure should be on your radar, and next time you are intubating, keep an eye out for it.
Another Spoonful
See this fantastic post on 5minuteairway to view what it actually looks like to engage the median vallecular fold (hyoepiglottic ligament)…or not.
Source
Engagement of the Median Glossoepiglottic Fold and Laryngeal View During Emergency Department Intubation. Ann Emerg Med. 2021 Jun 22;S0196-0644(21)00312-7. doi: 10.1016/j.annemergmed.2021.04.024.
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