Point | Counterpoint – DL Should Be Learned Before VL

August 12, 2024

Written by Aaron Lacy

Spoon Feed
Today we are looking at an opinion piece published in Chest where the authors provide an argument that DL should be learned prior to VL.

Take the direct route…
VL vs DL – Has anyone ever talked about that before? These authors make the argument that DL is not dead, and, in fact, is the building block for learning VL.

Key points include:

• Despite evidence showing increased first attempt success in VL vs DL, worldwide, 80% of emergency tracheal intubations are done with DL.
• Mechanical forces applied during DL are the same to achieve glottic view during VL (standard geometry presumed here, although not specified); therefore, skills from DL repetitions inform expert VL technique
  • They argue the interplay between learning to obtain a view and adjustments of the blade are degraded when using VL, because it is too easy to obtain a view in VL.
• Even though VL device failure/unavailability in high-income countries is rare, it still happens, and we need to be prepared. We still mandate teaching how to do a cric, even though that is a rare event, right?
• You can teach DL with VL blades, just have the screen facing the instructor, who can provide real time coaching.
• DL is a potentially lifesaving technique, and there is no substitute for teaching and understanding proper positioning, progressive epliglottoscopy, and laryngoscopy.

How will this change my practice?
This opinion piece doesn’t change my practice. We all have bias, and I acknowledge mine. To start, I am not someone who thinks we don’t have to learn DL. However, as not only an emergency physician but an educator, I don’t follow the same logic as the authors. Their point that the mechanical forces of DL inform expert VL is backwards to me. If the same, why not, like learning ultrasound, get a high-definition, real-time view of what adjustments change your glottic exposure? In this way, expert VL techniques can help inform expert DL technique, and novices can build psychomotor pathways with immediate real-time feedback. They also discuss because VL is “easy” to obtain a view, standard airway care (proper positioning, progressive laryngoscopy, bimanual laryngoscopy, etc) will be degraded. That simply is a failure of instruction and standard of care. Blade type does not obviate the need for proper patient positioning and laryngoscopy technique. I personally prefer my novice learners to use VL first to build psychomotor pathways, get feedback from a coaching laryngoscopist (the attending), and – after they build confidence and skills – work on gaining DL expertise.

Source
POINT: Direct Laryngoscopy: The Building Block to Airway Expertise? Yes. Chest. 2024 Jun;165(6):1296-1297. doi: 10.1016/j.chest.2023.12.035. PMID: 38852966.