Avoid common mistakes on your manuscript.
To the Editor,
We thank Bhakta et al.1 for their interest in our work2 and for emphasizing the importance of the epiglottis–blade interaction in the management of difficult tracheal intubation.
Our study compared a curved-blade videolaryngoscope with the Vie Scope® (Adroit Surgical LLC, Oklahoma City, OK, USA) as a straight-blade anterior commissure laryngoscope necessitating bougie-facilitated intubation in a two-step approach. Although the Vie Scope is a conventional laryngoscope that provides a direct view of the glottis, it has been suggested as a substitute for videolaryngoscopes, for example in emergency medicine.
The idea behind our studies was to test the novel Vie Scope device against the clinical standards, Macintosh laryngoscope3 and Macintosh videolaryngoscope,2 which are typically used for laryngoscopy in many departments. In our opinion, this was the most reasonable comparison for evaluating efficacy and safety of this novel device.
Bhakta et al.1 highlight a crucial point that restricted glottis movement might substantially impair the view of the glottis during laryngoscopy and that indirect or direct glottis lifting plays a key role in difficult airway management. While Macintosh videolaryngoscopy relies on indirect epiglottis lifting by point pressure on the hyoepiglottic ligament in the vallecula, straight-blade techniques rely on direct epiglottis lifting by placing the blade’s tip beneath the epiglottis and close to the anterior commissure. Nevertheless, it has been proposed that direct epiglottis lifting can also be performed with laryngoscopy approaches other than straight-blade techniques (e.g., with Macintosh blades), but this is currently underreported.4 Most recently, the first prospectively developed universal classification for videolaryngoscopy (the VIDIAC score) has been published including these important aspects of impaired epiglottis movement and direct epiglottis lifting for the grading of difficult videolaryngoscopic intubation.5
We acknowledge that we compared a two-stage bougie-facilitated approach against a one-stage approach, but this reflects the devices’ intended uses and we believe that any new device should show its noninferiority against current clinical practice.
We agree that knowledge gaps regarding the Vie Scope remain, and we encourage Bhakta et al. to conduct further studies comparing the Vie Scope against videolaryngoscopes with different types of blades (e.g., straight or hyperangulated) and also against other bougie-facilitated approaches. This would add to our knowledge of anterior commissural laryngoscopy and provide further valuable insights into airway management.
References
Bhakta P, Karim HM, Mandal M, O’Brien M. Comparing devices for managing the difficult airway. Can J Anesth 2024; https://doi.org/10.1007/s12630-023-02626-9.
Petzoldt M, Grün C, Wünsch VA, Bauer M, Hardel TT, Grensemann J. Vie Scope® versus videolaryngoscopy in expected difficult airways: a randomized controlled trial. Can J Anaesth 2023; 70: 1486–94.
Petzoldt M, Engels Y, Popal Z, et al. Elective Tracheal Intubation With the VieScope-A Prospective Randomized Non-inferiority Pilot Study (VieScOP-Trial). Front Med (Lausanne) 2022; 9: 820847
Oh JY, Lee JH, Kim YY, Baek SM, Jung DW, Park JH. A comparative study of glottis visualization according to the method of lifting the epiglottis in video laryngoscopy: indirect and direct lifting methods. Anesth Pain Med (Seoul) 2021; 16: 196–200.
Kohse EK, Siebert HK, Sasu PB, et al. A model to predict difficult airway alerts after videolaryngoscopy in adults with anticipated difficult airways—the VIDIAC score. Anaesthesia 2022; 77: 1089-1096
Disclosures
Martin Petzoldt has received a study grant from Verathon Inc., Bothell, WA, USA. Tim T. Hardel has received research support from Drägerwerk; Jörn Grensemann has received research support from Ambu and ETView, and consultant fees from Drägerwerk and GE HealthCare. The other authors declare no conflicts of interests.
Funding statement
Open Access funding enabled and organized by Projekt DEAL. The study was funded from departmental resources with the Vie Scopes kindly provided free of charge by the distributor.
Editorial responsibility
This submission was handled by Dr. Stephan K. W. Schwarz, Editor-in-Chief, Canadian Journal of Anesthesia/Journal canadien d’anesthésie.
Author information
Authors and Affiliations
Corresponding author
Additional information
Publisher's Note
Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.
Rights and permissions
Open Access This article is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, which permits any non-commercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc/4.0/.
About this article
Cite this article
Petzoldt, M., Grün, C., Wünsch, V.A. et al. In reply: Comparing devices for managing the difficult airway. Can J Anesth/J Can Anesth 71, 156–157 (2024). https://doi.org/10.1007/s12630-023-02627-8
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12630-023-02627-8