Influence of Curved Video Laryngoscope Blade Sizes and Patient Heights on Video Laryngoscopic Views: A Randomized Controlled Trial

This study aimed to compare the video laryngoscope views facilitated by curved blades 3 and 4 with an exploration of the relationship between these views and patient height. Conducted as a randomized controlled trial, this study enrolled adults scheduled for surgery under general anesthesia. Intubation procedures were recorded, and the percentage of glottic opening was measured before tube insertion. Multivariate analysis validated the impact of various factors, including blade size and patient height, on the percentage of glottic opening scores. A total of 192 patients were included. The median percentage of glottic opening scores for curved blades 3 and 4 were 100 and 83, respectively (p < 0.001). The unstandardized coefficient indicated a significant negative impact of blade 4 on the percentage of glottic opening scores (-13, p < 0.001). In the locally estimated scatterplot smoothing analysis, blade 3 exhibited a steady rise in glottic opening scores with increasing height, whereas blade 4 showed a peak followed by a decline around 185 cm. The unstandardized coefficient of height showed no significant association (0, p = 0.819). The study observed superior laryngoscopic views with blade 3 compared to blade 4. However, no significant association was found between laryngoscopic views and patient height.

Role of playback videolaryngoscope footage in improved patient care

Despite the frequency of videolaryngoscope use, to the authors’ knowledge, there are no publications exploring the role of playback video recording in real time to improve patient care. We present a patient with a difficult airway complicated by trauma during GlideScope® (Verathon Inc., Bothell, WA, USA) intubation. The injury was not recognised by any of the anaesthetic staff observing the intubation, and was only identified when playback video footage was viewed. This provided the opportunity for early ear, nose and throat surgical review prior to extubation. Airway trauma can be missed by the anaesthetist. Reviewing video playback footage at an appropriate time during the case may enable more timely recognition of airway injuries and, ultimately, improved patient care.