Summary: Background: It is not certain whether the blade geometry of videolaryngoscopes, either a hyperangulated or Macintosh shape, affects glottic view, success rate and/or tracheal intubation time in patients with expected difficult airways. We hypothesised that using a hyperangulated videolaryngoscope blade would visualise a higher percentage of glottic opening compared with a Macintosh videolaryngoscope blade in patients with expected difficult airways. Methods: We conducted an open‐label, patient‐blinded, randomised controlled trial in adult patients scheduled to undergo elective ear, nose and throat or oral and maxillofacial surgery, who were anticipated to have a difficult airway. All airway operators were consultant anaesthetists. Patients were allocated randomly to tracheal intubation with either hyperangulated (C‐MAC D‐BLADE™) or Macintosh videolaryngoscope blades (C‐MAC™). The primary outcome was the percentage of glottic opening. First attempt success was designated a key secondary outcome. Results: We assessed 2540 adults scheduled for elective head and neck surgery for eligibility and included 182 patients with expected difficult airways undergoing orotracheal intubation. The percentage of glottic opening visualised, expressed as median (IQR [range]), was 89 (69–99 [0–100])% with hyperangulated videolaryngoscope blades and 54 (9–90 [0–100])% with Macintosh videolaryngoscope blades (p < 0.001). First‐line hyperangulated videolaryngoscopy failed in one patient and Macintosh videolaryngoscopy in 12 patients (13%, p = 0.002). First attempt success rate was 97% with hyperangulated videolaryngoscope blades and 67% with Macintosh videolaryngoscope blades (p < 0.001). Conclusions: Glottic view and first attempt success rate were superior with hyperangulated videolaryngoscope blades compared with Macintosh videolaryngoscope blades when used by experienced anaesthetists in patients with difficult airways.

Background: Transnasal videoendoscopy (TVE) is the standard of care when staging pharyngolaryngeal lesions. This prospective study determined if preoperative TVE improves the prediction of difficult videolaryngoscopic intubation in adults with expected difficult airway management in addition to the Simplified Airway Risk Index (SARI). Methods: 374 anesthetics were included (252 with preoperative TVE). The primary outcome was a difficult airway alert issued by the anesthetist after Macintosh videolaryngoscopy. SARI, clinical factors (dysphagia, dysphonia, cough, stridor, sex, age and height) and TVE findings were used to fit three multivariable mixed logistic regression models; least absolute shrinkage and selection operator (LASSO) regression was used to select co-variables. Results: SARI predicted the primary outcome (odds ratio [OR] 1.33; 95% confidence interval [CI] 1.13–1.58). The Akaike information criterion for SARI (327.1) improved when TVE parameters were added (311.0). The Likelihood ratio test for SARI plus TVE parameters was better than for SARI plus clinical factors (p < 0.001). Vestibular fold lesions (OR 1.82; 95% CI 0.40–8.29), epiglottic lesions (OR 3.37; 0.73–15.54), pharyngeal secretion retention (OR 3.01; 1.05–8.63), restricted view on rima glottidis <50% (OR 2.13; 0.51–8.89) and ≥50% (OR 2.52; 0.44–14.56) were concerning. Conclusion: TVE improved prediction of difficult videolaryngoscopy in addition to traditional bedside airway examinations.

Summary: Background: The VIDIAC score, a prospectively developed universal classification for videolaryngoscopy, has shown excellent diagnostic performance in adults. However, there is no reliable classification system for videolaryngoscopic tracheal intubation in children. We aimed to develop and validate a multivariable logistic regression model and easy‐to‐use score to classify difficult videolaryngoscopic tracheal intubation in children and to compare it with the Cormack and Lehane classification. A secondary aim was to externally validate the VIDIAC score in children. Methods: We conducted a prospective observational study within a structured universal videolaryngoscopy implementation programme. We used C‐MAC™ videolaryngoscopes in all children undergoing tracheal intubation for elective surgical procedures. We validated the VIDIAC score externally and assessed its performance. We then identified eligible co‐variables for inclusion in the PeDiAC score, developed a multivariable logistic regression model and compared its performance against the Cormack and Lehane classification. Results: We studied 809 children undergoing 904 episodes of tracheal intubation. The VIDIAC score outperformed the Cormack and Lehane classification when classifying the difficulty of videolaryngoscopic tracheal intubation, with an area under the receiver operating characteristic curve of 0.80 (95%CI 0.73–0.87) vs. 0.69 (95%CI 0.62–0.76), respectively, p = 0.018. Eight eligible tracheal intubation‐related factors, that were selected by 100‐times repeated 10‐fold cross‐validated least absolute shrinkage selector operator regression, were used to develop the PeDiAC model. The PeDiAC model and score showed excellent diagnostic performance and model calibration. The PeDiAC score achieved significantly better diagnostic performance than the Cormack and Lehane classification, with an area under the receiver operating characteristic curve of 0.97 (95%CI 0.96–0.99) vs. 0.69 (95%CI 0.62–0.76), respectively, p < 0.001. Conclusion: We developed and validated a specifically tailored classification for paediatric videolaryngoscopic tracheal intubation with excellent diagnostic performance and calibration that outperformed the Cormack and Lehane classification.

Background: An inter-incisor gap <3 cm is considered critical for videolaryngoscopy. It is unknown if new generation GlideScope Spectrum™ videolaryngoscopes with low-profile hyperangulated blades might facilitate safe tracheal intubation in these patients. This prospective pilot study aims to evaluate feasibility and safety of GlideScope^TM videolaryngoscopes in severely restricted mouth opening. Methods: Feasibility study in 30 adults with inter-incisor gaps between 1.0 and 3.0 cm scheduled for ENT or maxillofacial surgery. Individuals at risk for aspiration or rapid desaturation were excluded. Results: The mean mouth opening was 2.2 ± 0.5 cm (range 1.1–3.0 cm). First attempt success rate was 90% and overall success was 100%. A glottis view grade 1 or 2a was achieved in all patients. Nasotracheal intubation was particularly difficult if Magill forceps were required (n = 4). Intubation time differed between orotracheal (n = 9; 33 (25; 39) s) and nasotracheal (n = 21; 55 (38; 94) s); p = 0.049 intubations. The airway operator’s subjective ratings on visual analogue scales (0–100) revealed that tube placement was more difficult in individuals with an inter-incisor gap <2.0 cm (n = 10; 35 (29; 54)) versus ≥2.0 cm (n = 20; 20 (10; 30)), p = 0.007, while quality of glottis exposure did not differ. Conclusions: Glidescope^TM videolaryngoscopy is feasible and safe in patients with severely restricted mouth opening if given limitations are respected.

Summary: Introduction: Facemask ventilation is a key airway management skill but predicting difficulty can be challenging. Pre‐operative three‐dimensional face scanning may have diagnostic value. We aimed to identify interpretable facial shape features and to quantify their value for predicting difficult facemask ventilation. Methods: In this prospective observational single‐centre study, pre‐operative three‐dimensional face scans were obtained, and a structured airway assessment was performed on patients undergoing ear, nose and throat or maxillofacial surgery. The primary outcome was difficult facemask ventilation documented as an alert in the patient health record. After postprocessing, three‐dimensional face scans were fitted to an established, non‐clinical facial model to identify interpretable shape coefficients. The area under the receiver operating characteristic (AUROC) curve for the DIFFMASK score was calculated before and after enrichment with three facial shape features and the added diagnostic value was assessed using likelihood ratios. Results: Data from 398 patients were analysed. The optimism‐corrected AUROC was 0.73 (95%CI 0.65–0.80) for the DIFFMASK score and 0.74 (95%CI 0.66–0.82) for selected facial shape features. Enrichment of the DIFFMASK score with three facial shape features improved goodness of model fit (p = 0.002) and achieved an optimism‐corrected AUROC of 0.76 (95%CI 0.68–0.82). Generated face meshes with superimposed colour mapping revealed that morphological features of the nose, lower mandible, neck region and facial convexity were most predictive of difficult facemask ventilation. Discussion: Pre‐operative three‐dimensional face scans predicted difficult facemask ventilation at least as well as the DIFFMASK score. Integrating the features of three selected facial shapes enriched the DIFFMASK score and improved its diagnostic value. Digital phenotyping can complement traditional clinical assessment.