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: Pulmonary function tests (PFTs) such as spirometry and blood gas analysis have been claimed to improve preoperative risk assessment. This systematic review summarizes the available scientific literature regarding the ability of PFTs to predict postoperative pulmonary complications (PPC) in non-thoracic surgery. Methods: We systematically searched MEDLINE, CINAHL, and the Cochrane Library for pertinent original research articles (PROSPERO CRD42020215502), framed by the PIT-criteria (PIT, participants, index test, target conditions), respecting the PRISMA-DTA recommendations (DTA, diagnostic test accuracy). Results: 46 original research studies were identified that used PFT-findings as index tests and PPC as target condition. QUADAS-2 quality assessment revealed a high risk of bias regarding patient selection, blinding, and outcome definitions. Qualitative synthesis of prospective studies revealed inconclusive study findings: 65% argue for and 35% against preoperative spirometry, and 43% argue for blood gas analysis. A (post-hoc) subgroup analysis in prospective studies with low-risk of selection bias identified a possible benefit in upper abdominal surgery (three studies with 959 participants argued for and one study with 60 participants against spirometry). Conclusion: As the existing literature is inconclusive it is currently unknown if PFTs improve risk assessment before non-thoracic surgery. Spirometry should be considered in individuals with key indicators for chronic obstructive pulmonary disease (COPD) scheduling for upper abdominal surgery.

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: Pulmonary function tests (PFTs) such as spirometry and blood gas analysis have been claimed to improve preoperative pulmonary risk assessment, but the scientific literature is conflicting. The Preoperative Diagnostic Tests for Pulmonary Risk Assessment in Chronic Obstructive Pulmonary Disease (PREDICT) study aimed to determine whether preoperative PFTs improve the prediction of postoperative pulmonary complications (PPCs) in patients with known or suspected chronic obstructive pulmonary disease (COPD) undergoing major surgery. A secondary aim was to determine whether the Global Initiative for Chronic Obstructive Lung Diseases (GOLD) classification of airflow limitation severity (grades I–IV) is associated with PPC. METHODS: In this prospective, single-center study, patients with GOLD key indicators for COPD scheduled for major surgery received PFTs. Patients with confirmed COPD (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC] ≤0.7) were included in the COPD cohort and compared with a reference cohort without COPD. We developed 3 multivariable risk prediction models and compared their ability to predict PPC: the “standard model” (medical preconditions, and sociodemographic and surgical data), the “COPD assessment model” (additional GOLD key indicators, pack-years, and poor exercise capacity), and the “PFT model” (additional PFT parameters selected by adaptive least absolute shrinkage and selection operator [LASSO] regression). Multiple LASSO regressions were used for cross-validation. RESULTS: A total of 31,714 patients were assessed for eligibility; 1271 individuals received PFTs. Three hundred twenty patients (240 with confirmed COPD: 78 GOLD I, 125 GOLD II, 28 GOLD III, 9 GOLD IV, and 80 without COPD) completed follow-up. The diagnostic performance was similar among the standard model (cross-validated area under the curve [cvAUC], 0.723; bias-corrected bootstrapped [bc-b] 95% confidence interval [CI], 0.663–0.775), COPD assessment model (cvAUC, 0.724; bc-b 95% CI, 0.662–0.777), and PFT model (cvAUC, 0.729; bc-b 95% CI, 0.668–0.782). Previously known COPD was an independent predictor in the standard and COPD assessment model. %FEV1_PRED was the only PFT parameter selected by LASSO regression and was an independent predictor in the PFT model (adjusted odds ratios [OR], 0.98; 95% CI, 0.967–.0.998; P = .030). The risk for PPC significantly increased with GOLD grades (P < .001). COPD was newly diagnosed in 53.8% of the patients with confirmed COPD; however, these individuals were not at increased risk for PPC (P = .338). CONCLUSIONS: COPD is underdiagnosed in surgical patients. Patients with newly diagnosed COPD commonly presented with low GOLD severity grades and were not at higher risk for PPC. Neither a structured COPD-specific assessment nor preoperative PFTs added incremental diagnostic value to the standard clinical preassessment in patients with known or suspected COPD. Unnecessary postponement of surgery and undue health care costs can be avoided.

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.