Canadian Airway Focus Group updated consensus-based recommendations for management of the difficult airway: part 1. Difficult airway management encountered in an unconscious patient

Abstract

Purpose Since the last Canadian Airway Focus Group (CAFG) guidelines were published in 2013, the literature on airway management has expanded substantially. The CAFG therefore re-convened to examine this literature and update practice recommendations. This first of two articles addresses difficulty encountered with airway management in an unconscious patient. Source Canadian Airway Focus Group members, including anesthesia, emergency medicine, and critical care physicians, were assigned topics to search. Searches were run in the Medline, EMBASE, Cochrane Central Register of Controlled Trials, and CINAHL databases. Results were presented to the group and discussed during video conferences every two weeks from April 2018 to July 2020. These CAFG recommendations are based on the best available published evidence. Where high-quality evidence was lacking, statements are based on group consensus. Findings and key recommendations Most studies comparing video laryngoscopy (VL) with direct laryngoscopy indicate a higher first attempt and overall success rate with VL, and lower complication rates. Thus, resources allowing, the CAFG now recommends use of VL with appropriately selected blade type to facilitate all tracheal intubations. If a first attempt at tracheal intubation or supraglottic airway (SGA) placement is unsuccessful, further attempts can be made as long as patient ventilation and oxygenation is maintained. Nevertheless, total attempts should be limited (to three or fewer) before declaring failure and pausing to consider “exit strategy” options. For failed intubation, exit strategy options in the still-oxygenated patient include awakening (if feasible), temporizing with an SGA, a single further attempt at tracheal intubation using a different technique, or front-of-neck airway access (FONA). Failure of tracheal intubation, face-mask ventilation, and SGA ventilation together with current or imminent hypoxemia defines a “cannot ventilate, cannot oxygenate” emergency. Neuromuscular blockade should be confirmed or established, and a single final attempt at face-mask ventilation, SGA placement, or tracheal intubation with hyper-angulated blade VL can be made, if it had not already been attempted. If ventilation remains impossible, emergency FONA should occur without delay using a scalpel-bougie-tube technique (in the adult patient). The CAFG recommends all institutions designate an individual as “airway lead” to help institute difficult airway protocols, ensure adequate training and equipment, and help with airway-related quality reviews.

A model to predict difficult airway alerts after videolaryngoscopy in adults with anticipated difficult airways – the VIDIAC score

“…When calculating the probabilities, the intercept value of À1 must be included (Table 3). We assessed difficult videolaryngoscopy and difficult intubation, as recommended for rating the difficulty of videolaryngoscopic intubation [5,15,16]. The six characteristics associated with a difficult airway alert after videolaryngoscopy are derived from the blade-epiglottis interaction, the view of the glottis or narrowing of the posterior laryngeal inlet.…”

Five‐year audit of adherence to an anaesthesia pre‐induction checklist

“…The primary outcome was the overall proportion of completely performed pre‐induction checklists. Secondary outcomes were changes to checklist completion adherence over the 5 years with the following explanatory variables captured for analysis: airway management difficulty (defined by the handling clinician [5, 6]) (Table 2); urgency of procedure (emergency vs. non‐emergency); time of induction (07.00–16.59 vs. 17.00–06.59); location of induction (operating theatre vs. non‐operating theatre); and care by dedicated anaesthesia teams for different surgical specialities vs. care by the emergency anaesthesia team.…”

Analysis of paralysis: understanding the role of vocal cords in facemask ventilation

“…Controversies in practice often stem from conflicting or incomplete understanding of empirical evidence. Current airway guidelines recognise an important role for complete neuromuscular blockade in ‘can't ventilate can't oxygenate’ situations, but do not explicitly discuss the role vocal cords may play, pending more evidence [23–25]. The study by Lee et al.…”