The difficult airway with recommendations for management – Part 2 – The anticipated difficult airway

Abstract

BackgroundAppropriate planning is crucial to avoid morbidity and mortality when difficulty is anticipated with airway management. Many guidelines developed by national societies have focused on management of difficulty encountered in the unconscious patient; however, little guidance appears in the literature on how best to approach the patient with an anticipated difficult airway.MethodsTo review this and other subjects, the Canadian Airway Focus Group (CAFG) was re-formed. With representation from anesthesiology, emergency medicine, and critical care, CAFG members were assigned topics for review. As literature reviews were completed, results were presented and discussed during teleconferences and two face-to-face meetings. When appropriate, evidence- or consensus-based recommendations were made, and levels of evidence were assigned.Principal findingsPreviously published predictors of difficult direct laryngoscopy are widely known. More recent studies report predictors of difficult face mask ventilation, video laryngoscopy, use of a supraglottic device, and cricothyrotomy. All are important facets of a complete airway evaluation and must be considered when difficulty is anticipated with airway management. Many studies now document the increasing patient morbidity that occurs with multiple attempts at tracheal intubation. Therefore, when difficulty is anticipated, tracheal intubation after induction of general anesthesia should be considered only when success with the chosen device(s) can be predicted in a maximum of three attempts. Concomitant predicted difficulty using oxygenation by face mask or supraglottic device ventilation as a fallback makes an awake approach advisable. Contextual issues, such as patient cooperation, availability of additional skilled help, and the clinician’s experience, must also be considered in deciding the appropriate strategy.ConclusionsWith an appropriate airway evaluation and consideration of relevant contextual issues, a rational decision can be made on whether an awake approach to tracheal intubation will maximize patient safety or if airway management can safely proceed after induction of general anesthesia. With predicted difficulty, close attention should be paid to details of implementing the chosen approach. This should include having a plan in case of the failure of tracheal intubation or patient oxygenation.

Cervical spine overflexion in a halo orthosis contributes to complete upper airway obstruction during awake bronchoscopic intubation: a case report

“…It is well known that LMAD insertion can be difficult in patients with fixed flexion of the cervical spine. [13][14][15] This has been attributed to the relatively acute angle between the oral and pharyngeal axes. 13 Nevertheless, it may be reasonable to attempt to insert a supraglottic airway to restore airway patency in an emergency before release of the halo.…”

Airway management: judgment and communication more than gadgets

“…In this issue of the Journal, the Group proposes a set of recommendations designed for two different contexts, the unanticipated difficult intubation 2 and the anticipated difficult airway. 3 Contrary to what could have been expected, the Group did not recommend a given device or a specific method when approaching the difficult airway, which will probably be a disappointment for those who like simple recipes. In spite of, and probably because of, the multiplicity of new tools and approaches, safe airway management is not simpler than it was in the past.…”

“…Dans ce numéro du Journal, le Groupe propose un ensemble de recommandations conçues pour deux contextes différents, soit l'intubation difficile non prévue 2 et les voies aériennes anticipées comme difficiles. 3 Contrairement à ce que l'on aurait pu penser, le Groupe n'a pas recommandé de dispositif donné ou de méthode en particulier pour aborder des voies aériennes difficiles, ce qui va probablement décevoir les partisans des recettes simples. Malgré le grand nombre de nouveaux outils et approches, et probablement à cause de cette multiplicité, la prise en charge sécuritaire des voies aériennes n'est pas plus simple aujourd'hui que par le passé.…”

“…The guidelines contain a section on extubation, 3 and the indications for an exchange catheter in the case of a difficult intubation are well outlined. Nevertheless, problems with extubation may occur even if intubation was uneventful.…”

“…7 The previous recommendations included enthusiastic discussion of specific airway tools, such as the Combitube TM and the lighted stylets, which turned out to have a very limited future. 1 This time, the authors of the revised recommendations 2,3 are to be congratulated for refraining to endorse any particular type of equipment. All the devices available today might be replaced in the future by improved technology.…”