Preoperative Airway Evaluation
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Purpose of Review
This paper provides an updated review on preoperative airway assessment, the factors that are used to predict a difficult airway, and whether difficulty can be accurately predicted.
Traditional history and examination features have focused on prediction of difficult intubation, but recent studies attempt to predict difficulty with other aspects of managing the airway including bag-mask ventilation, supraglottic airway (SGA) ventilation, and front-of-neck access. A recent Cochrane review confirms that traditional examination findings lack diagnostic accuracy for detection of difficult airways. There is promise in the use of airway imaging techniques including endoscopy and ultrasound, for preoperative prediction of difficult airways.
Despite thorough assessment, a significant percentage of airway difficulties will continue to be unanticipated, and there is no single test, or combination of tests, that can accurately and reliably predict a difficult airway. The anesthesiologist should be prepared for unanticipated difficulty, as prediction remains imprecise. Further studies are required to refine the specific parameters and measurements expected for newer imaging modalities which might be beneficial, including airway ultrasound and endoscopy.
KeywordsDifficult intubation Difficult ventilation Difficult bag-mask ventilation Difficult supraglottic airway ventilation Difficult airway Airway assessment Airway ultrasound Airway endoscopy Airway examination Bedside airway tests
Compliance with Ethical Standards
Conflict of Interest
Louise Ellard and David T. Wong declare that they have no conflict of interest.
Human and Animal Rights and Informed Consent
This article does not contain any studies with human or animal subjects performed by any of the authors.
Papers of particular interest, published recently, have been highlighted as: • Of importance •• Of major importance
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