Predicting the difficult airway

Abstract

### Key points The difficult airway (DA) has been defined as ‘the clinical situation in which a conventionally trained anesthesiologist experiences difficulty with face mask ventilation of the upper airway, difficulty with tracheal intubation, or both’.1 A more complete definition would include airway instrumentation (e.g. with supraglottic airway devices), direct tracheal access, and consideration of the airway at extubation. The 4th National Audit Project found that failure to assess for and identify potential difficulty, or the application of poor judgement in management planning, may contribute to a poor outcome.2 Airway assessment must go beyond carrying out a series of bedside tests; it must attempt to identify problems in each facet of airway management and incorporate these logically into a strategy. This should take into account anatomical variations, airway pathology, and previous strategies. Of great importance is the consideration of how these factors may impact on the likely success of any given technique or equipment used. The skills of the anaesthetist and the equipment available must also be accounted for. Before anaesthesia, the anaesthetist should be able to answer key questions.