Difficult and impossible intubation

Abstract

This chapter reviews the problem of the management of the difficult airway. Although the incidence of difficulty is relatively small, the consequences of mismanagement can be quite disastrous. Prediction of the difficult intubation can be made by a variety of simple clinical observations and measurements in a majority of cases. A combination of these methods is likely to lead to a lower index of false positives. Radiological assessment may be valuable if planned beforehand. Nevertheless, a number of cases of unsuspected difficulty occur. The options available in cases of difficulty are reviewed, including direct laryngoscopy using the oral and nasal routes, fibreoptic guided intubation and the use of special guiding laryngoscope blades and ancillary devices such as the laryngeal mask, the pharyngotracheal lumen airway, the Combi tube and the light wand. The technique of retrograde guided intubation is described. The surgical airway is required in certain cases of impossible intubation. Cricothyrotomy is the technique of choice in the emergency situation because it is simpler and safer to perform. Tracheostomy may be preferred in the planned case with an anticipated long-term problem. Confirmation of correct tracheal tube placement is essential. Unrecognized misplacement leads to death or severe brain damage. Simple clinical methods are generally satisfactory but are not infallible. Other methods of confirmation such as fibreoptic visualization, light wand transillumination, carbon dioxide detectors and air aspiration are discussed. A regimen for difficult airway management is produced as an algorithm.