Questions about the macintosh laryngoscope and technique of laryngoscopy.

Location of the epiglottis and larynx is usually easy. In Tracheal intubation for administration of anaesthesia addition, the optimum depth of insertion is determined was rarely used until it could be performed under automatically by the valecula. However, there is a vision. Within a few years of the first description of significant incidence of failure to see the larynx with tracheal intubation by direct laryngoscopy [1], tracheal the Macintosh laryngoscope [8]. Furthermore, there intubation under vision was used regularly to provide are now six series [9] in which optimum straight larynmaximum airway security for the anaesthetized goscopy techniques have facilitated a view of the patient. These early tracheal intubations involved the larynx in most patients in this situation. It seems that use of straight laryngoscopes, but few authors gave the price to be paid for the ease of use of the Macintosh details of their techniques. However, Jackson [2] technique in most patients, is more frequent failure stressed the importance of keeping the laryngoscope to visualize the larynx than is the case with straight lateral to the tongue (paraglossal technique). Magill [3] laryngoscopy techniques. Because difficult tracheal also recognised the importance of inserting the larynintubation is a major cause of serious complications goscope from the right side of the tongue, and went in anaesthesia (vide infra), it is probable that exclusive on to refine the technique, when difficulty was exuse of the Macintosh laryngoscope is responsible for perienced, by keeping the laryngoscope in the right avoidable morbidity and mortality, with serious conside of the mouth throughout laryngoscopy and trachsequences for patients, individual anaesthetists, and eal intubation. Others subsequently recommended [4, healthcare costs. 5] or illustrated [6] use of the straight laryngoscope in It is time to reassess the role of the Macintosh the centre of the mouth, suggesting that it made technique. Important questions are: identification of landmarks easier. This may be true in some patients, but in the more difficult case it renders 1 What are the implications of the failure rate of the the straight laryngoscope technique more difficult, Macintosh technique? more traumatic, and more likely to fail. This failure to 2 What are the advantages and limitations of blind adhere to the details of Magill’s recommendations techniques of intubation, when the Macintosh techset the scene for the introduction of the Macintosh nique fails? laryngoscope [7]. At present, straight laryngoscopes 3 Why is failure with the Macintosh laryngoscope are rarely used for tracheal intubation of adults in inevitable in some patients? 4 Can we use straight laryngoscope techniques to Europe, and skill in the technique has been lost. Furreduce the morbidity of tracheal intubation? thermore, it is difficult to rediscover these skills, since 5 If so, what are the implications for clinical practice many textbooks give the erroneous impression that and training? straight laryngoscopes should be used in the midline. The Macintosh curved laryngoscope [7] was introduced in conjunction with a technique of indirect What are the implications of the failure rate of elevation of the epiglottis. It requires less effort to the Macintosh technique? master the Macintosh than straight laryngoscopy techniques. Although the Macintosh laryngoscope is inBecause the Macintosh laryngoscope is used almost serted lateral to the tongue, the tongue is moved to the exclusively for tracheal intubation of adults in Europe, complications of tracheal intubation can be regarded left and the laryngoscope is advanced in the midline.