Canadian Journal of Anesthesia

, 48:795 | Cite as

Learning to exchange an endotracheal tube for a laryngeal mask prior to emergence

  • Michael S. Stix
  • Carl J. Borromeo
  • Guy J. Sciortino
  • Paul D. Teague
Cardiothoracic Anesthesia, Respiration and Airway



To present a stepwise training method, first critiquing laryngeal mask (LM) insertion difficulty and malpositioning, then learning how to exchange an endotracheal tube (ETT) for a LM during emergence from anesthesia.


“Learning phase:” sixty adults were enrolled in a preliminary study in which ETT / LM exchange was not performed — only LM insertion difficulty and malpositioning in the presence of an oral ETT were evaluated. After induction of anesthesia and oral intubation, a classic LM size 4 was inserted using the standard recommended technique. Number of insertion attempts and fibreoptically determined malpositions were recorded. “ETT / LM exchange phase:” we performed airway exchange in 50 patients selected from our individual practices.


“Learning phase:” the LM was satisfactorily positioned, on first attempt, in 95% of cases. With multiple insertion attempts it was possible to place the LM in all 60 intubated patients. Unsuccessful initial placement of the LM was always due to insufficient insertion depth (5%). When fully inserted into the hypopharynx, the epiglottis could be viewed fibreoptically in 13% of cases. “ETT / LM exchange phase:” the LM was inserted successfully in all 50 patients on first attempt. No complications occurred during any exchange.


We found it is easy to learn how to insert a LM in the presence of an oral ETT The most serious malposition, occurring in 5% of first attempts, was insufficient insertion depth. The only other malposition we encountered, fibreoptic visualization of the epiglottis, is not likely to result in complete airway obstruction following endotracheal extubation under anesthesia.


Laryngeal Mask Airway Airway Exchange Tracheal Extubation Insertion Depth Insertion Attempt 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Apprendre à remplacer un tube endotrachéal par un masque laryngé avant le retour à la conscience



Présenter une méthode d’apprentissage progressif, comprenant d’abord la formulation de critiques sur les difficultés d’insertion et la malposition du masque laryngé (ML), puis l’apprentissage de l’échange d’un tube endotrachéal (TET) pour un ML pendant le retour à la conscience après l’anesthésie.


“Phase d’apprentissage” : 60 adultes ont été recrutés pour une étude préliminaire au cours de laquelle l’échange TET / ML n’a pas été réalisé, mais où seulement la difficulté d’insertion et la malposition du ML, en présence d’un TET oral, ont été évaluées. Après l’induction de l’anesthésie et l’intubation orale, un ML typique de taille 4 a été inséré selon la technique standard recommandée. Le nombre d’essais nécessaires à l’insertion et de malpositions déterminées par fibroscopie a été noté. “Phase d’échange TET / ML” : l’échange a été réalisé chez 50 patients choisis parmi notre clientèle.


“Phase d’apprentissage” : le ML a été mis en place de façon satisfaisante dans 95% des cas. Après de multiples essais, il a été possible d’insérer le ML chez les 60 patients intubés. Une malposition initiale du ML était toujours causée par une insertion insuffisamment profonde (5 %). Lorsque le ML était complètement inséré dans l’hypopharynx, on pouvait voir l’épiglotte par fibroscopie dans 13% des cas. “Phase d’échange TET / ML” : le Ml a été inséré avec succès chez les 50 patients au premier essai et aucune complication n’est survenue.


Nous avons constaté qu’il est facile d’apprendre à insérer un ML en présence d’un TET oral. La malposition la plus sérieuse, survenue dans 5 % des cas au premier essai, a été une insertion insuffisamment profonde. La seule autre malposition notée, la visualisation fibroscopique de l’épiglotte, ne risque pas de provoquer d’obstruction complète des voies aériennes à la suite de l’extubation endotrachéale sous anesthésie.


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Copyright information

© Canadian Anesthesiologists 2001

Authors and Affiliations

  • Michael S. Stix
    • 1
  • Carl J. Borromeo
    • 1
  • Guy J. Sciortino
    • 1
  • Paul D. Teague
    • 1
  1. 1.Department of AnesthesiologyLahey ClinicBurlingtonUSA

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