Comparative study of airway management techniques with restricted access to patient airway

To determine which airway endotracheal tube (ET), Combitube (CT), or Laryngeal Mask Airway (LMA) has the shortest time to successful ventilation in three nontraditional prehospital airway scenarios.

Prospective randomized cohort study of emergency medicine (EM) residents, faculty EM physicians, and paramedics (EMT-P). Subjects were instructed to place an airway in a mannequin in three scenarios: mannequin supine under a table with head abutting a wall, mannequin sitting upright with access from behind, and mannequin lying on its side with access facing the mannequin. The number of airway placement attempts and time to successful ventilation were recorded.

Twenty-five resident physicians, 9 faculty physicians, and 22 EMT-Ps participated. No significant difference was found between the different airways in the number of attempts to successfully ventilate. EMT-Ps demonstrated significantly faster times to successful ventilation for all scenarios versus physicians (e.g., supine scenario with ET, EMT-P median time 57 seconds, physician median time 96 seconds) except for the mannequin lying on its side where there was no significant difference. The time to ventilation for all scenarios was less with the LMA versus ET or CT versus ET, except in the sitting scenario where ET and CT were comparable.

In this mannequin model of restricted airway access, LMA resulted in significantly faster times to ventilation versus ET and CT in all but one scenario. Further consideration and study using airways other than ET are warranted for situations with restricted access to the patient's airway.