A prospective randomized high fidelity simulation center based side-by-side comparison analyzing the success and ease of conventional versus new generation video laryngoscope technology by inexperienced laryngoscopists

Introduction.  Indirect video laryngoscopes are altering the landscape of airway management. The primary aim of this prospec-tive randomized patient simulator analysis was to objectively compare video laryngoscopes to standard airway management techniques in novice users.

Methods. "First year medical students were exposed to high-fidelity simulated normal and difficult airway scenarios while using an array of indirect video laryngoscopes (e.g., the GlideScope, McGRATH or Pentax AWS-100) that were compared to Macin-tosh laryngoscope and fiberoptic bronchoscope (i.e., historic gold standards for normal and difficult airways, respectively)." Results. In the normal airway scenario, the best glottic view (both subjective and objective) was obtained with the video laryngoscopes and intubation success rates were highest with the video laryngoscopes (100% success rate for each device) and Macintosh (80%). In the difficult airway scenario, the best glottic view was achieved with all video laryngoscopes and the fiberoptic bronchoscope; however, tracheal intubation was best achieved with the video laryngoscopes (100% success rate for each device) whereas the success rate with the bronchoscope was only 36%.

Discussion. Our findings support the use of the GlideScope, McGRATH, or Macintosh laryngoscopes for novice users mana-ging a normal airway. When managing the difficult airway, there was no difference between any video or Macintosh laryngosco-pe in the time to successfully intubate the trachea. Over time, study participants demonstrated learned behavior as they became more facile with all devices. When comparing the video laryngoscopes, all three performed similarly overall and proved useful in the hands of novice users. Regardless of airway difficulty, the fiberoptic bronchoscope yielded the worst results.

airway, airway manage-ment, airway equipment, patient simu-lation, success, tracheal intubation

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