Comparison of four methods of endotracheal tube passage in simulated airways: There is room for improved techniques

Abstract

Objective: Endotracheal intubation requires laryngoscopy followed by passage of the endotracheal tube (ETT). Tube passage can be difficult, but there is little evidence to support which adjunct for tube passage is most effective.

Methods: The four tube passage adjuncts tested were the naked ETT, stylet ETT, railroaded bougie and preloaded bougie. Participants completed pre- and post-test surveys identifying demographics, experience and method preference. After instruction, participants completed eight intubations on manikins with 'easy' and 'difficult' airways.

Results: One hundred and seventeen practitioners who were experienced emergency medicine physicians, anaesthesiologists and out-of-hospital providers completed 936 total ETT attempts. For the 'difficult' airway, the percentage first pass success (95% confidence interval [CI]) for the naked ETT was 30.8% (23.1-39.7%). This was significantly lower than the stylet ETT (95.7% [86.6-100%]), the railroaded bougie (75.2% [63.8-86.6%]), or the preloaded bougie (89.7% [79.7-99.7%]). On difficult airways, the median (interquartile range [IQR]) time-to-intubation was fastest in the stylet ETT (25.0 s [20.9-32.2 s]) with the railroaded bougie being the slowest (43.2 s [36.5-56.2 s]). Seventy-nine per cent of participants stated that they would change their practice based on participating in this study. Participants increased their preference for the preloaded bougie from 30.6% to 69.4%.

Conclusion: The data show that tube passage with a stylet ETT or a preloaded bougie is superior in terms of higher first pass success, faster time-to-intubation and higher post-test preference. The naked ETT is clearly inferior to other methods. This research supports the recommendation to use a stylet ETT or bougie for every predicted difficult intubation.

Keywords: difficult airway; simulation; tracheal intubation.