Intubator Performance and Contamination with the Use of Barrier Enclosure Devices: Results from a Simulated COVID-19...

Medical institutions are using barrier enclosure devices during intubation procedures and other aerosol-generating medical procedures without evidence of their effectiveness or usability, potentially compromising patient care, and provider safety. Our objective was to determine the degree of protection offered by these devices and explore other usability factors for two popular barrier systems.

A simulated trial comparing an intubation box, a frame and plastic tarp system, and unprotected intubation was performed in an academic emergency department. Ten emergency physicians were recruited to participate. Our primary outcome was the degree of contamination from secretions measured by average surface area exposed to phosphorescent material. Secondary outcomes included: laryngoscopy time and time to barrier application, unsuccessful intubation attempts, and usability ratings for each system. Descriptive statistics were reported for all variables of interest and a linear mixed model was used to analyze contamination and laryngoscopy time. Usability was captured through electronic questionnaires using a five-point Likert scale.

Contamination was more prevalent with the box, compared to the frame and tarp, and no device, however, this did not achieve statistical significance (13.2% versus 8.1% versus 12.2%, P = 0.17). A barrier system delayed intubation when compared to using no system (no system = 24.4 s [95% CI 17.3-27.5], frame = 54.4 s [95% CI 13.8-95.0], box = 33.8 s [95% CI 21.4-46.1], P = 0.02). In assessing usability, 30% of users preferred the use of a box barrier, 40% of users preferred the frame, and 30% would not use either in future intubation.

Compared to no barrier protection, an intubation box enclosure offers limited additional protection. A frame and tarp system reduces exposure at the expense of visibility and operator comfort. Finally, barrier systems do not appear to have a clinically significant impact on airway management.