Background Concerns over high transmission risk of SARS-CoV-2 have led to innovation and usage of an aerosol box to protect healthcare workers during airway intubation in patients with COVID-19. Its efficacy as a barrier protection in addition to the use of a standard personal protective equipment (PPE) is not fully known. We performed a simulated study to investigate the relationship between aerosol box usage during intubation and contaminations on healthcare workers pre-doffing and post-doffing of PPE.
Methods This was a randomised cross-over study conducted between 9 April to 5 May 2020 in the ED of University Malaya Medical Centre. Postgraduate Emergency Medicine trainees performed video laryngoscope-assisted intubation on an airway manikin with and without an aerosol box in a random order. Contamination was simulated by nebulised Glo Germ. Primary outcome was number of contaminated front and back body regions pre-doffing and post-doffing of PPE of the intubator and assistant. Secondary outcomes were intubation time, Cormack-Lehane score, number of intubation attempts and participants’ feedback.
Results Thirty-six trainees completed the study interventions. The number of contaminated front and back body regions pre-doffing of PPE was significantly higher without the aerosol box (all p values<0.001). However, there was no significant difference in the number of contaminations post-doffing of PPE between using and not using the aerosol box, with a median contamination of zero. Intubation time was longer with the aerosol box (42.5 s vs 35.5 s, p<0.001). Cormack-Lehane scores were similar with and without the aerosol box. First-pass intubation success rate was 94.4% and 100% with and without the aerosol box, respectively. More participants reported reduced mobility and visibility when intubating with the aerosol box.
Conclusions An aerosol box may significantly reduce exposure to contaminations but with increased intubation time and reduced operator’s mobility and visibility. Furthermore, the difference in degree of contamination between using and not using an aerosol box could be offset by proper doffing of PPE.
- infectious diseases
- emergency department
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Handling editor Katie Walker
Contributors MNA provided the conception and design of the study, analysis, validation and interpretation of data, drafted the manuscript, revised it critically for important intellectual content, and provided final approval of the version to be submitted. AB provided the design of the study and data collection instruments, analysis, validation and interpretation of data, drafted the manuscript and revised it critically for important intellectual content, and provided final approval of the version to be submitted. KP and AZAZ provided the design of the study, coordinated and supervised the acquisition of data, drafted the manuscript and revised it critically for important intellectual content, and provided final approval of the version to be submitted. MZAMN, MAAA, MHMY, AZ, JYOC, AK, BTA and AI supplied the acquisition of data, revised the drafted manuscript critically for important intellectual content, and provided final approval of the version to be submitted. AZ and AK coordinated the blinding of investigators and revised the drafted the manuscript and for important intellectual content. KSC revised the drafted manuscript critically for important intellectual content.
Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.
Competing interests None declared.
Patient consent for publication Not required.
Ethics approval This study was granted ethics approval from the University of Malaya Medical Research Ethics Committee (MREC ID number: 202041-8412). Enrolment of participants was voluntary, and each recruited participant signed an informed consent form.
Provenance and peer review Not commissioned; externally peer reviewed.
Data availability statement Data are available upon reasonable request. The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.
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