Abstract:
INTRODUCTION : SARS-CoV-2 has resulted in increased worldwide demand for personal protective equipment (PPE).
With pressure from ongoing epidemic and endemic episodes, we assessed an adapted snorkel mask that provides
full-face protection for healthcare workers (HCWs), particularly during aerosol-generating procedures. These
masks have a custom-made adaptor which allows the fitment of standard medical respiratory filters. The aim of
this study was to evaluate the fit, seal and clinical usability of these masks.
METHODS : This multicentre, non-blinded in-situ simulation study recruited fifty-two HCWs to don and doff the
adapted snorkel mask. Negative pressure seal checks and a qualitative fit test were performed. The HCWs
completed intubation and extubation of a manikin in a university skills training laboratory, followed by a webbased
questionnaire on the clinical usability of the masks.
RESULTS : Whilst fit and usability data were generally satisfactory, two of the 52 participants (3.8%) felt that the
mask did not span the correct distance from the nose to the chin, and 3 of 34 participants (8.8%) who underwent
qualitative testing with a Bitrex test failed. The majority of users reported no fogging, humidity or irritation. It
was reportedly easy to speak while wearing the mask, although some participants perceived that they were not
always understood. Twenty-one participants (40%) experienced a subjective physiological effect from wearing
the mask; most commonly a sensation of shortness of breath.
DISCUSSION : A fit-tested modified full-face snorkel mask may offer benefit as a substitute for N95 respirators and
face shields. It is, however, important to properly select the correct mask based on size, fit testing, quality of the
three-dimensional (3D) printed parts and respiratory filter to be used. Additionally, HCWs should be trained in
the use of the mask, and each mask should be used by a single HCW and not shared.
Description:
APPENDIX A. SUPPLEMENTARY DATA. APPENDIX B. Fig. B1: A. The SEAC Libera full face snorkel mask, and B. The Mares Sea Vu Care full face snorkel masks, used in this study. Fig. B2: Adapter for A: SEAC Libera Med+ mask and B: Mares Sea Vu Care. Fig. B3: Clear-Guard 3 Breathing Filter used in this study. APPENDIX C. Intubation and extubation checklists. APPENDIX D. Comparison of the different snorkel masks. APPENDIX E. Google form to determine clinical usability of the full-face snorkel mask.
