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Paediatric headbox as aerosol and droplet barrier
Monica Sahih1, André Schultz2, Andrew Wilson3
1Department of General Paediatrics, Perth Children's Hospital, Perth, Western Australia, Australia monica.sahih@health.wa.gov.au.
Background:
High-flow nasal oxygen (HFNO) is frequently used in hospitals, producing droplets and aerosols that could transmit SARS-CoV-2.
Aim:
To determine if a headbox could reduce droplet and aerosol transmission from patients requiring HFNO.
Methods:
The size and dispersion of propylene glycol (model for patient-derived infectious particles) was measured using a spectrometer and an infant mannequin receiving 10-50 L/min of HFNO using (1) no headbox, (2) open headbox, (3) headbox-blanket or (4) headbox with a high-efficiency particulate (HEP) filter covering the neck opening.
Results:
All headbox set-ups reduced the dispersal of droplets and aerosols compared with no headbox. The headbox-blanket system increased aerosol dispersal compared with the open headbox. The fraction of aerosols retained in the headbox for HFNO of 10 and 50 L/min was, respectively, as follows: (1) open headbox: 82.4% and 42.2%; (2) headbox-blanket: 56.8% and 39.5%; (3) headbox-HEP filter: 99.9% and 99.9%.
Conclusion:
A HEP-filter modified headbox may serve as an effective droplet and aerosol barrier adjunct for the protection of staff caring for children receiving HFNO.
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