Simulations of aerosol dispersion due to COVID-19 patients in ICU rooms
The COVID-19 pandemic has generated many concerns about cross-contamination risks, particularly in hospital settings and Intensive Care Units (ICU). Virus-laden aerosols produced by infected patients can propagate throughout ventilated rooms and put medical personnel entering them at risk.
Experimental results found with a schlieren optical method have shown that the air flows generated by a cough and normal breathing were modified by the oxygenation technique used, especially when using High Flow Nasal Cannulae, increasing the shedding of potentially infectious airborne particles.
This study also uses Computational Fluid Dynamics to simulate the air flows as well as the movement of particles produced by a patient’s cough within an ICU room. The effects of different mitigation scenarii on the amount of aerosols potentially containing SARS-CoV-2 that are extracted through the ventilation system are investigated. Numerical results indicate that adequate bed orientation and additional air treatment unit positioning can increase by 40% the number of particles extracted and decrease by 25% the amount of particles deposited on surfaces 45s after shedding.
Full reference of the article: Crawford C, Vanoli E, Decorde B, Lancelot M, Duprat C, Josserand C, Jilesen J, Bouadma L, Timsit J-F (2021) Modeling of aerosol transmission of airborne pathogens in ICU rooms of COVID‑19 patients with acute respiratory failure. Nature Portfolio; Scientific Report 11:11778