early detection of silent hypoxia in COVID-19 patients using smartphones21 Sep 2020 12:01
" COVID-19 pneumonia causes oxygen deprivation that is difficult to detect since the patients do not experience any noticeable breathing difficulties, hence causing a condition which he terms as “silent” hypoxia. By the time COVID-19 patients realize they are short of breath, their conditions have already significantly deteriorated into moderate-to-severe levels of pneumonia. Analysis of COVID-19 pneumonia patients revealed that the virus initially attacks the lungs in a different way. The air sacs in COVID-19 patients’ lungs do not fill with fluid or pus as in normal pneumonia infections but rather the virus only causes the air sacs to collapse, thereby reducing the oxygen levels that lead to hypoxia in these patients but still maintains the lungs’ normal ability to expel carbon dioxide. "
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7305055/