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Mask protects against SARS-CoV-2, the coronavirus that causes Covid-19. Vaccine protects against severity of Covid-19. And, oxygen gives extra hours and days to patients for medicines to alleviate symptoms. The oxygen that a Covid-19 patient requires is medical oxygen.
Medical oxygen is produced in specialised manufacturing units as industrial oxygen and purified over 93 per cent for the use of patients suffering from oxygen starvation. In the cases of Covid-19, severely ill patients need oxygen support as they fail to utilise environmental oxygen in their respiration.
Oxygen need of Covid-19 patients vary depending on the severity of their illness. On an average, less than 10 per cent Covid-19 patients need oxygen support. Fewer number of Covid-19 patients require usage of high flow nasal cannula (HFNC).
WHY COVID-19 PATIENT NEED OXYGEN SUPPLY?
An average adult person inhales and exhales about seven to eight litres of air while resting in a minute. This is about 11,000 litres of air per day. Inhaled air contains 21 per cent oxygen (environmental composition) and exhaled air contains about 15 per cent oxygen. The difference is absorbed by the lungs. If there is a shortage, it needs to be supplemented.

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