Human and other living beings breath air which contain 21% oxygen and 78% nitrogen. We are well adapted to such air mixture. It is well established that oxygen in higher concentration especially above 40% is toxic and starts causing oxidative damage to alveoli, respiratory tract, surfactants.
Anti-oxidant mechanisms in lung try to protect from this oxidative damage but soon they start failing after few hours to days. This oxidative damage causes lung injury by disrupting cellular integrity of alveolar and other cells leading to inflammation and accumulation of fluids lungs and impairment of gas exchange, alteration in pulmonary dynamics by damage to surfactant and contributing to complications and deaths. In covid respiratory system is already inflamed and in such case high dose oxygen therapy further increases inflammation by oxidation further leading to hypoxia which causes treating…
