Hypoxi & covid-19
Erika Schagatay, professor of zoophysiology, just published an article about how hypoxi ("preferable" state for us freedivers.!), and the covid-19 relates.
Erika writes that: "Humans adapt quickly to environments with limited oxygen supply. Trained freedivers can have an oxygen saturation of less than 50 percent when emerging from a dive and be perfectly clear. Many climbers at high altitude can work with an oxygen saturation of less than 70 percent."
She describes that it depends on the effective ability of the human body to adapt to oxygen deficiency. The adjustment can be done in a week, and perhaps many of the covid-19 patients who come to the emergency care to some extent are already adapted to hypoxia?
So what happens when people acclimate to hypoxia? A number of mechanisms in the body protect against oxygen deficiency, one is the so-called dive response (or mammalian dive response MDR), which redistributes the blood to the organs most sensitive to oxygen deficiency, the brain and the heart, while other parts get smaller. This saves oxygen, and the response is felt by the pulse going down. At the same time, vessels are shut off in, for example, the skin, hands and feet, and one can easily become cold (peripheral vasoconstriction)
Erika and her team's research have found that the reaction becomes stronger after only a week of diving training. If you hold your breath 5 times a day, the same thing happens: the diving response becomes more efficient and you have more oxygen left to the brain after a certain amount of breathing time. When adjusting to high altitude, similar changes occur, and one can actually predict a person's high altitude sensitivity by allowing the person to hold their breath at sea level
Full article here: https://lakartidningen.se/opinion/debatt/2020/05/manniskan-anpassar-sig-snabbt-till-hypoxi-koppling-till-covid-19/?fbclid=IwAR14gRasm_RPABXYgFNkKU3DBTGtWYgh7XQjs0deqLly-9Cn5Le2XtuhV5g