It is important to know how effective the exchange of gases is taking place in the in lungs. Not only in respect of o2 into the bloodstream but also of co2 out of the bloodstream into the lungs. A build up of co2 will cause the blood to become more acidichttps://twitter.com/DanielleFong/status/1278700215692918784 …
from what I understand exhalation of CO2 is actually more important, this is why rebreathers are effective and relatively low CO2 levels of like 2000 ppm (still 1/100th oxygen levels) cause major cognition problems and grogginess and so on.
