FWIW the last person I know who had that exact problem was pretty much dragging on and not really recovering from the dope. I took a bigaxx bottle of industrial oxy and a regulator with face mask and set it up for her.(2 cc flow) I suggested she take 1/2 hour early and late in the day. Within two weeks she was back doing the Monday crossword by herself. Now she won’t let me have my bottle back. Just sayin’.
I know that breathing is vital for everything and helps the brain and mind as well. I should do breathing exercises. My thing was 3 years ago.