HI welcome to HCM I have gone thru your query , I can understand your concern about your mom s health . But dear ,you have not mentioned ,for what she hadto under go surgery ? And her age ? Low level of oxygen can be due the side effects of medication ,she is getting Any way , I, as a Naturopath ,Homeopath & magneto therapist ,will suggest you ,to understand the importance of Natural ways of life to be followed , with all the tests , surgery and medication . Both are equaly essential tools for a successfu treatment . Normally we don t breath to the fullest of our lungs . That is why our fore fathers intoduced yoga and pranayam as given in Vedas to help mankind to stay healthy So ,as she has undergone surgery ,will go for apnea test next week . She won t be able to follow any exercise / yoga . Meanwhile ,she can go for pranayam --deep breathing - To start with - breath deeply -but gently , Inhale --hold -- Exhale -- hold . Repeat for 5-15 times Do it several times a day to detoxify and increase oxygen in your body for total health .She will feel the difference within a day . Breath is life so we can expect to feel more alive, vibrant and healthy if we bring our awareness to our breath and retrain the way we breathe. When we breathe perfectly we can live more perfectly in health because our breath is the most important source of energy. Hippocrates said, “Air is a pasture of life and a greatest ruler of all.” I suppose he knew what ancient oriental philosophers knew—that in the air is “an ocean of energy” ready to be tapped directly into. And taught natural breathing. We are able to improve the functioning and efficiency of our heart, lungs, and other internal organs and systems. We are able to help balance our emotions. With all this, proper balanced diet containing all essential nutrients & anti oxidants , proper rest avoidance of fried ,fast foods , alcohol , tention ,worry anger and constipation ,We are assured of happy ,healthy disease free life . Hope this helps you solve your query Take care All the best Don hesitate to come back if any further query. .