For some time my finger oximeter readings on 5litres of oxygen have fallen from 97 when starting at rest to 84 when I walk a short way in the house (for instance to the toilet). I have had no trouble for 5 years i have been on oxygen but recently I think my lungs have got worse. I try very hard to ensure i am breathing in through my nose where the oxygen prongs go!, but as I am a natural mouth breather I often forget. I am trying to breath in through my nose and take a step, breath in again and take another step etc.
Does anyone have a tip please on how to ensure I always breath in through my nose, or do you use a gadget that helps? Any tips would be welcome. Thank you.