Was in hospital over Christmas and not allowed home until 2 concentrators had been installed in the house. The reason was that I had v low arterial blood gas levels and mild sleep apnoea. I was told I would need the oxygen for "life". (Am 67) Have seen the consultant twice more since then and despite the oxygen I still have a v low arterial level &, apparently, I retain carbon dioxide. They test the arterial blood each time I go & make their decision based on that. Each time I have asked the consultant whether I have COPD & he always says "probably". This week he added "but we still don't know why you are so hypoxic". When I said that I don't have any symptoms he responded by saying that COPD can be "asymptomatic". I don't have a further appointment for 6 months when he said they would do some more spirometry. I have no idea what my FEV is - I've realized by coming on the forum how important that is in diagnosing COPD. I feel a lot better in myself since I've been on the oxygen - am no longer constantly exhausted. To be honest, I'm a bit baffled by it all.