Sils, very sorry to hear that. Of course i do not know how bad her case is, but like Amethyst, my father-in-law lives with Emphazema, and he has had it for at least 10 years, and is not on oxygen yet. He has good days and bad days, but mostly good, and they have him on meds and inhalers that keep in in control.
Try not to worry too much, thought i KNOW that is so much easier for me to say then for you to do - but wait and see what they say and suggest in means of treatment and see how she gets on, and hopefully there will be some relief.
One thing I can say is just be very careful about her catching colds that can turn more easily into chest infections. Those are the time my FIL is at his worst. So keep people wiht colds away!
I know how scary it is. But hopefully, she has many years still that will be quite comfortable and happy.
Hang in there hon.....<<hugs>>