I just started using e-cigs recently and it's been great. I am trying to convince my mother to use them. She tried one of mine and she liked it. BUT, she's been a HEAVY smoker for over 50 years and has emphysema. She also had head and neck cancer (she's 5 years out of treatment and okay) of undetermined origin that they are pretty sure was caused by her smoking. Her emphysema has gotten so bad they may be putting her on oxygen. I know she should just quit altogether, but I honestly don't think she can. So, I thought e-cigarettes would at least be a better alternative. However, I don't want to get her all excited about them if it turns out she can't use them safely if she's on oxygen at home. Does anyone have any experience with this? Thanks for any help and advice you can offer.