Feeding tubes and elderly?

my mother is in her seventies and is mentally not there completely...for ears she been having swallowing problem....food end up in her lungs....they just did a swallowing test and it was determine that a feeding tube was required...she refuses to let them do it and the home said if that is what they want they are not placing themselves in a liability problem by feeding her. So mom has to feed herself and that is hard for her. Add to this she has very very weak lungs from smoking most of her life...what can I expect and could we get the courts to give guardianship to me so I can get the feeding tube done?