Gangrene

My mother is 93 years old and had gangrene on her heel. She also has severe dementia and arteriosclerosis. We were informed that amputation was needed to prevent it from infection and spreading. She has asked that no surgery or Antibiotics be done. She has lived a long life and is ready to "go home". I'm trying to find out what, under these circumstances, we can expect. Bottom line is I am looking for what kind of timeline we can expect on the progression. Some are say it could be months; others are saying once infection hits, it is fast. There seems to be a lot of unanswered questions and even the doctors are giving us any idea as to how this will play out. Any assistance would be appreciated. Tweet