Prognosis of Peripheral Vascular Disease (aka Peripheral Artery Disease)?

My mother is 83 y/o; nursing home resident; hx of ruptured brain aneurysm 28 years ago; bed-bound - needs Hoyer Lift to transport her from bed to chair; non-ambulatory -- unable to bend her legs. Chronic pain in legs and feet; poor circulation; Doppler Study revealed stenosis - occlusion in right leg and diminished pulses in left leg/foot. Dementia with aphasia; difficult to communicate her needs; but responds to pain; recognizes caregivers and myself and other family members; able to feed self with assistance; vital signs are good. In all likelihood, my mother will pass from some type of cardiovascular or cerebrovascular event. She is unable to "exercise" or do much more than lay in bed or sit (uncomfortably) in a wheel chair. Poor quality of life. Wish I had a magic ball to predict how much longer she will live like this...anyone have similar experience? Should we shift to palliative care or Hospice?