Can my 86 year old Mother claim a hospital bed (craftmatic) and a chair lift she purchased when she moved in with my sister. She has a prescription from her doctor?

Yes, as long as your mother has prescriptions requiring the bed and chair, she is able to claim them as medical expenses.  If you look at the following link, you can scroll and see this for both the chair and bed.

http://www.cra-arc.gc.ca/E/pub/tg/rc4065/rc4065-e.html#prdctsdvcssppls