Not so long
If you think about it, hemodialysis
sessions, which last 3 to 4 hours 3 times a week, do not really take that much time.
By this i mean that the dialysis machine is able to clean and filter your blood in about a half a days time in a week. This replaces your kidneys which function 24/7 all week. If your kidneys are not functioning, the time on dialysis is well spent.