What should we expect after a traumatic surgery on an Alzheimer's patient?

I care for my grandma who had sudden onset Alzheimer's. She is wheel chair bound after a fall caused a broken femur and resulting rod and plate in her leg. Fear kept her from rehabilitating and walking again. Only a year ago my grandpa passed, and she rapidly fell in to Alzheimer's. In that year she no longer knows us, how to eat, how do many basic small tasks. This past week she fell in the middle of the night, from her bed. She's recently begun night waking. She was with my mom at the time and 911 was called. At the hospital they found a large brain bleed and did emergency life saving surgery. She was ok before surgery, as ok as she had been. She was asking not tio go alone and told my mom I love you. Now in ICU she is a completely other person. She is flailing and unable to be understood, she makes eye contact only very very rarely and is frantic. It's been 5 days since surgery with little to no improvement. She's my heart and I'd trade places with get in a heart beat. My question is this...it's there any hope she won't be like this for the rest of her life? Is it possible her life was saved only to live the torment she's in now? Anyone with experience? No one is telling us what to expect.