Father is 86 with mid to late stage dementia. Very sweet, like a child, during day. At night he wakes up 3 times, very aggressive, tries to get out of his hospital bed (bars are up), but will first take his penis out of diaper and wets bed and floor. He does take a sleep aid and we do stop water intake at 6pm.
Other than medications, which I must assume you have discussed with doctor and tried without much success, there is little to be done about this behavior, and living with it 24/7 simply isn't sustainable. I wish I had a magic wand and a better answer. Just don't have either of those things.
If this hospital bed is part of hospice, you should have Ativan and seroquel to sedate him as needed.