What is a reason to end up multiple times a week in ER?

This happened with a friend's mother during her last year of life. She had dementia, cardiac problems, infections, breathing problems, a whole litany of symptoms of slow death. But she didn't have any one clearly terminal condition (like late stage cancer) that would justify a switch to hospice, so she lived in an assisted nursing facility and also had to go to the ER more than 70 times in that last year. It was horrifying for everyone and the costs were astronomical. The state is now trying to seize her daughter's house to partially offset the accumulated expenses.