Mom just diagnosed with depression and anxiety. Is it too late to get power of attorney?

Also tested for dementia in intensive care, but hospital had her sign documents to admit her to geriatrics behavior ward because she repeatedly said for us not to sign for her because she didn't want us to be responsible for her hospital bill.
(at the time she was being treated for overdose. )The hospital wanted us to sign and guess what in small print it said we would be responsible for bill. The hospital is out to protect itself because they waited until last minute to show us the documents even though we waited for 4 days for them to admit her to behavior unit. Yes this really happened and I could not believe it either. They seem to count on desperate family members who want to get treatment for their loved ones. And even if they say no that is not what it means they want to make sure someone will pay the bill. Yes she has insurance and Medicare. Really make you wonder how to trust medical profession.