How do you decide that a loved one is no longer capable of making medical decisions

I think I have shared that my Mom is currently having health problems. In addition she has had mild dementia, mostly short term memory problems, for some time. It has been difficult to determine where she no longer could function although there were many spaces where she was just fine.

Increasingly it became clear to me that there was a critical link between short term memory problems and ability to make decisions. If you can't remember the information you received although you discussed it clearly and rationally at the time it was give, how can you make a good decision? No access to critical information means poor decisions.

This all came to a head this week when she needed to agree to a medical procedure and couldn't do that. Fortunately we had medical power of attorney and the facility agreed that it was time to activate it. So now my brother and I are the decision makers. This is now causing her some distress unfortunately. The good news is we got two unnecessary medications removed from her daily regime and hopefully as they work their way out of her system we will see some improvement in her cognitive capability.

I am not bringing this up because of my Mom's situation but because it is so hard to deal with slowly progressing dementia which may become significantly worse under stress or during an illness. How do we talk to our potential caregivers about when to take action? Do we all have medical powers of attorney in place? Why are healthcare providers so slow to address the implications of dementia in the oldest of patients?

I don't know the answers to these questions, but I think we should all be thinking and talking about how to ensure good care for our loved ones and ourselves.