rubylady -
this is a difficult situation for you. I think the only thing you can do is be guided by the medical team and discuss the situation with them, at length if necessary.
I don't know what LPA is but I think that you are your dad's main carer so it's very hard for you.
Having been very close to cancer and dementia in the last few years and having been the main carer on two occasions, I learnt to ask for support where ever I could find it.
This situation is potentially exhausting for you, so ask lots of questions, see what help is there and try to rest (as you are doing) when ever you can - lots of hugs, stay strong.