Medical POA won’t give updates on our mother's care. Any advice?

I was my Moms POA and as such I knew I was not suppose to devulge anything about her finances. Same with Medical.

What I did was act as I thought Mom would. My brothers trusted my decisions so didn't ask so I didn't tell. I was told if I had any out of pocket tell them. Since the house was being sold, I said we could settle that up at closing. Her health...Mom never kept secrets. So I was sure she would be OK with me keeping them in the loop. They asked, I told.

I really feel people get carried away with POAs. You are representing the person who assigned you. You should be thinking they way they would have. If its in writing then you go by that. This keeping a child away from a parent for no other reason than power is awful.

The medical POA doesn't HAVE to give any information. When an MD discusses with a POA the legal condition and the legal options for a patient it has the same privacy protections as discussing it with the patient him or herself.
Is there a problem between siblings? Is one sibling in charge while others feel kept in the dark. Or is the POA not even a sibling, but rather a spouse or friend? Is the POA protecting privacy rights of Mother?
Do know that the POA is the Lion or Lioness at the Gate. They have the power. Therefore, if you wish to be updated, the best thing to do is ask (or beg) to be updated as the POA feels your Mom would wish you to be, with no more nor less information than the POA thinks your Mom would wish you to have. Offer support and help to the POA. If visits are a concern offer to visit with the POA present. Tell the POA that he or she is in charge and that you trust his or her decisions (because truth told you are going to HAVE to trust those decisions; your Mom made the medical POA in charge).
More bees are caught with honey and flowers. If that doesn't work you won't be getting any bees at all.
You should, if you have tried all of that, consider asking to see the Social Worker. Occ. they will attempt to mediate by contacting the POA and going over what they are comfortable with sharing and what they are not. But if you are at war with the POA they are unlikely to intervene.
Wishing you good luck.

Assuming you mean your mother's medical POA (power of attorney) will not give you updates on her care........why not go visit her yourself??

From your profile:

I am caring for my mother Regina, who is 88 years old, living in a nursing home with alzheimer's / dementia and mobility problems.