Changes to Oklahoma's health care power of attorney have taken effect this week, where now Oklahomans are unable to appoint someone to carry their health care wishes if they're not able to themselves. "This is a fundamental change to the way patients are able to express their wishes," said Jessica Zan, INTEGRIS Health's Manger for Advance Care Planning. "If we don't get the word out, I don't people left hanging with a document that doesn't have value, it's not fair to our community. "