In lieu of scrapping the entire mess, there should be a required line on the HIPAA forms designating someone who the medical provider can contact. Not very many sick people are in the best position to understand everything that doctors tell them, simply because they are sick. Everyone needs an advocate - an extra pair of eyes and ears and thinking processes.
There is a way around this. It is called a "Power of Attorney." My in-laws both had them naming my wife as the one to make health care decisions. She used the POA as it should be done, and discussed all treatment plan with their physicians. Even though they had dementia and other diseases that altered the way they would make decisions they both received excellent medical care directed by someone who loved them.
After seeing the treatment my in-laws received and the treatment others without a POA received, we have a medical POA in place for each of us including children when they reach 18.