Can we bill a patient when Medicare Provider is non-par?

Hopefully someone can give insight. If a provider sees a patient as INPT, patient has Medicare only and the provider is non-participating at that time of service, Medicare states balance is patient responsibility on eob. However, the patient states that balance should be written off due to not requesting to be seen by this provider. Patient was sick and cannot make decisions of which provider to see. I don't know if the hospital is responsible of letting providers know that the patient to be seen, the service will be outofnetwork. Is this a downfall on the hospital or provider? Is the provider responsible of knowing that the patient has Medicare and he claim will be processed out of network? What is the true process for this situation? Sounds like there are ethical issues vs payor processing issues.

Any input is appreciated.

it depends

As a non-participating physician, you probably have an obligation in the hospital to inform patients of their financial liability before initiating services and letting them express an opnion. If you are a specialist and a primary care doc consults you, it is easy to tell te PCP to call another specialist if the patient refuses your payment terms. If you are the primary care doc on call for the ED and the patient is assigned to you as they have no PCP, you have the right to bill the patient if you provided a service.