You have No obligation to see a patient that clearly owes you legitamate funds for previous care. OK you have to make sure there is no serious life or limb pathology that will occur within the next 12-24 hours ( not a law, just simple ethics ).
If you see this patient and incur further financial loss, you have no one to blame but yourself.
Can anyone show me a successful legal proceding that was brought against a healthcare provider for not seeing a patient bc lack of payment? I doubt it.
Maybe your landlord, the phone company, the power company, your staff, and your mal-practice carrier will give you a discount b/c some of your patients owe you money. Sure they will.
Come on people!

Nate