Wiki Office visits after open access procedures at ASC

[psheppar]

Hello,
Our doctors are performimg colonoscopies and endoscopies in their ASC without seeing the patient in the office first. If the patient needs to be seen after the procedure in the office setting, what office code should be billed? New patient, established patient, or consult?
Also, does an ABN need to be signed for all providers involved at the ASC if needed? Doctor, facility, anesthesia, and lab? Or will one ABN cover all?

Thanks,