Construct and submit an X12 278 prior authorization request and poll for the 278 response or pend notification

Verified steps

1. Build the 278 request (005010X217): ISA/GS envelope, ST*278 with BHT*0007 (request), Loop 2000A utilization management organization loop, Loop 2000B requester loop, Loop 2000C subscriber loop with member demographics and insurance info, Loop 2000D patient loop if different from subscriber
2. In Loop 2000E (service loop) populate UM segment: UM01 request category code (HS=health services review, SC=specialty care review), UM02 certification type (1=initial, 2=renewal), UM09 service type code; include HCR segment for health care review information
3. Add SV1 (professional) or SV2 (institutional) service line segments with procedure codes, diagnosis pointers linking to HI segments, and requested units; attach DTP segments for anticipated service dates
4. Submit to the payer or clearinghouse endpoint; an immediate 278 response with AAA=approved or a HCR pend code may return synchronously, or the payer may return a pending acknowledgment and respond asynchronously
5. If response HCR01 is 'A1' (approved) extract the authorization number from REF*BB and store it for claim submission; if 'A3' (not medically necessary) or 'A4' (denied) capture the reason codes from HCR and plan appeal
6. For pended responses poll the status endpoint or await an unsolicited 278 response; match on the TRN trace number from the original request