We have received questions from trading partners wishing to use the ICD-9-PCS procedure codes to report hospital outpatient services at the claim level in the situational Principal Procedure HI segment.  This will cause such claims to be rejected.

ICD-9-PCS procedure codes were named under HIPAA as the mandatory standard code set for inpatient hospital procedures and home infusion therapy that was initiated from hospital inpatient surgery, and for no other purposes.  The ICD-9-PCS procedure codes were not named as a HIPAA standard for procedures in other settings such as hospital outpatient services or other types of ambulatory services.  Hospitals may capture the ICD-9-PCS procedure codes for internally tracking or monitoring hospital outpatient services; but when conducting the HIPAA standard transactions, hospitals must use HCPCS codes at the service line level to report outpatient services.  The HCPCS code set includes both the numeric CPT codes and the alphanumeric HCPCS.