Can you provide information about when it is appropriate to use modifier 63?
According to the Centers for Medicare & Medicaid Services (CMS), you will now be able to append modifier 63 (procedure performed on infants less than 4 kgs.) to select Medicine/Cardiovascular (90000-series) codes to describe increased complexity of procedures performed on patients of less than 4 kg (approx. 8.8 lb.). Note that CPT does not allow modifier 63 for procedures involving congenital anomalies, or those valued to reflect heightened complexity associated with prematurity. See the 2019 CPT manual appendix F for more information about modifier 63 exempt codes.