Post operative pain blocks are one thing that come to mind that would require the 59 modifier.
Below is a Q and A from the AMA in determining which anesthesia code to pick when there are multiple procedures and usually CCI does not effect this determination, typically reviewing the most comprehensive procedure and the associated base units for the relevant anesthesia codes
Question
When multiple procedures are performed, how is anesthesia administration reported?
Answer
Generally, a single code is reported for anesthesia administration, whether the operating physician performs one or multiple procedures. When multiple procedures are performed during a single anesthetic administration, usually only the procedure code for the most complex service and the total time for all procedures are reported. Anesthesia add-on codes are an exception. Codes 01953, 01968, and 01969 describe anesthesia add-on procedures, which are reported in addition to the primary anesthesia codes.