Modifier -78 Versus -79

October 1, 2007

Here is some expert medical coding guidance on when to use modifier -78 versus modifier -79 for a second procedure.

Question: The doctor performs a surgery, and then, because of complications, performs a second operation eight weeks later. The second procedure is done during the first procedure’s global period. Do we bill the second procedure using modifier -78 or -79? This was not a staged procedure.

Answer: According to Sheri Bernard of the American Association of Professional Coders (AAPC):

When you use modifier -78, it streamlines reimbursement if you show medical necessity for the return to the OR. The 996 family of ICD-9-CM codes are used to describe complications specific or peculiar to specified procedures. It is unclear in this case if the failure to maturate was a flow issue versus a stricture. ICD-9-CM code 996.2 designates a mechanical problem with the AV fistula such as a stricture or thrombus. ICD-9-CM code 996.73 relates an ‘other complication’ of a vascular dialysis catheter. Recognize also that some third-party payers, such as CMS, will reimburse only the intraoperative portion of the procedure and will not restart the global days.

Modifier -78 is the best selection if there is a complication in this case. The official CPT description for modifier -78 says, “When this subsequent procedure is related to the first, and requires the use of the operating room, it may be reported by adding modifier -78.” The two procedures are clearly related. You would not report modifier -58 because this was not planned as a staged procedure. Modifier -79 applies only to “unrelated” services, for example, if the patient returns to the OR for a cholecystectomy following an AV fistula procedure.