Part B Insider (Multispecialty) Coding Alert

If a patient comes back after surgery with a problem related to the diagnosis that caused surgery but unrelated to the surgery itself, how should you bill for it?

These are the kinds of problems that many coders struggle with daily, says Marcella Bucknam, CPC, CCS-P, CPC-H, HIM coordinator at Clarkson College in Omaha. Understanding the circumstances under which you should use modifiers -24, -25 or -57 means understanding how global periods work.

For example, many coders don't understand that any surgery with a 90-day global period will also have a one-day period before surgery covering presurgery services. But this isn't true for procedures with no global period or a 10-day global period, Bucknam points out.

Thus, you'd use modifier -57 for E/M services the day before an appendectomy or breast biopsy, but not for a more minor service, Bucknam says.

If a service has a 10-day global period or none at all, you may well be performing that service on the same day the patient first comes in for an E/M service. In such cases, you'd use modifier -25. For example, if a patient needs a simple laceration repair, which has a 10-day global period, you should append modifier -25 to the E/M code, or it will be bundled.

Of the three modifiers, "-24 is probably the one people understand the least," Bucknam says.

Most people understand that if a patient has an appendectomy and then breaks a leg a few weeks later, the broken leg is unrelated to the appendectomy. But far fewer understand when they should use modifier -24 for services that are directly related to the diagnosis that caused the surgery.

The global period after surgery covers such postoperative concerns as managing minor infections or dealing with stitches. But if you've done a bypass surgery for a diabetic patient with peripheral vascular manifestation, that patient will still need to see the surgeon about anticoagulant medication such as heparin. Both services relate to peripheral vascularitis, but they're unrelated, Bucknam says.

For E/M services performed during the global period following a procedure, Bucknam recommends using modifier -24. For another procedure that's unrelated to the earlier surgery, she uses modifier -79, for example if the diabetic with peripheral vascularitis requires an arteriogram or an injection of sclerosing material.

Physicians frequently lose money by failing to bill for services provided during the global period that are unrelated to a surgery but related to the same diagnosis, Bucknam says.