General Surgery Billing Audit
Find the global-period, modifier and operative-note gaps that cost general surgeons revenue — and fix them before a payer audit does.
General surgery claims are denied less for missing information than for timing. Every surgical CPT code carries a global period of 0, 10 or 90 days, and any visit or procedure inside that window is presumed to be part of the package unless a modifier and the documentation prove otherwise. The decision-for-surgery visit needs modifier 57 for major procedures or 25 for minor ones, staged or more extensive follow-up procedures need 58, unplanned returns to the operating room for complications need 78, and unrelated problems need 79 or 24. Our audit samples operative reports and post-operative encounters together, so we can see where revenue was bundled away, where modifiers were appended without supporting documentation, and where the abdominal hernia code set introduced in 2023 (49591–49618, which now includes mesh placement) is still being billed the old way.
Audit red flags
- Post-operative visits inside a 90-day global billed as separate E/Ms without modifier 24 or 79 and an unrelated diagnosis.
- Modifier 59 or XS appended to force payment for procedures in the same anatomic area without documentation of a separate site or session.
- Abdominal hernia repairs still billed with deleted codes or with a separate mesh add-on.
- Assistant-surgeon claims (modifiers 80, 82 or AS) for procedures the payer lists as not eligible for an assistant.
Audit action plan
- 1. Operative Note Sampling — Review a random sample of operative reports against the billed CPT codes, modifiers and units to confirm every separately billable procedure was captured — and nothing unsupported was.
- 2. Global Period Collision Review — Match every E/M and procedure against open global periods to separate correctly bundled care from billable complications, staged procedures and unrelated problems.
- 3. Denial & Underpayment Trends — Group 90 days of remittances by CARC code (CO-97, CO-4, CO-236) and payer to find the edits driving denials and the contracts paying below schedule.
Codes reviewed
- 49591–49618 — Anterior abdominal hernia repair (by defect size, reducible vs. incarcerated, initial vs. recurrent)
- 47562 / 47563 — Laparoscopic cholecystectomy / with cholangiography
- 11042–11047 — Debridement by depth (subcutaneous tissue, muscle/fascia, bone)
- E/M + 57 / 25 — Decision-for-surgery and same-day evaluation visits
Frequently asked questions
Can a general surgeon bill an E/M visit on the day of surgery?
Yes, when the visit is the decision for surgery. Use modifier 57 for the decision visit on the day before or the day of a procedure with a 90-day global period, and modifier 25 for a significant, separately identifiable evaluation on the day of a minor procedure (0 or 10-day global). The note has to show the evaluation went beyond the usual pre-procedure assessment.
What changed with abdominal hernia repair coding?
Starting in 2023, CPT replaced the ventral, umbilical, spigelian and incisional hernia repair codes with 49591–49618, selected by total defect size, whether the hernia is reducible or incarcerated/strangulated, and whether the repair is initial or recurrent. Mesh implantation is now included and is no longer reported separately.
When should modifier 78 be used instead of 79?
Modifier 78 is for an unplanned return to the operating room for a related complication during the global period, and it does not start a new global period. Modifier 79 is for an unrelated procedure during the global period, and it does start a new one.