CurrentPremera BluecrossPolicy CP.PP.147.v3.0

Modifier 79 Unrelated Procedure/Service by Same Provider during Postoperative Period

Defines when Premera Blue Cross recognizes and allows use of CPT modifier 79 on professional claims (CMS-1500 or 837P) to indicate a completely unrelated surgical procedure performed by the same provider during another procedure's postoperative period; applies to Health Plan of Washington, LifeWise Assurance Company, and Premera Blue Cross HMO lines of business and products.

Policy Summary

PayerPremera Bluecross

PolicyModifier 79 Unrelated Procedure/Service by Same Provider during Postoperative Period

Policy CodePolicy CP.PP.147.v3.0

Change TypeClarification and documentation requirement

Effective Date

Next Review Date

Key ActionAppend modifier 79 to a surgical service on CMS-1500 or 837P only when the subsequent surgical procedure is completely unrelated to the original surgery and documented as such.

SourceLink

POLICY UPDATE CHANGES

Clarified that modifier 79 is appropriate for procedures following an initial procedure with 10-day or 90-day global periods and not appropriate following procedures with 0-day global period.

Stated that documentation in the patient's medical record must clearly indicate the subsequent procedure is unrelated to the prior surgery.

Removed statement that modifier 79 should not be applied to Ambulatory Surgery Center (ASC) facility services.

Clarified that modifiers 58, 78 and 79 do not bypass usual fee adjustments (multiple procedure, bilateral, assistant surgeon, etc.) and that these modifiers are mutually exclusive.

CMS-1500 / 837PClaim forms this policy pertains to

10-day or 90-dayAppropriate global periods

0-dayNot appropriate for

Mutually exclusiveModifiers mutually exclusive

When Modifier 79 Is Recognized

Coding Guidance and Applicable Global Periods

Modifiers guidancemixed

Modifier 79	Unrelated Procedure/Service by Same Physician During Postoperative Period
Modifier 78	Unplanned return to the Operating Room for a Related Procedure by the same Physician during the Postoperative Period
Modifier 58	Staged or Related Procedure or Service by Same Physician During Postoperative Period

Applicable global periods — Modifier 79

Applicable global periodsModifier 79 is appropriate following procedures with 10-day or 90-day global periods as defined by CMS; it is not appropriate following an initial procedure with a 0-day global period.

New postoperative periodWhen Modifier 79 is allowed, the unrelated procedure begins a new postoperative period.

E&M restrictionModifier 79 should not be appended to Evaluation and Management (E&M) codes on CMS-1500 claims.

Billing and Documentation Requirements

Policy Summary

PayerPremera Bluecross

PolicyModifier 79 Unrelated Procedure/Service by Same Provider during Postoperative Period

Policy CodePolicy CP.PP.147.v3.0

Change TypeClarification and documentation requirement

Effective Date

Next Review Date

Key ActionAppend modifier 79 to a surgical service on CMS-1500 or 837P only when the subsequent surgical procedure is completely unrelated to the original surgery and documented as such.

SourceLink

On This Page

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Billing Rule

Prior authorization / Billing rule: Use Modifier 79 only for completely unrelated subsequent surgeries

Append Modifier 79 to a surgical service on CMS-1500 or 837P only when the subsequent surgical procedure is completely unrelated to the original surgery; ensure the patient medical record clearly documents that the subsequent procedure is unrelated. Do not use modifier 79 for procedures following an initial procedure with a 0-day global period; it is appropriate following procedures with 10-day or 90-day global periods. Modifier 79 must not be appended to Evaluation and Management (E&M) codes on CMS-1500 claims. If the subsequent surgery is related and requires a return to the operating room by the same provider, bill with modifier 78 instead. Note that modifiers 58, 78 and 79 are mutually exclusive and do not bypass usual fee adjustments (multiple procedure, bilateral, assistant surgeon, etc.).

Medical record must clearly indicate the subsequent procedure is unrelated and typically linked to a different diagnosis. [[cited]]
Do not apply Modifier 79 after an initial procedure with a 0-day global period; applicable after 10-day or 90-day global periods per CMS. [[cited]]
Do not append Modifier 79 to E&M codes on CMS-1500 claims.
If the subsequent surgery is related and requires return to the OR by the same provider, use Modifier 78 instead.
Modifiers 58, 78 and 79 are mutually exclusive and do not bypass multiple procedure, bilateral, assistant surgeon, or other fee adjustments.

Key Definitions

Modifier 79 — definition

Definition (Modifier 79)Indicates a completely unrelated procedure or service by the same physician or other qualified healthcare professional during the postoperative period of a prior surgery; documentation in the medical record must clearly indicate the subsequent procedure is unrelated.

Diagnosis linkThe new unrelated procedure is usually linked to a different diagnosis.

Billing contextAppend modifier 79 to a surgical service on CMS-1500 or 837P only when the subsequent procedure is unrelated to the original surgery.

Mutually exclusive modifiers (58, 78, 79)

Mutual exclusivityModifiers 58, 78 and 79 cannot be billed together on the same procedure code; only one may be appended.

Do not bypass adjustmentsModifiers 58, 78 and 79 do not bypass usual multiple procedure, bilateral, assistant surgeon, or other fee adjustments.

Use guidanceStaged or pre-planned procedures should be billed with modifier 58; use modifier 78 for related return-to-OR procedures; modifier 79 is for unrelated procedures.