When to Use Modifier -58 and -78 With Example

Your question: I have a chart that I’m coding. Pt had the CPT 35800 done on 2/1/26 but then due to bleeding around the trach site, the ENT doctor was called back to the patient on 2/2/26 to have a flexible fiber optic tracheoscopy inserted and cuff reinflated. Can I bill out the CPT 31575 for 2/2/26 after coding CT 35800 BEFORE the patient needed a new trach the very next day? If so what modifier do I use? If not, why?

Microsoft Copilot: Let’s walk through it cleanly and defensibly.

Short Answer

Yes, CPT 31575 may be separately reportable on 2/2/26 — but only if documentation supports that it was a distinct, medically necessary diagnostic service.
If it is billable, modifier ‑58 is the most appropriate modifier in most cases, not ‑59.

Step‑by‑Step Analysis

1. Relationship Between CPT 35800 and 31575

CPT 35800 = exploration for postoperative hemorrhage, thrombosis, or infection.
CPT 31575 = diagnostic flexible fiberoptic laryngoscopy/tracheoscopy.

These are:

Different CPT families
Different anatomic focus
Different intent (surgical control of bleeding vs diagnostic airway evaluation)

They are not inherently bundled by CPT or NCCI.

2. Timing Matters — This Was the Next Day

The scope was performed:

On a different date of service (2/2/26)
After the initial surgical intervention
Due to a new or ongoing clinical issue (bleeding around the trach site)

That alone removes same‑session bundling concerns.

3. Was the Scope “Routine Post‑Op Care”?

This is the key question.

31575 is NOT billable if:

The scope was merely to check placement
It was part of routine post‑op airway management
It was incidental to managing the trach without diagnostic intent

31575 IS billable if documentation shows:

Evaluation of bleeding source
Assessment of airway integrity
Visualization to determine cause of complication
Medical decision‑making based on findings

Diagnostic intent is critical

Modifier Selection — What to Use (and What NOT to Use)

This is the best fit when:

The patient is in the post‑operative period
The service is related to the original condition
The procedure was planned or medically necessary due to evolving complications

Modifier ‑58:

Allows payment
Resets the global period
Signals this was not routine post‑op care

This aligns with CPT guidance for post‑op diagnostic procedures.

🚫 Why NOT Modifier ‑59?

Modifier ‑59 is for:

Same‑day
Same session
Bundled procedures

This was:

A different date
A post‑op evaluation
Not an NCCI edit issue

Using ‑59 here would be incorrect and audit‑vulnerable.

🚫 Why NOT Modifier ‑78?

Modifier ‑78 applies to:

Return to the OR
Unplanned surgical procedures

A bedside or procedural scope does not qualify as a return to the OR.

Documentation Must Include

To safely bill 31575 ‑58, the note should clearly state:

Reason ENT was called back
Diagnostic purpose of the scope
Findings (bleeding source, cuff status, airway condition)
Medical decision‑making based on findings
That this was not routine trach care

Final Coding Recommendation

Date	CPT	Modifier	Billable?	Rationale
2/1/26	35800	—	Yes	Primary surgical intervention
2/2/26	31575	‑58	Yes, if documented	Post‑op diagnostic evaluation due to complication

This is where auditors and payers love to deny — so let’s be very explicit about what flips CPT 31575 from billable to non‑billable in your scenario.

I’ll break this into clear failure points so you can audit the note against each one.

1️⃣ It Becomes Non‑Billable If the Scope Was Routine Post‑Op Airway Management

31575 is NOT payable when the scope is used simply to:

Check trach position
Confirm patency
Assist with cuff reinflation
Perform routine airway surveillance

If the documentation reads like:

“Flexible scope used to visualize trach and reinflate cuff”
“Scope passed to assess airway and adjust cuff”
“Routine post‑op airway check”

➡️ That is considered inherent post‑operative care following a trach‑related complication and is bundled into the global of 35800.

Key audit phrase that kills it:

“Used to assist with management”
instead of
“Used to evaluate cause of bleeding / airway compromise”

2️⃣ It’s Non‑Billable If There Is No Diagnostic Intent

CPT 31575 is a diagnostic code, not a therapeutic one.

It becomes non‑billable if:

No diagnostic question is stated
No pathology is being evaluated
No findings are documented beyond “visualized”

Missing elements that trigger denial:

No stated reason why visualization was required
No findings (bleeding source, edema, erosion, displacement)
No medical decision‑making tied to the scope

If the scope didn’t change or guide care, payers will say:

“This was incidental to post‑op management.”

3️⃣ It’s Non‑Billable If the Bleeding Is Considered Expected Post‑Op Course

If documentation implies:

Mild oozing
Expected post‑trach bleeding
Normal post‑surgical findings

Then the scope is considered:

Monitoring
Observation
Routine follow‑up

➡️ Expected sequelae = not separately payable

To bill 31575, the bleeding must be framed as:

Concerning
Unanticipated
Requiring diagnostic evaluation

4️⃣ It’s Non‑Billable If the Scope Was Solely to Fix a Problem

This is subtle but important.

If the scope was used only to:

Reinflate the cuff
Adjust the trach
Confirm resolution after intervention

Then it’s therapeutic assistance, not diagnostic.

Diagnostic first → intervention second = billable
Intervention only = bundled

5️⃣ It’s Non‑Billable If Documentation Suggests It Was Part of the Original Procedure’s Aftercare**

If the note ties the scope directly back to:

“Post‑op check from yesterday’s surgery”
“Follow‑up from exploration”
“Continued management of surgical site”

Then payers will argue:

“This is routine post‑operative management within the global period.”

Even though it’s a different date, global rules still apply.

6️⃣ It’s Non‑Billable If the Wrong Modifier Is Used

Even when the service could be billable, it will deny if:

Modifier ‑59 is used instead of ‑58
No modifier is appended at all
Modifier ‑78 is incorrectly applied

Payers expect ‑58 when:

Diagnostic evaluation occurs during the post‑op period
It’s related to the original condition
It’s medically necessary due to complication

Wrong modifier = automatic denial.

Quick Audit Checklist (Use This on the Note)

31575 is NOT billable if any of the following are true:

No diagnostic question stated
Scope used only to assist cuff reinflation
Findings not documented
Bleeding described as expected or minimal
Scope described as routine post‑op care
No medical decision‑making tied to scope
Modifier ‑58 not supported or not used

Bottom Line

The scope lives or dies on documentation intent.
Same patient, same timeline — one sentence can flip this from payable to bundled.

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