Chart Talk ~ Anesthesia Coding Conversations

The Procedure Is Listed — But Where Is the Documentation?

You are reviewing an anesthesia claim. In addition to the anesthesia service, you see another CPT code. Maybe it’s an arterial line, or a central venous catheter, a separately reported TEE service, or maybe it’s ultrasound guidance associated with another procedure.

At first glance, the additional code may seem perfectly reasonable for the type of case you are reviewing. But an auditor shouldn’t stop with, “Yes, they probably did that.” The next question is “Where is the documentation supporting it?”

Welcome to Anesthesia Audit Red Flag #3.

There are many procedures and services anesthesia professionals routinely perform in connection with anesthesia care. Depending on the circumstances and applicable coding requirements, certain services may be separately reportable from the anesthesia service. Examples may include arterial catheter insertion, central venous catheter insertion, pulmonary artery catheter insertion, certain TEE services, ultrasound guidance when separately reportable and appropriately documented, or other procedures performed by the anesthesia professional. The fact that a procedure is commonly performed during a particular type of case doesn’t establish that it was performed by the anesthesia provider in this case and it certainly doesn’t replace the documentation required to support the code. Familiarity with the procedure should never become a substitute for documentation.

Imagine reviewing a cardiac anesthesia record and seeing an arterial line documented throughout the case blood pressures are recorded from it, the waveform is referenced, and the line was clearly present. Does that prove that the anesthesia professional inserted it? No. It proves the patient had an arterial line and that distinction matters. The line may have been inserted by the anesthesia professional, but it could also have been inserted by another provider or already been present. If an insertion service is separately reported, the documentation should support who performed that insertion. An auditor shouldn’t infer performance simply because the device was subsequently used.

Suppose you see CPT 36620 reported for arterial catheterization. Your next step shouldn’t simply be “That’s the arterial line code. Looks good.” Look for the documentation supporting the procedure. Does the record identify the procedure performed, the provider who performed it, the insertion site when relevant, the technique or other required procedural details, successful placement or completion, or other documentation necessary under applicable coding or payer requirements? The exact documentation needed will depend on the service and applicable guidance, but the fundamental audit principle remains, A code on the claim cannot serve as its own documentation.

This is another area where auditors need to distinguish between evidence that something existed and documentation that a billable procedure was performed. An anesthesia record may contain A-Line, CVP, TEE, and Ultrasound.That may point you in the right direction, but what exactly does the entry establish? For example, does “A-Line” mean the anesthesia provider inserted an arterial catheter, the patient already had one, the line was monitored, someone attempted insertion, or it was merely part of a templated section of the anesthesia record? The auditor needs enough documentation to determine what actually occurred.

This can be particularly important when several professionals are involved in the patient’s care. The medical record may establish that a central venous catheter was inserted, but who inserted it? The anesthesiologist, the CRNA, another physician, or a member of the surgical team? Was one provider assisting while another actually performed the procedure? Before accepting a separately reported service, the auditor should be able to connect the service to the provider or practitioner for whom it is being billed under the applicable rules. Don’t confuse “performed during anesthesia” with “performed by anesthesia.”

Ultrasound documentation deserves special attention. Seeing the words “ultrasound used” doesn’t automatically mean that a separately reportable ultrasound guidance service is supported. When ultrasound guidance is separately reportable, the documentation requirements associated with that service must be satisfied. Depending on the code and circumstances, that may include specific documentation related to real-time visualization and image documentation or retention. There is another important question, is ultrasound guidance already included in the primary procedure code? Not every use of ultrasound creates another separately reportable service. An auditor should verify both; Is separate reporting permitted and does the documentation satisfy the requirements?

Transesophageal echocardiography can create particularly interesting anesthesia audit questions. An anesthesia professional may use TEE during a complex cardiac procedure but simply documenting that TEE was used doesn’t automatically tell the auditor what TEE service, if any, is separately reportable. The auditor may need to determine, who inserted the probe, who performed the examination, who interpreted the study, was a report generated, what components of the service were actually performed, was the service diagnostic or used for monitoring, does the documentation support the specific TEE code or component reported, and do applicable coding rules permit separate reporting in the circumstances? TEE auditing is an excellent example of why an auditor can’t stop at the procedure name. The words “TEE performed” may only be the beginning of the review. Have you reviewed the CPT Assistant Article dated which changes the documentation requirements for CPT Codes 93320 and 93325?  You need to take a look and make sure that templates are updated to reflect the required documentation. This can be found in the March 2026; Volume 35: Issue 3. 

The same procedure appears on more than one claim.  Another question worth asking is Did someone else bill for this too? When auditing separately reportable services, especially in complex cases involving multiple providers, review for possible duplicate reporting when appropriate. Two claims associated with the same patient, date, and procedure don’t automatically represent duplicate billing. There may be legitimate reasons for separate reporting of different professional components or services, but it is a red flag worth investigating.

The Auditor Has Two Questions to Answer when reviewing a separately reported anesthesia-related service, don’t ask only, “Was the procedure performed,” Ask: 1. Does the documentation support that this provider performed the service being reported and 2. Is the service separately reportable under the applicable coding and payer rules? Those are different questions. Excellent documentation doesn’t make a bundled service separately billable and a service that is normally separately reportable still needs documentation supporting that it was actually performed. You need both.

🔎 Auditor’s Mini-Challenge

You are reviewing an anesthesia claim for a major surgical procedure. The claim includes Anesthesia service and CPT 36620 — Arterial catheterization. The anesthesia record shows continuous arterial blood pressure readings throughout the case. In the vascular access section, you see “A-Line: Left radial.” You cannot locate a separate procedure note or other documentation clearly identifying who inserted the arterial catheter. 

What should the auditor do?

A. Accept 36620 because arterial pressure was monitored throughout the case.

B. Accept 36620 because arterial lines are commonly placed by anesthesia.

C. Deny 36620 automatically because there is no separate procedure note.

D. Review the complete record and applicable documentation requirements to determine whether there is sufficient documentation supporting the insertion and the provider who performed it.

The best auditing approach is D.

Notice what we didn’t do. we didn’t assume it was supported and we didn’t assume it wasn’t supported. We followed the red flag.

Documentation of Presence ≠ Documentation of Performance

This is the pearl I want anesthesia coders and auditors to remember from this discussion, A device being present doesn’t necessarily establish who placed it. An arterial line on the monitor doesn’t prove who inserted the arterial catheter. A central line being used doesn’t prove who placed it. TEE images don’t automatically establish who performed and interpreted the service. An ultrasound machine being used doesn’t automatically support separately reporting ultrasound guidance. The auditor must connect the code to the service, the service to the documentation, and the documentation to the provider.

🚩 Auditor’s Takeaway

Separately reportable anesthesia-related services can easily become an audit risk when the procedure seems so routine that no one stops to ask whether the documentation actually supports it. Don’t assume, don’t code from expectation. and don’t let the presence of a CPT code convince you that the documentation must exist somewhere. Go find it. Ask: What was performed, who performed it, where is it documented, does the documentation support the specific code, is separate reporting permitted, and could I defend this service from the medical record?

Because when you see an additional procedure on an anesthesia claim, your auditor’s question should always be “The procedure is listed—but where is the documentation?”

Next: Anesthesia Audit Red Flag #4
Postoperative Pain Block or Primary Anesthetic?

A block was performed, but before we ask what code, we’re going to ask something even more important; Why was the block performed?

Chart Talk ~ Anesthesia Coding Conversations
Anesthesia Coding • Auditing • Compliance • Education

Educational content is intended for informational purposes only and is not a substitute for current authoritative guidance. Always consult current CPT®, CMS, NCCI, Medicare Administrative Contractor, payer-specific, and other applicable guidance when making coding, billing, auditing, or compliance determinations.