CO-194 denial code
Anesthesia performed by the operating physician or assistant
How to fix it
Confirm who provided anesthesia. Where an independent provider did, correct the billing provider and resubmit.
How to prevent it
Ensure anesthesia is billed under the correct rendering provider, particularly for procedural sedation.
In practice
A surgeon administers moderate sedation during a procedure and bills an anaesthesia code alongside the surgical code. The claim returns CO-194.
Anaesthesia provided by the operating physician is not separately payable, because the work is considered part of the procedure the surgeon is already being paid for.
Where an independent anaesthesia provider delivered the service, the billing provider on the claim is wrong and correcting it resolves the denial. Where the surgeon genuinely provided it, the service is not separately billable regardless of the effort involved.
What sits behind it
Moderate sedation is the frequent source of confusion. Some procedures include sedation in their value and some do not, and the distinction is published rather than inferred. Billing sedation alongside a procedure that already includes it produces this code every time.
The rule serves a coherent purpose. Paying a surgeon separately for anaesthesia they administer during their own procedure would pay twice for overlapping work, which is the same principle underlying the bundling edits generally.
Where an anaesthesia group and a surgical practice share billing infrastructure, the claim can be built under the wrong rendering provider by configuration rather than by decision. Checking who is listed before submission is a small step that prevents a denial requiring correction and resubmission.
Related codes
Terms used here — NCCI Edits · Modifier · CPT Code
How we handle it — Medical Coding · Denial Management · Claims Management
Primary sources
The rules behind CO-194, at the bodies that publish them.
- NCCI Policy Manual for Medicare Services (opens in a new tab)
Centers for Medicare & Medicaid Services — The reasoning behind the edits, chapter by chapter. Where the edit files tell you two codes conflict, this explains why — which is what an appeal has to address.
- National Correct Coding Initiative (NCCI) edits (opens in a new tab)
Centers for Medicare & Medicaid Services — The procedure-to-procedure and medically-unlikely edits behind most bundling denials. Checking these before submission prevents the denial entirely.
- Medicare Claims Processing Manual (opens in a new tab)
Centers for Medicare & Medicaid Services — The operative manual for how Medicare claims must be coded, submitted, adjusted and appealed. When a payer policy and a vendor's advice disagree, this settles it.
Looking for a different code? Search all 190 CARC and RARC codes
Questions about CO-194
Not for anaesthesia administered during their own procedure, because that work is already valued within the surgical payment. A surgeon providing anaesthesia for a different provider's case is in a different position and bills as the anaesthesia provider.
It depends on whether the procedure's value already includes it, which is published rather than inferred. Some procedures include sedation and some do not, and billing it alongside one that does produces this denial consistently.
Frequently, particularly where an anaesthesia group and a surgical practice share billing infrastructure. The claim can be built under the surgeon by configuration rather than by decision, so checking the rendering provider before submission is worth the moment it takes.
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