Billing for Four or More Simultaneous Anesthesia Procedures


Medicare has determined that providers are not routinely billing with modifiers AD and 23 when performing more than four concurrent anesthesia procedures.

Payment is allowed for three base units per procedure when an anesthesiologist is involved in furnishing more than four anesthesia procedures concurrently, or when an anesthesiologist is performing other services while directing the concurrent procedures. An additional time unit is allowed only if the documentation supports the physician was present at induction.

When billing for more than four concurrent anesthesia procedures, and to ensure proper payment, please follow these guidelines.

Append modifiers AD and 23 with the anesthesia procedure codes.
No need to submit documentation with the claim. Modifiers AD and 23 will attest to proper documentation on file to support that the provider was present on induction.

Modifiers defined

AD - Medical supervision by a physician, more than four concurrent anesthesia procedures.
23 - Unusual anesthesia.

Medicare does not pay for more than three base units unless the anesthesia procedure is billed with modifiers AD and 23. Payment for claims submitted with modifier AD only will be made for three base units.


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