Modifier AA — Anesthesia services performed personally by anesthesiologist

AAHCPCS Level II

Anesthesia services performed personally by anesthesiologist

Usage notes: Append to an anesthesia code when the anesthesiologist personally performed the entire anesthesia service without medical direction of others.
Common mistakes: Using AA when a CRNA was actually medically directed by the anesthesiologist — that scenario uses QY/QX rather than AA.

Related modifiers

A1Dressing for one wound A2Dressing for two wounds A3Dressing for three wounds A4Dressing for four wounds A5Dressing for five wounds A6Dressing for six wounds A7Dressing for seven wounds A8Dressing for eight wounds

Frequently asked questions

What does modifier AA mean?

Anesthesia services performed personally by anesthesiologist

When do I use modifier AA?

Append to an anesthesia code when the anesthesiologist personally performed the entire anesthesia service without medical direction of others.

What's a common mistake with modifier AA?

Using AA when a CRNA was actually medically directed by the anesthesiologist — that scenario uses QY/QX rather than AA.

HCPCS modifier data from CMS. CPT® is a registered trademark of the American Medical Association — CPT modifier descriptions are not included on this site. Always verify codes with authoritative sources before making billing decisions.