US · guidance
CMS Pub. 100-04, ch. 12, § 140.4.2
Qualified Nonphysician Anesthetist and an Anesthesiologist in
a Single Anesthesia Procedure
(Rev. 3747; Issued: 04-14-17; Effective: 01-01-17; Implementation: 05-15-17)
Where a single anesthesia procedure involves both a physician medical direction
service and the service of the medically directed qualified nonphysician anesthetist, the
payment amount for the service of each is 50 percent of the allowance otherwise
recognized had the service been furnished by the anesthesiologist alone. For the single
medically directed service, the physician will use the QY modifier and the qualified
nonphysician anesthetist will use the QX modifier.
In unusual circumstances when it is medically necessary for both the CRNA and the
anesthesiologist to be completely and fully involved during a procedure, full payment for
the services of each provider is allowed. The physician would report using the AA
modifier and the CRNA would report using the QZ modifier. Documentation must be
submitted by each provider to support payment of the full fee.
History
(Rev. 3747; Issued: 04-14-17; Effective: 01-01-17; Implementation: 05-15-17)
Provenance
- Source
- cms.gov
- Retrieved
- 2026-08-25
- Edition
- iom-2026-08-25
- Content hash
c3a8a9305d9557862aed783f9e34b73a81653811f6da34d4bbdd13ef3c8eb780
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