Modifier QX- CRNA Service With Medical Direction

Identifies anesthesia services provided by a certified registered nurse anesthetist under the medical direction of a physician.

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What Is Modifier QX?

Modifier QX is used when a Certified Registered Nurse Anesthetist (CRNA) provides anesthesia services under the medical direction of a physician.

The modifier identifies the CRNA's portion of a medically directed anesthesia service and is reported on the anesthesia claim submitted for the CRNA's services.

CMS currently identifies QX as an anesthesia payment modifier for CRNA services furnished with physician medical direction.

When one CRNA is medically directed by an anesthesiologist, the CRNA generally reports QX while the anesthesiologist reports Modifier QY.

When to Use Modifier QX

CRNA Provides Anesthesia: The anesthesia service is personally furnished by a CRNA.

Physician Medical Direction: A physician provides qualifying medical direction of the CRNA's anesthesia service.

Medical Direction Requirements Met: The physician satisfies applicable Medicare requirements for medical direction.

Anesthesia Time Reported: Actual anesthesia time is accurately documented and reported.

CRNA Claim: QX is appended to the appropriate anesthesia code on the claim for the CRNA's service.

When NOT to Use Modifier QX

No Physician Medical Direction: Modifier QZ generally applies when a CRNA furnishes anesthesia without physician medical direction.

Personally Performed by Anesthesiologist: Modifier AA may apply when the anesthesiologist personally performs the anesthesia service.

Physician Portion of the Service: QX identifies the CRNA's service, not the medically directing physician's service.

Medical Supervision Rather Than Direction: Different modifier requirements apply when the physician does not satisfy Medicare's medical direction requirements.

Monitored Anesthesia Care Alone: Modifier QS identifies MAC but does not replace the appropriate anesthesia payment modifier.

Billing Example

A patient undergoes surgery requiring anesthesia.

A CRNA provides the anesthesia service while an anesthesiologist satisfies Medicare's requirements for medical direction.

The CRNA reports the appropriate anesthesia code with Modifier QX.

When the anesthesiologist is medically directing only that one CRNA, the anesthesiologist generally reports the corresponding anesthesia service with Modifier QY. CMS recognizes this QX/QY billing relationship.

Documentation Requirements

Anesthesia Record: Maintain a complete record of the anesthesia service provided.

Medical Direction: Documentation should support the physician's qualifying medical direction.

Anesthesia Time: Record accurate anesthesia start and stop times.

CRNA Participation: Documentation should identify the CRNA who furnished the anesthesia service.

Patient Monitoring: Record appropriate monitoring and clinical management throughout anesthesia.

Medical Necessity: Documentation should support the anesthesia service and underlying procedure.

Billing and Claim Considerations

Modifier QX is an anesthesia payment modifier, unlike Modifier QS, which is informational.

CMS uses QX to identify anesthesia furnished by a CRNA with physician medical direction.

When a single anesthesia case involves both an anesthesiologist providing medical direction and a CRNA furnishing the anesthesia service, Medicare generally recognizes separate portions of the service. The CRNA reports QX, while the anesthesiologist reports the applicable medical-direction modifier.

The claim should also contain accurate anesthesia time because Medicare anesthesia payment calculations incorporate base units, time units, and the applicable anesthesia conversion factor.

Common Billing Mistakes

Using QX Without Medical Direction: QX requires qualifying physician medical direction.

Confusing QX With QZ: QZ identifies CRNA anesthesia services furnished without physician medical direction.

Reporting QX for the Physician: QX identifies the CRNA's portion of the medically directed service.

Missing Anesthesia Time: Inaccurate or missing anesthesia time can affect claim processing and payment.

Incorrect Physician Modifier: The medically directing physician must report the modifier appropriate to the specific anesthesia arrangement.

Incomplete Documentation: Records fail to demonstrate the CRNA service or physician medical direction.

Common Denial Reasons

Medical Direction Not Supported: Documentation does not establish qualifying physician medical direction.

Incorrect Modifier: QZ or another anesthesia modifier better represents the service.

Missing Anesthesia Time: Required anesthesia time information is incomplete or inaccurate.

Provider Information Conflicts: Claim information does not support the reported CRNA and physician relationship.

Documentation Is Incomplete: The anesthesia record does not support the billed service.

Coverage Requirements Not Met: The underlying anesthesia service does not satisfy applicable Medicare requirements.

Modifier QX vs. Modifier QZ

Modifier QX: CRNA anesthesia service furnished with medical direction by a physician.

Modifier QZ: CRNA anesthesia service furnished without medical direction by a physician.

The key difference is whether qualifying physician medical direction is provided. CMS currently recognizes both as CRNA anesthesia payment modifiers.

Modifier QX vs. Modifier QY

Modifier QX: Reported for the CRNA's service when anesthesia is medically directed by a physician.

Modifier QY: Used by the anesthesiologist for medical direction of one CRNA.

When an anesthesiologist medically directs a single CRNA, QX and QY can represent the respective portions of the same anesthesia case.

Frequently Asked Questions

Is Modifier QX reported by the CRNA or the anesthesiologist?
QX identifies the CRNA's anesthesia service furnished with physician medical direction. The physician reports the appropriate medical-direction modifier.

Is Modifier QX used when a CRNA works without medical direction?
No. Modifier QZ identifies CRNA anesthesia services furnished without physician medical direction.