List Of Anesthesia Modifiers | Descriptions & Billing Guide (2022)

Anesthesia modifiers can be used to clarify a CPT code for a service that is billed. The modifiers can be used to alter a service without having to change a CPT code. This article covers all the modifiers that can be used for anesthesia services.

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1. What Are Anesthesia Modifiers?
2. How To Bill Anesthesia Modifiers
3. Position Of Modifiers On Anesthesia Claims
4. Reimbursement
5. Anesthesia Pricing Modifiers
   1. Modifier AA
   2. Modifier AD
   3. Modifier QK
   4. Modifier QS
   5. Modifier QX
   6. Modifier QY
   7. Modifier QZ
   8. Modifier 33
   9. Modifier PT
6. Anesthesia Physical Status Modifiers
   1. Modifier P1
   2. Modifier P2
   3. Modifier P3
   4. Modifier P4
   5. Modifier P5
   6. Modifier P6
7. Anesthesia Informational Modifiers
   1. Modifier QS
   2. Modifier G8
   3. Modifier G9
   4. Modifier GC

1. What Are Anesthesia Modifiers?

Anesthesia modifiers also add information to a code and eliminate or prevent unbundling or duplicate billing. They increase code consistency, editing, reimbursement accuracy, and capturing data.

Make sure to submit the anesthesia modifiers correctly on claims that are committed to the national government services. Incorrect claims will need manual intervention and cause delays.

Modifier QS, Modifier G8 and Modifier G9 are informational only and do not affect payment. Informational modifiers must be used in the second modifier position, in conjunction with a pricing anesthesia modifier in the first modifier position.

2. How To Bill Anesthesia Modifiers

Anesthesia procedures are billed with the CPT codes that can be found in the manual in the Anesthesia section.

Reimbursement for surgical anesthesia services is calculated based on a conversion factor, time units of 15 minutes, and base units.

A flat fee is used for reimbursement for maternity-related procedures and moderate sedation. General anesthesia for vaginal delivery is an exception.

Report minutes on anesthesia claims. Only leave it out if the policy states otherwise.

Bill surgical anesthesia services with the following anesthesia modifiers:

• Modifier QZ: CRNA service without medical direction by an anesthesiologist.
• Modifier QX: CRNA service with direction by an anesthesiologist.
• Modifier QK: Anesthesiologist Medical direction of two, three, or four concurrent anesthesia procedures involving qualified individuals.
• Modifier QY: Anesthesiologist Medical direction of one CRNA.
• Modifier AA: Anesthesiologist Anesthesia services performed personally by the anesthesiologist.

The following is an explanation of billable modifier combinations:

• Legitimate modifier combinations: Modifier QK and QX QY and Modifier QX
• Modifiers that need a partner: Modifier QK, Modifier QX, and Modifier QY.
• Modifiers that can stand alone: Modifier AA and Modifier QZ.

3. Position Of Modifiers On Anesthesia Claims

Document anesthesia modifier in the first position to indicate whether the service was medically directed, medically supervised, or personally performed.

Claims submitted without anesthesia modifiers in the correct position can result in rejections or processing delays.

4. Reimbursement

Below are the maximum allowable fees for anesthesia services billed as MD supervision of a CRNA for Blue Cross and Blue Shield of Texas and HMO Blue Texas.

• Modifier QY reimbursement: $325.52 (MD Medical Direction of a CRNA).
• Modifier AD reimbursement: $162.76 (MD supervision of a CRNA).
• Modifier QK reimbursement: $310.01 (MD Medical Direction of a CRNA).

Anesthesia modifiers billed to Medicare must include at least one of the modifiers below.

5. Anesthesia Pricing Modifiers

An anesthesia pricing modifier has to be listed in the first position in order to receive reimbursement.

5.1 Modifier AA

AA Modifier description: Anesthesia services are personally performed by an anesthesiologist.

Payment for modifier AA for anesthesia claims is 100% allowable. This modifier allows full fee schedule reimbursement.

5.2 Modifier AD

AD Modifier description: Medical direction of 2, 3, or 4 concurrent anesthesia procedures involving qualified individuals.

Modifier AD limits payment to 50% of the amount that would have been allowed if personally performed by an anesthesiologist or nonsupervised CRNA.

5.3 Modifier QK

QK Modifier description: Medical direction of two, three, or four concurrent anesthesia procedures involving qualified individuals.

Read more about Modifier QK in this billing guide.

5.4 Modifier QS

QS Modifier description: Monitored anesthesia care service.

Read more about Modifier QS in this billing guide.

5.5 Modifier QX

QX Modifier description: CRNA service with medical direction by an anesthesiologist.

Read more about Modifier QX in this billing guide.

5.6 Modifier QY

QY Modifier description: Anesthesiologist medically directs one CRNA.

Read more about Modifier QY in this billing guide.

5.7 Modifier QZ

QZ Modifier description: CRNA service without medical direction by an anesthesiologist.

Read more about Modifier QZ in this billing guide.

5.8 Modifier 33

33 Modifier description: Preventive Services.

Medicare deductible and coinsurance will be waived if modifier 33 is appended to CPT 00810 for anesthesia services.

5.9 Modifier PT

PT Modifier description: A colorectal cancer screening test that led to a diagnostic procedure. This modifier is appended to anesthesia CPT code 00810 and will waive the Medicare deductible.

6. Anesthesia Physical Status Modifiers

If physical status modifiers P3, P4, or P5 are billed, the full unit value for these physical status modifiers will be reimbursed even if the obstetrical delivery total maximum allowable points have been met.

6.1 Modifier P1

P1 Modifier description: A normal healthy patient.

6.2 Modifier P2

P2 Modifier description: A patient with mild systemic disease.

6.3 Modifier P3

P3 Modifier description: A patient with severe systemic disease.

One additional time unit is allowed.

6.4 Modifier P4

P4 Modifier description: A patient with severe systemic disease that is a constant threat to life.

Two additional time units are allowed.

6.5 Modifier P5

P5 Modifier description: A moribund patient who is not expected to survive without the operation.

Three additional time units are allowed.

6.6 Modifier P6

P6 Modifier description: A declared brain-dead patient whose organs are being removed for donor purposes.

7. Anesthesia Informational Modifiers

Anesthesia informational modifiers shall be placed in the second modifier position.

7.1 Modifier QS

QS Modifier description: Monitored anesthesia care (MAC).

7.3 Modifier G9

G9 Modifier description: MAC for a patient who has a history of severe cardiopulmonary condition and may be used in lieu of modifier QS.

7.4 Modifier GC

GC Modifier description: Performed by a resident under the direction of a teaching physician: the provider must also use one of the other pricing modifiers in the first modifier position.