Anesthesia Billing: What Exactly IS the AD Modifier, and When Should it be Used?

Anesthesia billing has many unique facets that make it different from other medical specialty billing.  One unique element is the use of modifiers that distinguish the provider of the service and the actions performed by the provider(s).  Currently, anesthesia billing practices use roughly 20 different modifiers in order to submit claims accurately.  One modifier that is being used more and more is the AD modifier.  The AD modifier is used in circumstances where an anesthesiologist is supervising (not medically directing) more than four concurrent anesthesia procedures simultaneously.

Q. How does the AD modifier affect the billing and reimbursement of the practice?

A. The AD modifier is reimbursed differently than medical direction. In the traditional 4:1 medical direction model (modifier QK), the anesthesiologist is reimbursed for fifty percent of the payment for each case and each CRNA (modifier QX) is reimbursed for fifty percent of their case. If the AD modifier is used, the anesthesiologist is not subject to the TEFRA rules, but must be present for each induction—at a minimum. If so, the anesthesiologist is reimbursed for 3 base units + 1 unit of time per case. The CRNA (modifier QX) is reimbursed for fifty percent of each respective case.

The AD modifier is used when:

-The anesthesiologist is involved in conducting more than four procedures concurrently.

-The anesthesiologist is performing other services while medically directing concurrent procedures. There are several exceptions to this requirement:

1. Addressing an emergency (of short duration) in the immediate area
2. Administering an epidural to ease labor pain
3. Periodic (not continuous) monitoring of an obstetrical patient
4. Receiving patients entering the operating suite for the next surgery
5. Checking or discharging patients in PACU
6. Handling scheduling matters

These exceptions do not apply if the anesthesiologist:

a) Leaves the operating suite for anything other than short durations,

b) devotes extensive time to an emergency case, or

d) is otherwise unavailable to respond to the immediate needs of surgical patient.

Please note: In the case of two anesthesia services claims for the same patient on the same date of service, and no medical direction/supervision modifiers are appended, only the first claim processed will be allowed. The second claim processed is subject to denial as services furnished by another provider.

If you have questions about anesthesia billing or compliance, give us a call. We’d be happy to provide a risk-free consultation.