Anesthesia Coding Alert

The answer might surprise you

You know the routine: Your practitioner provides anesthesia for an out-of-the-norm case - during a child's MRI. You automatically append modifier -23 (Unusual anesthesia) to the procedure code and move on to the next claim. But before you go too far, take a closer look at the documentation - that's your tip-off to whether appending modifier -23 will actually trigger a denial, not a payment, for this service.

Dig Into the Descriptor

CPT's front-cover descriptor of modifier -23 seems basic enough by simply stating, "Unusual anesthesia." Its explanation in Appendix A, however, gives more details that you should consider:
 
"Occasionally, a procedure, which usually requires either no anesthesia or local anesthesia, because of unusual circumstances must be done under general anesthesia. This circumstance may be reported by adding the modifier -23 to the procedure code of the basic service."
 
Cases such as anesthesia during a child's MRI definitely meet the general criteria of "unusual circumstances." But because the more detailed explanation specifically refers to the use of general anesthesia, questions arise when the physician administers MAC (monitored anesthesia care) for the case. MAC usually involves sedation, but the patient does not lose consciousness and therefore does not require airway protection (intubation) as a patient under general anesthesia does. The question is whether you can append modifier -23 when the physician administers MAC instead of general anesthesia.
 
Tip: Begin your coding quest by verifying whether the case involved general anesthesia or MAC. If the physician administers general anesthesia, your part is easy - simply append modifier -23 as expected. But if the physician actually used MAC instead, it's time to decide on your next best option.

MAC Option 1: Drop the Modifier

Because CPT's descriptor does specify that modifier  -23 applies to cases with general anesthesia, some coders recommend that you don't append modifier -23 when the physician uses MAC.
 
"If the anesthesiologist says that it is a MAC case, I would probably submit the claim without a modifier," says Joanne Mehmert, CPC, Joanne Mehmert & Associates LLC, Kansas City, Mo. "If the claim is denied, I would appeal with a brief explanatory note pointing out to the carrier that the need is based on the child's age."
 
Emma LeGrand, CPC, CCS, with New Jersey Anesthesia Associates in Florham Park agrees, with one exception: "If the physician documents that he provided MAC but the patient reached the state of unconsciousness that is considered general anesthesia, I would attach modifier -23," she says.

MAC Option 2: Use -23 With an Explanation

Your second option is to append modifier -23 with an explanation that the physician used MAC because of the patient's age (the explanation goes in Box 19 of a paper claim and the appropriate note field of an electronic claim). This may be the better route if you know that the carrier in question will deny the claim.
 
You don't know how a carrier will respond the first time you file this type of claim. Mehmert points out that once you have a history with the carrier you know how to handle the situation. "When the carrier denies it the first time based on medical necessity, then you know they are likely to deny subsequent claims," she says. That's when you might want to try submitting the claim with modifier  -23 the first time.
 
"I feel that this approach is worth trying," LeGrand says. "Perhaps the carrier will take the age factor into consideration. If possible, you should also try to submit a letter of medical necessity from the primary physician."

MAC Option 3: Consider Modifier -22 Instead

Some coders wonder if they should append modifier  -22 (Unusual procedural services) to these MAC cases instead of modifier -23. One drawback to this approach is that Medicaid in many states (such as New York) does not recognize modifier -22.
 
"I prefer using modifier -23, since it more specifically addresses anesthesia services," LeGrand says. Other coding experts agree, adding that they're hesitant to report modifier -22 in these cases because you only get additional payment for the service once you go through the appeals process - and even then the reimbursement isn't enough to warrant the extra work.

Help Your Claim Along With Carrier Know-How

As with many cases, knowing the carrier's guidelines should help you submit the claim correctly. For example, some Medicare carriers cover MAC for any condition in a pediatric patient under 12 years of age. Even when carriers deny the claim, they usually pay once you submit an appeal indicating the patient's age or other special circumstances and the fact that anesthesia was necessary to help the patient go through the procedure.
 
LeGrand uses her own group as an example. Their physicians provide pediatric anesthesia services for MRIs or other noninvasive procedures several times a week. "We usually submit the claim without modifier -23, and most of the pediatric MRIs are paid. However, if the claim is denied once, we resubmit with modifier -23 and notes, and the carrier pays."
 
Verify: Some carrier policies recognize that patients with certain conditions may require anesthesia when other patients would not. Many MAC policies only allow anesthesia in the presence of certain comorbidities, which means successful claims submission depends on using the correct ICD-9 code rather than a modifier. Always check your local carriers' policies to verify their guidelines.

Set Your Course by Frequency Guidelines

"If you don't have many claims of this nature, it isn't so burdensome to submit with no modifier and appeal a denial," Mehmert says. "On the other hand, a pediatric anesthesia practice may have many of these claims. In that case, reporting modifier -23 with an explanation is the more practical way to go."
 
Whether you append modifier -23 or not, Mehmert and other coders say you should definitely include documentation with the claim to let the carrier know that it's a MAC case.