Neurosurgery Coding Alert

Neurosurgeons undertaking time-intensive procedures can often benefit from a physician assistant (PA) serving as a surgical first assistant. However, insurer guidelines vary and receiving reimbursement is a challenge. Communicating with payers, obtaining preauthorization and appending the proper modifiers will reduce reimbursement headaches.
  
What and How Much

PAs are licensed healthcare professionals who may, under a physician's supervision, practice medicine in any setting (e.g., office, clinic or hospital), says Barbara Johnson, CPC, a coding expert with Loma Linda University Medical Group in California. In most cases PAs can, for instance, take a patient's history, perform a physical exam, order and interpret tests, provide patient follow-up (including hospital rounds), and assist during surgery. As such, a PA can allow the neurosurgeon to allot his or her time more efficiently.
 
A PA bills for his or her services with a personal identification number (PIN). Generally, reimbursement is 85 percent of the rate paid to a physician in the same circumstances, Johnson says. Reimbursement for physicians serving as surgical first assistants varies from 16 to 20 percent of the primary surgeon's fee, depending on the payer. For example, if the insurer pays a physician first surgical assistant 20 percent of the primary surgeon's fee of $100, or $20, a PA serving as first assistant for the same surgery would receive $17 ($20 x .85%).
 
Note: Services provided by a PA billing under his or her own PIN are distinct from services provided "incident to" physician services. Incident to services are billed under the physician's PIN, are reimbursed at 100 percent of the usual rate, and are governed by separate guidelines.
 
For more information on incident to billing, see Neurosurgery Coding Alert, December 2001, "Focus on ABNs and Incident To." 

Although surgical first assistants are useful in many neurosurgical procedures, including diskectomies, laminectomies, craniectomies and others, they are not appropriate for every surgery, Johnson notes. Section 15016 of the Medicare Carriers Manual specifies that an assistant at surgery will not be reimbursed "in a teaching hospital which has a training program related to the medical specialty required for the surgical procedure and has a qualified resident available." Only under special circumstances, i.e., a qualified resident is not available or the primary surgeon never uses residents, will Medicare pay for an assistant at surgery at a teaching hospital (see information on modifier -82, below).
 
Although national Medicare policy recognizes the role of licensed PAs as assistants at surgery, state practice laws vary. In some states, PAs cannot bill for their services at all, says Susan Callaway, CPC, CPS-C, an independent coding and reimbursement specialist in North Augusta, S.C. In addition, payers private and Medicare may specify their own guidelines for assistants at surgery. Preauthorization from the payer is sometimes required but is always advised. Be sure to get recommendations in writing.
 
Note: In 1998 the American College of Surgeons (ACS) and 13 surgical-specialty organizations "undertook a study on the need for a physician as an assistant at surgery for all procedures listed in the 'Surgery' section of the CPT." According to the ACS, "Each organization was asked to review codes applicable to their specialty and determine whether the operation required the use of a physician as an assistant at surgery (1) almost always, (2) almost never, or (3) some of the time." The results of this study are presented in a publication titled Physicians as Assistants at Surgery. Although slightly out-of-date, the publication is still a valuable resource. Physicians as Assistants at Surgery may be ordered from ACS by writing to 1640 Wisconsin Ave., N.W., Washington, DC 20007, or fax your request for a copy to 202-337-4271.

The PA serving as a surgery assistant bills the same CPT codes as the primary surgeon. To indicate that a PA provided the services, however, append modifier -AS (physician assistant, nurse practitioner, or clinical nurse specialist services for assistant at surgery) to claims for Medicare carriers and some third-party payers. Other third-party payers prefer modifier -80 (assistant surgeon), Callaway says. This modifier does not specifically indicate that the assistant surgeon was a PA, which could cause reimbursement delays. The best strategy is to contact the payer ahead of time to learn its particular requirements.
 
Documentation is also important, Callaway stresses. If the payer requires special credentialing of the PA, your claim must include evidence that the PA serving as surgical first assistant meets these requirements. A copy of the operative report explaining exactly how the PA assisted in the operating room, with a form letter explaining why the PA was needed, will further reduce delays and denials.
 
Modifiers -81 (minimum assistant surgeon) or -82 (assistant surgeon [when qualified resident surgeon not available]) are not generally appropriate for services provided by a PA surgical first assistant. Modifier -81 is only used when specifically required by a payer. Modifier -82 applies only in teaching hospitals where residents normally serve as surgical first assistants.
 
For instance, after receiving preauthorization for his services, a PA serves as surgical first assistant during a diskectomy for a Medicare patient. The primary surgeon codes 63075 (diskectomy, anterior, with decompression of spinal cord and/or nerve root[s], including osteophytectomy; cervical, single interspace). The PA reports 63075-AS under his own PIN, providing documentation outlining his role as an assistant. Based on the relative value units (RVUs) assigned to 63075 ($36.97 fully implemented facility RVUs) and the current national average conversion rate ($36.1992), payment for the primary surgeon is about $1,340. Medicare reimburses assistants at surgery at 16 percent of the rate paid to the primary surgeon. The PA receives 85 percent of this amount, or about $182, for assisting during the diskectomy ($1,340 x .16 x .85).
 
For a private payer, the same guidelines apply, but
the proper coding may instead be 63075-80 and reimbursement may vary.