No matter the specialty, physicians need to be familiar with the coding conventions for reporting the services they commonly perform. Anesthesiology is no exception. In this chapter we briefly discuss the history of the anesthesia coding system and cover the codes that describe anesthesia care. In Chapter 209 we will learn about the unique anesthesia payment system.

Before the 1960s, the anesthesiology profession, like medicine as a whole, had no “system” for reporting its services. Physicians billed their patients directly for the services rendered. Each physician or group established its own fees using individual determinations of the value of the care provided. A senior member of my former group recalls that in the early days of her practice, she charged a fixed percentage of the surgical fee. Although this system was elegant in its simplicity, those who provide anesthesia know that the relationship between surgical effort and anesthesia effort is highly variable.

The explosive growth of third-party payers in the late 1950s and 1960s created a need for better ways to both describe and define the value of anesthesia care. In the early 1960s, trailblazers in California developed the California Relative Value Guide, a systematic listing of anesthesia services and recommended values for each service. Only a few years later, the American Society of Anesthesiologists (ASA) adopted much of the California guide and began publishing the ASA Relative Value Guide (RVG) in 1962. The ASA, through its Committee on Economics, continues to publish an annual update to this document. As a member of that committee since 1997 and currently its chair, this author has been actively involved in the preparation of this guide for a number of years.

The RVG evolved fairly rapidly, but the ASA received a legal challenge from the U.S. Federal Trade Commission, which claimed that the publication of relative values promoted illegal price fixing. The ASA prevailed in court in 1979. Ironically, the 1989 Relative Value Guide became the basis for Medicare’s anesthesia payment system, which we will discuss in a later chapter.

The ASA Newsletter published a brief but excellent history of the Relative Value Guide in 2004. You can download it from www.asahq.org/Newsletters/2004/09_04/ogunnaike.html.

The American Medical Association Current Procedural Terminology (CPT)¹ (Current Procedural Terminology © 2006 American Medical Association.® All Rights Reserved. Applies to all CPT code references in this chapter) organizes the codes describing anesthesia care primarily by body region, with each code encompassing one or more surgical procedures. Some anesthesia services are not easily categorized by body system, leading to special sections for radiologic, burn, obstetric, and miscellaneous other services.

In some cases a single anesthesia code can cover hundreds of surgical procedures. When we discuss coding resources later on, you will learn about the ASA Crosswalk publication, which provides a systematic association between every diagnostic or therapeutic CPT procedure that may require anesthesia and one or more anesthesia services.

Each anesthesia code has an associated base unit value. CPT does not publish the relative values; however, the ASA Relative Value Guide does. An underlying principle of the anesthesia relative value system is that all procedures having the same base value and anesthesia time are equivalent in work. For example, anesthesia for an open reduction and internal fixation of a proximal femur fracture taking 90 minutes is equivalent to anesthesia for hysterectomy also lasting 90 minutes, because both anesthesia services have 6 base units assigned. We will discuss methods for calculating anesthesia payments in Chapter 209.

Anesthesia services have their own section in CPT, and the range of anesthesia code numbers is 00100 to 01999. CPT lists approximately 270 anesthesia services. As one progresses through each anesthesia section, the hundreds digits is incremented by one. For example, the code family for spine and spinal cord anesthesia procedures fall in the code range 00600 to 00699. The next section in CPT, “upper abdomen,” covers the codes 00700 to 00799. Not every code number in the anesthesia section has a code assigned, allowing room for future growth in the code set.

Here are a few examples of anesthesia codes:

As you may have noticed, the codes have a specific structure as described in this meta-description:

Although most anesthesia codes stand alone, CPT does include a few “add-on” codes that are reported with other services. For example, the procedure codes describing burns include add-on codes to describe large-surfacearea burns. Also, when a caesarean section is done after placement of a labor epidural, one would report CPT code 01967, describing neuraxial analgesia for labor, as well as add-on code 01968, describing caesarean section following neuraxial labor analgesia.

A key point for any procedural coding, including anesthesia services, is that the code selected must be the one that most specifically describes the service. To learn more about finding the best fit between the surgical procedure and the anesthesia service, see the discussion of the ASA Crosswalk in Chapter 211.

The following sections will investigate major coding issues that anesthesiologists commonly face. These areas include evaluation and management services, acute and chronic pain procedures, and invasive line and monitoring procedures. During this review, I will try to provide enough background information and specific guidance to help you code correctly. In some cases, I will refer you to primary sources for additional information for topics that are sufficiently complex to preclude an accurate and succinct presentation in this book.

Evaluation and management (E/M) services are the most frequently reported type of medical service, comprising more than 40% of all Medicare physician payments. Office visits, consults, critical care management, emergency medicine evaluations, and numerous other services are all part of the larger evaluation and management family. Although the anesthesiologist who works primarily in the operating room does not perform nearly as many reportable E/M encounters as does his medical and surgical colleagues, understanding E/M is still very important. In 2004, about 7% (˜$114 million) of all Medicare payments to anesthesiologists were for E/M services. For two anesthesiology subspecialty areas, pain and critical care medicine, E/M comprises a significantly larger share of total revenue.

This section discusses visits, consults, and critical care services. I will not discuss other E/M services, which are rarely performed by anesthesiologists,
such as nursing home visits, preventive medicine services, and care plan oversight.

Visits and consults have various levels of service. These levels reflect the time and work involved in caring for the patient. The key service elements involved in E/M include the history, physical examination, and medical decision making. In some situations, counseling and coordination of care may dominate. In these cases, the total time spent in counseling and coordination determine the appropriate E/M code to report. Other characteristics that help determine which E/M codes to report include the site of service (office or facility) and whether the patient is new to the practice or previously seen. Both site of care and prior patient contact often affect payment level.

As with many elements of the payment system, a seemingly simple question such as “Is this a new patient?” has a nuanced and complex answer. According to CPT, a new patient is “one who has not received any professional services from the physician, or another physician of the same specialty who belongs to the same group practice, within the past 3 years.” Medicare, for once, has a slightly less restrictive approach. For Medicare patients, the CPT definition applies except that Medicare limits the definition of “professional services” only to E/M services.

This difference is important to anesthesiologists. For example, a surgeon sends a Medicare patient to your pain clinic for evaluation and treatment of radicular pain affecting the back and left leg. Assume that one of your partners provided anesthesia to this patient for a cholecystectomy 12 months earlier, and further assume that both you and your partner have listed your specialty with Medicare as “anesthesiologist.” Because this is a Medicare patient, the previous anesthesia care, not being an E/M service, would make the pain management evaluation a new patient service; conversely, by the CPT definition applied by most other payers, this hypothetical E/M service would be for an established patient. Also, if your specialty designator is “pain medicine” or “interventional pain medicine” and your partner’s is “anesthesiologist,” then by either definition, you practice a different specialty than your partner, making this a new patient encounter no matter the payer (but please note the important change in CPT definition beginning in 2007 described below). One final point to make the answer to this “simple” question complete: The requirement for being in the same “group practice” is that if the practice bills for both you and your partner using the same Federal tax ID number, then you are in a group practice with the other physician. My former employer has practice sites throughout Oregon, all operating under the same tax ID number. So if I performed an E/M service on a patient in Corvallis, Oregon, that another anesthesiologist in the group cared for 90 miles away in Portland within the previous 3 years, then CPT would consider this patient to be an established patient. It is important to note that
as of 2007, CPT changed the definition of new versus established patient to indicate that “same specialty” means “same specialty or same sub-specialty,” provided the tax ID number for both providers is the same. I do not know whether the Medicare definition will change to match the CPT definition.

The level of service within a family of E/M codes can depend either on the complexity of the key service elements or, when counseling and coordination of care are the dominant activities, on the total time spent with the patient. Because determining the correct level of service has proven somewhat difficult and Medicare and other payers were suspicious of “up-coding” of services, CMS has published documentation guidelines to help assure that physicians code E/M services correctly. These guidelines, last updated in 1997, are available at www.cms.hhs.gov/MLNEdWebGuide/25_EMDOC.asp.

Correctly determining a level of service using these documentation guidelines is fairly complex. The guidelines categorize each element and subelement of service into a hierarchy that, taken as a whole, allows for determining the correct level of service. Rather than repeating these verbatim or alternatively oversimplifying the guidelines so much that the reader may, by using the simplified description, determine the level of service incorrectly, I urge every anesthesiologist to read the guidelines and have them available as a resource when coding evaluation and management encounters. Another excellent source of general information and overview of all the E/M services is the introduction to the E/M section in each year’s CPT publication. I also strongly encourage you to consult with a certified medical coder with recent experience in E/M coding periodically, to confirm that your assignment of level matches both current best practices and the information in the medical record. E/M services are an ongoing area of review by government investigators and private insurers, as these services are both high in volume and have the potential for fraudulent or abusive billing. Caveat venditor—“Let the seller beware.”

A number of useful articles written by Karin Bierstein, J.D., M.P.H., who serves as the ASA’s Associate Director of Professional Affairs, pertain to the use of E/M codes by anesthesiologists. These are available at the ASA web site: