Part B Insider (Multispecialty) Coding Alert

Add-on Codes:

Know the 3 Types of Medicare Add-on Codes

CCI pays attention to the add-on tables. Shouldn’t you?

CPT® doesn’t designate primary codes for every add-on code, but CMS offers a few clues about when you should report specific add-ons in Transmittal 2636, Change Request 7501, effective April 1, 2013.

Background: An add-on code reports a service that is "always performed in conjunction with another primary service. An add-on code is eligible for payment only if it is reported with an appropriate primary procedure performed by the same practitioner. An add-on code is never eligible for payment if it is the only procedure reported by a practitioner," states the Transmittal. "Rarely contractors may allow with appropriate submitted documentation, either pre-pay or on appeal, payment for a primary code and add-on code on two consecutive dates of service if the services are appropriately related."

For additional information, The CPT® definition of add-on codes can be found in the Introduction section of the CPT® Manual and a complete list of add-on codes is found in Appendix D.

Tackle the Tables to Improve Coding Compliance

The latest CMS Transmittal provides three different tables denoting add-on codes and how to use them. Each add-on code is placed in a table based on whether CPT® provides an exhaustive list of primary codes, a partial list of primary codes, or no defined primary codes.

Type I: The Type I add-on codes in the first table are paired with the primary codes identified by the CPT® manual. Medicare will not pay a Type I add-on code unless one of the listed primary codes is also reported. The exception is +99292 (Critical care each additional 30 minutes …). A second physician may report +99292 without 99291 (Critical care … first 30-74 minutes) "if another physician of the same specialty in his group practice is paid for CPT® code 99291 on the same date of service," the Transmittal states.

Type II: Type II add-on codes are those that have no primary codes listed by CPT®. "Claims processing contractors are encouraged to develop their own lists of primary procedure codes for this type of add-on codes," the Transmittal states.

CMS posts non-exhaustive lists of possible primary codes for some, but not all, of the Type II codes. For example, the table includes this pairing based on ACR/SIR recommendations:

Add-on:

+37250, Intravascular ultrasound (non-coronary vessel) during diagnostic evaluation and/or therapeutic intervention; initial vessel (List separately in addition to code for primary procedure)

Primary possibilities:

34800-34805, Endovascular repair of infrarenal abdominal aortic aneurysm or dissection

34900, Endovascular repair of iliac artery

35471, 35472, 35476, Transluminal balloon angioplasty, percutaneous

61624, 61626, Transcatheter permanent occlusion or embolization

Type III: For the add-on codes labeled as Type III codes, CPT® lists some but not all primary code possibilities. In addition to the CPT®-designated possible codes, CMS encourages contractors to create their own lists of appropriate primary codes.

Resource: You can check Medicare’s pairings of primary and add-on codes at www.cms.gov/Regulations-and-Guidance/Guidance/Transmittals/Downloads/R2636CP.pdf. Additionally, the most recent version of the Correct Coding Initiative (CCI) manual adds a section about the tables. The language is similar to the Transmittal regarding the required use of proper primary codes for payment and contractors creating lists of appropriate primary codes for Type II and Type III codes. You can download the manual from the Downloads section of www.cms.gov/Medicare/Coding/NationalCorrectCodInitEd/.