Revenue Cycle Insider

Anesthesia Coding:

Know Limitations of G8 Modifier

Question: Can I apply modifier G8 for any procedure for a Medicare beneficiary if the documentation says the procedure is complicated and invasive?

Arizona Subscriber

Answer: No. According to the Centers for Medicare & Medicaid Services (CMS), modifier G8 (Monitored anesthesia care (mac) for deep complex, complicated, or markedly invasive surgical procedure) is only appropriate for certain procedures.

Surgical team with anesthesia mask. Team of surgeons leaning over patient with anesthesia mask ready.

Other payers’ policies may vary, but according to local coverage determination (LCD) A57361, “Anesthesia procedures listed in … this article are examples of those that are usually provided by the attending surgeon and are included in the global fee and are not separately billable. In certain instances, however, MAC [monitored anesthesia care] provided by anesthesia personnel may be necessary for these procedures if the patient has one or more of the conditions or situations ….” (See the article for specifics.)

In some of these situations, the LCD says modifier G8 should be appended when the respective procedure CPT® code is not fully descriptive, but only for certain anesthesia codes, including:

  • 00100 (Anesthesia for procedures on salivary glands, including biopsy)
  • 00300 (Anesthesia for all procedures on the integumentary system, muscles and nerves of head, neck, and posterior trunk, not otherwise specified)
  • 00400 (Anesthesia for procedures on the integumentary system on the extremities, anterior trunk and perineum; not otherwise specified)
  • 00160 (Anesthesia for procedures on nose and accessory sinuses; not otherwise specified)
  • 00532 (Anesthesia for access to central venous circulation)
  • 00920 (Anesthesia for procedures on male genitalia (including open urethral procedures); not otherwise specified)

The LCD says that documentation must list special conditions/criteria leading to the use of MAC, and diagnoses also must support the MAC being medically necessary.

Rachel Dorrell, MA, MS, CPC-A, CPPM, Production Editor, AAPC

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