Official Medical Fee Schedule (OMFS)
Physician Services Fee Schedule

§ 9789.18.1 Payment for Anesthesia Services - General Payment Rule

Last update
August 8, 2022


Calculating OMFS reimbursement for Anesthesia Services is a complex process that involves multiple tables and formulas.

To calculate the Base Maximum Fee for Anesthesia services, use these factors:

  • Base Units
  • Time Units
  • Anesthesia Conversion Factor
  • Statewide GAFs for Anesthesia

To determine these factors and calculate payment for anesthesia services, follow the instructions below.

Step 1. Determine Anesthesia Base Units

First, download the file titled 2014 Anesthesia Base Units by CPT Code [ZIP, 13KB] in the Anesthesiologists Center on the Medicare website. The anesthesia base units are unchanged for 2016.

Step 2. Determine Time Units

To determine Time Units, see Section 9789.18.8.

Time Units are calculated by dividing the actual reported anesthesia time by 15 minutes.

Anesthesia - Time and Calculation of Anesthesia Time Units

Step 3. Determine the Anesthesia Conversion Factor

The Anesthesia Conversion Factor (CF) is $28.8003, located in § 9789.19, the Update Table.

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Step 4. Determine the Statewide GAF for Anesthesia

The Statewide GAF for Anesthesia is 1.0313, located in § 9789.19, the Update Table on page 59.

Step 5. Calculate Base Maximum Fee

To calculate the Base Maximum Fee for anesthesia services, use the following equation:

[Base Unit + Time Unit] * CF * Statewide Anesthesia GAF = Base Maximum Fee

Because these factors frequently change, be sure to check the California fee schedule regulations often.

California Code of Regulations (CCR)

§ 9789.18.1 Payment for Anesthesia Services - General Payment Rule

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Official Medical Fee Schedule

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