Calculating and Coding for Anesthesia Time
How to calculate and report anesthesia time properly depends on the payer. For payers that follow CPT® rules, report time per 15 minute intervals. At least half this time (7.5 minutes) must pass to report a unit. For example:
30 minutes of anesthesia = two units (30=15+15)
38 minutes of anesthesia = three units (38=15+15+8)
37 minutes of anesthesia = two units (37=15+15+7)
Medicare providers follow Centers for Medicare & Medicaid Services guidelines, found in the Internet Only Manual, Claims Processing Manual 100-04 Chapter 12:
G. Anesthesia Time … is defined as the period during which an anesthesia practitioner is present with the patient. It starts when the anesthesia practitioner begins to prepare the patient for anesthesia services in the operating room or an equivalent area and ends when the anesthesia practitioner is no longer furnishing anesthesia services to the patient, that is, when the patient may be placed safely under postoperative care. Anesthesia time is a continuous time period from the start of anesthesia to the end of an anesthesia service. In counting anesthesia time for services furnished on or after January 1, 2000, the anesthesia practitioner can add blocks of time around an interruption in anesthesia time as long as the anesthesia practitioner is furnishing continuous anesthesia care within the time periods around the interruption.
Actual anesthesia time in minutes is reported on the claim. For anesthesia services furnished on or after January 1, 1994, the A/B MAC computes time units by dividing reported anesthesia time by 15 minutes. Round the time unit to one decimal place. The A/B MAC does not recognize time units for CPT codes 01995 or 01996.
For purposes of this section, anesthesia practitioner means a physician who performs the anesthesia service alone, a CRNA who is not medically directed, or a CRNA or AA, who is medically directed. The physician who medically directs the CRNA or AA would ordinarily report the same time as the CRNA or AA reports for the CRNA service.