Anesthesia start and stop times are a key determinant to case reimbursement. For sites still on paper, a billing compliance risk exists when providers round to the nearest 5-minute increment, instead of charting to the exact minute. This article is intended to discuss this documentation phenomenon, and to provide strategies to mitigate future risk.
First, let’s start at the beginning. Anesthesia is reimbursed by insurance plans using a formula of “base + time, x conversion factor”. The base units represent the complexity of the surgical procedure(s) performed and are assigned by the ASA and CMS. These values are mainly the same for both organizations, with some minor differences. Time is the aggregate number of minutes that the anesthesia provider(s) spend on clinical activities with the patient, typically beginning in pre-op and extending through anesthesia care transfer in PACU. The conversion factor is a group’s “fee per unit” rate, which is either negotiated or pre-assigned by the insurance plan.
The issue of time rounding applies to carriers like Medicare, who pay on fractionalized units. Each 15 minutes of anesthesia time equals one full time unit, with each remaining time interval (less than 15 minutes) assigned a fraction. For example, anesthesia for a colonoscopy case that started at 7:57 and ended at 8:38 would be billed as 2.73 time units. When the provider rounds the start time to 7:55 and the end time to 8:40, the new time unit value is 3.0 time units, resulting in an overpayment of about $6 to Medicare. Although this may not seem like a lot, it can add up when multiple members of your practice are routinely documenting in this fashion. Simply put, it’s not a risk that any group should ignore, as the False Claims Act can impose fines of up to $11,000/claim.
For anesthesia practices currently on electronic medical records, this is typically not an issue, as network time is used for charting purposes. However, providers working at paper sites often select the nearest 5-minute increment to document their anesthesia times. There is likely no nefarious intent involved, but rather, a lack of understanding of how some insurance plans pay for their clinical services.
As the old saying goes, you can’t manage what you don’t measure. Since most groups have no idea who within their practice may be charting times incorrectly, it’s paramount that your billing company provide you with a report that shows the percentage of cases billed (by provider and service location) with start or stop times ending in “0” or “5”, which will help to quickly identify practitioners in need of education. The law of large numbers says that times ending in “0” or “5” should be approximately 20% of a provider’s total case volume. More than likely, you’ll see some outliers, once you have the appropriate tools to assess. MSN Healthcare Solutions will be happy to provide you with such a sample report, upon request.
Hal has 30+ years of experience on both the payor and RCM side, with a focus in Anesthesia. He formerly worked as a senior claims approver at United Healthcare, as well as a compliance officer for multiple national anesthesia billing companies. His broad-based experience ensures that MSN clients have a resource for documentation and billing issues. His past speaking engagements include ASA, MGMA, Dartmouth, and Johns Hopkins.


