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How Is Anesthesia Time Calculated for Coding and Billing?

March 24, 2023

Anesthesia medical billing and coding rely on accurate documentation of services, including reporting time units. Failing to calculate time properly can result in denied or rejected claims, which impacts your facility’s revenue.

Below, we explain how to calculate anesthesia time units and break down their integral role in billing and coding.

Understanding the Basics of Anesthesia Coding

Anesthesia coding involves many complexities that make it more challenging than other specialties. In addition to determining the CPT code of the surgery performed and differentiating between medical direction vs. medical supervision, recording anesthesia time units is another crucial component of billing and coding.  

One unique feature of anesthesia coding is how providers calculate charges. Correctly reporting and coding charges involves the following criteria:

  • The difficulty of the procedure performed
  • Time
  • Modifying factors (e.g., patient’s health)

The general formula for calculating anesthesia charges is:

(Base units + Time units + Modifying units) x Conversion factor = Anesthesia charge

  • Base Units – every anesthesia procedure has an assigned code with a corresponding base unit value. The more complex the procedure is, the higher the base unit. 
  • Time Units – one unit of time is recorded for each 15-minute increment of anesthesia time. (e.g., a 45-minute procedure incurs three units of anesthesia time)
  • Modifying Units – emergencies and the patient’s changing health conditions are considered modifying units in anesthesia. 
  • Conversion factor – this number refers to the cost assigned to each unit and is specific to the provider’s location.

The Importance of Accurate Anesthesia Time Calculation for Coding and Billing

Understanding how to calculate anesthesia time can minimize compliance issues.

Too often, CRNAs and anesthesiologists need a clearer understanding of reporting time units. For example, when anesthesia time starts and ends. According to the CPT guidelines, anesthesia time begins when the provider or anesthesiologist begins to prepare the patient for anesthesia services in the operating room or similar area and ends when the provider is no longer attending to the patient who is already under postoperative care.

Failure to correctly report time units can result in overbilling, leaving your facility vulnerable to compliance actions or underbilling, which can lead to revenue loss.

As commercial payers and the government become more meticulous about improper provider billing and coding, anesthesia facilities can expect facing audits and investigations of their coding and claims procedures. Accurate anesthesia time calculation and adherence to the correct formula for charges are vital to ensuring compliance and successful reimbursements.

coronis health anesthesiologist administering mask

Anesthesia Time Calculation for Multiple Procedures

When multiple procedures are performed simultaneously under the same anesthesia, you must code the procedure with the highest base value (or the most complex one) and add the total time for all procedures during the same encounter. 

How Anesthesia Time Affects Reimbursement and Payment for Services

coronis health anesthesia medical worker checking patient's heartrate

Any claim submitted for reimbursement must indicate what procedure was performed and why it was done. To properly report anesthesia services, billers, and coders must adhere to the rules and guidelines specific to anesthesia care, including an accurate calculation of time units. 

Faster reimbursement and payment for services, smooth revenue cycle, and consistent audits result from following the appropriate formula for calculating time and anesthesia charges and using the correct codes. 

Anesthesia Time and Billing: Tips and Best Practices

Accurate documentation is critical to achieving anesthesia billing compliance and faster reimbursements. Here are billing tips on how to maintain compliance and prevent revenue loss.

  • Report the correct codes – CPT codes provide information about a procedure, how it was performed, and why it was performed to establish medical necessity.
  • Know your modifiers – these refer to the two-character indicators that identify relevant details on a claim.
  • Append physical status modifiers – these are used to report on the patient’s overall physical health at the time of the procedure. 
  • Report qualifying circumstances – these indicate the conditions that impact the nature of the anesthetic service performed.
  • Calculate and report time accurately – calculate base and time units for anesthesia and properly document the anesthesia start and stop times. Strictly adhere to the rules and formulas provided by CMS And commercial insurance companies to remain compliant.

Questions About Anesthesia Billing and Coding? Contact Coronis Health Today!

Part of successful anesthesia coding and billing is partnering with a team of experienced and highly trained professionals. Outsourcing your anesthesia medical billing may be what your facility needs to improve compliance, streamline your billing process, and boost your cash flow. 

Coronis Health is a global revenue cycle management company with decades of experience offering specialized solutions to healthcare practices and facilities. By combining industry-leading technology with high-touch relationship building, Coronis Health can help optimize your medical billing and revenue cycle management. 

To learn more about how your facility can benefit from our anesthesia medical billing services, request your free financial checkup today.

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