How anesthesiologist fees are calculated

The calculation of anesthesiologist fees follows a logic structured by the Brazilian Hierarchical Classification of Medical Procedures (CBHPM), published by the Brazilian Medical Association (AMB). The current edition is the 2022 one, and the reference values are updated annually by an official notice from the AMB, based on the INPC/IBGE inflation index for the period.

Understanding this calculation is essential for billing specialists and hospital managers: errors in identifying the anesthesia tier or in applying the reference values are one of the most common causes of denials in surgical claims.

What anesthesia tier is

Anesthesia tier is the classification that defines the complexity of the anesthetic act in each surgical procedure. In the CBHPM, this scale runs from 0 to 8, and each level corresponds to a degree of risk, duration and technical complexity.

Each anesthesia tier (from 0 to 8) corresponds to a procedure tier in the CBHPM table, expressed in reais. This correspondence is defined in the CBHPM general instructions and is the starting point for calculating the fee.

How the correspondence between anesthesia tier and CBHPM tier works

Anesthetic acts do not follow the procedure tier scale (1A to 14C) directly. They have their own correspondence, defined in the CBHPM general instructions, as shown in the table below:

The value in reais of each CBHPM tier is updated annually by the AMB Official Notice. As of October 2025, the reference value of the UCO (Operating Cost Unit) was set at R$ 29.80, according to the notice published on October 18, 2025. The monetary value of each tier should be checked directly in the current notice, available on the AMB website.

Practical example: calculating the fee for an osteotomy

To illustrate the calculation, let’s use an osteotomy as an example.

Step 1 — Identify the procedure’s anesthesia tier

In the CBHPM table, each surgical procedure indicates its anesthesia tier. For an osteotomy, the anesthesia tier indicated is 6.

Step 2 — Find the corresponding CBHPM tier

Checking the correspondence table in the general instructions, anesthesia tier 6 corresponds to CBHPM tier 9B.

Step 3 — Look up the value of tier 9B in reais

The monetary value of tier 9B is in the current CBHPM Official Notice, available on the AMB website. This value is updated annually and should be checked before each billing cycle to make sure the fee is being calculated on the basis of the correct table.

Step 4 — Apply the payer’s contractual factor

The CBHPM reference value is the floor for the calculation. The amount actually paid by the payer depends on the percentage negotiated in the contract (which can vary between payers and between the editions of the table adopted in each contract). Always check which CBHPM edition and which coverage percentage are set out in the contract with each health plan.

Add-ons that may apply to the base fee

The amount calculated from the anesthesia tier is the base fee. The CBHPM provides for add-ons in specific situations, which must be properly documented to avoid denials:

Each add-on requires proper recording on the anesthesia record. Add-ons without supporting documentation are one of the main causes of denials in anesthesia fees. To understand how to apply add-on factors in billing, see the article How to fill in the reduction or add‑on factor.

Anesthesiologist fees and the hospital revenue cycle

Calculating the anesthesia fee correctly is only one part of the process. For the amount to reach the hospital without a denial:

• the tier identified in billing must match exactly what is recorded in the medical record;

• the surgical procedure code must be correct;

• the CBHPM edition applied must be the one set out in the contract with the payer.

Any of these inconsistencies can result in a denial, and denials in surgical claims usually involve substantial amounts. As part of a well-structured hospital billing process, auditing surgical claims before submission is the most efficient way to avoid these losses.

Frequently asked questions about anesthesia tier

What is anesthesia tier in the CBHPM?

It is the classification that defines the complexity of the anesthetic act in each surgical procedure, on a scale of 0 to 8. Each level corresponds to a procedure tier in the CBHPM table, which determines the reference value of the anesthesiologist’s fee.

How do you calculate the anesthesiologist’s fee using the CBHPM?

Identify the procedure’s anesthesia tier in the CBHPM table, find the corresponding procedure tier in the general instructions, look up the value in reais in the current AMB Official Notice and apply the contractual percentage negotiated with the payer.

Are CBHPM values fixed?

The reference values are updated annually by the AMB through an Official Notice, based on the INPC/IBGE index for the period. The amount actually paid by payers depends on the percentage and the CBHPM edition set out in each contract.

Which add-ons can be applied to the anesthesia fee?

The CBHPM provides for add-ons for special hours (nights, holidays and weekends), additional surgery time, the patient’s age group and high anesthetic risk. All of them require proper documentation on the anesthesia record to avoid denials.

Where can I find the updated CBHPM values?

On the official website of the Brazilian Medical Association (AMB): https://amb.org.br/cbhpm/, where the annual notices with the current tier and UCO values are published.