Anaesthesia items

Rules about billing Medicare Benefits Schedule (MBS) items for anaesthesia services and how to apply them.

Read the relevant item descriptions, fact sheets and explanatory notes on the MBS Online website.

Relative Value Guide

We calculate Medicare benefits for anaesthesia services using the Relative Value Guide (RVG). The RVG groups anaesthesia services within anatomical regions.

Anaesthetic services are in Group T.10 under Category 3 Therapeutic Procedures of the MBS.

We calculate Medicare benefits for anaesthesia services using the Relative Value Guide (RVG). The RVG is based on an anaesthesia unit system. It reflects the complexity and time taken for the service.

You can choose different items for the relative value of an anaesthetic service.

Under the RVG, the MBS fee for anaesthesia in connection with a procedure is comprised of up to 3 components:

  1. basic unit.
  2. time unit.
  3. modifying unit.

Basic unit

The basic unit value represents the degree of difficulty for the procedure. We call this the anatomical item. You can choose one item from:

  • MBS Subgroups 1-18
  • MBS Subgroup 20
  • perfusion item 22060 in MBS Subgroup 19.

Time unit

The time unit value is based on the total time of the anaesthetic. You can choose one item from MBS Subgroup 21.

Modifying unit

Modifying units recognise added complexities. You can choose items from MBS Subgroups 22-25 where applicable.

Therapeutic and diagnostic items are for extra services with anaesthesia. You can choose items from MBS Subgroup 19 where applicable but not item 22060.

Read more about the RVG for anaesthetics in explanatory notes on the MBS. Medicare Benefits Schedule - Note TN.10.1 to TN.10.30.

Billing guidelines

When billing an episode of anaesthesia you must bill both:

  • a basic unit value
  • a time unit value.

You must record the start and end times in the patient notes.

You can also bill any of these extra items:

  • physical status modifier
  • age modifier
  • emergency modifier.

Ordering services

You must submit anaesthetic items in a specific order. We’ll reject claims submitted out of order.

The order is as follows:

  1. Basic unit value where more than one appears on an invoice or receipt. They should all be listed above the time value unit. Medicare benefit will only be payable for one Basic unit value.
  2. One time unit value.
  3. Physical status modifier, where applicable.
  4. Age modifier, where applicable.
  5. ‘In hours’ emergency modifier, where applicable.
  6. Therapeutic and diagnostic services, where applicable.
  7. Emergency after hours modifier, where applicable.

Read more about billing for anaesthesia MBS items on the Health Professionals Education Resources (HPE) website.

Service limits

We pay a Medicare benefit for any of the following:

  • anaesthesia provided for an eligible procedure that includes the annotation ‘Anaes’ in the MBS item description
  • items for one professional capacity, as either the anaesthetist, assistant anaesthetist, perfusionist or the practitioner performing the procedure
  • a basic unit item when it’s billed with one time unit item
  • one basic unit item - if more than one applies, choose the item with the highest value
  • one physical status modifier item - if more than one applies, choose the item with the highest value.

Perfusion services

You can bill items 22055 and 22075 on their own or within an RVG episode.

After-hours modifiers

You can only bill after-hours emergency modifiers when more than 50% of the time for emergency anaesthesia is either:

  • between 8 pm to 8 am on any week day
  • any time on a Saturday, Sunday or a public holiday.

You can’t bill both the emergency modifier and the after-hours emergency modifier for the same episode.

The after-hours emergency modifier is a fee loading item. You must include all components of the episode together when billing this item. This helps us calculate the correct benefit.

Some electronic claiming channels limit the number of items you can transmit together. This means you may need to either bill:

  • attendance items separately
  • items not associated with the episode of anaesthesia, such as regional field nerve blocks, separately.

If the number of items still exceeds the limit, you’ll need to issue a manual account or claim.

Giving us more billing information

In some cases, we may ask you to give us more information on your account or claim.

If you’re the anaesthetist, we need to know the medical practitioner’s name who performed the eligible procedure.

If you’re the assistant anaesthetist, we need the name of both:

  • the medical practitioner who performed the eligible procedure
  • the principal anaesthetist.

If you bill the after-hours emergency modifier, we need to know all the following:

  • the service start time
  • the service end time
  • the total time taken.

If you bill an attendance on the same date as the anaesthetic, other than the pre-anaesthesia examination, we need to know either:

  • the time of the attendance item
  • confirmation that the attendance took place on a separate occasion.

If you bill pre- or post-operative services not part of the episode of anaesthesia, please note that the service took place on a separate occasion. For example, item 18222 infusion of a therapeutic substance to maintain anaesthesia or analgesia.

If you bill a re-submitted or amended account, we need these details clearly identified on the account.

If you bill item 22012 or 22014, we need to know the type of pressure being monitored.

If you bill item 21990, we need to know the surgical item or abandoned items. Read more about billing abandoned or discontinued surgery.

Billing patients privately

When you issue an itemised account or receipt to your patient, we recommend a separate charge for each of the following:

  • the pre-anaesthesia attendance
  • the item or items representing each unit component of the anaesthetic service
  • any separate attendance or attendances
  • any regional or field nerve blocks not associated with the episode of anaesthesia.

If you combine charges on an account, we’ll allocate an amount against each item.

If we cannot allocate amounts, we’ll ask for a revised account with individual charges.

Common billing errors

You can resubmit a corrected claim if we reject an entire claim in the first instance.

Except for item 22060, you don’t need to resubmit the whole RVG episode if you missed:

  • attendance items
  • therapeutic or diagnostic services.

You can make a separate claim for these items.

An exception is where both:

  • therapeutic or diagnostic services are missed
  • the after-hours emergency modifier applies to the episode.

This is because the therapeutic and diagnostic items are included in the modifier’s derived fee calculation.

If you include consult items for pre- or post-anaesthesia services in the same claim as RVG items, make sure they’re before or after all RVG items.

You can send an adjustment request when either:

  • a Medicare benefit was paid for an incorrect item
  • you missed a modifier item.

To do this, use the following forms:

Page last updated: 20 March 2025.
QC 74113