Prior Authorization

About PA RSNAT Model

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About PA RSNAT Model

The Centers for Medicare & Medicaid Services implemented a prior authorization model for repetitive scheduled non-emergent ambulance transport to determine whether prior authorization helps reduce expenditures while maintaining and/or improving quality of care.

The RSNAT prior authorization model applies to ambulance suppliers who provide Part B Medicare covered ambulance services and are enrolled as independent ambulance suppliers. Institutional (hospital) based ambulance services are excluded from the model.

It is important to note, prior authorization does not create any new documentation requirements. Rather, it requires the same information necessary to support Medicare payment, only earlier in the process. Prior authorization allows ambulance suppliers to address issues with a claim prior to rendering a service and submitting it for payment. This will help ensure that all relevant Medicare guidelines are met prior to the service being rendered and before the claim is submitted for processing. This process will also help reduce denials and the subsequent appeals process.

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CMS started this process with ambulance suppliers in South Carolina, New Jersey, and Pennsylvania on 12/1/2014, for transports occurring on or after 12/15/2014. The following year, ambulance suppliers in Delaware, the District of Columbia, Maryland, North Carolina, Virginia and West Virginia began submitting prior authorization requests on 12/15/2015 for transports occurring on or after 1/1/2016.

CMS is now expanding the model to the rest of the U.S. and its territories. By August 2022, all U.S. states and territories will be using the RNSAT prior authorization model.

  • Jurisdiction 6 (Illinois, Minnesota, Wisconsin) implemented April 2022
  • Jurisdiction K (Connecticut, Maine, Massachusetts, New Hampshire, New York, Rhode Island, Vermont) implemented June 2022

Upon implementation, ambulance suppliers must complete the prior authorization process for RSNAT prior to submitting their claims. If they do not receive an affirmed prior authorization, claims will be subject to prepayment review.

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How it Works

The ordering physician/practitioner is required to supply either the ambulance supplier or beneficiary, with a physician certification statement (see 42 CFR Section 410.40(a)) as well as any other relevant documentation that supports medical necessity for the RSNAT. The prerequisite to submit this documentation is part of a provider’s compliance in the Medicare program.

If the ordering physician/practitioner does not supply the certification statement and additional required documentation, the ambulance supplier may forward the informational letter created by CMS. This letter reminds the ordering provider of their responsibility to provide the physician certification statement and other applicable documentation.

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Ambulance HCPCS Codes

The following ambulance HCPCS codes are subject to prior authorization:

  • A0426 — Ambulance service, Advanced Life Support (ALS), nonemergency transport, Level 1
  • A0428 — Ambulance service, Basic Life Support (BLS), nonemergency transport

Prior authorization is not required for the mileage code, A0425, as it is considered an associated code. The mileage code should be billed on the same claim as the transport code (A0426 or A0428).

Revised 11/30/2022