Capturing Medical Necessity in Ambulance Coding

By AGS Health

March 26, 2024

Recognizing and establishing medical necessity when billing ambulance and emergency medical services is critical for the financial health of ambulance operators – also to effectively educate service providers on how to accurately capture appropriate clinical language in their charts.

As detailed in Medical Necessity in Ambulance Coding, a guide that serves as a resource for ambulance service providers and coding professionals to understand and apply medical necessity guidelines, accurate charting, and coding also help maintain compliance with regulatory requirements, avoid audits, and prevent potential penalties.

Defining Medical Necessity

“Medical necessity” in ambulance coding refers to the justification for providing ambulance services based on a patient’s medical condition. It ensures that ambulance services are used appropriately, only when other means of transportation are contraindicated, and when the patient's medical condition warrants immediate transportation to a healthcare facility.

Criteria for establishing medical necessity often include factors such as the patient's medical condition, the presence of life-threatening symptoms, the potential for deterioration during transportation, and the availability of alternative means of transportation. Clinical language in the ambulance call record/report (ACR) must substantiate that the patient’s condition required an ambulance for transport and that any other means of transport could have jeopardized the patient’s health, which the law refers to as “contraindicated.”

CMS Guidelines

Understanding the specific guidelines that Medicare and Medicaid have in place for determining medical necessity, defined in Title XVIII of the Social Security Act (the Act) in §1861(s)(7), is crucial for proper coding, billing, and reimbursement of ambulance services.

Importantly, medical necessity is not a limitation of liability situation, but rather a coverage issue defined in the patient’s Medicare & You Handbook. Terms such as “bedridden,” “bed-confined,” “stretcher patient,” or “required restraints” do not, by themselves, support medical necessity.

Nor is the term “bed-confined” synonymous with “bed rest” or “non-ambulatory.” It is simply one element of the beneficiary's condition to consider in determining medical necessity. The contractor’s determination will always use “contraindicated” for the medical necessity of ambulance transport.

The Centers for Medicare and Medicaid Services (CMS) indicates a beneficiary is bed-confined if he/she is:

  • Unable to get up from bed without assistance
  • Unable to ambulate, and
  • Unable to sit in a chair or wheelchair

Situations Medicare may consider bed-confined include:

  • Muscle contractures and stiffing symptoms creating non-ambulatory status in a patient who cannot sit
  • Severe generalized weakness
  • Immobility of lower extremities issues causing a patient to be unsafe sitting in a wheelchair,or
  • Patient in spica cast, fixed hip joints, or lower extremity paralysis

CPT codes are used to categorize ambulance services based on factors like transport mileage, level of care, and type of ambulance used. Modifiers are used to indicate specific circumstances, such as prolonged transport, multiple patients, or specialized equipment used during transportation. ICD-10 codes are used to justify ambulance transportation based on the patient's medical condition or diagnosis.

Emergent vs Non-Emergent Transportation

Emergent vs Non Emergent Transportation

The process of establishing medical necessity varies to a small degree subject to the priority level of the transport in question—emergent and non-emergent—although most documentation requirements remain standard regardless.

Emergency: Ambulance response typically with lights and sirens to the scene of an emergency for the purpose of rendering emergency medical services and/or providing transportation of the sick and injured to a hospital or other place for medical attention. Certain presenting conditions when the patient is picked up establish medical necessity, including:

  • Syncope/collapse
  • Neurological disorders such as seizures
  • Respiratory and cardiovascular distress
  • Acute trauma such as injuries resulting from a motor vehicle accident or crime
  • Pregnancy and labor complications
Typical medical necessity evaluation criteria for emergent transports
Criteria Description
Patient condition Evaluate the severity and complexity of a patient’s illness or injury. Is ambulance transport essential based on medical necessity?
Distance to medical facility Consider the proximity of the patient to the nearest appropriate facility. Is the distance reasonable for ground transportation?
Mobility Review the patient’s vital signs scores such as the Glascow Coma Scale (GCS), blood pressure, and pain scale, to evaluate the patient's ability to safely access a vehicle.
Transport Risks Assess potential risks during transport. Does the patient's condition require specialized care enroute?

Non-Emergency: An ambulance responding to transport individual(s) who are not at immediate health risk but require clinical monitoring or supervision during transport and whose health might otherwise be at risk if transported by other means. Most transports occur between hospitals for intra-facility transfer, discharges, or routine yet medically necessary transports between a patient’s residence and a medical facility, such as dialysis treatments.

Typical medical necessity evaluation criteria for non-emergent transports
Criteria Description
Alternative Transportation Consider whether alternative transportation method, such as wheelchair vans or cars, are suitable and available for the patient.
Physician Certification Obtain certification from a physician documenting the medical necessity of non-emergency ambulance transport.
Scheduled Medical Appointments Verify if the transportation is for a scheduled medical appointment
Mobility Concerns Evaluate the patient’s ability to safely access and exit vehicle. Does the patient have mobility issues that make non-emergency ambulance transport necessary?

Non-emergency transportation requires the ambulance service to obtain a written Physician Certification Statement (PCS) or Letter of Medical Necessity (LOMN) from the attending physician or other licensed healthcare provider certifying that medical necessity requirements have been met. However, the mere presence of a signed PCS does not, by itself, demonstrate compliance with the medical necessity requirement.

Stay Up to Date

Medical necessity in ambulance coding is crucial to ensuring accurate reimbursement, maintaining quality care, and complying with regulatory requirements. As such, having in place a strategy for ongoing monitoring of coding practices and to keep coders and billers up to date with coding guidelines and changes in regulations is important to ensure patients receive the appropriate care for their conditions and diagnoses and that the services provided are documented correctly.

For a more detailed discussion and guidance on medical necessity in coding and billing for ambulance services, download Medical Necessity in Ambulance Coding today.

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