Medical Necessity

Original Effective Date
For services performed on or after 10/01/2015
Revision Effective Date
For services performed on or after 01/01/2016

CMS Manual Chapter 10(Rev. 243, 04-13-18)

Medical Necessity

Medical necessity is established when the patient’s condition is such that use of any other method of transportation is contraindicated. In any case in which some means of transportation other than an ambulance could be used without endangering the individual’s health, whether or not such other transportation is actually available, no payment may be made for ambulance services.

It is important to note that the presence (or absence) of a physician’s order (PCS Form) for a transport by ambulance does not necessarily prove (or disprove) whether the transport was medically necessary.

Emergency Ambulance Services

Medicare will cover emergency ambulance services when the services are medically necessary, meet the destination limits of closest appropriate facilities and are provided by an ambulance service that is licensed by the state. Emergency response means responding immediately at the Basic Life Support (BLS) or Advanced Life Support 1 (ALS1) level of service to a 911 call or the equivalent. An immediate response is one in which the ambulance supplier begins as quickly as possible to take the steps necessary to respond to the call.

The patient’s condition is an emergency that renders the patient unable to be safely transported to the hospital in a moving vehicle (other than an ambulance) for the amount of time required to complete the transport. Emergency ambulance services are services provided after the sudden onset of a medical condition. For the purposes of this LCD, acute signs or symptoms of sufficient severity must manifest the emergency medical condition such that the absence of immediate medical attention could reasonably be expected to result in one or more of the following:

  • Place the patient’s health in serious jeopardy.
  • Cause serious impairment to bodily functions.
  • Cause serious dysfunction of any body organ or part.

Non-Emergency Ambulance Service

Ambulance services are covered in the absence of an emergency condition in either of the two general categories of circumstances that follow:

  1. The patient being transported has, at the time of ground transport, a condition such that all other methods of ground transportation (e.g., taxi, private automobile, wheelchair van or other vehicle) are contraindicated. In this circumstance, contraindicated means that the patient cannot be transported by any other means from the origin to the destination without endangering the individual’s health. Having or having had a serious illness, injury or surgery does not necessarily justify Medicare payment for ambulance transportation, thus a thorough assessment and documented description of the patient’s current state is essential for coverage. All statements about the patient’s medical condition must be validated in the documentation using contemporaneous objective observations and findings. See Table I of medical conditions below for examples of findings required for coverage of ambulance transportation.
  2. The patient is before, during and after transportation, bed-confined. For the purposes of this LCD, “bed-confined” means the patient must meet all of the following three criteria:
    • Unable to get up from bed without assistance.
    • Unable to ambulate.
    • Unable to sit in a chair (including a wheelchair).

As stated in the bullet above, statements about the patient’s bed-bound status must be validated in the record with contemporaneous objective observations and findings as to the patient’s functional physical or mental limitations that have rendered him bed-bound.

The term “bed confined” is not synonymous with “bed rest” or “nonambulatory”. Bed-confinement, by itself, is neither sufficient nor is it necessary to determine the coverage for Medicare ambulance benefits. It is simply one element of the beneficiary’s condition that may be taken into account in the A/B MAC (A)’s or (B)’s determination of whether means of transport other than an ambulance were contraindicated.

Non-emergency ambulance transportation is not covered for patients who are restricted to bed rest by a physician’s instructions but who do not meet the above three criteria. If some means of transportation other than an ambulance (i.e., private car, wheelchair van, etc.) could be utilized without endangering the individual’s health, whether such other transportation is actually available, no payment may be made for ambulance service.

Destination Specific

Medicare covers ambulance transports (that meet all other program requirements for coverage) only to the following destinations:
• Hospital;
• Critical Access Hospital (CAH);
• Skilled Nursing Facility (SNF);
• From a SNF to the nearest supplier of medically necessary services not available at the SNF where the beneficiary is a resident and not in a covered Part A stay, including the return trip;
• Beneficiary’s home;
• Dialysis facility for ESRD patient who requires dialysis; or
A physician’s office is not a covered destination.

As a general rule, only local transportation by ambulance is covered, and therefore, only mileage to the nearest appropriate facility equipped to treat the patient is covered.

Tables of Medical Conditions

The attached tables illustrate Medicare’s expectations with respect to the severity of the patient’s condition to justify payment for ambulance transportation services when all other coverage and payment conditions are met. Though not all-inclusive, the following table lists medical conditions for which ambulance transportation is commonly required and can be used to judge relative severity of conditions not listed.

Ambulance Services (Ground Ambulance)
I. Medical Conditions

Complaint or Symptom Condition Requirement Examples of Symptoms and Findings Necessary
(and Documented) for Coverage
Abdominal pain Accompanied by other signs or symptoms Associated symptoms include nausea, vomiting, fainting. Associated signs include tender or pulsatile mass, distention, rigidity, rebound tenderness on exam, guarding.
Abnormal cardiac rhythm/cardiac dysrhythmia Symptomatic or potentially life-threatening arrhythmia Necessary symptoms include syncope or near syncope, chest pain and dyspnea. Signs required include severe bradycardia or tachycardia (rate < 60 or > 120), signs of congestive heart failure. Examples include junctional and ventricular rhythms, non-sinus tachycardias, PVCs > 6/min, bi- and trigeminy, ventricular tachyarrhythmias, PEA, asystole. Patients are expected to have conditions that require monitoring during and after transportation.
Abnormal skin signs Includes diaphoresis, cyanosis, delayed capillary refill, diminished skin turgor, mottled skin. Presence of other emergency conditions
Alcohol or drug intoxication Severe intoxication Unable to care for self. Unable to ambulate. Altered level of consciousness. Airway may or may not be at risk.
Allergic reaction Potentially life-threatening manifestations Includes rapidly progressive symptoms, prior history of anaphylaxis, wheezing, oral/facial/laryngeal edema
Animal bites/sting/ envenomation Potentially life- or limb- threatening Symptoms of specific envenomation, significant face, neck, trunk and extremity involvement. Special handling and/or monitoring required. Presence of other emergency conditions.
Sexual assault With significant external and/or internal injuries
Blood glucose Abnormal <80 or >250 with symptoms Signs include altered mental status (altered beyond baseline function), vomiting, significant volume contraction, significant cardiac dysfunction.
Back pain (see general pain listing below) Sudden onset, severe non-traumatic pain suggestive of cardiac or vascular origin or requiring special positioning only available by ambulance 7–10 on 10-point severity scale. Neurologic symptoms and/or signs, absent leg pulses, pulsatile abdominal mass, concurrent chest or abdominal pain
Respiratory arrest Includes apnea or hypoventilation requiring ventilatory assistance and airway management
Respiratory distress, shortness of breath, need for supplemental oxygen Objective evidence of abnormal respiratory function Includes tachypnea, labored respiration, hypoxemia requiring oxygen administration. Includes patients who require advanced airway management such as ventilator management, apnea monitoring for possible intubation and deep airway suctioning. Includes patients who require positioning not possible in other conveyance vehicles. Note that oxygen administration absent signs or symptoms of respiratory distress is, by itself, an inadequate reason to justify ambulance transportation in a patient capable of self-administration of oxygen. Patient must require oxygen therapy and be so frail as to require assistance of medically trained personnel.
Cardiac arrest with resuscitation in progress
Chest pain (non-traumatic) Cardiac origin suspected. Obvious non-emergent cause not identified Pain characterized as severe, tight, dull or crushing, substernal, epigastric, left-sided chest pain. Especially with associated pain of the jaw, left arm, neck, back, GI symptoms (such as nausea, vomiting), arrhythmias, palpitations, difficulty breathing, pallor, diaphoresis, alteration of consciousness. Atypical pain accompanied by nausea and vomiting, severe weakness, feeling of impending doom or abnormal vital signs.
Choking episode Respiratory or neurologic impairment
Cold exposure Potentially life- or limb- threatening Findings include temperature < 95º F, signs of deep frost bite or presence of other emergency conditions.
Altered level of consciousness (non-traumatic) Neurologic dysfunction in addition to any baseline abnormality Acute condition with Glasgow Coma Scale <15 or transient symptoms of dizziness associated with neurologic or cardiovascular symptoms and/or signs or abnormal vital signs
Convulsions/seizures Active seizing or immediate post-seizure at risk of repeated seizure and requires medical monitoring/observation Conditions include new onset or untreated seizures or history of significant change in baseline control of seizure activity. Findings include ongoing seizure activity, postictal neurologic dysfunction.
Non-traumatic headache Associated neurologic signs and/or symptoms or abnormal vital signs
Heat exposure Potentially life-threatening Findings include hot and dry skin, core temperature >105º, neurologic dysfunction, muscle cramps, profuse sweating, severe fatigue.
Hemorrhage Potentially life-threatening Includes uncontrolled bleeding with signs of shock and active severe bleeding (quantity identified) ongoing or recent with potential for immediate rebleeding.
Infectious diseases requiring isolation procedures/public health risk The nature of the infection or the behavior of the patient must be such that failure to isolate poses significant risk of spread of a contagious disease. Infections in this category are limited to those infections for which isolation is provided both before and after transportation.
Hazardous substance exposure The nature of the exposure should be such that potential injury is likely. Toxic fume or liquid exposure via inhalation, absorption, oral, radiation, smoke inhalation
Medical device failure Life- or limb-threatening malfunction, failure or complication Malfunction of ventilator, internal pacemaker, internal defibrillator, implanted drug delivery device, O 2 supply malfunction, orthopedic device failure
Neurologic dysfunction Acute or unexplained neurologic dysfunction in addition to any baseline abnormality Signs include facial drooping, loss of vision without ophthalmologic explanation, aphasia, dysphasia, difficulty swallowing, numbness, tingling extremity, stupor, delirium, confusion, hallucinations, paralysis, paresis (focal weakness), abnormal movements, vertigo, unsteady gait/balance.
Pain not otherwise specified in this table Pain is the reason for the transport. Acute onset or bed-confining. Pain is severity of 7–10 on 10-point severity scale despite pharmacologic intervention. Patient needs specialized handling to be moved. Other emergency conditions are present or reasonably suspected. Signs of other life- or limb-threatening conditions are present. Associated cardiopulmonary, neurologic, or peripheral vascular signs and symptoms are present.
Poisons ingested, injected, inhaled or absorbed, alcohol or drug intoxication Potentially life-threatening Requires cardiopulmonary and/or neurologic monitoring and support and/or urgent pharmacologic intervention. Includes circumstances in which quantity and identity of agent known to be life-threatening; instances in which quantity and identity of agent are not known but there are signs and symptoms of neurologic dysfunction, abnormal vital signs, or abnormal cardiopulmonary function. Also, includes circumstances in which quantity and identity of agent are not known but life-threatening poisoning reasonably suspected.
Complication of pregnancy/childbirth and postoperative procedure complications Requires special handling for transport Includes major wound dehiscence, evisceration, organ prolapse, hemorrhage or orthopedic appliance failure
Psychiatric/behavioral Is expressing active signs and/or symptoms of uncontrolled psychiatric condition or acute substance withdrawal. Is a threat to self or others requiring restraint (chemical or physical) or monitoring and/or intervention of trained medical personnel during transport for patient and crew safety. Transport is required by state law/court order. Includes disorientation, suicidal ideations, attempts and gestures, homicidal behavior, hallucinations, violent or disruptive behavior, sign/symptoms or DTs, drug withdrawal signs/symptoms, severe anxiety, acute episode or exacerbation of paranoia. Refer to definition of restraints in the CFR, Section 482.13(e). For behavioral or cognitive risk such that patient requires attendant to assure patient does not try to exit the ambulance prematurely, see CFR, Section 482.13(f)(2) for definition.
Fever Significantly high fever unresponsive to pharmacologic intervention or fever with associated symptoms Temperature after pharmacologic intervention >102º (adult)

Temperature after pharmacologic intervention >104º (child)

Associated neurologic or cardiovascular symptoms/signs, other abnormal vital signs

Gastrointestinal distress Accompanied by other signs or symptoms Severe nausea and vomiting or severe, incapacitating diarrhea with evidence of volume depletion, abnormal vital signs or neurologic dysfunction
General mobility issues and bed confinement Patient’s physical condition is such that patient risks injury during vehicle movement despite restraints or positioning and/or record demonstrates specialized handling required and provided This may be due to any or multiple of the conditions listed above. All conditions that contribute to general mobility issues must be adequately described. Includes conditions such as:

  • Decubitus ulcers on sacrum or buttocks that are grade 3 or greater for transfers requiring more than 60 minutes of sitting.
  • Lower extremity contractures that are of sufficient degree as to prohibit sitting in a wheelchair (severe fixed contractures at or proximal to the knee).
  • Unstable joints. Includes flail weight-bearing joints following joint surgery. Includes other patients who, in the expressed opinion of the operating surgeon, must absolutely bear no weight on a postoperative joint or patients who are incapable of protecting the joint without the assistance of the trained medical ambulance personnel. Patients who have undergone successful weight bearing joint repair/replacement and those who have successfully undergone long-bone fracture repair (and who are not otherwise immobilized in casts that prohibit sitting) will generally not be included.
  • Severely debilitating chronic neurological conditions such as degenerative conditions or strokes with severe sequelae. Neurological deficits must be described.
  • Morbid obesity (as a sole qualifying condition) causing the patient to meet the regulatory definition of bed-confined. Medicare does not expect this to occur with persons whose BMI is <80.

II. Conditions – Trauma

On-Scene Condition (General)

On-Scene Condition (Specific)

Comments and Examples
(Not All-Inclusive)

Major trauma As defined by ACS Field Triage Decision Scheme Trauma with one of the following: Glasgow < 14; systolic BP < 90; RR < 10 or > 29; all penetrating injuries to head, neck, torso, extremities proximal to elbow or knee; flail chest; combination of trauma and burns; pelvic fracture; two or more long-bone fractures; open or depressed skull fracture; paralysis; severe mechanism of injury including: ejection, death of another passenger in same patient compartment, falls > 20 feet, 20-inch deformity in vehicle or 12-inch deformity of patient compartment, auto pedestrian/bike, pedestrian thrown/run over, motorcycle accident at speeds > 20 miles per hour and rider separated from vehicle
Other trauma Need to monitor or maintain airway or immobilize head/neck Decreased level of consciousness, bleeding into airway, significant trauma to head, face or neck
Hemorrhage Potentially life-threatening hemorrhage Includes uncontrolled bleeding with signs of shock and active severe bleeding (quantity identified), ongoing or recent, with potential for immediate rebleeding
Suspected fractures/dislocations Suspected fracture or dislocation requires splinting/immobilization and renders patient unable to be transported by another vehicle Includes suspected fractures or dislocations of spine and long bones and joints proximal to knee and elbow. The record will demonstrate history of significant trauma and or findings to support such suspicions.
Penetrating extremity injuries Life-or limb-threatening injury Uncontrolled hemorrhage, compromised neurovascular supply, uncontrollable pain requiring pharmacologic intervention
Traumatic amputations Life-threatening injury or reattachment opportunity exists
Suspected internal, head, chest or abdominal injuries Signs of closed head injury, open head injury, pneumothorax, hemothorax, abdominal bruising, positive abdominal signs on exam, internal bleeding criteria, evisceration
Burns Major: per American Burn Association (ABA) Partial thickness burns > 10 percent Total Body Surface Area (TBSA); involvement of face, hands, feet, genitalia, perineum or major joints; third-degree burns; electrical, chemical, inhalation burns with pre-existing medical disorders; burns and trauma
Eye injuries Acute vision loss or blurring, severe pain or chemical exposure, penetrating, severe lid lacerations

Special Considerations Regarding Beneficiary Death

Payment for ambulance services in circumstances in which the beneficiary dies is based on the time of the beneficiary’s death related to the time of the call for service and transport.

In cases where the beneficiary is pronounced dead after the ambulance is called but before the ambulance arrives at the scene, payment may be made for a BLS service. Neither mileage nor a rural adjustment would be paid. In cases where the beneficiary is pronounced dead after being loaded into the ambulance (regardless of whether the pronouncement is made during or subsequent to the transport), payment is made following the usual rules of payment as if the beneficiary had not died. This scenario includes a determination of Dead on Arrival (DOA) at the facility to which the beneficiary was transported. Please see IOM, Pub. 100-02, Medicare Benefit Policy Manual, Chapter 10, Section 10.2.6 for additional information.


Medicare does not cover the following services:

  • Transportation in Ambi-buses, ambulettes (Mobility Assistance Vehicle (MAV)), Medi-cabs, vans, privately owned vehicles, taxicabs.
  • Transportation via Mobile Intensive Care Unit (MICU) ( if billed under Medicare Part A).
  • Parking fees.
  • Tolls for bridges, tunnels and highways.
  • Medicare does not provide payment for “Ambulance response and treatment, no transport (A0998).”

Notice: This LCD imposes diagnosis limitations that support diagnosis to procedure code automated denials. However, services performed for any given diagnosis must meet all of the indications and limitations stated in this policy, the general requirements for medical necessity as stated in CMS payment policy manuals, any and all existing CMS national coverage determinations, and all Medicare payment rules.

As published in CMS IOM Pub. 100-08, Medicare Provider Integrity Manual, Chapter 13, Section 13.5.1, in order to be covered under Medicare, a service shall be reasonable and necessary. When appropriate, contractors shall describe the circumstances under which the proposed LCD for the service is considered reasonable and necessary under Section 1862(a)(1)(A). Contractors shall consider a service to be reasonable and necessary if the contractor determines that the service is:

  • Safe and effective.
  • Not experimental or investigational (exception: routine costs of qualifying clinical trial services with dates of service on or after September 19, 2000, that meet the requirements of the Clinical Trials NCD are considered reasonable and necessary).
  • Appropriate, including the duration and frequency that is considered appropriate for the service, in terms of whether it is:
    • Furnished in accordance with accepted standards of medical practice for the diagnosis or treatment of the patient’s condition or to improve the function of a malformed body member.
    • Furnished in a setting appropriate to the patient’s medical needs and condition.
    • Ordered and furnished by qualified personnel.
    • One that meets, but does not exceed, the patient’s medical needs.
    • At least as beneficial as an existing and available medically appropriate alternative.

Jurisdiction L Prior Authorization

Please refer to the Prior Authorization area on the Novitas website using the following URL: (please copy into your browser)

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