ModifiedColorado Rocky Mountain Health PlansPolicy MMP046.11

Hospital, Emergency, and Ambulance Services

Medicare Advantage policy governing coverage, medical necessity, and payment considerations for inpatient, outpatient, observation, and ambulance/emergency hospital services for UnitedHealthcare Medicare Advantage members.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyHospital, Emergency, and Ambulance Services

Policy CodePolicy MMP046.11

Change TypeRegulatory and reference updates

Effective DateJan 1, 2026

Next Review DateN/A

Key ActionProviders must document and retain medical record evidence that supports medical necessity for inpatient admission, including severity of illness and intensity of service.

SourceLink

POLICY UPDATE CHANGES

Updated reference link to the Calendar Year (CY) 2025 Medicare Hospital Outpatient Prospective Payment System and Ambulatory Surgical Center Payment System Proposed Rule in Coverage Rationale for Outpatient Hospital Services.

Updated reference link to the current policy title for Skilled Nursing Facility, Rehabilitation, Long-Term Acute Care Hospital, and Private Duty Nursing.

Updated References section to reflect the most current information.

Updated reference link to reflect the current policy title for Skilled Nursing Facility, Rehabilitation, Long-Term Acute Care Hospital, and Private Duty Nursing.

Updated reference link to the Calendar Year (CY) 2025 Medicare Hospital Outpatient Prospective Payment System and Ambulatory Surgical Center Payment System Proposed Rule.

Updated References section to reflect the most current information.

Archived previous policy version MMP046.10.

CY 2025Medicare rule year referenced

<48husual observation stay duration

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2-midnightsphysician expectation benchmark

Never Eventsprocedures not reimbursed

3ambulance coverage categories

Coverage Criteria for Hospital, Emergency, and Ambulance Services

Inpatient Admission Criteria

Covered when ALL of the following are met

Inpatient admission general criteria: The service is reasonable and necessary for diagnosis or treatment; the physician documents expectation that the patient will require hospital care spanning at least two midnights OR, if an exception, documentation demonstrates severity of illness and intensity of service supporting inpatient care; the medical record supports severity of illness and intensity of service.two-midnight benchmark

Concurrent review assesses complex medical factors

Observation Services Criteria

Covered when ALL of the following are met

Observation coverage: Ordered by a physician or other authorized individual; provided as ongoing short-term treatment, assessment, and reassessment to determine the need for inpatient admission or discharge; typically resolved and discharged or admitted within 24–48 hours (usually <48 hours, rarely >48 hours).<48 hours usual

All medically reasonable and necessary observation services are covered regardless of duration

Outpatient Hospital Services

Covered when ALL of the following are met

Outpatient hospital services: Services and supplies are furnished as an integral (although incidental) part of the physician's professional service in diagnosis or treatment; services are furnished on a physician's order and under physician supervision (physician on premises and involved in evaluation).

Part B covers diagnostic and therapeutic outpatient services except services specifically excluded

Covered Ambulance Transports

Ambulance transport is covered when ALL of the following are met

Emergency or danger to health: An emergency situation exists as defined in the Medicare Managed Care Manual Chapter 4, or other means of transportation would endanger the member's health.

Refer to Medicare Benefits Policy Manual, Chapter 10

Dispatch and transport context: Includes ambulance services dispatched through 911 or local equivalent or ambulance services where ambulance transport is the only safe means of transport given the member's condition.

Local Coverage Determinations (LCDs)/Local Coverage Articles (LCAs) and MAC policies apply

Emergency Services, Post-stabilization, and Follow-up

Services are covered when ALL of the following are met

Emergency/urgent definition met: The service meets Medicare definitions of emergency or urgently needed services per the Medicare Managed Care Manual, Chapter 4.

Post-stabilization definition met: Post-stabilization care is provided in accordance with the Medicare definition of post-stabilization and is clinically necessary following an emergency.

Refer to Medicare Managed Care Manual Chapter 4

Follow-up provider network: Follow-up care is preferred from deemed or contracted providers but will be covered if the continued care continues to meet the definition of emergency or urgently needed services.

Application of internal coverage criteria

UnitedHealthcare applies internal coverage criteria when Medicare statutes, regulations, NCDs, or LCDs are absent or allow flexibility.

Internal Criteria Application: UnitedHealthcare evaluates current relevant clinical evidence and widely used treatment guidelines to develop internal coverage criteria to determine whether items or services may be reasonable and necessary when Medicare source materials do not fully establish coverage criteria or explicitly allow broader coverage.

These internal criteria are applied only where Medicare statutes, regulations, NCDs, or LCDs are absent or allow flexibility.

Religious nonmedical health care institution (RNHCI) services and other care that are primarily for religious purposes or nonmedical residential support are not covered under this policy. In addition, services that are custodial, provided for convenience, or are not required for the diagnosis or treatment of illness or injury are excluded from coverage and payment. Providers should consult the member-specific benefit plan document for any applicable limits or prior authorization requirements for RNHCI-related care.

Ambulance transports where the member is not onboard (for example, moving an ambulance or personnel between facilities or transporting staff) are not covered. Separately billed paramedic charges for BLS/ALS when the ambulance supplier does not transport the beneficiary (such as a fire department response without transport) are not payable. Paramedic intercept and other separately billed EMS services are not covered unless all Medicare-specified requirements for those services are met; consult the Medicare Benefits Policy Manual and applicable MAC/LCD guidance for specific conditions.

Services identified as Never Events will not be reimbursed. Examples explicitly excluded from payment include: wrong surgical or invasive procedure performed on a patient, a surgical or invasive procedure performed on the wrong body part, and a surgical or invasive procedure performed on the wrong patient. These items follow the corresponding Medicare NCDs and will be denied for reimbursement per policy.

This policy is intended to guide coverage determinations but does not replace the member-specific benefit plan document. Benefit coverage for health services is determined by the member’s benefit plan document and applicable laws; in the event of a conflict between this policy and the member-specific plan document, the member-specific plan document supersedes this policy. For questions about individual member benefits, contact the number on the member ID card or refer to the Administrative Guide.

Hospital care that is primarily custodial, provided for the convenience of the patient, family, or provider, or is not required for the diagnosis or treatment of illness or injury is not appropriate for coverage or payment. Examples include long‑term custodial residential care and services that are part of routine recovery or preparation that are already included in payment for another covered service. When there is uncertainty about inpatient necessity, consider observation status.

Ambulance transportation is a transportation‑based benefit and is not covered when the member’s condition does not meet Medicare criteria for ambulance transport. If the ambulance supplier does not transport the member, no ambulance benefit exists and the transport-related charges will be denied. Refer to Medicare policy and applicable MAC/LCD guidance when evaluating ambulance medical necessity.

(Reserved) No additional content is specified for this section in the source document.

Coding, Codes, and Observation Duration

Inpatient-only referencesmixed

CMS Addendum E

Final HCPCS Codes That Would Be Paid Only as Inpatient Procedures

CMS / MAC references and local articlesmixed

Ambulance Services, LCD	Ambulance Services
Ambulance Services, LCA	Ambulance Services
A52917	Rural Air Ambulance Service Protocols

Referenced coding systemsmixed

CPT	Referenced for definitional purposes and coding guidance
CMS	Centers for Medicare & Medicaid Services coding/guidance referenced

Observation duration — usual thresholds

Usual observation durationUsually less than 24 hours; in most cases less than 48 hours; only rare and exceptional cases span more than 48 hours.

Typical decision windowMajority of observation decisions to discharge or admit can be made in less than 48 hours, often <24 hours.

Coverage regardless of durationAll medically reasonable and necessary observation services are covered regardless of actual duration.

Order requirementObservation services are covered only when ordered by a physician or another authorized individual per state licensure and hospital bylaws.

State paramedic intercept eligibility

Provider Requirements, Authorizations, and Documentation

Prior Authorization

Prior authorization for RNHCI services

Prior authorization and benefit period requirements apply to Religious Nonmedical Health Care Institution (RNHCI) services when those services are equivalent to hospital or extended care level of care. Members who elect RNHCI services are subject to the same prior authorization, benefit period, and all copayment/coinsurance rules that apply to hospital services. Providers without a contract must accept as payment in full the amounts the provider could collect under Original Medicare.

RNHCI services limited to members who elected RNHCI.
Same benefit restrictions and prior authorization requirements apply as for hospital services.
Non-contracted RNHCI providers must accept Original Medicare payment amounts.

Prior Authorization

Authorization requirements

Certain services (for example, bloodless medicine and surgery for some members) require authorization from the member's participating medical group/IPA. Authorization must be obtained before services are furnished when required; failure to obtain required authorization may result in financial responsibility for the member.

Background and Policy Scope

Inpatient admission decisions should be based on clinical judgment, including the severity of signs and symptoms, the medical predictability of adverse events, the need for diagnostic studies or interventions, and facility availability. A key benchmark used under Medicare is the two‑midnight expectation—the attending physician’s expectation that the patient will require hospital care spanning at least two midnights—which supports inpatient admission when documented. Concurrent review and thorough medical record documentation must demonstrate the severity of illness and intensity of services to substantiate inpatient status.

Definitions and Key Terms

Observation services — definition

DefinitionObservation services are a well-defined set of short-term treatment, assessment, and reassessment services to determine the need for inpatient admission or discharge.

Ordering authorityCovered only when ordered by a physician or an individual authorized by state licensure and hospital bylaws to admit patients or order outpatient tests.

Common use caseOften ordered for patients presenting to the emergency department who require a significant period of treatment or monitoring.

Patient statusWhen a physician orders observation care, the patient's status is outpatient; purpose is to decide on further treatment or inpatient admission.

Two-midnight benchmark

Two-midnight benchmarkPhysician expectation that the patient will require hospital care spanning at least two midnights is used as the benchmark for inpatient admission under Medicare.

Policy Summary

PayerColorado Rocky Mountain Health Plans

PolicyHospital, Emergency, and Ambulance Services

Policy CodePolicy MMP046.11

Change TypeRegulatory and reference updates

Effective DateJan 1, 2026

Next Review DateN/A

Key ActionProviders must document and retain medical record evidence that supports medical necessity for inpatient admission, including severity of illness and intensity of service.

SourceLink

On This Page

State-specific determination

Paramedic intercept eligibility is determined at the state level; some states meet PI requirements per Medicare guidance.

New York exampleThe State of New York meets the requirements for the paramedic intercept services benefit per Medicare Claims Processing Manual, Chapter 15, §20.1.4.

MAC determinationsSome Medicare Administrative Contractors (MACs) have determined certain states meet rural area requirements relevant to ambulance/PI coverage.

Reference guidanceRefer to the Medicare Claims Processing Manual and the Ambulance Services table for specific state and MAC determinations.

Bloodless medicine and/or surgery must be authorized by the member's Participating Medical Group/IPA.
Authorization requests cannot be guaranteed and depend on the capabilities of the participating medical group/IPA.

Prior Authorization

Authorization requirements for ambulance services

Ambulance services must meet Medicare emergency or medical-necessity criteria to be covered. Local Coverage Determinations (LCDs) and Local Coverage Articles (LCAs) apply where relevant; providers should follow those policies and obtain any required authorizations.

Emergency ambulance services covered when emergency exists or other transportation would endanger the member's health.
Non-covered examples: member condition does not meet Medicare criteria; transport when member not onboard; paramedic charges when member not transported.
Refer to Medicare Benefit Policy Manual Chapter 10 and applicable LCDs/LCAs.

Denial Risk

Triggers for denial

Certain events or conditions will trigger claim denials, including services that are not reasonable and necessary, services already included in another covered service, and Medicare "Never Events" such as wrong patient/body part/procedure. Ambulance transports that do not meet Medicare criteria may also be denied.

Services not reasonable and necessary may be denied.
Services that are part of another covered service (e.g., postoperative monitoring during a standard recovery period) may be denied.
Never Events (wrong procedure, wrong body part, wrong patient) are not reimbursed.
Ambulance transports not meeting Medicare criteria are non-covered and may be denied.

Documentation Required

Recordkeeping and member-specific benefits

Providers are expected to retain or have access to appropriate documentation to support coverage determinations and must follow the member-specific benefit plan document to determine coverage, exclusions, and limitations. In the event of a conflict, the member's benefit plan supersedes this policy. Contact customer service or consult the Administrative Guide for member-specific questions.

Providers must retain or be able to produce documentation upon request to support medical necessity and coverage.
Benefit coverage is determined by the member-specific benefit plan document; that document supersedes this policy if there is a conflict.
For member-specific benefit information, call the number on the member ID card or refer to the Administrative Guide.

Documentation Required

Retention of documentation

Providers must retain documentation that supports inpatient admission medical necessity (severity of illness, intensity of services) and be prepared for concurrent review. Failure to retain or produce required documentation may result in denial or recoupment.

Documentation must clearly support inpatient admission (severity of illness, intensity of service) per Medicare criteria.
Concurrent review assesses whether documented medical factors support inpatient admission.
Failure to retain/produce documentation may lead to denial or recoupment.

Billing Rule

Accurate claims submission

Providers are responsible for submitting accurate claims using CPT, CMS, and other applicable coding guidelines. References to coding systems are for definitional purposes and do not guarantee payment. When a delegate manages utilization management and prior authorization for a member's plan, providers must follow the delegate's prior authorization and documentation requirements.

Submit accurate claims and follow CPT/CMS coding guidelines.
Coding references do not imply entitlement to reimbursement or guarantee payment.
When a delegate administers prior authorization for a plan, follow the delegate's requirements.

Note

Provider action placeholder — not specified in this document section

(Action required: see applicable callouts above.)

Physician responsibilityThe practitioner responsible for the patient's hospital care decides whether to admit as inpatient, using the two-midnight expectation among other clinical factors.

Documentation requirementDocumentation must clearly support the medical necessity of inpatient admission, evidencing severity of illness and intensity of service to warrant inpatient care.

Concurrent reviewConcurrent review assesses whether complex medical factors documented in the record support inpatient medical necessity (42 CFR § 412.3(d)(1),(d)(3)).

Services covered per Medicare Managed Care Manual Chapter 4

Emergency and urgently needed servicesCovered when Medicare Managed Care Manual, Chapter 4 definitions of emergency and urgently needed services are met.

Post-stabilization carePost-stabilization care services are covered when they meet the Medicare Managed Care Manual, Chapter 4 definition of post-stabilization.

Follow-up careFollow-up care is covered if it continues to meet the definition of emergency or urgently needed services; preference for deemed or contracted providers does not limit coverage if criteria met.

Post-stabilization Care

Post-stabilization definitionPost-stabilization care services are care following an emergency that meet the Medicare Managed Care Manual, Chapter 4, §20.5.1 definition of post-stabilization.

Coverage conditionPost-stabilization services are covered when the Medicare definition and criteria are met.

Reference guidanceRefer to the Medicare Managed Care Manual, Chapter 4, §20.5.1 for post-stabilization coverage guidelines.

Internal criteria used when Medicare guidelines are absent or flexible

When appliedUnitedHealthcare applies internal coverage criteria when Medicare statutes, regulations, NCDs, or LCDs are absent or explicitly allow flexibility.

Evidence basisInternal criteria are developed through evaluation of current relevant clinical evidence and widely used treatment guidelines to determine reasonable and necessary care.

Role of Medicare source materialsMedicare source materials are primary; where conflict exists, Medicare materials apply and internal criteria are used only where guidance is lacking or flexible.

Policy statusMedicare Advantage Policies represent a portion of resources used for UnitedHealthcare coverage decisions and may be modified by publishing new versions.