CurrentHighmark Blueshield NenyPolicy N/A

Certificate of Medical Necessity (CMN) for Oxygen Therapy

Form and clinical requirements for documenting medical necessity when requesting home oxygen therapy equipment and services; affects ordering providers and suppliers submitting CMNs.

Policy Summary

PayerHighmark Blueshield Neny

PolicyCertificate of Medical Necessity (CMN) for Oxygen Therapy

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionInclude a typed office note, dated ABG or room‑air oxygen saturation within 30 days, physician signature, and a prescription specifying equipment and highest flow (LPM).

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

30 daysABG or saturation must be within

56-59 mm Hg / 89%Physio threshold prompting extra criteria

4 LPMTest required if prescribed >4 LPM

Rev. 06/28/2011Form revision date

Coverage Criteria for Home Oxygen Therapy

Initial Oxygen Therapy Criteria

Covered when ALL of the following are met:

Documentation and testing: Typed office note with pertinent clinical information and lab results; arterial blood gas (PO2) or oxygen saturation performed on room air within 30 days; name of the physician/provider performing the test (cannot be a DME or respiratory equipment provider per Medicare); physician signature and prescription specifying requested equipment type and highest flow (LPM).ABG/%Sat within 30 days

See form fields for required items (test date, tester identity, equipment requested, highest LPM).

Severity and stability: Diagnosis documented that disease is severe and expected to improve with oxygen therapy; documentation that alternative cardiopulmonary treatments were considered/tried and found ineffective; documentation that the patient was in a chronic stable state (not during an acute illness) when the ABG or saturation was performed.stable state documented

Form asks Y/N for severity, alternative measures, and stable-state status.

Policy Summary

PayerHighmark Blueshield Neny

PolicyCertificate of Medical Necessity (CMN) for Oxygen Therapy

Policy CodePolicy N/A

Change TypeNo material change

Effective DateN/A

Next Review DateN/A

Key ActionInclude a typed office note, dated ABG or room‑air oxygen saturation within 30 days, physician signature, and a prescription specifying equipment and highest flow (LPM).

SourceLink

On This Page

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Form Identifiers and Oxygenation Thresholds

Form identifiersmixed

No codes listed

Oxygenation thresholds and testing conditions

Timing of testABG or room‑air oxygen saturation must be performed on room air within 30 days of the request.

Primary physiologic thresholdsArterial PO2 and/or oxygen saturation measured on room air; qualifying criterion is PO2 ≤59 mm Hg or oxygen saturation ≤89% (form prompts further evaluation if PO2 56–59 mm Hg or O2 sat = 89%).

Flow-related testing requirementIf prescribed highest flow is >4 LPM, submit recent test results obtained while the patient was on 4 LPM (ABG PO2 and/or oxygen saturation on 4 LPM).

Test conditions to documentIndicate whether measurement was at rest/ADLs, during exercise, or during sleep (automated sleep oximetry), and name of provider who performed test (cannot be DME/supplier).

Provider Responsibilities and Documentation Requirements

Documentation Required

Prescription and test-results requirement

Prescription must specify the type of equipment requested and the highest flow (LPM) ordered. If >4 LPM is prescribed, the provider must supply recent test results performed while the patient was receiving 4 LPM oxygen (date of test and either ABG PO2 on 4 L O2 or room-air oxygen saturation on 4 L O2).

Specify equipment: stationary only, portable only, or both.
Document highest flow ordered (LPM).
If >4 LPM ordered, include test results on 4 LPM with date and values.

Denial Risk

Timely oxygenation test

An ABG (PO2) or room-air oxygen saturation must be performed and documented within 30 days of the request. Failure to provide a dated test within this 30-day window may result in denial of coverage.

Date of most recent assessment (ABG or % saturation) must be within 30 days of the request.
Test must be performed on room air unless documenting tests on 4 LPM per higher-flow requirement.

Denial Risk

Stable-state requirement

If the oxygenation test was performed during an acute illness, the provider must document a subsequent stable-state test demonstrating chronic stable hypoxemia. Tests done during acute illness without later stable-state documentation may be denied.

Confirm patient was in a chronic stable state at time of ABG or saturation (not during acute illness).
If initial test during acute illness, provide a later stable-state test before coverage will be approved.

Documentation Required

Tester identity

Document the name of the physician/provider who performed the oxygenation test. Per Medicare rules, the tester cannot be a DME supplier or respiratory equipment provider; the identity of the testing provider must be included in the record.

Record tester name and credentials.
Tester must not be a DME or respiratory equipment supplier per Medicare.

Documentation Required

Conservative measures documentation

Provider must document consideration and/or trial of alternative cardiopulmonary treatments and state that the disease is severe and is expected to improve with oxygen therapy. Include a typed office note and relevant lab results supporting clinical rationale.

Typed office note with pertinent clinical information.
Answer whether disease is severe and will improve with therapy (Y/N).
Document tried/considered alternative measures to improve cardiopulmonary function and that they were ineffective (Y/N).
Include lab results if available to support rationale.

Key Definitions

Stable state

DefinitionStable state = patient was not in an acute illness when the ABG or oxygen saturation was performed (form asks: 'Was patient in a chronic stable state at time ABG or saturation performed? (Not during an acute illness)?').

Documentation requirementProvider must indicate Yes/No on the form that the patient was in a chronic stable state when testing occurred; lack of a stable‑state test may trigger denial.

Implication for testing validityTests performed during acute illness are not acceptable without a separate stable‑state test recorded on the form.

Qualifying hypoxemia (borderline values)

Triggering rangePO2 in the range 56–59 mm Hg or oxygen saturation of 89% prompts additional qualifying conditions to be documented.

Required additional conditionsAt least one of: dependent edema due to congestive heart failure; cor pulmonale or pulmonary hypertension (document diagnostic testing); hematocrit >56%; or other specified condition.

Where documentedForm includes a checklist (item 7) for these secondary qualifying conditions to support eligibility when PO2/O2 sat are in the borderline range.

Background

Long‑term oxygen therapy is prescribed for patients with chronic hypoxemia to improve systemic oxygenation and clinical outcomes. Coverage decisions require objective, contemporaneous measurements of oxygenation obtained on room air (ABG PO2 or pulse oximetry) and documentation that the patient was in a stable state when tested. The Certificate of Medical Necessity (CMN) is structured to capture the date of the most recent ABG or oxygen saturation (must be within 30 days), numeric test results, the clinical diagnosis, confirmation that disease is severe and likely to improve with oxygen, consideration of alternative treatments, the testing conditions (rest, exertion, or sleep), and the name of the provider who performed the test.