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Modifiedsierra health and lifePolicy 2026T0632J

Hyperbaric Oxygen Therapy and Topical Oxygen Therapy

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Defines medical necessity and investigational status for hyperbaric oxygen therapy (HBOT), mild HBOT, and topical oxygen therapy for UnitedHealthcare Commercial and Individual Exchange plans; applies to providers treating wounds and related conditions.

Policy Summary

Payersierra health and life

PolicyHyperbaric Oxygen Therapy and Topical Oxygen Therapy

Policy CodePolicy 2026T0632J

Change TypeContent update & archival of prior version

Effective DateMay 1, 2026

Next Review DateN/A

Key ActionConfirm member-specific prior authorization requirements and document indication, disease stage, prior therapies, and planned HBOT regimen before requesting coverage.

SourceLink

POLICY UPDATE CHANGES

Updated Description of Services, Clinical Evidence, FDA, and References sections to reflect the most current information.

16+conditions listed as medically necessary for HBOT

>=1.4 ATAminimum pressure to meet HBOT definition

Not necessarymild HBOT status

Unproventopical oxygen therapy status

30-60typical sessions for radiation injury

within 2 weekspreferred window for ISSHL

Coverage Criteria for HBOT and TOT

Medically Necessary Indications for HBOT

Covered when ALL of the following apply for each listed condition:

Medically necessary indications: Acute traumatic peripheral ischemia/insufficiency (e.g., crush injury, reattachment of severed limbs, compartment syndrome); Air or gas embolism; Severe anemia when transfusion is refused/delayed/unavailable; Avascular necrosis (aseptic osteonecrosis); Carbon monoxide poisoning; Central retinal artery occlusion; Chronic osteomyelitis refractory to medical and surgical management; Clostridial myonecrosis (gas gangrene); Compromised skin grafts/flaps; Cyanide poisoning associated with carbon monoxide poisoning; Decompression sickness; Delayed radiation injuries (soft tissue and bony necrosis); Diabetic lower extremity wounds; Idiopathic sudden sensorineural hearing loss; Intracranial abscess; Necrotizing soft tissue infections; Thermal burns, second or third degree.

Each listed condition is designated medically necessary per policy text

Not Medically Necessary / Unproven

Not medically necessary / unproven: HBOT for all indications not specifically listed as medically necessary is unproven and not medically necessary; Mild hyperbaric oxygen therapy (mHBOT; low-pressure fabric chambers delivering <1.4 ATA) is unproven and not medically necessary for any indication; Topical oxygen therapy (TOT) is unproven and not medically necessary for treatment of wounds or ulcers based on insufficient evidence.

Policy Summary

Payersierra health and life

PolicyHyperbaric Oxygen Therapy and Topical Oxygen Therapy

Policy CodePolicy 2026T0632J

Change TypeContent update & archival of prior version

Effective DateMay 1, 2026

Next Review DateN/A

Key ActionConfirm member-specific prior authorization requirements and document indication, disease stage, prior therapies, and planned HBOT regimen before requesting coverage.

SourceLink

On This Page

Policy explicitly states these exclusions

Avascular necrosis (FHN)

Avascular necrosis (femoral head): Covered when criteria below are met

AVN initial/adjunct therapy: Patient is an adult with imaging-confirmed femoral head osteonecrosis in early stages (Ficat I–II) or precollapse (early Ficat III) AND documented symptoms (e.g., hip pain, functional impairment) AND a documented rationale for HBOT as primary or adjunct therapy (for example, as an alternative to or combined with core decompression).Ficat stage I–II or early/precollapse III

Society guidance (ECHM, UHMS) and cohort reviews support HBOT in early-stage FHN; combined HBOT+core decompression may offer additional benefit in selected stage II cases

Carbon monoxide poisoning

Carbon monoxide (CO) poisoning: Covered when ALL of the following are met

CO poisoning with indications for HBOT: Acute CO poisoning with symptomatic or high‑risk features such as altered consciousness, focal neurological signs, cardiac ischemia, severe symptoms, or pregnancy OR other selection per specialty guidance (ACEP/ECHM/UHMS); documentation of timing from exposure and prior oxygen therapies must be provided.consider early treatment; optimal benefit with minimal delay

Guideline societies support selective HBOT for symptomatic/high‑risk CO patients though RCT evidence is mixed

Central retinal artery occlusion

Central retinal artery occlusion (CRAO): Covered when ALL of the following are met

CRAO time-sensitive HBOT: Sudden, painless loss of vision diagnosed as central retinal artery occlusion with presentation within 24 hours of symptom onset (or as soon as possible) AND documented baseline and planned follow-up visual acuity assessments and treatment plan (initial HBOT session of ~90 minutes with further sessions guided by response).presentation within 24 hours preferred

UHMS and ECHM recommend prompt HBOT for CRAO; meta-analyses show potential visual benefit when treatment is timely

Chronic refractory osteomyelitis

Chronic refractory osteomyelitis: Covered when ALL of the following are met

Refractory osteomyelitis adjunct HBOT: Documented chronic osteomyelitis that is refractory to standard therapy, defined by prior culture-directed antibiotics and surgical debridement, with ongoing multidisciplinary management AND documentation that HBOT is being used as an adjunctive measure to aid infection eradication or limb salvage. Treatment course and monitoring plan should be specified (ECHM suggests a course of ~60 sessions over ~11–12 weeks before judging effect).prior antibiotics and surgical debridement

Systematic reviews and society guidance support HBOT as an adjunct in refractory osteomyelitis with high reported remission in observational data

Society-supported Indications

Covered when supported by specialty society recommendations and clinical context

Infection indications: Refractory osteomyelitis and clostridial myonecrosis/myositis (gas gangrene) or spreading clostridial cellulitis with systemic toxicity — HBOT when used as an adjunct to culture-directed antibiotics and surgical debridement per society guidance.society guideline concordance

UHMS and ECHM recommend HBOT combined with surgery and antibiotics for these infections

Decompression illness/air or gas embolism: Recompression therapy (HBOT) is standard of care for decompression sickness and symptomatic air/gas embolism.standard of care

Widely accepted treatment though RCT data limited

Delayed radiation injury (LRTI): Late radiation-induced soft tissue or bony necrosis (including mandibular ORN, hemorrhagic cystitis, proctitis) when multidisciplinary evaluation supports HBOT as adjunctive therapy and protocols follow guideline ranges (commonly 30–60 sessions at 2.0–2.5 ATA for 90–120 minutes).multidisciplinary assessment and guideline-concordant course

ECHM and UHMS recommend HBOT for specific LRTI manifestations

Compromised skin grafts and flaps: Early HBOT for compromised grafts/flaps or flap salvage when clinical assessment documents graft/flap compromise and HBOT is used alongside surgical management; evidence is mixed and may require stronger justification for coverage in individual cases.early initiation; combine with surgical care

ECHM suggests parameters (approx. 203–253 kPa for ≥60 minutes) though ECRI notes limited high-quality trial evidence

Adjunctive HBOT for Diabetic Foot Ulcers

Covered when ALL of the following are met (DFU = diabetic foot ulcer):

DFU adjunctive HBOT coverage: 1) Ulcer is diabetic lower extremity wound meeting Wagner grade 2–4 (evidence strongest for grades 2–4) OR Wagner grade ≥3 per UHMS when aimed at amputation risk reduction; 2) Adequate standard wound care has been provided and documented with failure to improve after 4–6 weeks (or 30 days) OR persistent nonhealing despite standard therapy; 3) Adequate perfusion has been documented or surgical/vascular options assessed; 4) HBOT will be delivered per accepted protocols (for example, 2.0–2.5 ATA for 90–120 minutes per session) as adjunctive therapy with planned course and monitoring documented.Wagner grade and prior conservative therapy

Systematic reviews and guideline statements (SVS/IWGDF/UHMS/ECHM) support adjunctive HBOT in selected DFUs

HBOT for Delayed Radiation Injury

Covered when ALL of the following are met (Radiation injury):

Radiation-induced tissue injury: 1) Diagnosis of delayed radiation injury (eg, mandibular osteoradionecrosis, hemorrhagic radiation cystitis, radiation proctitis, or soft tissue radionecrosis) consistent with ECHM/UHMS guidance; 2) Multidisciplinary assessment completed and HBOT used as an adjunct to other appropriate interventions; 3) HBOT protocol consistent with guideline ranges (commonly 30–60 sessions at 2.0–2.5 ATA for 90–120 minutes per session) with anticipated course and follow-up documented.guideline-concordant course length (30–60 sessions)

Systematic reviews and ECHM/UHMS guidance support HBOT for selected LRTI manifestations

HBOT for Idiopathic Sudden Sensorineural Hearing Loss

Covered when ALL of the following are met (ISSHL):

ISSHL HBOT coverage: 1) Diagnosis of idiopathic sudden sensorineural hearing loss confirmed by audiometry; 2) Presentation within 14 days (preferably within 2 weeks) of symptom onset for initial therapy (or within 1 month for salvage adjunctive therapy) AND documentation of time since onset; 3) Concurrent systemic corticosteroid therapy (or documented reason for combination therapy); 4) Degree of hearing loss moderate to profound (eg, ≥40 dB) or clinical scenario matching guideline recommendations.time from onset (≤14 days preferred) and hearing loss severity (≥40 dB)

AAO-HNS, ECHM, and UHMS recommend HBOT as adjunct to steroids within recommended time windows; evidence shows greater benefit when used early and in more severe losses

Guideline-supported indications

Covered when ALL of the following apply for each indication supported by evidence or society guidance:

SSNHL: Idiopathic sudden sensorineural hearing loss (ISSHL) with moderate to profound loss (≥40 dB) who present within 14 days of symptom onset; HBOT is provided as an adjunct to medical therapy per society guidance.presentation within 14 days

UHMS and ECHM recommend HBOT in specified SSNHL scenarios

Intracranial abscess: Adjunctive HBOT for intracranial abscess when one or more conditions are present: multiple abscesses; deep or dominant location; compromised host; contraindication to surgery; lack of response or further deterioration with standard therapy — multidisciplinary review and documentation required.case-by-case multidisciplinary determination

ECHM and UHMS endorse adjunct HBOT in selected intracranial abscess cases

Necrotizing infections (NSTI/Fournier): Adjunctive HBOT for necrotizing soft tissue infections, including Fournier gangrene, particularly in compromised hosts or refractory cases; HBOT is used alongside urgent surgical debridement and antibiotics and should not delay standard emergent care.used with standard surgical and antibiotic care

Systematic reviews and society guidance report reduced mortality in pooled analyses though evidence is mainly retrospective

Burns: Adjunctive HBOT for thermal burns meeting criteria (eg, ≥20% total body surface area or burns to hands, face, feet, or perineum) when provided at specialized centers and used as an adjunct to standard burn care to preserve marginal tissue and reduce edema.burn size/location criteria

ECHM and UHMS recommend HBOT in defined burn populations

Insufficient evidence / investigational

Not covered or considered investigational unless within a clinical trial or specific documented exception:

Mild HBOT (mHBOT): Use of mild hyperbaric oxygen therapy delivered in low‑pressure fabric chambers that do not reach therapeutic pressures (<1.4 ATA while the patient breathes air) is not supported by evidence and is considered not medically necessary.does not achieve therapeutic pressure/oxygenation

mHBOT lacks demonstrated biologic benefit and has regulatory/safety concerns; FDA clearance for these devices is limited to acute mountain sickness

Topical Oxygen Therapy (TOT): Topical oxygen therapy lacks robust, high-quality evidence for routine clinical use; TOT is considered investigational or not medically necessary for routine treatment of wounds and ulcers outside of clinical trials or well-documented exceptions.insufficient peer-reviewed evidence

Systematic reviews show heterogeneous results and professional societies (UHMS) do not recommend routine application

Adjunctive TOT (contextual criteria)

TOT may be considered as adjunctive therapy when ALL of the following contextual conditions are met:

Adjunctive TOT candidate: Standard of care (debridement, off-loading, moist wound care, infection control) has been provided and failed to achieve healing or substantial improvement.

IWGDF issues a conditional recommendation for TOT as adjunct when standard care has failed

Appropriate wound types: Wounds under consideration are chronic wounds (eg, diabetic foot ulcers) or wounds with vascular compromise where RCT evidence for TOT exists or is most applicable.

Most RCT evidence evaluates DFUs; evidence for other wound types is weaker or heterogeneous

Resource and monitoring capability: Facility has capability to deliver and monitor TOT with documentation of wound size, depth, healing trajectory, adverse events, and planned follow-up, and the intervention is part of a structured treatment pathway or trial.

Professional groups emphasize need for appropriate resources and further scientific scrutiny before routine adoption

Mild hyperbaric oxygen therapy (mHBOT) devices — commonly low‑pressure fabric chambers that operate below 1.4 ATA while the patient breathes air — do not meet the policy definition of Hyperbaric Oxygen Therapy. The available literature consists largely of animal studies, small uncontrolled series, and anecdotal reports and shows that mHBOT does not reliably increase tissue oxygenation to therapeutic levels; therefore use of these devices is considered not medically necessary for any indication.

Evidence and society guidance support HBOT for avascular necrosis of the femoral head primarily in early or precollapse disease (Ficat I–II, early III). Use of HBOT outside those studied stages or in populations not represented in the clinical series (for example, advanced Ficat stages) lacks supporting data and would be inconsistent with the populations evaluated in available studies; such use is therefore not supported by this policy.

Systematic assessment by ECRI concluded that current clinical evidence for HBOT to improve outcomes for compromised skin grafts and flaps is insufficient and of low quality. Because the evidence base is not robust, routine coverage for graft or flap salvage with HBOT cannot be assumed without compelling, individualized clinical justification and supporting documentation.

UHMS guidance and the trial evidence for diabetic foot ulcers (DFUs) indicate that benefit from adjunctive HBOT is concentrated in more severe ulcers (Wagner grade ≥3) or after failure of an adequate trial of conservative care. Trials often show short‑term improvements in healing that are not consistently sustained long term; therefore UHMS recommends selecting DFU patients by Wagner grade and prior treatment response when considering HBOT.

Pressure chambers that fail to meet recognized EU/industry safety standards or low‑pressure fabric chambers providing mHBOT raise safety and regulatory concerns and do not comply with professional society recommendations. Use of such noncompliant devices is discouraged because they do not satisfy accepted manufacturing, safety, or evidence standards.

Treatments delivered in mHBOT devices that provide pressures below 1.4 ATA while the patient breathes air do not meet the Undersea and Hyperbaric Medical Society definition of therapeutic HBOT. Such exposures are not considered equivalent to standard HBOT and are not regarded as therapeutic in this policy.

Coverage specifics, prior authorization requirements, and any limits applicable to HBOT, mHBOT, or topical oxygen therapy are governed by the member specific benefit plan document; when plan terms differ from this policy, the member specific benefit plan document controls.

HBOT is considered unproven and not medically necessary for any indication not explicitly listed as medically necessary in this policy.

Routine HBOT for carbon monoxide poisoning in patients who do not have symptomatic, neurologic, cardiac, pregnancy, or other high‑risk features is not supported by consistent randomized trial evidence demonstrating improved mortality or neurologic outcomes and therefore is not routinely indicated.

Routine application of HBOT for compromised skin grafts and flaps lacks consistent, high‑quality evidence; ECRI judged existing studies insufficient to determine efficacy, so routine coverage is not supported without stronger data or specific clinical justification.

The UHMS does not suggest HBOT for Wagner grade 2 or lower diabetic foot ulcers. Adjunctive HBOT for DFUs is supported primarily for Wagner grade ≥3 ulcers or after failure of adequate conservative therapy; HBOT for Wagner grade ≤2 or without documented prior conservative therapy failure is not supported by guideline recommendations or trial evidence.

Routine use of mild HBOT (mHBOT) or topical oxygen therapy (TOT) as standard treatment for wounds or other conditions is not medically necessary given the current limited and inconsistent evidence. Professional societies (UHMS, ECHM) and systematic reviews caution that TOT and mHBOT lack robust RCT support and should not be recommended as routine therapy.

Because randomized trial evidence and systematic reviews for topical oxygen therapy remain limited and heterogeneous, routine application of TOT or mHBOT cannot be recommended as standard clinical treatment. These modalities may be considered investigational or only as adjuncts within defined clinical protocols or trials with appropriate documentation and monitoring.

Procedure, Supply and Device Codes

Applicable Procedure and Supply Codesmixed

99183	Physician or other qualified health care professional attendance and supervision of hyperbaric oxygen therapy, per session
G0277	Hyperbaric oxygen under pressure, full body chamber, per 30 minute interval
A4575	Topical hyperbaric oxygen chamber, disposable
E0446	Topical oxygen delivery system, not otherwise specified, includes all supplies and accessories

No explicit CPT/HCPCS/ICD-10 codes listed in this document portionmixed

No codes listed

Covered / recommended indications (guideline-based)mixed

No codes listed

Clinical indications and guideline references (no explicit billing codes in this segment)mixed

No codes listed

Device product codes referencedmixed

CBF	FDA product code for hyperbaric chamber

Device product codes referencedmixed

KPJ	FDA product code for topical oxygen therapy devices

HBOT pressure threshold

Minimum pressure to qualify as HBOT>= 1.4 ATA (patient breathes near 100% oxygen at or above this pressure)

Definition source wordingHBOT: breathing near 100% oxygen intermittently inside a chamber pressurized to equal or exceed 1.4 ATA.

Mild/low-pressure distinctionExposures <1.4 ATA (mHBOT) do not meet the definition of therapeutic HBOT per UHMS/ECHM guidance.

HBOT sessions for radiation injury

Typical course length for delayed radiation injury30–60 HBOT sessions

Session frequency contextCourses usually delivered daily with protocol parameters guided by UHMS/ECHM recommendations.

Associated single-session duration (context)Typical single-session durations cited for radiation injury are 90–120 minutes at guideline pressures.

HBOT pressure used in RCT for graft uptake

RCT pressure range for graft uptake1.5–2.0 ATA (daily sessions reported in RCT evaluating split-thickness graft uptake)

Session duration in RCT90 minutes per session as used in the published RCT protocol

Timing of initiation in RCTHBOT began early postoperatively (e.g., postoperative day 2 in the referenced trial)

ECHM suggested pressure for grafts/flaps

ECHM recommended pressure for grafts/flaps203–253 kilopascals (~2.03–2.53 ATA) per session

Minimum suggested session durationAt least 60 minutes per session (ECHM recommendation)

Suggested initial frequencyRepeat 2–3 times on day 1, then once or twice daily until tissue viability is declared

ISSHL severity threshold

ISSHL hearing loss severity threshold for HBOT consideration≥ 40 dB (moderate to profound sensorineural hearing loss)

Evidence basisUHMS includes SSNHL as a recommended indication for patients with moderate to profound loss (≥40 dB)

Audiometry requirementDocument degree and frequencies of hearing loss by audiometry when requesting HBOT

SSNHL timing

Preferred initiation window for ISSHL HBOTInitiate HBOT within 14 days of symptom onset (best evidence within 2 weeks)

Salvage window guidanceECHM allows consideration up to 1 month for salvage therapy in severe cases when combined with corticosteroids

Documentation neededRecord time since symptom onset and concurrent steroid therapy per authorization requirements

Burns

Burn patient selection for adjunctive HBOTRecommended for thermal burns ≥20% total body surface area or burns involving hands, face, feet, or perineum

Treatment contextHBOT should be provided as an adjunct at specialized centers in the immediate vicinity of a burn center and not to delay standard burn care

Therapeutic goalsAimed at minimizing edema, preserving marginal tissue, protecting microvasculature, and promoting wound closure

Provider Actions and Prior Authorization Guidance

Prior Authorization

Confirm prior authorization and benefit alignment

Provider should confirm prior authorization requirements with the member’s benefit plan before scheduling HBOT or topical oxygen services. Listing of procedure or diagnosis codes in this policy does not guarantee coverage or payment — providers must verify plan rules, benefit limits, and any federal or state mandates that may apply.

Verify member-specific prior authorization and benefit coverage before initiating treatment.
Check for Medicare NCD/LCD or state/federal mandates that may supersede plan rules.

Prior Authorization

Indication- and stage-specific prior authorization

Prior authorization should be indication- and stage-specific. Requests must tie the clinical justification to the guideline-supported disease stage or timing window (for example: Ficat staging for avascular necrosis, Wagner grade and prior weeks of wound care for DFU, or time-from-onset for ISSHL). Requests outside guideline-supported stages or in contraindicated patients risk denial.

Include disease stage (e.g., Ficat I–III; Wagner grade; ISSHL dB severity) and rationale for HBOT at that stage.
Document why HBOT is being sought outside typical guideline windows, if applicable.

Prior Authorization

Authorization requires indication and planned regimen

Authorization requires documentation of the clinical indication and the planned HBOT or topical oxygen regimen. The request should specify the intended pressure, duration per session, frequency, and total planned number of sessions (or planned TOT delivery parameters).

For HBOT, document target ATA (must meet therapeutic definition ≥1.4 ATA), minutes per session, and planned number of sessions (e.g., 30–60 sessions for radiation injury; 60 sessions for refractory osteomyelitis when indicated).
For TOT, state device type (e.g., continuous diffusion of oxygen), session length or continuous delivery plan, and wound dressing removal during application.

Prior Authorization

Prior authorization for guideline-supported indications

When requesting HBOT for indications that are supported by specialty society guidelines (UHMS, ECHM, AAO-HNS, SVS/APMA/SVM, IWGDF, etc.), include citation(s) and documentation that the case meets society-recommended criteria (for example, DFU after ≥4 weeks of standard care or ISSHL within 14 days). Prior authorization is recommended for guideline-supported indications to confirm medical necessity under the member plan.

Attach relevant guideline statements and patient-specific evidence (timing, stage, prior therapy).
Examples: DFU — failed ≥4 weeks standard wound therapy with <50% area reduction; ISSHL — presentation within 14 days and audiometry showing ≥40 dB loss.

Prior Authorization

Prior authorization: adjunctive topical oxygen for DFUs

Topical oxygen therapy (TOT) used as an adjunct for diabetic foot ulcers may require prior authorization. Clinical statements vary — when requesting payment for adjunctive TOT include documentation of prior standard care, clinical rationale for adjunctive TOT, and local guideline support if present.

Document prior conservative therapy for DFU and why TOT is being used as adjunctive care.
If using continuous or device-specific TOT, specify device make/model, treatment parameters, and wound response monitoring plan.

Prior Authorization

Verify prior authorization before treatment

Providers must verify that required prior authorizations have been obtained and remain valid for the dates of service. Failure to obtain required authorization may result in claim denial or member liability.

Confirm authorization number and valid service dates before treatment.
Re-verify when treatment plans change (additional sessions, different indication).

Billing Rule

Coding inclusion is not a guarantee of coverage

Coding inclusion in this policy is for reference only and does not ensure coverage or reimbursement. Always cross-check coding with the payer’s current billing guidelines and the member’s benefit plan.

The presence of procedure codes (e.g., 99183, G0277, A4575, E0446) in this policy does not imply coverage.
Use member-specific benefit and billing rules to determine reimbursable codes.

Denial Risk

Stage and contraindication mismatch may lead to denial

Requests that seek HBOT for stages or clinical scenarios outside the evidence base or in patients with contraindications (eg, untreated pneumothorax, certain severe cardiopulmonary instability) may be denied. Explicitly document contraindications considered and rationale when treating higher-risk patients.

List any contraindications assessed and why therapy is still being considered, if applicable.
If treating outside studied stages, provide supporting literature and multidisciplinary rationale.

Denial Risk

Evidence limitations may trigger additional review

Evidence limitations for certain indications (for example, skin grafts/flaps, some burn indications, or mHBOT) may necessitate additional clinical review. When the evidence base is limited, include multidisciplinary consult notes and prior therapeutic attempts to support medical necessity.

For compromised grafts/flaps, include surgical notes, timing of HBOT relative to surgery, and graft viability assessments.
Expect peer review or requests for supplemental evidence when literature is sparse.

Denial Risk

Risk of denial for mild HBOT / low-pressure chambers

Services delivered with mild HBOT or low-pressure chambers that do not reach therapeutic pressures (<1.4 ATA) are at high risk for denial. mHBOT does not meet the definition of therapeutic HBOT and lacks evidence of clinical benefit for approved indications.

Do not submit claims for therapeutic HBOT for sessions delivered at <1.4 ATA.
If a facility uses mHBOT devices, clearly document the device pressure and regulatory clearance; expect denials for therapeutic indications.

Denial Risk

Mild HBOT pressure insufficiency: documentation and billing warning

mHBOT devices operating below 1.4 ATA and delivering air (not near 100% oxygen at pressure) do not meet the UHMS definition of therapeutic HBOT and are not appropriate for UHMS-approved indications.

When pressure <1.4 ATA, label as mild HBOT and verify device labeling/indications (typically cleared only for altitude sickness).
Avoid conflating mHBOT sessions with therapeutic HBOT on prior authorization requests.

Prior Authorization

Benefit-plan alignment required

Benefit-plan alignment is required. Even if the clinical criteria are met, coverage decisions are governed by the member-specific benefit plan and any applicable mandates. Confirm plan benefits, medical necessity rules, and prior authorization pathways.

If a conflict exists between this policy and the member’s plan document, the plan document governs.
Verify any state or federal mandates that may affect coverage (for example, state-mandated benefits).

Documentation Required

Treatment delivery requirements

Treatment delivery requirements: for effective topical oxygen application, remove wound dressings during application when applicable; for HBOT, ensure chamber type, pressure, oxygen delivery method, and session timings align with therapeutic definitions and the authorized regimen.

TOT: remove dressings during enclosed topical application unless using cannula-under-dressing continuous systems; document dressing removal in notes.
HBOT: ensure session parameters meet the authorized ATA and duration; document chamber class (A or B) and oxygen delivery method.

Documentation Required

Required clinical documentation (general)

Required clinical documentation for prior authorization should support the indication and planned course. Include relevant imaging, laboratory results, staging/grading, prior treatments and dates, and multidisciplinary consults when applicable.

Imaging: radiographs/MRI for AVN staging; wound photographs and measurements for DFU; audiometry for ISSHL; brain imaging for intracranial abscess.
Prior therapies: antibiotics, debridement, revascularization, standard wound care with dates and quantitative response (percent wound area change over prior 4 weeks).

Documentation Required

Support clinical indication and intended HBOT course

Support the clinical indication and intended HBOT course by providing a treatment plan that includes goals, expected response timepoints, and planned reassessment intervals.

State therapeutic goals (eg, reduce risk of major amputation, improve graft uptake, radiologic resolution of abscess).
Specify reassessment plan (eg, wound area % change at 4 weeks, audiometry at 2 weeks).

Documentation Required

Required clinical documentation for DFU HBOT

Required documentation for DFU HBOT prior authorization: include wound stage/grade (Wagner), perfusion assessment, at least 4 weeks of documented standard wound therapy with objective wound measurements showing inadequate healing (eg, <50% area reduction), and prior revascularization or infection management when relevant.

Document baseline and interval wound measurements (planimetry or photos) and percent area change over the prior 4 weeks.
If post-debridement or post-surgical, include operative notes and timing relative to HBOT request.

Documentation Required

Required clinical documentation for ISSHL HBOT

Required documentation for ISSHL (sudden sensorineural hearing loss) HBOT: clearly document time from symptom onset to presentation, baseline and interval audiometry results (dB, pure tone average), concurrent steroid therapy, and clinical rationale for HBOT.

Include audiogram showing degree of hearing loss (eg, ≥40 dB for moderate-to-profound) and symptom onset date.
Document combined steroid therapy plan and whether HBOT is initial or salvage therapy (within 2 weeks preferred; salvage within 1 month supported by some guidance).

Documentation Required

Documentation for intracranial abscess HBOT

Documentation for intracranial abscess HBOT requests should describe the abscess characteristics (number, size, location), prior and concurrent antimicrobial therapy, any surgical interventions (aspiration, drainage), and multidisciplinary consultation (neurosurgery, infectious disease). Provide rationale for adjunctive HBOT (eg, deep-seated or multiple abscesses, poor response to standard therapy).

Include serial imaging reports and timelines of response to antibiotics and surgery.
Attach notes from interdisciplinary case review supporting HBOT as adjunctive therapy.

Documentation Required

Suggested clinical documentation elements

Suggested clinical documentation elements to include in all HBOT/TOT prior authorization requests: patient selection criteria, wound/lesion characteristics, objective baseline measures, details of prior and concurrent therapies, anticipated number of sessions, adherence plan, and planned outcome timepoints for reassessment.

Baseline measures: wound area, depth, infection markers, imaging, audiometry as applicable.
Monitoring plan: schedule for reassessment and criteria for continuation or discontinuation.

Prior Authorization

Plan and mandate verification

Plan and mandate documentation: always reference the member-specific benefit plan and document that any required state or federal mandates were checked and addressed. In case of conflict between this policy and the member plan, the member plan governs.

Document verification of member benefits and any mandate assessments in the authorization request.
If Medicare Advantage, note absence/presence of NCD/LCD and cite MAO policy rationale if used.

Step Therapy

Adjunctive use after standard therapy (infections and other indications)

Adjunctive HBOT after standard therapies: For infection indications (chronic osteomyelitis, necrotizing infections, intracranial abscess), HBOT is generally positioned as an adjunct after appropriate antibiotics and surgical source control. Document prior antibiotic regimens, surgical debridement details, and timing relative to HBOT initiation.

For chronic osteomyelitis, include culture results, debridement operative reports, and antibiotic course details.
For necrotizing infections and intracranial abscess, document concurrent surgical and antibiotic therapy and multidisciplinary decision-making.

Step Therapy

Step therapy sequencing and stepwise positioning

Step therapy sequencing for DFU and stepwise therapy positioning: HBOT and TOT are adjunctive options after failure of standard-of-care management. For DFU, prior conservative care of at least 4 weeks (often 4–6 weeks) with documented inadequate response is expected before considering HBOT. Position HBOT/TOT in the care pathway accordingly and document prior steps.

Document specific prior therapies and objective response thresholds (eg, <50% wound area reduction after ≥4 weeks).
Do not use HBOT/TOT as first-line therapy for DFU unless exceptional circumstances are justified and documented.

Background and Rationale

Hyperbaric oxygen therapy delivers near‑100% oxygen intermittently while the patient is inside a pressurized chamber and, to meet the clinical definition of HBOT, the treatment pressure should equal or exceed 1.4 ATA. HBOT is used either as a primary therapy or as an adjunct to surgical or pharmacologic care for selected indications and is typically delivered under protocolized pressures and durations supported by specialty guidance.

Definitions and Key Terms

Hyperbaric Oxygen Therapy definition

Core definition of HBOTBreathing near 100% oxygen intermittently inside a chamber pressurized to ≥1.4 ATA.

Delivery systemsCan be delivered in class A (multiplace) or class B (monoplace) chambers; class B chambers pressurize the chamber with near 100% oxygen in monoplace setups.

Clinical roleUsed as primary therapy in some conditions and as an adjunct to surgical or pharmacologic interventions in others (per UHMS/ECHM).

Mild Hyperbaric Oxygen Therapy

Definition of mild HBOT (mHBOT)Low-pressure fabric or semirigid chambers delivering pressures <1.4 ATA; these exposures do not achieve therapeutic tissue oxygenation.

Regulatory clearance noteDevices of this type have FDA 510(k) clearance only for acute mountain sickness; not supported for other therapeutic claims per UHMS/AMA concerns.

Evidence limitationsAvailable data are limited to small uncontrolled studies and animal reports; mHBOT has not demonstrated benefits beyond placebo in reviewed literature.

Topical Oxygen Therapy

Topical Oxygen Therapy (TOT) descriptionDirect application of oxygen to a wound site via a sealed enclosure placed over the wound or continuous delivery through a cannula under a dressing.

Delivery modesCan be administered intermittently at slightly above atmospheric pressure (sealed enclosure) or continuously via a cannula beneath occlusive dressing (CDO systems).

Evidence and regulationPeer-reviewed evidence is limited; devices are regulated by FDA as Class II (product code KPJ) though clinical effectiveness remains inconclusive.

Early-stage femoral head necrosis (Ficat I–II / early III)

Staging required for early femoral head necrosisEarly-stage FHN (Ficat I–II) or precollapse early Ficat III should be confirmed radiographically (radiograph or MRI) prior to HBOT consideration.

Guideline contextECHM and UHMS recommend HBOT in these early/precollapse stages as part of a multidisciplinary plan.

Authorization implicationAuthorization should document disease stage (Ficat classification) and imaging confirmation per policy requirements.

Time window for central retinal artery occlusion

Time-sensitive window for CRAO HBOTConsider HBOT for patients presenting within 24 hours of symptom onset; initial treatment may be a 90-minute session with repeat treatments guided by response.

Triage urgencyPatients with sudden painless vision loss from CRAO should be triaged as emergent due to need for immediate oxygen therapy.

Treatment variabilityOptimum number of treatments varies with severity and response; U.S. Navy Table Six may be used for first treatment in some protocols.

Refractory osteomyelitis

Definition of refractory osteomyelitisOsteomyelitis that persists despite culture-directed antibiotics and, when applicable, surgical debridement; HBOT is considered an adjunct in such cases.

Recommended course before assessing effectECHM suggests approximately 60 sessions over 11–12 weeks before expecting significant clinical effect.

Combination therapy expectationHighest reported cure rates observed when HBOT is combined with antibiotics and concurrent surgical debridement (UHMS/ECHM guidance).

Delayed radiation injury (LRTI)

Delayed radiation injury (LRTI) definitionRadiation-induced soft tissue or bony necrosis occurring after radiotherapy, often managed with multidisciplinary care and adjunctive HBOT.

Typical management contextMultidisciplinary assessment with HBOT courses commonly in the range of 30–60 treatments at 2.0–2.5 ATA for 90–120 minutes per session.

Indications includedIncludes mandibular osteoradionecrosis, hemorrhagic cystitis, proctitis, and soft tissue radionecrosis per ECHM/UHMS guidance.

HBOT protocol parameters

Typical HBOT protocol parametersCommon protocols: 2.0–2.5 ATA for 90–120 minutes per session; overall courses often range 30–60 sessions depending on indication.

Session frequencyDaily treatments are typical; some indications or institutional protocols may allow twice-daily treatments early in a course.

Course duration guidanceEvaluate effects repeatedly during and after treatment; some indications (e.g., refractory osteomyelitis) may require ~60 sessions over 11–12 weeks.

Wagner grade 2-4 DFU

Wagner grade 2–4 DFU definition used for HBOT evidenceDiabetic foot ulcers classified as Wagner grades 2–4 (partial to full-thickness ulcers with varying depth, infection, or necrosis) where adjunctive HBOT has supporting evidence.

Evidence summarySystematic reviews and RCTs included patients with ulcers unresponsive after ≥30 days of standard care; moderate-quality evidence supports improved healing and reduced amputations for grades 2–4.

Authorization documentationDocument prior standard wound care, percent wound area reduction over preceding 4 weeks, Wagner grade, and perfusion assessment when requesting HBOT.

mild hyperbaric oxygen therapy (mHBOT)

mHBOT definition and pressure threshold notemHBOT refers to treatments delivered in low-pressure fabric/semirigid chambers operating at pressures <1.4 ATA while the patient breathes air and thus do not meet the definition of therapeutic HBOT.

Regulatory and safety concernsUHMS and AMA have expressed concerns regarding facilities offering mHBOT; FDA clearance for such devices typically limited to acute mountain sickness.

Evidence limitationsBenefits are derived from animal studies, small uncontrolled studies, and anecdote; mHBOT does not reliably increase tissue oxygenation to therapeutic levels.

Topical oxygen therapy (TOT)

TOT definition and delivery modesTopical oxygen therapy: device-delivered oxygen applied directly to a wound either intermittently within a sealed enclosure or continuously via a cannula under an occlusive dressing (CDO).

Evidence limitation notePeer-reviewed evidence evaluating TOT is limited; systematic reviews call for more robust RCTs and long-term outcome data before routine endorsement.

Regulatory statusTOT devices are regulated by the FDA as Class II devices (product code KPJ) though regulation does not imply proven clinical effectiveness.

mHBOT (alternate inventory entry)

Alternate mHBOT entry (device description)Low-pressure fabric or semirigid chambers that operate below 1.4 ATA while the patient breathes air; intended for mild compression and altitude sickness indications rather than therapeutic HBOT.

Clinical implicationSuch devices do not achieve minimum pressures/oxygen levels required for UHMS-approved indications and are not recommended for routine therapeutic use.

Authorization riskUse of these devices may be at risk for coverage denial due to failure to meet HBOT definition and evidence standards.

Topical oxygen therapy (device-regulatory note)

TOT device regulatory noteTopical oxygen therapy devices are regulated by the FDA as Class II devices (product code KPJ); several devices have been cleared via 510(k).

FDA classification for hyperbaric chambersHyperbaric oxygen chambers are Class II devices (product code CBF); some low-pressure semirigid chambers are cleared for acute mountain sickness.

Regulatory cautionFDA clearance or classification does not itself establish clinical effectiveness for broad therapeutic indications; clinical evidence remains limited for TOT.

UHMS indications

UHMS compiled indications referenceUHMS indications are compiled in the UHMS manual and position statements (15th edition) and list multiple accepted HBOT indications (e.g., LRTI, ISSHL, NSTI).

Use in policy contextPolicy references UHMS guidance (2019, updated 2023) for many coverage decisions and parameter recommendations.

Availability of full guidanceFull UHMS indications manual and related position statements are cited for clinical detail and recommended protocols.