UnitedHealthcare HBOT Coverage Update

Medically Necessary Indications for HBOT

HBOT is medically necessary when the listed diagnosis is present.

Listed 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, or 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)

List taken verbatim from policy

Unproven and Not Medically Necessary

Not medically necessary / Unproven

Unproven Therapies: Topical Oxygen Therapy for treatment of wounds or ulcers is unproven and not medically necessary due to insufficient evidence; Mild (low‑pressure) Hyperbaric Oxygen Therapy is unproven and not medically necessary for any indication because it does not meet the therapeutic pressure definition for HBOT.

Policy explicitly states both are not medically necessary

Avascular necrosis (early stages) — evidence summary

HBOT has evidence of benefit in early-stage femoral head necrosis; study-level summaries follow.

Avascular Necrosis (Ficat I-II): Cohort studies and a meta-analysis report clinical improvement (pain, function, MRI changes) with HBOT in early-stage femoral head necrosis; some comparative cohort data suggest equal or greater benefit when HBOT is combined with core decompression.Ficat stage I-II (precollapse)

Evidence primarily observational; authors call for larger RCTs

Carbon monoxide poisoning — evidence and guideline guidance

Randomized trials and systematic reviews provide mixed evidence for HBOT in acute carbon monoxide poisoning; guideline guidance is summarized below.

Carbon monoxide poisoning: Systematic reviews of RCTs show inconsistent results for mortality and neurocognitive outcomes; some trials and meta-analyses report reduced neuropsychological sequelae with HBOT. Guideline bodies (ACEP, ECHM, UHMS) recommend selective use—consider HBOT for symptomatic patients, pregnant women, and those with neurologic or cardiac signs—and emphasize early treatment when used.treatment selection and timing dependent

Evidence quality rated low to very low; recommendations vary by society

Central retinal artery occlusion — timing-sensitive therapy

HBOT may improve visual outcomes when delivered early for central retinal artery occlusion.

Central retinal artery occlusion: Meta-analyses and guideline statements report improved best-corrected visual acuity with HBOT, particularly when administered emergently (patients presenting within 24 hours) and with extended oxygen exposure; UHMS recommends emergent triage and consideration of HBOT within 24 hours.presentation within 24 hours; extended initial oxygen exposure often reported

Evidence from small trials and observational studies; adverse events infrequent

Chronic refractory osteomyelitis — adjunctive HBOT

HBOT used as an adjunct to antibiotics and surgical debridement has been associated with high remission rates in refractory chronic osteomyelitis.

Refractory chronic osteomyelitis: Systematic reviews and cohort studies report favorable outcomes when HBOT is combined with culture-directed antibiotics and adequate surgical debridement; reported remission/success rates are high in observational series.Adjunctive to antibiotics and surgery; extended multi‑week course often required (~60 sessions)

ECHM suggests ~60 sessions over 11–12 weeks; evidence primarily observational with heterogeneity

Guideline-supported Indications

Covered when ALL of the following are met (for guideline-supported indications):

Core requirements: 1) Indication is supported by UHMS/ECHM guidance (examples include refractory osteomyelitis, gas gangrene, decompression sickness, compromised grafts/flaps, delayed radiation injury), AND 2) HBOT is provided as an adjunct to appropriate standard therapies when relevant (e.g., culture-directed antibiotics, surgery), AND 3) A documented treatment plan specifies typical HBOT parameters (pressure, session duration, and number of sessions) and prior/concurrent therapies.

Supported by UHMS and ECHM recommendations

Delayed Radiation Injury

Covered when ALL of the following are met

Radiation injury criteria: Patient has late radiation-induced tissue toxicity (e.g., osteoradionecrosis, hemorrhagic radiation cystitis/proctitis, soft tissue radionecrosis) AND prior/concurrent multidisciplinary care is documented AND HBOT is delivered per an appropriate course (commonly 30–60 sessions at approximately 2.0–2.5 ATA for 90–120 minutes) or per specialist recommendation.typical course: 30–60 treatments; pressure: ~2.0–2.5 ATA; duration: 90–120 minutes per session

Systematic reviews and society guidance report benefit for many LRTI manifestations

Initial coverage criteria for HBOT (DFU, radiation injury, ISSNHL)

Covered when ALL of the following are met (DFU/adapted guidance from multiple organizations):

DFU_HBOT_initial_criteria

Wagner_grade: Wagner grade 2 to 4 considered; UHMS specifically recommends for grade >=3Wagner grade 2–4 (evidence strongest for 2–4); UHMS: grade >=3
Systematic reviews report improved healing and reduced major amputations for grades 2–4

Radiation_injury_HBOT: Delayed radiation-induced soft tissue or bony necrosis or specified radiation injuries (e.g., mandibular osteoradionecrosis, hemorrhagic radiation cystitis/proctitis)treatment courses commonly 30–60 sessions at 2.0–2.5 ATA for 90–120 minutes

ECHM and UHMS recommend HBOT for these radiation injuries

Guideline-supported HBOT indications (narrative)

Covered when supportive guideline criteria are met (as summarized):

ISSHL: ECHM and UHMS recommend HBOT as an adjunct to medical therapy for idiopathic sudden sensorineural hearing loss when patients present within 2 weeks of onset (ECHM) or within 14 days for moderate to profound loss (>=40 dB) (UHMS); ECHM allows use up to 1 month in select severe cases.presentation within 14 days; UHMS threshold >=40 dB

Early intervention associated with improved outcomes

Intracranial abscess: ECHM and UHMS recommend adjunct HBOT for intracranial abscess in selected situations (multiple abscesses, deep location, compromised host, contraindication to surgery, lack of response to standard care); decisions are case-by-case with multidisciplinary input.case-by-case multidisciplinary decision

Evidence primarily retrospective cohorts and small series

Necrotizing soft tissue infections (NSTI)/Fournier gangrene:

TOT adjunctive coverage considerations

TOT as adjunct to standard care may be considered when the following contextual conditions are met (reflecting guideline and trial contexts):

TOT adjunctive consideration: 1) Standard of care for diabetic foot ulcers has been provided and has failed or is insufficient; 2) Resources and capability exist to support TOT application; 3) Patient selection aligns with trial inclusion characteristics (e.g., chronic wound duration >4 weeks and wound size/depth consistent with study ranges); 4) No active infection requiring alternative interventions or other contraindications per trial and guideline criteria.

Derived from IWGDF conditional recommendation and trial inclusion/exclusion contexts

HBOT device/pressure requirement

HBOT coverage consideration relevant to device/pressure:

Therapeutic HBOT pressure requirement: Device must deliver therapeutic pressures consistent with UHMS-defined HBOT (pressure must equal or exceed 1.4 ATA while breathing near 100% oxygen). Low-pressure/mild hyperbaric chambers that provide <1.4 ATA while the patient breathes air (mHBOT) do not meet the definition of therapeutic HBOT and are not acceptable substitutes.>= 1.4 ATA required; <1.4 ATA not acceptable

UHMS position statement; policy definition of HBOT

Mild Hyperbaric Oxygen Therapy (mHBOT) and Topical Oxygen Therapy (TOT) are excluded from the list of medically necessary HBOT indications. The policy states that mHBOT devices operate at pressures <1.4 ATA and do not meet the clinical definition of therapeutic HBOT, and that conclusions supporting mHBOT are limited to animal data, small uncontrolled studies, and anecdote rather than robust clinical evidence. Similarly, TOT lacks sufficient high-quality evidence to be considered medically necessary for treatment of wounds or ulcers and is explicitly described as unproven and not medically necessary for those indications.

Providers billing for HBOT should ensure the device and delivered treatment meet the therapeutic HBOT definition (pressure ≥ 1.4 ATA) and that topical oxygen or mild HBOT are not billed as equivalent therapeutic HBOT interventions.

Evidence for several HBOT indications is heterogeneous and limited by study design, small sample sizes, and variable protocols. Systematic reviews and randomized trials for conditions such as carbon monoxide poisoning and diabetic foot ulcers have produced mixed findings, with short‑term benefits sometimes reported but long‑term outcomes and consistent mortality or neurologic improvements not established. The policy emphasizes these limitations and the need for higher-quality, multicenter randomized controlled trials to clarify benefit in many settings.

When evidence is inconsistent or of low quality, the policy directs case selection, thorough documentation of prior/concurrent treatments, and caution in extrapolating trial results to routine practice.

Some clinical contexts—specifically compromised skin grafts and flaps—have insufficient high‑quality evidence to definitively establish HBOT benefit. An ECRI assessment concluded current clinical evidence is too limited to determine effectiveness for graft or flap salvage, and available observational reports are mixed. While professional guidance (ECHM, UHMS) suggests HBOT can be considered in flap/graft salvage, the policy notes that stronger randomized data are lacking and additional justification and documentation may be required when HBOT is requested for these indications.

Providers should document timing, severity, prior surgical and medical management, and objective measures of tissue viability when seeking coverage for HBOT in compromised grafts or flaps.

Guidance from the Undersea and Hyperbaric Medical Society (UHMS) is cited for diabetic foot ulcers (DFUs). UHMS recommends HBOT for Wagner grade 3 or higher DFUs that have not responded to at least 30 days of standard wound care, and supports postoperative HBOT after surgical debridement to reduce major amputation risk in selected patients. However, systematic reviews and randomized trials show benefit at short‑term endpoints (e.g., healing at 6 weeks) but not consistently at 1 year, indicating uncertainty about sustained long‑term benefit.

The policy therefore aligns with UHMS guidance for selected DFU patients while acknowledging that long‑term benefits have not been consistently demonstrated in the literature.

The policy raises safety and regulatory concerns about mild hyperbaric oxygen therapy (mHBOT). mHBOT devices typically deliver pressures below 1.4 ATA while the patient breathes air and therefore do not meet the UHMS definition of therapeutic HBOT. Reported conclusions for mHBOT are based on low‑quality evidence (animal data, uncontrolled studies, anecdote), and there are concerns that use of these devices may delay more effective, evidence‑based therapies.

Accordingly, mHBOT is described as unproven and not medically necessary for any indication and is not an acceptable substitute for therapeutic HBOT when clinical indications and coverage criteria require UHMS‑level pressures.

The policy advises caution regarding low‑pressure chambers and topical oxygen use outside established evidence-based contexts. UHMS has stated that topical oxygen cannot be recommended for routine clinical treatment given limited and low‑quality evidence, and that low‑pressure fabric chambers producing 1.4 ATA do not achieve the pressures and oxygenation required for UHMS‑approved indications. Quality evidence for topical oxygen therapy is limited and further robust randomized trials with long‑term outcomes are needed.

Providers should not substitute topical oxygen therapy or low‑pressure mHBOT for indicated therapeutic HBOT and must document adherence to evidence‑based protocols when requesting coverage.

This policy is intended to guide coverage decisions but does not supersede the member specific benefit plan document. When there is a conflict between this policy and the member's plan terms, the member specific benefit plan document governs. Providers must verify applicable plan coverage, prior authorization requirements, and any federal or state mandates before delivering or billing for HBOT, topical oxygen, or mHBOT services.

Topical Oxygen Therapy (TOT) and mild hyperbaric oxygen therapy (mHBOT) are described in the policy as unproven and not medically necessary for treatment of wounds or for any indication, respectively, due to insufficient and low‑quality evidence of efficacy. The UHMS specifically advises that topical oxygen should not be recommended for routine clinical treatment until further scientific study establishes indications, dosing, and outcomes.

If TOT or mHBOT are proposed as adjunctive measures, documentation should demonstrate failure of standard care and alignment with trial inclusion criteria, but routine or replacement use of these modalities is not supported by current evidence.

Randomized trials and systematic reviews of HBOT for acute carbon monoxide (CO) poisoning yield inconsistent results. Several RCTs and meta‑analyses have not demonstrated a consistent benefit for mortality or long‑term neurological outcomes, and evidence quality has been rated low to very low with substantial heterogeneity across studies. Guideline organizations (ACEP, ECHM, UHMS) recommend selective use in clinically significant presentations—such as symptomatic patients, pregnant individuals, or those with neurologic or cardiac signs—but acknowledge uncertainty and call for high‑quality multicenter trials to clarify HBOT's role in CO poisoning.

Therefore, routine HBOT for CO poisoning is not uniformly supported by the evidence; selection should follow guideline‑based criteria and individualized clinical judgment.

The evidence base for HBOT in some graft and flap contexts remains insufficient. An ECRI assessment concluded the quality of evidence is too low to be conclusive for compromised skin grafts and flaps, with available studies limited by small samples and single‑center designs. Although ECHM and UHMS suggest HBOT may be used for flap salvage in specific scenarios, the policy notes these recommendations rely on limited observational data and recommends additional justification and documentation when HBOT is requested for these cases.

Providers should include objective measures of graft/flap viability, prior interventions, and clear rationale for adjunctive HBOT when seeking coverage for salvage attempts.

While HBOT shows short‑term improvements in ulcer healing for diabetic foot ulcers in several trials, long‑term benefit is not consistently demonstrated. A Cochrane review found increased healing rates at 6 weeks but no sustained benefit at 1 year, and some systematic reviews highlight heterogeneity across trials. The UHMS recommends HBOT for selected DFUs (Wagner grade ≥3) after failure of 30 days of standard care, but the policy emphasizes that trials do not consistently show durable long‑term outcomes for all DFU populations.

This inconsistency supports a careful, documented approach to HBOT for DFUs, reserving treatment for patients meeting guideline‑based selection criteria and documenting short‑term response to justify ongoing or repeat courses.

The policy lists a number of other indications for which HBOT or topical oxygen currently lack reliable, well‑designed clinical evidence and are therefore considered investigational or unproven. Examples include numerous non‑listed conditions beyond the policy's medically necessary list, and the policy highlights that topical oxygen therapy lacks sufficient peer‑reviewed evidence to support routine effectiveness claims.

Until robust randomized controlled trials provide supportive data, the routine use of topical oxygen or HBOT for unlisted indications should be considered investigational and is likely subject to denial without strong supporting documentation.

The policy discourages substituting topical oxygen or mild HBOT for therapies that meet coverage criteria for therapeutic HBOT. UHMS guidance states topical oxygen and low‑pressure mHBOT do not meet criteria to replace evidence‑based HBOT protocols; using these modalities in lieu of indicated HBOT risks delaying effective care and lacks endorsement. The policy therefore advises that topical oxygen or mHBOT should not be applied as routine alternatives to medically indicated HBOT.

When topical oxygen or mHBOT are considered, they should only be used as adjunctive measures after failure of standard care and with documentation aligning to trial or guideline contexts—not as replacements for indicated therapeutic HBOT.

Prior Authorization, Documentation, and Operational Guidance

Prior Authorization

Prior authorization: refractory osteomyelitis — adjunctive HBOT

Prior authorization is required for HBOT when used as an adjunctive therapy for refractory chronic osteomyelitis. Requests should document that the member has received appropriate prior and concurrent surgical debridement and culture-directed antibiotics, and that the case has been reviewed by a multidisciplinary team when feasible. Expected treatment course information (see below) must be provided to support medical necessity.

Document prior surgical debridement and culture-directed antibiotic therapy
Provide rationale for adjunctive HBOT and treatment goals
Include multidisciplinary consultation notes where applicable

Prior Authorization

Prior authorization for HBOT in DFUs and radiation injury

Prior authorization is required for HBOT for diabetic foot ulcers (DFUs) and for delayed/radiation injury when requested as adjunctive therapy. Requests must show that standard wound care or multidisciplinary management has failed or is inadequate, and must specify wound grade/stage, prior duration and content of conservative care, and the targeted HBOT regimen.

For DFUs: document Wagner grade, perfusion status, and at least 4 weeks (SVS) or 30 days (UHMS) of appropriate standard care with insufficient improvement
For radiation injury: document prior radiation history, site and tissue involved, prior surgical and medical management, and proposed HBOT course (typical 30–60 sessions)

Prior Authorization

Pressure/device verification prior to authorization

Prior to authorizing HBOT, verify the chamber type and treatment pressure to ensure the proposed therapy meets the definition of therapeutic HBOT (≥1.4 ATA with 100% oxygen inhalation). Mild/low-pressure chambers and nonpressurized topical devices do not meet HBOT criteria and are not eligible under therapeutic HBOT indications.

Provide device make/model and vendor documentation
Specify planned treatment pressure and oxygen delivery method (mask/hood/ET tube)
If proposing mild hyperbaric device, note that these are considered non-therapeutic and denied for HBOT indications

Prior Authorization

Verify member benefits and prior authorization

Always verify member benefits and whether prior authorization is required under the member-specific benefit plan before scheduling HBOT. Coverage decisions are governed by the member’s benefit document and applicable state/federal mandates; absence of benefit coverage or restrictions may lead to denial regardless of medical necessity.

Confirm member eligibility and plan benefits for HBOT and topical oxygen devices
Obtain and document prior authorization when required by the plan before initiating therapy
Notify members if services are non-covered or considered experimental/unproven under their plan

Denial Risk

Denial risk for unproven indications

Requests for indications not supported by sufficient evidence (including most uses of mild hyperbaric therapy and topical oxygen therapy for many wound types) carry a high denial risk. Provide high-quality, indication-specific evidence if requesting coverage for nonstandard indications.

Expect denials for mHBOT (mild hyperbaric) and unproven topical oxygen uses absent compelling high-quality evidence
Submit peer-reviewed literature and rationale for off-label or investigational requests
Document why standard therapies are inadequate and why HBOT is reasonably expected to help

Denial Risk

Failure to integrate HBOT with appropriate surgery and antibiotics and to provide adequate treatment course

Authorization requests that fail to demonstrate integration of HBOT with appropriate surgical interventions and culture-directed antibiotics for infectious indications (e.g., chronic/refractory osteomyelitis, intracranial abscess, necrotizing infections) are at risk of denial. HBOT is an adjunct and should not replace standard, timely, and definitive care.

Provide operative reports, culture results, antibiotic regimens and duration, and timing of HBOT relative to surgery
Clarify that HBOT will be given as adjunctive therapy and will not delay required operative or critical care interventions

Denial Risk

Insufficient Evidence Risk

Some indications have limited or inconsistent evidence. When requesting HBOT for conditions with mixed evidence (e.g., carbon monoxide poisoning, compromised grafts/flaps, select burn or graft scenarios), include controlled trial data or society guideline support to justify treatment and explain limitations.

Cite randomized trials, meta-analyses, or authoritative society guidance when available
Discuss anticipated short-term vs long-term benefits and any limitations of the evidence base

Denial Risk

Lack of persistent long-term benefit in some trials (DFU)

For DFUs, short-term wound healing benefit has been shown in some trials but consistent long-term persistence of benefit (e.g., at 1 year) is not established. Authorization requests should set realistic expectations and include follow-up plans and objective healing metrics.

Include baseline wound measurements and planned intervals for reassessment (e.g., 6 weeks, 12 weeks)
Document criteria for continuing vs discontinuing HBOT based on objective wound response

Denial Risk

mHBOT/Low-pressure chamber risks

Mild hyperbaric oxygen therapy (mHBOT) delivered in low-pressure fabric or semirigid chambers (<1.4 ATA) is not considered therapeutic HBOT. These devices have limited evidence of efficacy, are cleared by FDA primarily for altitude sickness, and do not meet UHMS criteria for approved HBOT indications.

Do not authorize mHBOT as replacement for therapeutic HBOT indications
If mHBOT is proposed, provide evidence and clear clinical justification; expect denial for standard HBOT indications

Prior Authorization

Benefit plan conformity required

All authorization decisions must conform to the member-specific benefit plan. Even when medical necessity criteria are met by clinical documentation, services may be non-covered or limited by plan exclusions, benefit caps, or state/federal mandates.

Confirm benefit coverage, any visit/annual limits, and whether TOT or HBOT devices are covered under the member’s plan
If a service is medically necessary but not covered, provide notification to the member and document alternatives

Documentation Required

Documentation expectations

Documentation expectations: provide clear, contemporaneous clinical records that state diagnosis, objective wound or disease stage/grade, prior and concurrent therapies (dates and outcomes), and the specific HBOT treatment plan (pressure, session length, frequency, total planned sessions).

Include objective measures (wound size, imaging, vascular studies, microbiology) and response to prior therapies
Provide treatment goals and objective criteria for assessing response during/after HBOT

Prior Authorization

Required Treatment Course and History

Required treatment course and history must be provided to support authorization: detailed prior conservative care, duration and adequacy of antibiotics and surgeries (for infectious indications), and prior wound therapies (debridement, offloading, vascular interventions) for DFUs. Specify the intended HBOT regimen and planned total number of sessions.

List prior treatments with dates and objective outcomes (e.g., % wound area reduction over specified weeks)
State proposed HBOT protocol: pressure (ATA), minutes per session, sessions per week, and planned total sessions

Documentation Required

Intracranial abscess documentation

When intracranial abscess is the indication, provide neurosurgical and infectious disease documentation, imaging reports (CT/MRI), abscess size/location, number of lesions, source control measures performed, antibiotic regimens and durations, and rationale for adjunctive HBOT (e.g., deep-seated/multiple lesions, poor response to standard care).

Attach operative reports and serial imaging demonstrating response or progression
Provide infectious disease consultation notes and planned antibiotic duration if HBOT is approved

Documentation Required

Documentation and evidence sources

Support clinical rationale with evidence sources and citation of guidelines, systematic reviews, or controlled trials when available. For off-label or less-established uses, include peer-reviewed literature and a succinct evidence summary to aid utilization review.

Provide copies or citations of the most relevant literature and society guidance supporting the requested indication
Summarize key outcomes and how they relate to the member’s clinical scenario

Documentation Required

For avascular necrosis and chronic osteomyelitis: Provider actions

For avascular necrosis (AVN) and chronic osteomyelitis, include staging/grade (e.g., Ficat stage for AVN), imaging reports (MRI/radiographs), prior orthopedic interventions (core decompression, fixation), and documentation of symptom duration and functional impact. If HBOT is requested as adjunct or alternative to surgery, provide comparative rationale.

Provide Ficat stage or equivalent, symptom timeline, and prior orthopedic/surgical treatment details
If HBOT accompanies surgery, document timing relative to surgery and intended role (salvage, adjunctive therapy)

Prior Authorization

HBOT is positioned as an adjunctive or escalation therapy after failure of standard wound care

HBOT should be positioned and authorized only as adjunctive or escalation therapy after adequate trials of standard wound care, antibiotics, and when appropriate, surgical interventions. Authorization requests must describe why HBOT is necessary beyond standard care and how it will be integrated into the overall plan.

Document prior standard care attempts and objective failure criteria (e.g., <50% wound area reduction after 4 weeks)
State how HBOT will be coordinated with ongoing wound care, vascular procedures, or antibiotics

Denial Risk

Adjunctive use must not delay standard care

Adjunctive HBOT must not delay standard of care interventions (surgery, vascular revascularization, critical care). If HBOT is being considered, provide scheduling plans that ensure timely definitive care is not postponed.

Clarify timelines showing that HBOT will not postpone necessary surgery or urgent interventions
If transfer for HBOT is proposed, document that critical care will not be delayed by transfer

Prior Authorization

Adjunctive TOT after standard care

Topical oxygen therapy (TOT) may be considered only after standard wound therapies have failed and when resources exist to support its use. Authorization for TOT should include method of application, frequency/duration, and evidence supporting the chosen device or protocol; expect conditional review due to lower certainty of evidence.

Provide device model (CPT/HCPCS codes where applicable) and treatment parameters
Include prior wound care history and objective measures documented before TOT initiation

Background and Definitions

Background: Hyperbaric Oxygen Therapy (HBOT) involves intermittent inhalation of near‑100% oxygen inside a pressurized chamber at pressures that must equal or exceed 1.4 ATA while the patient breathes oxygen to meet the clinical definition of therapeutic HBOT. HBOT can be used as a primary therapy in some indications or as an adjunct to surgical and pharmacologic interventions in others. Mild hyperbaric chambers operate at lower pressures and are FDA‑cleared only for acute mountain sickness; they do not meet the therapeutic HBOT definition and are not considered equivalent for clinical indications.

inv-64: Hyperbaric Oxygen Therapy definition

DefinitionIntermittent breathing of near 100% oxygen inside a hyperbaric chamber pressurized to >=1.4 ATA; may be primary therapy or adjunct to surgery/pharmacologic interventions (UHMS guidance)

Chamber typesAdministered in Class A (multiplace) or Class B (monoplace) chamber systems; oxygen delivered via ambient chamber atmosphere or masks/hoods/tubes depending on system configuration

Clinical contextUsed for multiple indications when delivered at therapeutic pressures and durations consistent with guideline recommendations

inv-65: Mild Hyperbaric Oxygen Therapy definition

DefinitionLow-pressure fabric hyperbaric chambers that deliver pressures <1.4 ATA and have been FDA-cleared for acute mountain sickness only; exposures <1.4 ATA while patient breathes air do not meet therapeutic HBOT definition (UHMS)

Regulatory/clearance noteFDA 510(k) clearance exists for acute mountain sickness for some devices, but mHBOT does not achieve UHMS therapeutic pressures

Coverage stancePolicy describes mild HBOT as unproven and not medically necessary for indications listed for therapeutic HBOT

inv-66: Topical Oxygen Therapy definition

DefinitionDirect application of oxygen to a wound site via sealed enclosure (slightly above atmospheric pressure) or continuous delivery through a cannula beneath a dressing to improve tissue oxygenation in hypoxic tissue

Typical scheduleCommonly described as 90-minute sessions administered three to five times per week or continuous therapy depending on device and protocol

Evidence/coverage noteQuality evidence is limited; IWGDF provides conditional recommendations and UHMS advises topical oxygen not be routine clinical treatment pending more evidence

inv-67: Ficat staging

PurposeRadiographic staging system for femoral head osteonecrosis used to select early-stage patients likely to benefit from HBOT or core decompression

Clinical useStudies and meta-analyses referenced Ficat stages I–II (precollapse) as the stage where HBOT shows clinical improvement in pain, function, and imaging

Evidence noteAuthors call for larger RCTs despite cohort and meta-analytic signals of benefit in early-stage disease

inv-68: refractory osteomyelitis definition

DefinitionBone infection not responding adequately to culture-directed antibiotics and surgical debridement (refractory osteomyelitis)

Treatment contextHBOT is recommended as an adjunct to antibiotics and surgical debridement; ECHM and UHMS describe improved remission rates when combined

Suggested courseECHM suggests extended courses (approximately 60 sessions over 11–12 weeks) with repeated evaluation of effect

inv-69: compromised grafts/flaps definition

DefinitionTissue graft or flap with decreased perfusion or hypoxia that is potentially salvageable if treated promptly with adjuncts such as HBOT (compromised grafts/flaps)

Timing importanceUHMS and ECHM emphasize starting HBOT as soon as signs of compromise appear to maximize salvage potential

ECHM regimen summaryECHM suggests HBOT at 203–253 kPa for >=60 minutes, repeated multiple times first day then daily until viability is determined

inv-70: Wagner grade (2-4 referenced) definition

Wagner grading overviewA commonly used wound classification for diabetic foot ulcers; policy references Wagner grades 2–4 as the levels where adjunctive HBOT demonstrates benefit

Evidence specificsSystematic reviews/meta-analyses report improved healing and reduced amputation rates for Wagner grades 2–4, with UHMS recommending HBOT for grade >=3

Clinical thresholdStudies typically included ulcers persisting >=30 days or failing standard care prior to HBOT enrollment

inv-71: ISSNHL ≥ 40 dB threshold

ISSNHL severity threshold>= 40 dB (moderate to profound hearing loss) is the UHMS threshold for recommending HBOT in ISSNHL patients presenting within 14 days)

Timing requirementRecommended treatment window is within 14 days of symptom onset for best evidence of benefit; AAO-HNS recommends combined therapy within 2 weeks

Salvage noteAAO-HNS supports salvage HBOT combined with steroids within 1 month in selected patients

inv-72: mild hyperbaric oxygen therapy (mHBOT) definition (duplicate)

Definition (duplicate)Low-pressure hyperbaric treatments (pressures <1.4 ATA while patient breathes air) that do not meet UHMS therapeutic HBOT definitions and lack robust evidence of clinical benefit

Regulatory clearanceSome mHBOT devices have FDA 510(k) clearance for acute mountain sickness but are not equivalent to therapeutic HBOT

Coverage stancePolicy lists mild HBOT as unproven and not medically necessary for therapeutic indications

inv-73: mHBOT (fabric chambers) definition (duplicate)

Fabric chamber descriptionMild hyperbaric oxygen therapy using fabric chambers provides exposures <1.4 ATA while patient breathes air and does not meet UHMS definition of therapeutic HBOT

Safety/regulatory concernsAMA has expressed concerns about mHBOT facilities and supports oversight to ensure physician supervision and safety compliance

FDA clearance noteSome semirigid/low-pressure chambers classified under FDA processes are intended for altitude sickness and operate at lower pressures (see product code CBF details)

inv-74: FDA device classifications

Device classHyperbaric chambers and topical oxygen devices are FDA Class II devices (informational only)

Hyperbaric chamber product codeCBF (used for hyperbaric chamber 510(k) references and MAUDE adverse event searches)

Topical oxygen product codeKPJ (used for topical oxygen therapy device 510(k) references)

inv-75: UHMS guidance referenced

UHMS roleUHMS position statements and indications manuals (2019, 2023) are cited as primary guidance for accepted HBOT indications and pressure/duration parameters

UHMS specificsUHMS recommends 30–60 treatments at 2.0–2.5 ATA for 90–120 minutes for delayed radiation injury and includes ISSNHL and other indications in its indications manual

Position on mHBOT and topical oxygenUHMS states low-pressure fabric chambers (<1.4 ATA) do not meet therapeutic HBOT definition and advises topical oxygen not be routine clinical treatment pending more evidence

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

OpenPayer

Hyperbaric Oxygen Therapy and Topical Oxygen Therapy

Coverage Criteria for HBOT, mHBOT, and Topical Oxygen

Procedure, Supply, and Device Codes

Prior Authorization, Documentation, and Operational Guidance

Background and Definitions

Policy Revision History