HBOT Referral Guidelines for Surgeons

When to Request Hyperbaric Consultation for Compromised Reconstructions, Acute Trauma, Infection, Radiation Injury, and Complex Wounds

Hyperbaric oxygen therapy, commonly abbreviated as HBOT, is most useful to surgeons when it addresses a defined threat to tissue viability, infection control, or postoperative healing. It is not a routine method for accelerating recovery after an uncomplicated operation.

A referral should identify the specific surgical problem that HBOT may help address. Examples include a compromised flap that remains viable after correction of a mechanical cause, acute traumatic ischemia following revascularization, chronic refractory osteomyelitis after appropriate source control, or surgery within tissue damaged by radiation.

The Undersea and Hyperbaric Medical Society, or UHMS, recognizes several surgical and perioperative applications of HBOT, including compromised grafts and flaps, crush injury and acute traumatic ischemia, necrotizing soft tissue infection, refractory osteomyelitis, delayed radiation injury, and selected advanced diabetic wounds. Medicare coverage overlaps with several of these indications but applies its own medical-necessity and documentation requirements. (UHMS)

Referral Should Begin With the Surgical Diagnosis

The presence of a difficult wound is not, by itself, an indication for HBOT. The surgeon and hyperbaric physician must first determine why the tissue is failing.

Potential barriers include:

• Arterial obstruction

• Venous congestion

• Hematoma or seroma

• Excessive closure tension

• Flap pedicle compression or thrombosis

• Infection

• Retained necrotic tissue

• Radiation-associated vascular damage

• Repetitive pressure or shear

• Poorly controlled edema

• Inadequate offloading

• Malnutrition or metabolic dysfunction

HBOT can increase dissolved plasma oxygen, extend oxygen diffusion from functioning capillaries, reduce selected forms of edema, and support oxygen-dependent immune and reparative processes. It cannot correct a twisted pedicle, evacuate a hematoma, drain an abscess, reopen an occluded artery, stabilize a fracture, or remove necrotic tissue.

The central referral question is therefore:

Does the patient have hypoxic but viable tissue that may benefit from increased oxygen delivery after correctable surgical problems have been addressed?

Use Three Levels of Referral Urgency

Surgeons can organize HBOT referrals according to the rate at which tissue or organ viability is being lost.

Immediate emergency consultation is appropriate when treatment delay may result in major neurologic injury, limb loss, organ damage, or death. Examples include arterial gas embolism, severe carbon monoxide poisoning, decompression illness, and selected acute traumatic ischemias.

Urgent same-day consultation is appropriate for a compromised graft or flap, progressive traumatic tissue ischemia, necrotizing infection after emergency surgical evaluation, or threatened replanted tissue.

Planned consultation is generally appropriate for delayed radiation injury, chronic refractory osteomyelitis, selected advanced diabetic foot wounds, and preparation for complex surgery within a previously irradiated field.

Early consultation does not obligate the patient to undergo HBOT. It allows the hyperbaric team to determine whether an indication exists, whether additional source control is required, and whether the tissue remains salvageable.

Compromised Flaps Require Immediate Surgical Assessment

A threatened flap is one of the most time-sensitive surgical reasons to contact a hyperbaric center.

Warning findings may include:

• Increasing pallor

• Cyanosis or dark venous congestion

• Cool tissue

• Delayed capillary refill

• Progressive edema

• Loss or deterioration of a Doppler signal

• Epidermolysis

• Poor bleeding after pinprick

• Expanding tissue necrosis

The reconstructive surgeon must first evaluate for a surgically correctable cause. Arterial thrombosis, venous thrombosis, pedicle kinking, compression, hematoma, excessive tension, or technical anastomotic failure may require immediate return to the operating room.

HBOT should not be used as a substitute for flap exploration. It may be considered after mechanical and vascular causes have been corrected when tissue remains hypoxic but potentially viable.

UHMS states that HBOT is neither necessary nor recommended for normal, uncompromised grafts and flaps. Its role is as an adjunct for compromised tissue, and early initiation after compromise is recognized may improve the opportunity for salvage. (UHMS)

A strong referral communicates:

• Type and location of the flap

• Date and time of reconstruction

• Arterial and venous anatomy

• Onset and progression of compromise

• Doppler and clinical findings

• Operative revision already performed

• Presence of hematoma, infection, or venous congestion

• Current photographs

• Specific tissue the surgeon is attempting to preserve

The objective should be explicit, such as preserving complete flap coverage, reducing the area of debridement, avoiding implant exposure, or preventing the need for another free-tissue transfer.

Skin Graft Referral Should Be Selective

A skin graft depends on direct contact with a vascular recipient bed, early diffusion of oxygen and nutrients, and subsequent capillary connection. Hematoma, seroma, movement, infection, ischemia, and an inadequate wound bed can interfere with graft uptake.

Before referral, the surgeon should address:

• Fluid beneath the graft

• Loss of graft-to-bed contact

• Shear or displacement

• Constricting dressings

• Infection

• Inadequate debridement

• Recipient-bed perfusion

• Exposed structures that cannot support grafting

HBOT may be considered when a graft remains threatened by tissue hypoxia after these factors have been corrected. Medicare covers the preparation and preservation of compromised skin grafts, while specifically excluding HBOT as the primary management of ordinary wounds. (Centers for Medicare & Medicaid Services)

Routine prophylactic HBOT is not indicated for every split-thickness or full-thickness skin graft. Referral should describe an actual or highly credible threat to graft viability rather than the presence of a graft alone.

Replanted and Revascularized Tissue May Remain at Risk

Successful restoration of major arterial inflow does not immediately normalize the microcirculation. Replanted or revascularized tissue may remain threatened by edema, venous congestion, microvascular thrombosis, endothelial injury, and ischemia-reperfusion effects.

The vascular or reconstructive team must first confirm that the repair is technically intact. Loss of inflow, venous obstruction, compartment pressure, or compressive hematoma requires direct intervention.

HBOT may be considered when adequate macroscopic circulation has been restored but tissue remains at risk because of microvascular compromise. Medicare includes crush injury and the suturing of severed limbs among covered hyperbaric conditions when function, limb, or life is threatened. (Centers for Medicare & Medicaid Services)

Serial assessment should include:

• Arterial and venous Doppler findings

• Capillary refill

• Tissue temperature

• Motor and sensory function

• Compartment findings

• Edema

• Demarcation of necrosis

• Need for further operative revision

The treatment objective should be tissue preservation, not simply temporary improvement in color during oxygen exposure.

Acute Traumatic Ischemia Should Be Referred Early

Severe crush injury, open fracture, vascular disruption, and reperfusion can create a cycle of edema, microvascular compression, hypoxia, inflammation, and additional tissue loss.

HBOT may support viable tissue by increasing oxygen diffusion and reducing edema while definitive trauma care continues. It cannot replace:

• Hemorrhage control

• Vascular repair

• Fracture stabilization

• Fasciotomy

• Debridement

• Antibiotic treatment

• Management of rhabdomyolysis and systemic crush syndrome

The multicenter HOLLT randomized trial evaluated adjunctive HBOT after initial surgery for severe open lower-limb fractures. The combined primary outcome of necrosis or infection was numerically lower but not statistically significant. Tissue necrosis considered separately was lower in the HBOT group, and several later functional outcomes favored treatment. These findings support selective use in severe lower-limb trauma without justifying routine HBOT for every open fracture. (PubMed Central (PMC))

Referral is most appropriate when the surgeon believes there is a reversible zone of threatened tissue and preservation could change the level of debridement, reconstructive plan, limb function, or amputation risk.

The referral should include:

• Mechanism and time of injury
• Vascular findings
• Fracture classification
• Compartment findings
• Operative reports
• Debridement and fixation completed
• Revascularization status
• Current photographs
• Planned return to the operating room
• Critical-care and monitoring requirements

Compartment Syndrome Still Requires Fasciotomy

Acute compartment syndrome is a surgical emergency. HBOT must not delay decompression when clinical findings or pressure measurements support fasciotomy.

Hyperbaric consultation may become relevant after fasciotomy when:

• Muscle remains severely edematous and ischemic
• Viability is uncertain
• A high-energy crush mechanism threatens marginal tissue
• Reperfusion injury is progressing
• Additional tissue loss would materially affect limb function

An open but inadequately decompressed compartment still requires surgical reassessment. A chamber treatment should never be used as evidence that another operation is unnecessary.

Necrotizing Infection Requires Source Control First

Necrotizing fasciitis, Fournier gangrene, and clostridial myonecrosis require immediate operative evaluation, broad-spectrum antimicrobial therapy, resuscitation, and critical care.

IDSA recommends prompt surgical consultation for aggressive soft tissue infections associated with systemic toxicity or suspected necrotizing fasciitis or gas gangrene. It also recommends broad empiric antimicrobial therapy because these infections may be polymicrobial or monomicrobial. (IDSA)

HBOT may be considered after emergency source control has begun. Proposed benefits include support for leukocyte microbial killing, increased oxygenation of threatened tissue, edema reduction, and inhibition of selected anaerobic organisms or toxins.

The referral should not delay:

• Initial debridement
• Repeat debridement
• Antibiotic administration
• Hemodynamic resuscitation
• Airway support
• Drainage of an abscess
• Amputation when required for survival

A practical sequence is:

1. Recognize the surgical emergency.
2. Begin resuscitation and broad antimicrobial therapy.
3. Perform urgent exploration and debridement.
4. Stabilize the patient.
5. Contact the hyperbaric team if treatment can be integrated without delaying another operation.
6. Continue repeated surgical reassessment.

Transfer to another facility solely for HBOT may be harmful when the patient is unstable or immediate surgical care would be interrupted.

Chronic Osteomyelitis Should Be Refractory Before Referral

HBOT is not routine first-line treatment for acute osteomyelitis or every postoperative bone infection.

Referral is most appropriate for chronic refractory osteomyelitis that has persisted or recurred despite appropriate medical and surgical treatment. Medicare defines the covered indication as chronic refractory osteomyelitis unresponsive to conventional medical and surgical management. (Centers for Medicare & Medicaid Services)

Before referral, the surgical plan should address:

• Necrotic or sequestrated bone
• Abscesses
• Infected hardware
• Mechanical instability
• Sinus tracts
• Vascular insufficiency
• Culture-directed antimicrobial therapy
• Soft-tissue coverage

Useful referral records include:

• Operative reports
• Bone or deep-tissue cultures
• Pathology
• Imaging
• Antibiotic history
• Hardware status
• Vascular testing
• Previous reconstruction
• Evidence of persistence or recurrence

HBOT may improve oxygen-dependent immune activity and support bone and soft-tissue repair. It cannot sterilize an undebrided sequestrum or compensate for unstable fixation.

The hyperbaric physician, infectious disease specialist, and surgeon should agree on the treatment objective. This may include infection suppression before reconstruction, support of a limb-salvage procedure, or treatment after adequate debridement of recurrent disease.

Diabetic Foot Surgery Requires Comprehensive Standard Care

A diabetic foot wound should not be referred solely because it is chronic or postoperative.

The IWGDF conditionally recommends considering systemic HBOT for selected neuro-ischemic or ischemic diabetes-related foot ulcers when standard care has failed and the resources required for treatment are available. The certainty of evidence is considered low, making patient selection especially important. (IWGDF Guidelines)

Medicare generally requires:

• Type 1 or type 2 diabetes
• A lower-extremity wound related to diabetes
• Wagner grade III or higher
• Failure of at least 30 days of standard wound therapy
• Continued comprehensive wound care during HBOT
• Periodic documentation of measurable improvement

Covered standard care includes vascular assessment, revascularization when appropriate, debridement, offloading, glucose management, nutritional optimization, moist wound care, and treatment of infection. (Centers for Medicare & Medicaid Services)

Surgeons should obtain urgent consultation for severe diabetic foot infection, extensive gangrene, necrotizing infection, deep abscess, compartment syndrome, or severe ischemia. The 2023 IWGDF and IDSA infection guidance recommends early surgery with antibiotics for selected moderate and severe infections and urgent surgical consultation for these high-risk findings. (IDSA)

A hyperbaric referral should include:

• Wound location and duration
• Wagner classification
• Serial measurements
• Photographs
• Offloading method
• Vascular studies and interventions
• Debridement history
• Infection and osteomyelitis evaluation
• Culture results
• Glucose management
• Response during standard treatment

HBOT should not be used to postpone revascularization, drainage, debridement, or amputation when those interventions are required.

Radiation-Damaged Tissue Requires Diagnosis-Specific Planning

Previous radiation can produce progressive small-vessel injury, fibrosis, reduced tissue oxygenation, impaired cellular repair, and poor surgical healing. Symptoms may appear months or years after cancer treatment.

Surgeons may consider referral for:

• Soft tissue radionecrosis
• Osteoradionecrosis
• Chronic ulceration within a radiation field
• Nonhealing postoperative wounds in irradiated tissue
• Selected reconstructive procedures involving significantly damaged tissue
• Radiation cystitis or proctitis identified during surgical evaluation

Medicare covers soft tissue radionecrosis and osteoradionecrosis when HBOT is used as an adjunct to conventional treatment. UHMS also recognizes delayed radiation injury as an established hyperbaric indication. (Centers for Medicare & Medicaid Services)

The referral should include:

• Cancer diagnosis
• Radiation site
• Total dose and treatment dates
• Radiation plan or dose map when available
• Previous operations
• Current imaging
• Pathology
• Evidence excluding recurrent malignancy
• Extent of exposed or necrotic tissue
• Planned debridement or reconstruction

A new wound, mass, bleeding episode, or bone lesion within a previous cancer field should not automatically be attributed to radiation. Recurrence, infection, fistula, vascular disease, and a second malignancy may require investigation.

Routine Dental Prophylaxis After Radiation Is Not Automatically Indicated

Historical protocols frequently used HBOT around dental extraction or mandibular surgery after head and neck radiation. Current evidence supports a more selective approach.

The 2024 ISOO-MASCC-ASCO guideline concluded that evidence supporting routine HBOT for prevention or management of osteoradionecrosis of the jaw remains limited. The guideline emphasizes contemporary dental prevention, careful surgical technique, multidisciplinary assessment, and individualized management rather than automatic hyperbaric treatment for every post-radiation extraction. (ASCO Publications)

Referral may still be reasonable when:

• Established osteoradionecrosis is present
• A substantial volume of poorly vascularized irradiated bone is involved
• Previous surgery has failed
• Complex debridement and reconstruction are planned
• Soft tissue radionecrosis accompanies the bone injury
• The hyperbaric physician and head and neck team identify a specific treatment objective

The surgeon should provide radiation-dose information, dental imaging, the proposed operation, bone exposure history, infection findings, and evidence excluding recurrent disease.

Acute Thermal Burns Require Selective Referral

UHMS recognizes acute thermal burn injury as a hyperbaric indication, but HBOT is not routine treatment for every burn. Its proposed role is preservation of hypoxic but viable tissue within the zone surrounding irreversible injury.

Burn-center priorities remain:

• Airway management
• Fluid resuscitation
• Escharotomy or fasciotomy when indicated
• Early excision
• Grafting
• Infection management
• Nutritional support
• Rehabilitation

Referral may be considered for selected severe burns, threatened tissue, compromised grafts or flaps, or when the fire exposure has also caused carbon monoxide poisoning.

Coverage requires separate verification because Medicare nationally excludes thermal skin burns as a covered HBOT indication, even though a distinct complication such as carbon monoxide poisoning or a compromised graft may qualify independently. (Centers for Medicare & Medicaid Services)

Severe Perioperative Anemia Is an Exceptional Indication

In rare circumstances, a surgical patient may develop life-threatening anemia when transfusion is unavailable, incompatible, or declined.

HBOT can temporarily increase oxygen dissolved in plasma while the team:

• Stops hemorrhage
• Minimizes further blood loss
• Supports erythropoiesis
• Reduces unnecessary phlebotomy
• Optimizes cardiac output and ventilation
• Determines which blood products or alternatives are acceptable

HBOT does not restore red blood cell mass and should not delay operative hemostasis. This application requires a hospital-based hyperbaric facility capable of managing a critically ill patient under pressure.

Severe anemia is recognized by UHMS, but Medicare does not nationally cover exceptional blood-loss anemia under its current HBOT policy. (UHMS)

Do Not Refer Normal Postoperative Healing

HBOT is generally not indicated for:

• An uncomplicated surgical incision
• A healthy flap with normal perfusion
• A graft progressing normally
• Routine cosmetic surgery recovery
• Prevention of ordinary scarring
• Mild postoperative edema
• A superficial wound without optimized standard care
• Cellulitis without a recognized hyperbaric indication
• An undrained abscess
• An untreated arterial obstruction
• Routine rehabilitation after surgery

The fact that oxygen participates in healing does not mean that additional oxygen under pressure improves every postoperative outcome.

A referral should be based on a defined pathologic process, not a general desire to heal faster.

What to Do Before Contacting the Hyperbaric Center

For a chronic or nonemergency referral, surgeons should complete the diagnostic workup and initiate appropriate standard treatment.

Depending on the condition, this may include:

• Vascular assessment
• Imaging
• Deep cultures
• Pathology
• Debridement
• Antibiotic therapy
• Mechanical offloading
• Glucose optimization
• Nutritional assessment
• Smoking and nicotine counseling
• Evaluation for recurrent malignancy
• Revision of a compromised reconstruction

Emergency referrals are different. Consultation should occur in parallel with stabilization and surgery rather than after every diagnostic test has been completed.

Information to Include in the Referral

A complete referral allows the hyperbaric team to determine urgency, eligibility, and treatment safety without unnecessary delay.

Include:

• Specific diagnosis
• Clinical objective for HBOT
• Date and mechanism of injury or operation
• Symptom and wound timeline
• Operative reports
• Current photographs
• Imaging
• Pathology and cultures
• Vascular studies
• Radiation records
• Antibiotic history
• Standard care already completed
• Planned future operations
• Current medications
• Pulmonary and seizure history
• Implanted devices
• Need for ventilation, infusions, or invasive monitoring
• Insurance and authorization information when relevant

For a flap, graft, replanted part, or traumatic ischemia, direct surgeon-to-hyperbaric physician communication is preferable to a routine electronic referral.

Describe the Intended Endpoint

HBOT should begin with a measurable objective.

Possible endpoints include:

• Preservation of a graft or flap
• Reduction in the area requiring debridement
• Successful coverage of exposed bone or hardware
• Control of chronic radiation-related tissue breakdown
• Progress toward closure of a qualifying diabetic wound
• Improvement after treatment of refractory osteomyelitis
• Preservation of limb function
• Stabilization of threatened traumatic tissue

The treatment course should be reassessed when:

• Tissue necrosis continues to progress
• A new surgical problem appears
• No objective improvement is occurring
• Another operation becomes necessary
• The clinical objective has been achieved
• The patient can no longer be treated safely

A predetermined number of chamber sessions should not replace surgical and hyperbaric reassessment.

Prepare the Patient for Hyperbaric Safety Screening

The hyperbaric physician will make the final safety determination, but the surgeon should identify important concerns before transfer.

These may include:

• Known or suspected pneumothorax
• Significant chest trauma
• Pulmonary air trapping
• Mechanical ventilation
• Continuous infusions
• Implanted electronic devices
• External fixation
• Drains and negative-pressure systems
• Recent ear or sinus surgery
• Seizure history
• Fever
• Glucose instability
• Pregnancy
• Claustrophobia

Dressings, topical products, warming systems, batteries, electronics, and implanted devices must be reviewed for compatibility with the specific chamber.

The FDA advises hyperbaric facilities to follow the manufacturer’s instructions, monitor patients continuously, maintain trained staff, use appropriate grounding, perform required maintenance, and enforce strict fire-prevention controls. (U.S. Food and Drug Administration)

Refer to a Center With the Required Capability

Not every hyperbaric center can treat every surgical patient.

A stable outpatient with delayed radiation injury may be appropriate for a monoplace wound-center program. An intubated trauma patient, unstable necrotizing infection, or patient receiving vasoactive infusions requires a hospital program with appropriate chamber access, critical-care equipment, and trained personnel.

Before transfer, confirm:

• The center treats the specific indication.
• A qualified hyperbaric physician has accepted the patient.
• The facility can manage the patient’s acuity.
• Chamber-compatible equipment is available.
• Required surgical and critical-care support will remain accessible.
• Transfer will not delay a more urgent intervention.

The most sophisticated chamber cannot compensate for a facility that lacks appropriate staffing, emergency capability, or multidisciplinary support.

Coordinate Chamber Treatments With Surgical Care

Hyperbaric treatment should be integrated around the operative plan.

For time-sensitive conditions, the surgeon and hyperbaric physician should agree on:

• Timing of the next operation
• Whether HBOT should occur before or after surgery
• Frequency of wound inspection
• Dressing and device compatibility
• Criteria for return to the operating room
• Reassessment of tissue viability
• Treatment discontinuation criteria

A scheduled HBOT session should be cancelled or postponed when the patient needs an urgent operation.

The hyperbaric team should also know when a wound must remain covered, when a flap cannot be compressed, when an extremity needs a particular position, and whether drains or external fixation require special handling.

Clinical Recognition and Coverage Are Separate Decisions

Surgeons should distinguish among:

• Recognition by a professional hyperbaric organization
• Medical appropriateness for an individual patient
• Medicare national coverage
• Commercial payer authorization
• Facility capability

A patient may have a clinically recognized indication that is not covered by a particular payer. Another patient may have a covered diagnosis but fail to meet severity, standard-care, or continued-treatment requirements.

The hyperbaric center should verify coverage and authorization. The referring surgeon supports that process by documenting the diagnosis, severity, previous treatment, operative findings, and clinical objective accurately.

The Best Referral Occurs While Tissue Is Still Salvageable

The potential benefit of HBOT decreases when tissue has become irreversibly necrotic or when a correctable surgical problem remains untreated.

Surgeons should contact the hyperbaric team early when:

• A flap begins showing signs of compromise
• Replanted tissue remains ischemic after repair
• A crush injury has a threatened zone of viable tissue
• Radiation damage is complicating an operative plan
• Osteomyelitis is becoming refractory
• A qualifying diabetic wound fails despite comprehensive care

Early consultation allows the surgeon and hyperbaric physician to determine whether HBOT can change the reconstructive, functional, or limb-salvage outcome.

The chamber is most valuable when it supports decisive surgical care. It should never replace source control, vascular correction, debridement, fixation, reconstruction, or careful postoperative surveillance.