HBOT for Compromised Skin Grafts

Using Hyperbaric Oxygen Therapy to Support Graft Uptake, Preserve Viable Tissue, and Reduce the Need for Repeat Reconstruction

Skin grafting allows surgeons to cover wounds that cannot be closed primarily. Grafts are used after trauma, burns, tumor removal, infection control, debridement, and reconstructive procedures. Successful grafting can protect exposed tissue, reduce fluid loss, improve function, and shorten the time required for wound closure.

Unlike a flap, a skin graft is completely separated from its original blood supply. It must survive temporarily through diffusion from the recipient bed and then establish new vascular connections. Any process that interferes with contact, oxygen delivery, or revascularization can cause partial or complete graft loss.

Hyperbaric oxygen therapy, commonly abbreviated as HBOT, may be considered when a skin graft becomes compromised by hypoxia or impaired perfusion. It is not recommended routinely for a healthy graft that is progressing normally. The Undersea and Hyperbaric Medical Society identifies compromised grafts and flaps as an accepted indication, emphasizing that HBOT is a salvage adjunct for threatened tissue rather than routine support for uncomplicated reconstruction. (UHMS)

How a Skin Graft Establishes a Blood Supply

A skin graft does not immediately receive blood through its own circulation after placement. Early survival depends on a staged relationship with the recipient wound bed.

During the first phase, known as plasmatic imbibition, the graft absorbs oxygen, nutrients, and fluid from the underlying tissue. This diffusion-based support helps preserve graft cells while more permanent vascular connections are developing.

During inosculation, small vessels within the graft align with vessels in the recipient bed. Blood flow begins to enter the graft as these vascular channels connect.

Revascularization then progresses through capillary ingrowth and remodeling. The graft gradually develops a more dependable circulation capable of supporting long-term survival.

These stages require:

• Close contact between the graft and wound bed
• An adequately vascularized recipient surface
• Control of bleeding and fluid accumulation
• Protection from movement and shear
• Management of infection
• Sufficient tissue oxygenation

A disruption during the early postoperative period may prevent vascular connection and lead to graft separation, ischemia, or necrosis.

Split-Thickness and Full-Thickness Skin Grafts

A split-thickness skin graft contains the epidermis and a portion of the dermis. Because it is relatively thin, it can receive nutrients by diffusion more readily and may survive on a less vascular recipient bed than a thicker graft.

Split-thickness grafts are commonly used to cover:

• Large traumatic wounds
• Burn wounds
• Chronic ulcers
• Donor sites
• Wounds following debridement
• Areas prepared with dermal substitutes

A full-thickness skin graft contains the epidermis and the complete dermis. It generally provides better durability, contour, texture, and resistance to contraction, but it has greater metabolic requirements and depends on a well-vascularized recipient bed.

HBOT may be relevant to either graft type when tissue oxygenation is inadequate. The graft’s thickness, location, recipient bed, wound cause, and degree of compromise all influence the likelihood of salvage.

Why Skin Grafts Become Compromised

A compromised graft is one that is at meaningful risk of partial or complete failure. The underlying cause must be identified quickly because HBOT cannot correct every mechanism of graft loss.

Common causes include:

• Hematoma beneath the graft
• Seroma or fluid accumulation
• Infection
• Shear or excessive movement
• Poor graft fixation
• Inadequate recipient-bed preparation
• Arterial insufficiency
• Venous congestion
• Severe edema
• Previous radiation exposure
• Diabetes-related microvascular dysfunction
• Tobacco or nicotine exposure
• Excessive pressure from dressings
• Repeated trauma
• Malnutrition
• Immunosuppression
• Extensive crush or burn injury

Exposed cortical bone without periosteum, tendon without paratenon, cartilage without perichondrium, and poorly vascularized scar tissue may not provide an adequate recipient bed unless additional preparation or reconstruction is performed.

HBOT should not be used to avoid correcting a mechanical, vascular, infectious, or surgical cause of graft failure.

Recognizing Early Graft Compromise

Early recognition is important because viable but hypoxic tissue may still be salvageable. Once graft tissue becomes irreversibly necrotic, oxygen therapy cannot restore it.

Potential warning findings include:

• Increasing pallor
• Dusky, blue, or violaceous discoloration
• Persistent coolness
• Delayed capillary refill
• Progressive edema
• Blistering or epidermal separation
• Loss of adherence to the wound bed
• Fluid collecting beneath the graft
• Malodor or purulent drainage
• Darkening tissue
• Failure to demonstrate expected vascularization
• Expanding areas of necrosis

Color alone is not always reliable. A graft may appear pale during the earliest phase before vascular flow is fully established. A congested graft may appear dark even though some tissue remains viable. Clinical interpretation should consider timing, temperature, adherence, bleeding characteristics, drainage, infection, and the condition of the wound bed.

Serial photographs and consistent documentation can help distinguish normal postoperative evolution from progressive compromise.

Surgical Evaluation Comes Before HBOT

A threatened graft requires prompt evaluation by the surgeon or reconstructive team. Correctable causes should be addressed immediately.

Potential interventions include:

• Evacuating a hematoma
• Draining a seroma
• Removing a constricting dressing
• Reapplying an appropriate bolster
• Correcting graft displacement
• Debriding devitalized tissue
• Treating infection
• Improving arterial inflow
• Relieving venous congestion
• Revising the wound bed
• Returning the patient to the operating room

A graft that is floating on blood or fluid cannot reliably establish vascular contact. HBOT may increase oxygen availability, but it cannot press the graft back against the recipient bed.

Similarly, HBOT cannot overcome an untreated arterial occlusion or a wound bed that is structurally incapable of supporting graft uptake. The treatment becomes most relevant after remediable causes have been corrected and viable tissue remains at risk.

How HBOT May Support a Compromised Graft

During HBOT, the patient breathes oxygen while exposed to increased atmospheric pressure. The treatment raises arterial oxygen tension and substantially increases the amount of oxygen dissolved directly in plasma.

This oxygen-rich plasma can move through functioning vessels in the wound bed and create a stronger diffusion gradient into the graft. That effect may be especially useful during the early period when the graft has not yet developed an independent circulation.

Potential benefits include:

• Increased oxygen diffusion from the recipient bed
• Support for cellular metabolism during plasmatic imbibition
• Improved fibroblast activity
• Support for collagen formation
• Enhanced capillary ingrowth
• Promotion of angiogenic signaling
• Reduction of edema through hyperoxic vasoconstriction
• Improved oxygen-dependent leukocyte microbial killing
• Modulation of ischemia-reperfusion injury

Reviews of compromised grafts and flaps describe increased tissue oxygenation, neovascularization, fibroblast support, and reduction of ischemia-reperfusion injury as important mechanisms through which HBOT may improve salvage. (PubMed Central (PMC))

These effects depend on some remaining perfusion. HBOT cannot deliver a clinically meaningful oxygen dose into tissue that has no functioning vascular access.

Oxygen Diffusion During the Early Graft Period

The temporary lack of direct circulation makes a newly placed graft particularly dependent on diffusion.

Under ordinary atmospheric conditions, oxygen delivery into a hypoxic wound bed may be inadequate because of edema, microvascular injury, radiation damage, or arterial disease. Increasing dissolved plasma oxygen strengthens the gradient between the wound bed and the graft.

This may help maintain marginal cells until vascular connections mature. It may also support the recipient bed, where endothelial cells, fibroblasts, leukocytes, and extracellular matrix must work together to secure and vascularize the graft.

HBOT does not make the graft independent of its wound bed. It temporarily improves the oxygen environment in which graft adherence and revascularization must occur.

Edema Control and Graft Adherence

Edema can compromise graft survival by increasing diffusion distance and reducing microvascular blood flow. Swelling may also contribute to mechanical separation between the graft and recipient surface.

Hyperoxic vasoconstriction can reduce blood flow volume in selected tissues while the elevated oxygen content of plasma helps preserve oxygen delivery. This combination may reduce edema without creating the degree of tissue hypoxia that ordinary vasoconstriction might produce.

The practical objective is not merely to make the wound look less swollen. It is to improve the relationship between capillaries, the recipient bed, and the graft.

Edema control should still include appropriate elevation, dressing selection, treatment of venous obstruction, and correction of any constricting or mechanically disruptive factor.

HBOT and Infection Risk

Bacterial contamination and infection can interfere with graft adherence, damage the recipient bed, and increase local oxygen demand.

HBOT may support oxygen-dependent microbial killing by neutrophils and enhance the activity of selected antimicrobial agents. These effects may improve the local defense environment, but HBOT is not a replacement for infection management.

Treatment may still require:

• Drainage
• Debridement
• Deep tissue cultures
• Culture-directed antibiotics
• Removal of infected material
• Management of systemic sepsis
• Delayed regrafting after infection control

A graft covering an inadequately controlled infection is unlikely to survive solely because tissue oxygenation has increased.

Previous Radiation Increases Graft Risk

Radiated tissue may become fibrotic, hypovascular, and chronically hypoxic. Small-vessel damage can progress for years after radiation treatment, leaving the wound bed with limited capacity to support graft uptake.

When graft compromise occurs within a radiation field, the patient may have overlapping hyperbaric indications:

• Preservation of a compromised graft
• Treatment of soft tissue radionecrosis
• Treatment of osteoradionecrosis when bone is involved

The clinical team should also evaluate for recurrent malignancy, infection, exposed bone, fistula, and other causes of tissue breakdown.

HBOT may improve oxygenation and stimulate vascular remodeling in viable irradiated tissue, but it does not remove necrotic tissue or eliminate the need for appropriate oncologic and reconstructive evaluation.

When to Begin HBOT

Timing matters. HBOT is most biologically plausible while graft tissue is hypoxic but still viable.

The hyperbaric team should be contacted when compromise is recognized, not only after the graft has become black, dry, and clearly necrotic. Delaying consultation may reduce the amount of tissue that can be preserved.

A practical sequence is:

1. Identify signs of graft compromise.
2. Notify the operating or reconstructive surgeon.
3. Correct hematoma, seroma, pressure, displacement, infection, or vascular obstruction.
4. Determine whether viable tissue remains.
5. Begin HBOT promptly when the graft is still considered salvageable.
6. Reassess the graft and wound bed throughout treatment.
7. Return to surgery if progressive necrosis or another correctable problem develops.

The chamber schedule should accommodate surgical care. A necessary operation should not be postponed to complete an HBOT session.

Selecting Patients for Hyperbaric Treatment

HBOT may be considered when:

• A graft is clinically compromised rather than merely at theoretical risk
• Hypoxia or impaired perfusion is contributing to failure
• Mechanical causes have been corrected
• The recipient bed retains some blood supply
• The graft contains tissue that remains potentially viable
• Salvage would reduce wound size, repeat surgery, or reconstructive complexity
• The patient can be treated safely under pressure
• The surgical and hyperbaric teams can coordinate frequent reassessment

HBOT is less likely to provide meaningful benefit when:

• The graft is healing normally
• The graft is already completely necrotic
• A hematoma or seroma remains untreated
• The graft is detached from the wound bed
• A major arterial obstruction has not been corrected
• An uncontrolled infection requires surgery
• The recipient bed cannot support vascular ingrowth
• Treatment would delay a more urgent intervention

The decision should be based on whether HBOT can plausibly change the clinical outcome, not simply whether a skin graft is present.

HBOT Treatment Protocols

Protocols vary according to the type and severity of compromise, timing, wound cause, and facility practice.

Commonly described regimens use:

• Approximately 2.0 to 2.5 atmospheres absolute
• About 90 to 120 minutes of oxygen exposure
• One or two treatments daily during the initial salvage period
• Transition to once-daily treatment as viability stabilizes
• Continued reassessment rather than a fixed course applied to every patient

Reviews based on UHMS practice recommendations commonly describe twice-daily treatment initially, followed by daily treatment when the graft or flap demonstrates improved viability. The total course depends on the clinical response and may be shorter than courses used for chronic radiation injury or diabetic wounds. (PubMed Central (PMC))

The treatment prescription should be individualized by a qualified hyperbaric physician. More pressure or more treatments do not automatically create better graft survival.

Monitoring Graft Response

The treatment team should define objective salvage goals before beginning HBOT.

Serial assessment may include:

• Graft color
• Temperature
• Capillary refill
• Adherence to the wound bed
• Percentage of viable graft
• Drainage
• Infection findings
• Edema
• Demarcation of necrotic areas
• Need for additional debridement
• Progress toward stable wound coverage

Photographic documentation can help quantify changes over time. The surgeon should remain involved because the significance of color, adherence, and tissue loss depends on the graft type, recipient site, operation, and expected reconstructive outcome.

Meaningful benefit may include:

• Increased percentage of graft uptake
• Prevention of further graft loss
• Reduction in the area requiring regrafting
• Preservation of coverage over exposed structures
• Avoidance of a more complex flap procedure
• Earlier progression to stable wound closure

A graft should not be described as salvaged merely because it appears temporarily pinker during oxygen exposure. The improvement should persist outside the chamber and translate into durable tissue survival.

Evidence Supporting HBOT

The evidence base includes animal studies, physiologic research, clinical series, reviews, and a limited number of controlled trials.

A 2017 review concluded that HBOT may increase composite graft survival, improve skin graft outcomes, and support compromised flap salvage. The authors also emphasized the importance of correcting mechanical causes and initiating treatment promptly after compromise is recognized. (PubMed Central (PMC))

A 2020 UHMS review similarly described supportive basic science and clinical evidence across several graft and flap types. However, much of the clinical literature consists of case reports, case series, and nonrandomized studies, which are vulnerable to selection bias and inconsistent outcome reporting. (PubMed)

A Cochrane review of HBOT for acute surgical and traumatic wounds found that the available trials were small and at risk of bias. One study suggested improved split-skin graft survival in burn wounds, while other studies did not establish consistent benefit. The review concluded that high-quality evidence was insufficient for broad routine use. (PubMed Central (PMC))

More recently, a 2025 randomized trial involving 64 adults undergoing split-thickness grafting for traumatic wounds reported higher mean graft uptake with HBOT on postoperative days 4 and 7. Mean graft uptake on day 7 was approximately 91.7 percent in the HBOT group and 83.1 percent in the standard-care group. Donor-site healing was also faster in the HBOT group. (PubMed)

That trial strengthens the evidence that HBOT can influence graft uptake in selected traumatic wounds. It does not prove that every uncomplicated graft should receive routine treatment, nor does it directly answer every question about rescuing a graft after compromise has already developed. The population, wound cause, treatment protocol, and resources available must be considered before generalizing the results.

Routine Prophylactic HBOT Is Not the Standard

UHMS guidance states that HBOT is neither necessary nor recommended for normal, uncompromised grafts and flaps. (UHMS)

A newly placed graft may be clinically important without being compromised. Routine postoperative HBOT would expose many patients to treatment burden and risk without clear evidence of added benefit.

Selective preoperative or immediate postoperative treatment may sometimes be considered when the recipient bed is predictably high risk, such as severely irradiated tissue or a reconstruction with very limited options. In these circumstances, the indication should be documented precisely. The rationale is tissue hypoxia or a recognized radiation injury, not simply the presence of a graft.

The 2025 randomized trial may encourage further research into planned perioperative treatment for high-risk traumatic grafts. It should not be used to justify automatic HBOT after every split-thickness graft. (PubMed)

Medicare Coverage and Medical Necessity

Medicare’s national coverage determination includes the preparation and preservation of compromised skin grafts. It specifically clarifies that HBOT is not covered under this indication for the primary management of wounds. (Centers for Medicare & Medicaid Services)

Documentation should therefore establish:

• That a graft is present or being prepared in a clinically appropriate setting
• Why the graft is compromised
• The evidence of hypoxia, ischemia, or impaired viability
• Corrective surgical measures already performed
• The specific objective of HBOT
• Serial evidence of response
• Continued coordination with the reconstructive team

Payer policies differ. Prior authorization, diagnosis coding, treatment limits, and documentation requirements should be verified for each patient.

Coverage should not determine clinical judgment, but weak documentation can create both reimbursement and compliance risk.

Standard Graft Care Must Continue

HBOT supports the wound environment but does not replace meticulous graft management.

The care plan may still include:

• Appropriate graft fixation
• Bolster or negative-pressure therapy
• Control of fluid beneath the graft
• Immobilization
• Pressure protection
• Limb elevation
• Infection management
• Vascular assessment
• Glucose management
• Nutritional support
• Tobacco and nicotine cessation
• Timely dressing changes
• Surgical debridement

Negative-pressure wound therapy may improve graft contact, remove fluid, and reduce shear in selected wounds. HBOT and negative-pressure therapy address different barriers and may be used together when clinically appropriate.

Nutrition is also important. A patient with inadequate protein, calories, vitamins, or trace elements may have impaired collagen production, immune activity, and epithelial repair despite improved oxygenation.

Tobacco and Nicotine Exposure

Tobacco smoke exposes tissue to carbon monoxide and other substances that interfere with oxygen transport and vascular function. Nicotine can produce vasoconstriction and may further compromise blood flow to a vulnerable wound bed.

Patients should receive clear cessation counseling rather than being told simply that smoking is discouraged. Continued exposure may undermine both the graft and the physiologic objective of HBOT.

The hyperbaric team should also follow strict facility policies regarding smoking, ignition sources, clothing, dressings, and skin products. The FDA advises hyperbaric facilities to follow device instructions, maintain fire-prevention systems, train staff, monitor patients continuously, and control materials introduced into the chamber environment. (U.S. Food and Drug Administration)

Risks of HBOT

HBOT is generally well tolerated when delivered in an appropriately staffed medical facility, but it is not risk free.

Potential adverse effects include:

• Middle-ear or sinus barotrauma
• Confinement anxiety
• Temporary visual changes
• Blood glucose instability
• Pulmonary pressure injury
• Rare oxygen-induced seizure

Middle-ear barotrauma is among the most common complications. Oxygen-related neurologic and pulmonary effects are less frequent under standard protocols but remain important considerations. (PubMed)

An untreated pneumothorax is generally considered an absolute contraindication. Pulmonary disease, seizure history, implanted devices, medication effects, and difficulty equalizing ear pressure require individualized assessment.

The treatment burden should also be considered. Patients may need frequent chamber sessions while continuing surgical follow-up, dressing care, antimicrobial therapy, and rehabilitation.

When Graft Loss Still Occurs

Not every compromised graft can be salvaged. The original injury may be too severe, the recipient bed may remain inadequate, or too much tissue may already be necrotic before treatment begins.

When graft loss occurs, the next step may involve:

• Debridement
• Local wound care
• Regrafting
• Dermal substitute placement
• Local or regional flap coverage
• Free-tissue transfer
• Delayed reconstruction
• Healing by secondary intention

HBOT may still reduce the total area of graft loss even when complete salvage is not achieved. Preserving a portion of the graft can simplify the next operation or reduce the amount of exposed tissue.

Treatment should not continue indefinitely when serial assessment shows progressive necrosis and no meaningful response. The hyperbaric and surgical teams should agree on discontinuation criteria before the course becomes open ended.

Coordinating Graft Salvage

The strongest approach is an integrated reconstructive and hyperbaric pathway:

1. Identify compromise early.
2. Assess the graft and recipient bed urgently.
3. Correct hematoma, fluid, infection, pressure, displacement, or vascular obstruction.
4. Determine whether the tissue remains viable.
5. Begin HBOT promptly when hypoxia is contributing to a salvageable graft.
6. Continue standard graft care and surgical reassessment.
7. Measure viable graft area and durable uptake.
8. Stop or revise treatment when the objective has been achieved or further salvage is no longer realistic.

HBOT is not a substitute for surgical judgment. Its role is to increase oxygen delivery and support the biologic processes needed for a threatened graft to survive.

For the right patient, early treatment may preserve wound coverage, reduce the amount of tissue requiring regrafting, and avoid a more complex reconstructive procedure. Its use should remain selective, time sensitive, and tied to objective evidence that viable tissue is being preserved.