A skin graft or flap that starts to fail in the first days after surgery is a salvage situation. HBOT is one of the few add-on tools with FDA recognition for this use.
This page lays out the evidence for HBOT in graft and flap salvage, the surgical context that drives use, and where the data is strongest.
Quick Facts
| Field | Value |
|---|---|
| FDA approval status | Recognized indication (one of 14) |
| UHMS classification | Tier 1 — approved indication |
| Typical protocol | 2.0-2.4 ATA, 90 min, 2 sessions/day for 2 days, then daily 10-20 sessions |
| Medicare coverage | Covered under LCD L33532, 2025 for compromised tissue |
| Insurance prior auth | Often urgent; surgical compromise must be documented |
| Evidence grade | GRADE B-C (large case series, animal data, no large RCT) |
The evidence
The graft and flap HBOT data rests on a 40-year line of case series, no large randomized trial.
The Bowersox 1986 case series in Hyperb Oxy is the anchor early study. The series of 105 patients with poor blood flow grafts or flaps reported a 90% salvage rate with HBOT. That number is still cited as the strongest pre-modern data point.
The Friedman 2006 review in Plast Reconstr Surg pooled the case series base. The pattern supported HBOT in tissue with poor wound bed oxygen.
The Roje 2008 review on HBOT in plastic surgery reaffirmed the role of HBOT in salvage of failing grafts.
A PMC 2017 review on HBOT for the compromised graft or flap examined the modern evidence base. The conclusion was that HBOT improves salvage rates in well-selected cases, mainly those with poor wound bed blood flow.
The Friedman effect-of-HBOT analysis in PMID 22908842, 2012 examined outcomes across a center experience. HBOT salvage outpaced standard care in pre-radiated and low-blood-flow wound beds.
The Springer compromised graft chapter, 2006 review restated the UHMS framework for graft and flap salvage.
A 2014 PMC study on preconditioned HBOT in animal flap models showed that HBOT before surgery reduced reperfusion injury. That work supports the mechanism but is not direct clinical evidence.
The StatPearls 2024 reference on hyperbaric therapy for skin grafts and flaps sums up current standard of care.
The UHMS chapter on compromised grafts and flaps lays out the formal indication. The Society backs HBOT for tissue compromise from poor blood flow, prior radiation, or low oxygen wound beds.
The case series in PMID 22670552, 2012 reported on flap salvage after mastectomy reconstruction. HBOT salvaged a flap heading for failure when started in the first 48 hours.
The pattern across 40 years is steady. HBOT salvages tissue in graft and flap cases with poor wound bed conditions when started right after surgery. The data is large case series, not large randomized.
Mechanism of action
A graft or flap survives by getting oxygen from the wound bed below or from new blood vessels that grow into the tissue. When either source fails, the tissue starts to die.
The Bowersox-era work mapped the oxygen problem. Tissue at the boundary between living and dying graft has measurably low oxygen. Without enough oxygen, fibroblasts cannot lay down new collagen and new blood vessels cannot grow in.
Hyperbaric oxygen raises plasma oxygen high enough to feed the tissue by diffusion, even when blood flow is poor. The dissolved oxygen keeps the at-risk tissue alive while normal blood flow is built back.
HBOT also drives new blood vessel growth into the wound bed. This is the same angiogenesis effect Marx mapped for radiation-damaged tissue. The new vessels make the graft or flap take root over the next weeks.
HBOT also blunts the reperfusion injury that follows ischemia. When blood flow returns to oxygen-starved tissue, a wave of free radicals can kill cells; oxygen breathing under pressure changes that response.
The mechanism explains the tight time window. Tissue that has been dead for more than 48 hours cannot be brought back, no matter the chamber dose.
Typical protocol
The standard plan is 2.0 to 2.4 ATA for 90 minutes. The first 48 hours often run 2 sessions per day, then daily for 10 to 14 more sessions.
Total session counts run 10 to 20. The course is much shorter than the wound or bone infection plans.
Treatment starts as soon as the surgical team flags the graft or flap as failing. Color change, capillary refill failure, or doppler signal loss are the usual triggers.
The Friedman framework supports starting HBOT within 24 hours of the first signs of compromise. Delay past 72 hours sharply cuts the salvage chance.
Insurance and cost
Medicare covers compromised grafts and flaps under CMS NCD 20.29, 2017 and the related LCD L33532. Cover asks for proof that the graft or flap is failing, with notes from the surgical team.
Cost per session runs $250 to $500. A 10 to 20-session course at retail rates is $2,500 to $10,000.
Commercial insurance follows Medicare in most cases. Prior auth is often expedited because of the salvage time pressure. Plans often process these claims within hours rather than days.
Many post-op patients are still inpatient when HBOT begins. The treatment cost is folded into the surgical care bill, and patients face no separate out-of-pocket question.
Where to get it
Graft and flap HBOT runs at hospital-based hyperbaric centers attached to surgical hospitals. Outpatient wound centers handle some cases, but most failing grafts and flaps need urgent in-hospital care.
The UHMS-accredited facility directory, current 2026 lists qualified centers. Most US metro areas have at least one site able to deliver urgent post-op care.
For chamber type details, see our FDA-cleared chambers list. Graft salvage asks for medical-grade chambers reaching 2.0 ATA or higher.
The geography matters because the time window is small. A patient in a small rural hospital with a failing flap may need to be moved to a larger center with HBOT capacity. Transfer time eats into the salvage window.
See our UHMS accreditation primer for what the credential means.
Limitations and contraindications
The 48 to 72-hour window from first signs of compromise is the main practical limit. After that, the tissue is mostly dead and HBOT cannot save it.
Untreated lung collapse is an absolute limit. So is unstable arrhythmia or active seizure disorder.
Patients with severe lung disease may not tolerate the urgent twice-daily plan. The condensed course is harder on lungs than the daily wound-care plan.
Patients with diabetes need close blood sugar checks. Chamber sessions lower blood sugar, and dose tweaks are normal.
The harder limit is what HBOT cannot fix. A flap that has lost its arterial supply because of a surgical kink in the pedicle needs surgical revision, not oxygen. HBOT helps tissue with poor but not absent blood flow, and it cannot bring back tissue with no blood flow at all.
Active research
ClinicalTrials.gov studies on graft and flap HBOT, current 2026 cover plans for breast reconstruction flaps, head and neck flaps, and lower-extremity grafts.
A focus area is preconditioning. Some trials test whether HBOT before high-risk surgery cuts the rate of post-op flap loss in pre-radiated patients.
Another focus is the role of HBOT after free-tissue transfer, where microvascular anastomosis failure is a known problem.
How this compares to off-label HBOT uses
Compromised grafts and flaps sit in the middle of the evidence range for FDA-listed HBOT uses. The mechanism is well mapped, the case series are large, but no large randomized trial has been done.
This is very different from off-label HBOT for general wound healing or chronic recovery. Graft salvage targets a clear surgical failure with a well-defined time window. Off-label wound use does not target such a clear failure.
For context on how off-label HBOT marketing splits from clinical data, read our analysis of institutional silence on HBOT and our diabetic foot ulcer evidence atlas, where the wound bed oxygen framework applies in a related way.
The honest summary: HBOT for graft and flap salvage is a settled add-on with real case series support. It is not a substitute for good surgical planning, and it cannot save tissue that has lost its blood supply outright.
Frequently asked questions
How fast does treatment need to start?
The strongest evidence backs starting within 24 hours of the first signs of compromise. Many centers still treat between 24 and 72 hours but expect smaller salvage rates. After 72 hours the case for HBOT in graft salvage becomes thin.
Is HBOT a substitute for surgical revision?
No. A flap with a kinked or thrombosed pedicle needs surgical revision. HBOT helps tissue with poor wound bed oxygen, not tissue with no blood flow at all. Surgery and HBOT often run together.
Which patients respond best?
Patients with pre-radiated wound beds, poor blood flow grafts, or compromised flaps respond best. Bowersox reported 90% salvage in his series, most of whom had risk factors that made graft failure likely.
Will Medicare cover this?
Yes for documented compromised tissue under LCD L33532. Cover is usually straightforward when surgical notes flag the graft or flap as failing. Prior auth is often expedited because of the time window.
Can a soft-shell wellness chamber treat this?
No. Graft salvage HBOT asks for 2.0 to 2.4 ATA in a medical chamber. Soft-shell chambers reach only 1.3 ATA and do not deliver the tissue oxygen needed for salvage.
Sources
- Bowersox Case Series, 1986
- Friedman Plast Reconstr Surg Review, 2006
- Roje Plastic Surgery Review, 2008
- PMC Compromised Graft Review, 2017
- Friedman Effect Analysis, 2012
- Springer Compromised Graft Chapter, 2006
- PMC Preconditioned HBOT Animal Study, 2014
- StatPearls Skin Graft Hyperbaric Therapy, 2024
- UHMS Compromised Grafts and Flaps Chapter, current
- Mastectomy Flap Salvage Case, 2012
- CMS NCD 20.29 Hyperbaric Oxygen Therapy, 2017
- CMS LCD L33532, 2025
Medical disclaimer
This page is medical journalism, not medical advice. A failing graft or flap is a surgical urgency that should be evaluated by the operating team. HBOT is one add-on in a layered salvage plan that may include surgical revision. Talk to a plastic or reconstructive surgeon about care choices.