Physician Referral Guide: Hyperbaric Oxygen for Compromised Skin Grafts and Flaps

Assessing the patient before referral

While arranging hyperbaric assessment in coordination with the surgical team, the referring service should:

• Document the timeline precisely: date and time of the index operation, the type of reconstruction (split- or full-thickness graft, local, regional, or free flap), and the time of onset of the compromise. The interval since surgery determines whether the patient is still inside the salvage window.
• Examine and record the perfusion status of the graft or flap: colour, capillary refill, temperature, turgor, and any venous congestion or arterial insufficiency. A serial description helps the hyperbaric team judge trajectory.
• Exclude a correctable surgical cause in consultation with plastic surgery, since re-exploration may need to precede HBOT.
• Review the recipient-bed history, especially prior radiation, prior surgery, infection, diabetes, smoking, or peripheral vascular disease, all of which raise the risk of failure.
• Screen for hyperbaric contraindications and ear or sinus barotrauma risk (see below), and confirm the patient can tolerate lying in a chamber for roughly 90 minutes per session.

What the evidence supports

The Undersea and Hyperbaric Medical Society classifies this indication at Level B (moderate evidence), reflecting support from controlled studies alongside clinical experience. The underlying randomised evidence is limited. A Cochrane review of HBOT for acute surgical and traumatic wounds (Eskes et al. 2013) found that two small trials suggested HBOT may improve the outcomes of skin grafting and trauma, but judged those trials to be at risk of bias and concluded that high-quality randomised trials are still needed. The benefit for compromised grafts and flaps should therefore be understood as plausible but not firmly established by high-quality trial evidence. The Canada Hyperbarics research database holds 140 peer-reviewed studies on this indication. You can read the vetted clinical overview on the compromised skin grafts and flaps condition page.

The mechanistic rationale is well established and is consistent with the observational and trial signal. At 2.0 to 2.5 ATA on 100 percent oxygen, plasma oxygen content rises markedly, raising tissue oxygen tension at the graft-wound interface and sustaining aerobic metabolism in marginally perfused tissue. Hyperoxic vasoconstriction can reduce capillary permeability and oedema while oxygen delivery to hypoxic tissue is preserved. Over a course, HBOT is thought to support VEGF-mediated angiogenesis and fibroblast proliferation, helping the graft or flap establish definitive vascularisation.

A consistent practical theme across the literature is timing. The biological window for post-operative HBOT is generally regarded as the first 24 to 72 hours after the index operation, and earlier intervention is associated with better salvage rates. In the pre-operative setting for irradiated beds, the Marx protocol of 20 HBOT sessions before the planned graft or flap and 10 sessions afterward has been described as a way to improve the vascularity of the recipient bed before reconstruction proceeds. The evidence does not establish HBOT as a guaranteed rescue, and it does not replace sound surgical technique or re-exploration; it is best understood as an adjunct intended to improve the odds for tissue at risk.

The Canadian referral pathway

Compromised grafts and flaps are treated as a semi-urgent indication at Canadian hospital-based hyperbaric programmes and are covered by provincial health insurance. Referral is normally coordinated between the plastic-surgery service and the nearest hospital hyperbaric programme. If a patient with acute compromise presents to an emergency department without an established pathway, the receiving department coordinates transfer to the nearest hospital hyperbaric programme.

• Ontario: programmes at Toronto General (UHN), Hamilton General, and The Ottawa Hospital. For urgent inter-hospital coordination, CritiCall Ontario at 1-800-668-4357 connects emergency departments to these programmes and arranges transport when needed.
• British Columbia: Vancouver General Hospital (Leon Judah Blackmore Pavilion), the only hospital chamber in the province; covered under MSP.
• Alberta: Misericordia Community Hospital (Edmonton) or Foothills Medical Centre / Arthur J.E. Child Comprehensive Cancer Centre (Calgary); covered by Alberta Health.
• Quebec: RAMQ covers Hopital du Sacre-Coeur de Montreal and Hotel-Dieu de Levis.
• Nova Scotia, and Newfoundland and Labrador: hospital-based programmes serve these provinces.
• Saskatchewan: a hospital-based programme provides access in-province.
• Provinces and territories without a hospital programme: referral is arranged to the nearest accepting hospital programme in coordination with the surgical and hyperbaric teams.

Because the salvage window is short, telephone the receiving hyperbaric programme early to confirm capacity and timing rather than waiting for a formal written referral to be processed.

How to use the research list below

The list contains every compromised-grafts-and-flaps study in the Canada Hyperbarics database that was published in 2020 or later and has a freely available full-text version, each linked directly to that full text. Paywalled and abstract-only studies are excluded, and retracted studies are removed. This is a reference list, not a set of summaries. Counts and the open-access set refresh each quarter.