(628) Impact of Hyperbaric Oxygen Therapy on Free Flaps Outcomes for Refractory Osteoradionecrosis: A Scoping Review

Introduction: This review evaluates whether prior exposure to hyperbaric oxygen therapy (HBOT) influences outcomes in patients undergoing vascularized free flap reconstruction for refractory osteoradionecrosis (ORN).

Methods: A systematic scoping review was conducted according to PRISMA-ScR guidelines. PubMed, EMBASE, Scopus, Web of Science, and Cochrane Library were searched from database inception through December 1, 2025. Studies were included if they reported quantitative outcomes comparing HBOT-exposed to non-exposed head and neck cancer patients undergoing free flap reconstruction for refractory ORN. Two independent reviewers conducted screening, full-text review, and data extraction for study design, clinical characteristics, HBOT protocols, and surgical outcomes.

Results: Of 148 studies identified, 4 met the inclusion criteria, including 1 randomized controlled trial and 3 retrospective cohort studies published from 2014-2025. HBOT regimen reporting was inconsistent, with incomplete treatment documentation in two studies. Reported protocols varied: 20-30 pre- and 10 post-operative sessions at 2.4 ATA for 90 minutes. Increased ORN-healing was observed with adjunctive HBOT. No consistent differences were associated with flap survival or postoperative complications. Study heterogeneity, underreporting of flap features, lack of subgroup analyses for comorbidities, and limited statistical power limit the ability to draw definitive conclusions.

Conclusions: HBOT may improve the resolution of refractory ORN, but it does not clearly affect reconstruction outcomes. Standardized HBOT regimens, comprehensive reporting of flap features, and adequately powered prospective studies are needed to define the role of HBOT in optimizing reconstructive outcomes and identifying predictors of improved healing for refractory ORN.