Hyperbaric Oxygen Therapy for Threatened Surgical Flaps
For a threatened surgical flap 6 days post-surgery, hyperbaric oxygen therapy should be initiated immediately as an adjunctive treatment to maximize tissue salvage, with treatment consisting of 90-minute sessions at 2.0-2.5 atmospheres once or twice daily. 1, 2
Evidence Supporting HBO Therapy for Compromised Flaps
The strongest evidence for HBO therapy in threatened surgical flaps comes from clinical outcomes demonstrating high salvage rates when treatment is initiated promptly:
A 2023 study of nipple-sparing mastectomy flaps achieved 88% flap salvage rates using HBO therapy at 2.0 atmospheres for 90 minutes once or twice daily, with mean initiation time of 9.5 days post-surgery. 2 This represents the most recent high-quality evidence directly addressing threatened surgical flaps in the post-operative period.
HBO therapy enhances flap survival through multiple mechanisms: decreasing hypoxic insult, enhancing fibroblast function and collagen synthesis, stimulating angiogenesis, and inhibiting ischemia-reperfusion injury. 3
A 2015 case report demonstrated successful breast flap salvage at 6 days post-surgery using HBO therapy twice daily for 6 days, combined with leech therapy after the first HBO treatment showed incomplete response. 1 This timeline directly parallels your clinical scenario.
Treatment Protocol
Initiate HBO therapy immediately upon recognition of flap compromise:
Administer 90-minute sessions at 2.0-2.5 atmospheres (2.0-2.5 bar O₂), once or twice daily depending on severity of compromise. 1, 2, 4
Continue treatment until clinical improvement is evident, typically 6-10 sessions over 3-7 days for acute flap compromise. 1, 2
The expedient initiation of HBO therapy as soon as flap compromise is identified maximizes tissue viability and ultimately graft/flap salvage. 3
Adjunctive Therapies to Consider
If initial HBO response is incomplete after 1-2 treatments:
Consider adding leech therapy (Hirudo medicinalis) for venous congestion, as the combination provides better outcomes than either modality alone. 1 Apply 2 leeches at a time, 3 times daily, with Aeromonas prophylaxis (ceftriaxone). 1
Topical nitroglycerin and oral pentoxifylline (400 mg three times daily) can be used as additional adjuncts, though nitroglycerin should be discontinued if leech therapy is initiated. 1
Physiologic Rationale
HBO therapy delivers 100% oxygen at 2-3 absolute atmospheres, achieving much higher concentrations of dissolved oxygen in blood and resulting in higher tissue oxygen tensions. 5
At these elevated tissue oxygen tensions, beneficial effects include:
- Improved leukocyte function 5
- Enhanced antibiotic activity 5
- Accelerated vascular regeneration, with significant increases in microcirculation demonstrated by days 7-11 post-operatively 4
Critical Caveats
HBO therapy should never delay or replace standard surgical management:
HBO is an adjunctive therapy only and must not interfere with standard treatment. 5
Patients should not be transferred to distant facilities for HBO if this delays necessary surgical intervention or debridement. 5
Monitor for HBO-related complications including ear pain (common, 17.6% in one series) and sinus pressure (rare but may require treatment abortion). 2
Limitations of Current Evidence
While guidelines primarily address HBO for necrotizing infections and diabetic foot ulcers, the evidence base for compromised surgical flaps relies on case reports and small case series rather than randomized controlled trials. 5, 3 However, the consistent positive outcomes across multiple reports, combined with the low risk profile and strong physiologic rationale, support its use in this clinical scenario where flap loss would result in significant morbidity requiring revision surgery.
The 2024 ACC/AHA guidelines rate HBO therapy for CLTI wounds as "may be considered" (Class 2b, Level B-NR), reflecting moderate evidence quality. 5 This conservative recommendation applies to chronic wounds rather than acute post-operative flap compromise, where the evidence and clinical urgency support more aggressive intervention.