This article is part of the HBOT Radar series, where we summarize the latest published hyperbaric oxygen therapy research.
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Disclaimer: This article is intended for educational and informational purposes only. It summarizes published medical research conducted in clinical settings and does not evaluate Brain Spa Hyperbaric products. The hyperbaric chambers offered on this website are non-medical wellness devices and are not intended to diagnose, treat, cure, or prevent any disease. Do not make medical decisions based on this article — consult a qualified healthcare professional.
📌 Her Leg Ulcer Wouldn't Close for Months. 20 Oxygen Sessions Changed the Math.
🔍 What this study tested
Chronic venous leg ulcers are one of medicine's most stubborn problems. They're open wounds on the lower legs caused by poor vein circulation — blood pools, pressure builds, skin breaks down, and a wound opens that simply refuses to heal. They affect 1-3% of adults, and the numbers are rising as populations age.
The standard treatment is compression therapy — specialized bandages that squeeze the leg to push blood back up. It works for some. But even with proper compression, 30-60% of ulcers remain unhealed after six months. These patients live with open, painful, often infected wounds on their legs for months or years, cycling through dressing changes, clinic visits, and repeated courses of antibiotics.
What makes venous ulcers particularly frustrating is that the underlying problem is clear: the tissue at the wound base is hypoxic — starved of oxygen. Damaged veins can't deliver enough oxygenated blood, and without oxygen, the cascade of healing — cell proliferation, collagen formation, angiogenesis, infection control — stalls.
This is exactly the problem hyperbaric oxygen therapy is designed to solve. And yet, despite decades of clinical use for diabetic foot ulcers, the evidence for HBOT in venous leg ulcers has been surprisingly thin. A Serbian research team set out to change that with a proper randomized controlled trial.
🌬️ HBOT protocol used in this study
- Design: Single-centre, open-label, prospective randomized controlled trial
- Location: University Clinical Center of Vojvodina, Novi Sad, Serbia
- Patients: 80 adults with chronic venous leg ulcers that had persisted for more than 3 months despite standard compression therapy (defined as less than 30% wound area reduction after 4 weeks of compression)
- HBOT group (n=40): 20 sessions at 2.4 ATA, 90 minutes each, plus standard wound care
- Control group (n=40): Standard wound care alone (compression, dressings, wound management)
- Primary outcome: Percentage ulcer area reduction at day 30
- Secondary outcome: Complete healing at day 90
- Assessment: Wound measurements by blinded assessors (they didn't know which group the patient was in)
This study was conducted in a clinical hospital setting under medical supervision. Results from clinical research cannot be directly applied to other settings or devices — always consult a healthcare professional.
📊 Key findings
Wounds shrank 50% faster with HBOT
At day 30, the HBOT group showed 62.1% mean ulcer area reduction compared to 41.7% in the control group (p < 0.001). The effect size was large — Cohen's d = 1.12 — meaning this isn't a subtle difference. It's clinically obvious.
To put it in practical terms: if your wound was 10 cm² at the start, after 30 days with HBOT it was down to about 3.8 cm². Without HBOT, it was still about 5.8 cm². That's the difference between a wound that's clearly closing and one that's barely improving.
Double the complete healing rate at 90 days
The more important number: at 90 days, 62.5% of HBOT patients had completely healed wounds compared to 30% in the control group.
That's a number-needed-to-treat (NNT) of 3. In clinical medicine, NNT = 3 is exceptionally strong — it means for every 3 patients you treat with HBOT, one additional patient heals completely who wouldn't have healed otherwise. Many widely used medical treatments have NNTs in the tens or twenties.
These were the hardest cases
It's worth emphasizing what kind of patients were included: these were refractory ulcers — wounds that had already failed standard compression therapy. Less than 30% area reduction after 4 weeks of compression was the inclusion criterion. These aren't wounds that were going to heal on their own anytime soon. The fact that 62.5% of them healed completely after adding HBOT is all the more striking given how resistant they were to begin with.
🧠 Why this matters
This is NOT the typical diabetic foot ulcer story. Most HBOT wound research focuses on diabetic foot ulcers, where HBOT has been studied extensively and is an accepted indication in many guidelines. Venous leg ulcers are a different condition with a different mechanism — but the oxygen-deprivation problem is similar.
What this trial adds is the first solid RCT evidence specifically for venous leg ulcers, from a credible European university hospital, with blinded wound assessment and hard endpoints (complete healing, not just surrogate markers).
The honest caveats:
- Open-label. Patients knew whether they were getting HBOT. This could introduce performance bias (HBOT patients might take better care of themselves) and placebo effects. However, wound measurements were done by blinded assessors, which mitigates this for the primary outcome.
- Single centre. All patients from one hospital in Serbia. Multicentre replication would strengthen the evidence.
- 80 patients is moderate. Enough for the large effect sizes observed, but a larger trial would be more convincing.
- No sham-HBOT group. The control group didn't receive any chamber time. A sham-controlled design (as in the 2018 Thistlethwaite trial for venous ulcers) would have been ideal, though that earlier trial was hampered by small numbers after excluding responders.
- 2.4 ATA with 100% oxygen. This is clinical-grade HBOT — the results cannot be assumed for lower-pressure protocols.
📌 Takeaway for the community
- A randomized controlled trial of 80 patients with treatment-resistant venous leg ulcers found that adding 20 HBOT sessions nearly doubled the complete healing rate at 90 days — 62.5% vs 30%
- Wound area shrank 62.1% in 30 days with HBOT versus 41.7% without — a large and clinically meaningful difference (Cohen's d = 1.12)
- NNT of 3 means every third patient treated with HBOT healed who wouldn't have otherwise — an exceptionally strong treatment effect
- These were refractory ulcers that had already failed standard compression therapy — the hardest cases
- The trial was open-label (not sham-controlled), which is a limitation, though wound measurements were done by blinded assessors
- This study was conducted at a university hospital in Serbia at 2.4 ATA — results cannot be directly applied to other settings or devices
Source: https://pmc.ncbi.nlm.nih.gov/articles/PMC12932018/
Nikolić D, Pasternak J, Manojlović V, Budinski S, Nikolić MB, Batinić N. Hyperbaric Oxygen Therapy for Chronic Venous Leg Ulcers: A Prospective Randomised Controlled Trial. Int Wound J. 2026;23(3):e70856. doi: 10.1111/iwj.70856.
Educational disclaimer
This content summarizes findings from published medical research for educational purposes only.
The hyperbaric chambers sold on this website are non-medical wellness devices and are not intended to diagnose, treat, cure, or prevent any disease.
The studies discussed here were conducted in clinical medical settings using medical-grade interventions. The inclusion of research summaries does not imply that similar outcomes can be achieved using non-medical wellness devices.
