Hyperbaric Chamber: What It Does and Who It Helps

A Hyperbaric Chamber Treats Conditions Ranging from Chronic Wounds to Decompression Sickness

A hyperbaric chamber treats conditions ranging from chronic wounds to decompression sickness by flooding tissues with oxygen at up to three times normal atmospheric pressure, a level haemoglobin alone cannot achieve. The chamber is a sealed vessel that raises the air pressure around you, typically to 1.5 to 3 times normal atmospheric pressure, while you breathe oxygen at high concentration. At that pressure, oxygen dissolves directly into your plasma, reaching tissues that are starved of supply regardless of how well your red blood cells are performing.

This post focuses on who benefits, what the evidence actually says, and how to access a session in Cardiff without a long wait. For the full science and different chamber types, see What Is a Hyperbaric Chamber?.

Why Oxygen Under Pressure Does Something That Breathing Normally Cannot

At sea level, haemoglobin saturation is typically around 95 to 99 percent, depending on the individual (British Thoracic Society pulse oximetry guidance). Breathing harder does not push much more oxygen in. Pressure changes that equation. Under hyperbaric conditions, oxygen dissolves into the liquid part of your blood, reaching tissues with poor circulation or damaged blood vessels.

Research suggests this local surge in oxygen can:

• Stimulate new blood vessel formation (angiogenesis)
• Reduce inflammation in damaged tissue
• Support white blood cell activity against certain infections
• Accelerate collagen production in healing wounds

The hyperbaric oxygen therapy benefits post goes through the clinical evidence category by category, so you can see what is well-supported and what is still emerging.

Who Has the Strongest Evidence Behind Them

Hyperbaric oxygen therapy (HBOT) has a long track record in specific medical conditions. The clearest evidence sits in:

Decompression sickness. The original use. Divers who surface too quickly develop nitrogen bubbles in the blood, and a hyperbaric chamber is the definitive treatment, as recognised by the Undersea and Hyperbaric Medical Society (UHMS).

Carbon monoxide poisoning. High-pressure oxygen displaces carbon monoxide from haemoglobin far faster than breathing room air, a mechanism supported by Cochrane review evidence.

Diabetic foot ulcers and chronic wounds. Multiple controlled trials show improved healing rates in wounds with poor blood supply, and NICE guidance on wound management acknowledges adjunctive oxygen therapy in selected cases.

Radiation tissue injury. Patients who develop tissue damage after cancer radiotherapy often respond well to a course of HBOT, based on published trial data reviewed by the UHMS.

Beyond those established uses, there is growing interest in HBOT for long COVID fatigue, post-surgical recovery, sports performance, and general energy. A 2022 randomised controlled trial published in PLOS ONE (Efrati et al.) reported improvements in cognitive and fatigue symptoms in long COVID patients receiving HBOT, though larger replication studies are needed. The safety profile is well-established and the physiological rationale is supported by the plasma-dissolution mechanism described above. See HBOT for athletes for a closer look at the recovery angle.

The evidence, by indication

What to ask an HBOT provider

1. Who assesses whether it is safe for me, and are they medically registered?
2. What pressure do you run, and for how long?
3. What do you screen for? Untreated pneumothorax and some lung and ear conditions rule people out.
4. What is the evidence for the specific reason I am coming? If it is limited, you should be told so.
5. What would make you turn me away?

The NHS, Private Access, and What That Means in Wales

NHS hyperbaric oxygen therapy in Wales is available, but access is narrow. It is generally restricted to the established indications above, and referral pathways can be slow. For people who want HBOT for fatigue recovery, post-illness support, or as a complement to iron treatment, the NHS route is rarely practical.

Private access changes that picture. At IronOx Clinic in Cardiff, you do not need a GP referral, and your first session can be booked around your schedule. For current session pricing and package options, see our iron infusion Cardiff page, where HBOT packages are listed alongside iron infusion options. Prices are correct at time of publication and subject to change.

For a broader comparison of NHS and private pathways, the post Does the NHS Offer Hyperbaric Oxygen Therapy? sets out what each route involves.

Why Iron Deficiency and HBOT Are Often Treated Together at IronOx

This is something we see regularly in Cardiff. A patient arrives exhausted, with confirmed low ferritin, and wants to know whether HBOT will help. It can, but only if the underlying iron deficiency is corrected at the same time.

Ferritin is your body's iron storage marker, and it is the most relevant blood value to check before starting HBOT. Low ferritin means your bone marrow cannot produce enough haemoglobin to carry oxygen efficiently, even if HBOT is raising the oxygen dissolved in your plasma. NICE CKS guidance on iron deficiency anaemia confirms that ferritin is the primary diagnostic marker for depleted iron stores.

At IronOx, we use ferric carboxymaltose for iron infusions. Ferric carboxymaltose is a high-dose intravenous iron formulation that can replenish iron stores in a single appointment, rather than requiring weeks of oral supplementation. NICE guidance (NG8) on intravenous iron in anaemia management supports its use where oral iron is insufficient or not tolerated. Correcting iron stores with ferric carboxymaltose alongside HBOT gives the therapy the best possible conditions to work. Every IronOx iron infusion package includes one complimentary HBOT session built in (see current packages at /iron-infusion-cardiff).

The iron infusion and HBOT combination post explains the clinical thinking behind pairing the two.

What a Session at IronOx Looks Like

Our Cardiff clinic uses a modern monoplace chamber. You arrive, complete a brief health screen with a clinician, and then spend around 60 minutes in the chamber breathing high-concentration oxygen. The pressure builds gradually over the first few minutes. Most people notice mild ear pressure, the same sensation as descending in a plane, which clears easily by swallowing.

There is no recovery time needed. Most patients leave and carry on with their day.

Is a Hyperbaric Chamber Right for You

If you have a confirmed indication such as a chronic wound, radiation injury, or decompression sickness, HBOT has strong clinical backing. If you are using it for fatigue, recovery, or as part of an iron deficiency treatment plan, the evidence is supportive and the risk profile is low, but realistic expectations matter.

A free telephone consultation at IronOx lets you talk through your situation with a GMC-registered doctor before spending anything. There is no obligation and no card taken at booking.

Reviewed by Dr Ros Jabar, GMC 7265326.