Physics and Physiology
Hyperbaric Oxygen Therapy – The Science
‘Hyper‘ means more AND ‘Baric‘ refers to pressure.
Hyperbaric Oxygen Therapy is often referred to as “HBO” or “HBOT”.
How does Hyperbaric Oxygen Therapy (HBOT) work?
Air contains approximately 21% oxygen and 78% nitrogen. During HBOT the oxygen percentage breathed by the patient is increased to 100%, i.e. almost five times more than in air.
The pressure of the oxygen breathed by the patient in HBO is 2 to 3 times greater than atmospheric pressure (most often 2.4 atmospheres or bar). This means that during HBOT the patient is breathing 10 to 15 times more oxygen than they would be when breathing air at normal pressure.
During treatment oxygen is breathed through the lungs, dissolved in the blood plasma, and transported around the body via the blood supply. Even where the blood supply is poor, the high levels of oxygen dissolved in the plasma provide significantly elevated levels. The effects of these very high levels of oxygen vary according to the type of tissue they reach and the underlying condition that has for which HBOT is being given.
What are the effects of Hyperbaric Oxygen Therapy?
Some of the effects include:
- Improved white blood cell function
- reduction of inflammation / swelling
- development and growth of new blood vessels (neoangiogenesis)
- increased bone growth and bone repair
- improved antibiotic activity
- increased collagen deposition and improved ligament and tendon repair
- compression of gas bubbles
- suppression of toxin production (important in some infections such a necrotising fasciitis)
- increased circulation of stem cells from bone marrow.
It is important to note that although these effects are established in the scientific literature it may not mean that HBOT will help your specific condition, and it is important to consider clinical trials.
Is Hyperbaric Oxygen Therapy a Medicine?
HBO is like any other medicine or drug, with indications, contra-indications and potential side-effects. An appropriately qualified physician needs to ensure HBOT is appropriately prescribed, as it is possible for the high levels of oxygen or the pressure to cause harm. British Hyperbaric Association member chambers all use suitably qualified doctors to be able to give you appropriate advice regarding this.