Hyperbaric oxygen therapy in South Africa : review

Hyperbaric oxygen therapy (HBO) is the use of 100% oxygen, breathed under pressure and delivered to tissues by the circulation, to achieve a therapeutic benefit. Under hyperbaric conditions oxygen attains medicinal properties. Time and pressure of the exposure provide the specific "dose" and "tissue level" required to achieve the effect. HBO provides a pressure-related increase in plasma-borne oxygen. This increases total blood oxygen content by 20-25% and markedly improves free (i.e. dissolved) oxygen delivery to tissues, increasing the diffusion distance from the capillaries into tissues several fold. At these increased tissue levels, oxygen initiates a series of distinct physiological and pharmacological effects.