How Does HBO Work?

Hyperbaric Oxygen Therapy (HBO) is defined as a treatment mode in which the patient is entirely enclosed in a pressure chamber breathing oxygen at a pressure greater than one atmosphere. Breathing 100 % oxygen at one atmosphere (1 ATA) or applying oxygen outside a pressurized chamber are not considered hyperbaric oxygenation.

Hyperbaric oxygen therapy (HBOT) is a conventional medical treatment modality. It involves the use of 100% oxygen, breathed within an environment of increased pressure and delivered to the tissues via the circulation, to achieve a therapeutic benefit. This increases total blood oxygen content by 20% - 25%, but more importantly, it improves free oxygen delivery to tissues. At these increased levels, oxygen initiates a series of physiological and pharmacological effects that can be exploited clinically.

HBOT has been called "the surgeon's friend" as it improves outcomes and can attenuate complications. While Hyperbaric Oxygen Therapy (HBOT) is certainly no substitute for sound surgical practice, even good surgical technique cannot compensate for the physiological deficiencies of a hypoxic, hypo vascular environment. The increased level of awareness and the gratifying results obtained with HBOT have created an increasing appreciation and demand for the therapy.

The earth's atmosphere normally exerts 14.7 pounds per square inch (PSI) of pressure at sea level. That is equivalent to one atmosphere absolute (abbreviated as 1 ATA). In this atmosphere we breathe approximately 20 % oxygen and 80 % nitrogen. During HBOT, the pressure is increased by two to three times the normal and the patient breathes 100 percent oxygen.

The usual arterial partial pressure of O2 is about 100 mm Hg, haemoglobin is 95 % saturated and 100 ml of Blood carries 19 ml of O2 in combination with haemoglobin and 0.32 ml dissolved in plasma. If the inspired O2 concentration is increased to 100 % (at 1 ATA), O2 combined with haemoglobin can increase to a maximum of 20 ml when the haemoglobin is 100% saturated and the amount of O2 dissolved in plasma may increase to 2.09 ml. During HBO in addition to the haemoglobin which is 100% saturated the amount of O2 carried in solution will increase to 4.4 ml % at a pressure of 2 ATA and to 6.8 ml % at 3 ATA, which is almost sufficient to supply the resting total oxygen requirement of many tissues without a contribution from oxygen bound to haemoglobin. It is this increased Oxygen in Plasma which is responsible for most of the beneficial effects of hyperbaric oxygen.

Increased pressure combined with the increase in oxygen content dissolves oxygen into the blood and all other body tissues and fluid at up to 20 times the normal concentration high enough to sustain life even with low Red blood cell levels(which otherwise cannot sustain life!!)