APPLICATIONS OF HYPERBARIC MEDICINE
Hyperbaric Oxygen Therapy is a treatment mode in which the patient is entirely enclosed in
a pressure chamber breathing 100% oxygen at a pressure greater than one atmosphere.
HBO therapy is the application of oxygen at pressure above atmospheric to a patient who is totally exposed to the increased pressure.
Normal pressure at sea level is 14.7 PSIA, referred to as One Atmosphere Absolute (1 ATA);
pressures between 2 and 3 ATA are normally used in Hyperbaric Oxygen Therapy.
Significant physiological mechanisms, which are activated as a result of hyperbaric oxygenation,
explains the therapeutic results of HBO:
Hyper-Oxygenation: HBO physically dissolves extra oxygen into the blood plasma. The breathing of pure oxygen at three times normal pressure (3 A.T.A.) delivers 15 times as much physically dissolved oxygen to tissues as breathing room air. This promotes formation of new capillaries into wound areas, and sufficient oxygen tensions to meet the needs of ischemic tissues. Hyper-oxygenation effects are provided in the treatment of anemias, ischemias, and some poisonings.
Vasoconstriction: High pressure oxygen causes constriction of the blood vessels (without creating hypoxia) which decreases edema in injured tissues and secondarily decreases intracranial pressure. This effect is useful in burns, crush injuries, and interstitial bleeding. It may also be effective in acute brain and spinal cord injuries.
Mechanical Effect of Increased Pressure: Any free gas trapped in the body will decrease in volume as the pressure on it increases. With a threefold increase in pressure, a bubble trapped in the body is reduced by two-thirds. This reduction in gas volume has been successfully applied to air embolism and decompression sickness.
Mass Action of Gases (gas wash out): The flooding of the body with any one gas tends to "washout" all others. This action occurs more rapidly under pressure than under ordinary conditions, and makes HBO an indicated treatment for carbon monoxide intoxication and acute cyanide poisoning.
Bacteriostatis: HBO inhibits the growth of a number of anaerobic as well as aerobic organisms. This effect also compliments the improved action of host disease-fighting factors. It is useful in conditions where resistance factors are compromised such as dysvascular conditions and disorders involving immunosuppression.
Clinically Accepted Indications for HBO (USA)
Osteoradionecrosis and soft tissue necrosis
Acute Thermal burns
Carbon monoxide poisoning
Acute Gas Embolism
Acute Gas Gangrene
Chronic Refractory Osteomyelitis
Soft Tissue Infection
Aerobic and Anaerobic
Crush Injury with Acute Traumatic Ischemia
Compromised Skin Flaps and Grafts
Enhancement of Healing in Selected Problem Wounds - Diabetic Foot Ulcers
Selected Refractory Mycoses
Acute Blood Loss AnemiaAreas of Active Experimental Interest
Delayed Radiation Injury
Idiopathic Sudden Sensorieneural Hearing Loss
Areas of Active Experimental Interest
Stroke and Traumatic Brain Injury
Renal Artery Insufficiency - Acute, Central
Reattachment and Suturing of Severed Limbs