Last updated on 07 April 08

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Hyperbaric medicine, also known as hyperbaric oxygen therapy (HBOT) is the medical use of oxygen at a higher than atmospheric pressure. Hyperbaric is the only technique available to overcome the natural limit of oxygen solubility in blood. The hyperbaric procedure is done in specially designed chambers that permit the delivery of 100% oxygen at ambient pressures that are greater than atmospheric. This allows dissolved oxygen in the blood and clear fluids to be increased by up to 20 times normal levels. This additional oxygen in solution is almost sufficient to meet tissue needs without contribution from oxygen bound to hemoglobin and is responsible for most of the beneficial effects of this therapy. When body tissues are severely traumatized such as in accidents and falls, the rate of complications such as infections, non-healing fractures and amputation can range up to 50%. Crush injury involves severe trauma to bone, soft tissue, nerve, and vascular structures. Acute traumatic ischemia occurs when there is a severe injury to a limb and the circulation of the extremity becomes compromised. This ischemic compromise may be severe enough to place the entire extremity at risk of necrosis and amputation. The immediate threat to the limb is whether perfusion is sufficient to maintain viability of the tissues. Posttraumatic edema, which is associated with traumatic injuries, and ischemia further reduce oxygen availability to tissues. When tissue oxygen tensions fall below 30 mmHg, the host responses to infection and ischemia are compromised. Specifically, white blood cell killing becomes defective or nonexistent and host repair processes such as fibroblast secretion of collagen are arrested. Without a collagen matrix in the wound, neovascularization and wound healing cannot occur. The primary rationale for using HBO2 is that it increases tissue oxygen tensions to levels, which make it possible for the host responses to become functional. Sufficient oxygen becomes physically dissolved in the plasma to keep tissues alive despite inadequate hemoglobin-borne oxygen. Edema reduction secondary to vasoconstriction is another effect of Hyperoxygenation. Thus, the immediate effects of HBO2 are threefold in acute traumatic ischemia: a) enhanced oxygenation at the tissue level, b) increased oxygen delivery per unit of blood flow, and c) edema reduction. As an adjunct to orthopedic surgery and antibiotics, HBO therapy can significantly decrease costs and complications as well as duration for recovery.