Osteomyelitis is an infection of the bone. Refractory osteomyelitis is a bone infection which has not responded to appropriate treatment. Hyperbaric oxygen increases the oxygen concentration in infected tissues, including bone. Hyperbaric oxygen directly kills or inhibits the growth of organisms which prefer low oxygen concentrations (strict anaerobes). These effects occur through the oxygen-induced production of toxic radicals or through an indirect effect medicated through the white blood cells (polymorphonuclear leukocytes). Conversely, hyperbaric oxygen has no direct effect on organisms which prefer high oxygen concentrations (aerobes). In fact, hyperoxic conditions may induce aerobic organisms to produce increased concentrations enzymes protective against oxygen radicals (e.g. superoxide dismutase). When hyperbaric oxygen increases the oxygen tension in infected tissue, however, the oxygen-dependent killing mechanisms of the polymorphonuclear leukocyte are provided sufficient oxygen to function. Thus, hyperbaric oxygen treatment provides the necessary substrate (oxygen) for the killing of aerobic organisms by the polymorphonuclear leukocyte.
Hyperbaric oxygen also augments the efficacy of bacterial killing by certain antibiotics (aminoglycosides, vancomycin, quinolones and certain sulfonamides). Hyperbaric oxygen provides adequate oxygen for fibroblast activity, cells which promote healing in hypoxic tissues. Finally hyperbaric oxygen prevents polymorphonuclear leukocytes from adhering to damaged blood vessel linings. This decreases the degree of inflammation which may accompany the surgical treatment of refractory osteomyelitis. Hyperbaric oxygen is used clinically for the treatment of refractory osteomyelitis as noted above. Hyperbaric oxygen is adjunctive therapy and is used with appropriate antibiotics, surgery and nutrition. There are open, patients used as there own controls and randomized clinical studies supporting the use of HBO for the treatment of refractory osteomyelitis.
Cancer treatment has improved significantly over the past decade. Although cure of the cancer is still the highest priority of treatment, cancer specialists have come to recognize the ever-increasing importance of quality of life to the cancer survivor. One-half of the estimated 1.2 million new cases of invasive cancer will receive radiation therapy as a part of their cancer treatment. Side effects of this therapy can be very toxic, especially when combined with chemotherapy. Some people are more sensitive to radiation damage than others, and there are no reliable tests available as yet to identify those patients who will experience the worst side effects. Radiation doses must be adequate to control the cancer; otherwise, there is no purpose in treating the patient.
Most radiation cancer specialists or oncologists design their treatment protocols to give the best dose to control the tumor and still have no more than 5% of patients develop severe reactions to treatment. Radiation side effects are generally divided into two categories. First, there are those that happen during or just after the treatment, called acute reactions. Second, there are those that happen months or even years after the treatment, called chronic complications. The acute side effects almost always resolve with time and are treated in such a way as to address the patient’s symptoms. For example, when a patient has a cancer of the mouth or throat, it becomes very difficult for the patient to eat during and just after treatment because the lining of the mouth and throat becomes raw and painful. The cells which make up the linings of the gastrointestinal tract are sensitive to radiation. Both cancer cells and the cells that line the gastrointestinal tract have a high rate of growth, and this rapid growth rate makes them more sensitive to radiation damage. Fortunately, the normal tissue cells have excellent repair abilities and within a few weeks after the completion of radiation, this damage is repaired. In the meantime, the patient is supported with pain medicine and supplemental nutrition. Unfortunately, chronic complications often may not get better with time and are likely to get worse.
Almost all chronic radiation complications result from scarring and narrowing of the blood vessels within the area which has received the treatment. If this process progresses to the point that the normal tissues are no longer receiving adequate blood supply, death or necrosis of these tissues can occur. In the past, a severe level of necrosis would require surgical removal of the damaged tissue. This would be a devastating blow for a patient whose cancer has been cured. For example, though it occurs rarely, a patient who has had cancer of the voice box cured might require the removal of the voice box due to radiation damage. Chronic radiation damage is called “osteoradionecrosis” when the bone is damaged and “soft tissue radionecrosis” if it is muscle, skin or internal organs which have been damaged by the radiation.
Since the 1970’s, surgeons of the head and neck region have come to recognize the value of hyperbaric oxygen treatments in treating damage of the jaw bone due to radiation. Hyperbaric oxygen has had some of its most dramatic successes in treating or preventing damage to the jaw bone as a result of radiation treatments. It has now also been applied to damage of the brain, damage of muscle and other soft tissues of the face and throat, damage to the chest wall, abdomen and pelvis as a result of radiation treatment. Papers in medical journals also report success in treating damage to the bladder and intestines due to radiation. The high dose oxygen provided in the hyperbaric chamber is carried in the patient’s circulation to the site of injury to be available for repair of the damage done by the narrowing and scarring of the blood vessels. Each treatment typically takes one to two hours, and usually 30-40 daily treatments are needed for healing radiation damage. Most insurance companies, including Medicare, will provide coverage to pay for hyperbaric treatments for chronic radiation injuries.
Problem wounds are those which fail to respond to established medical and surgical management. Such wounds usually develop in compromised hosts with multiple local and systemic factors contributing to inhibition of tissue repair. These include diabetic feet, compromised amputation sites, nonhealing traumatic wounds, and vascular insufficiency ulcers (ulcers with poor circulation). All share the common problem of tissue hypoxia (low tissue oxygen level, usually related to impaired circulation). Diabetic foot wounds are one of the major complications of diabetes and an excellent example of the type of complicated wound which can be treated with hyperbaric oxygen. Fifty percent of all lower extremity amputations in the United States are due to diabetes, at a cost of more than one billion dollars per year. It is well known that many diabetics suffer circulatory disorders that create inadequate levels of oxygen to support wound healing. Hyperbaric oxygen therapy is a treatment in which patients receive high concentrations of oxygen under pressure in order to increase the oxygen level in the blood and tissues. The elevation in tissue oxygen which occurs in the hyperbaric chamber induces significant changes in the wound repair process that promote healing.
When hyperbaric treatment is used in conjunction with standard wound care, improved results have been demonstrated in the healing of difficult or limb threatening wounds as compared to routine wound care alone.