Hyperbaric medicine is the practice of giving oxygen intermittingly within a pressurized chamber. Since the 17th century, hyperbaric medicine has undergone many changes as scientists figured how it worked and who it would most benefit. Although it is being used as part of the treatment for many diseases such as stroke, cerebral palsy and autism, there is not conclusive evidence of its effectiveness in those illnesses. Currently, the modern indications for hyperbaric oxygen therapy include decompression sickness (the “bends”), carbon monoxide poisoning and acute severe blood loss. Wounds that may also benefit from hyperbaric oxygen include gas gangrene, radiation injury due to cancer treatment and hard to heal wounds like diabetic foot ulcers.
The way hyperbaric oxygen works is by delivering the oxygen through inhalation to the area of concern at the cellular level. When a diver has the bends, he or she has retained too much carbon dioxide (CO2) gas and the extra oxygen helps to drive it out of the tissues. In the case of wound healing, the rate normal wounds heal is oxygen dependent. Factors that delay wounds to heal include recurrent trauma, infection and decreased blood flow. It is not enough to have only the wound surrounded by oxygen. Because the oxygen is inhaled, it is important for the heart and lungs to work so that the oxygen can be delivered effectively. As a result, the orderly sequence of steps is needed for normal healing to occur.
Most people tolerate the treatment well and just need to be able to stay within an enclosed chamber and be able to clear their ears. Absolute contraindications to hyperbaric oxygen therapy include untreated pneumothorax (collapsed lung), current radiation treatment for cancer and past exposure to Adriamycin (chemotherapy for breast cancer).
The following may increase risk for side effects:
- Congestive heart failure or any heart disease
- Emphysema or any lung problems
- Seizures (convulsions)
- Eye problems like optic neuritis or retinal detachment
- Ear implants
- Upper respiratory illness (a cold)
- Fever over 100F
Side effects that may occur due to oxygen toxicity include:
- Nausea, vomiting
- Heart rate changes
- Feeling pale and sweaty
- Anxiety and depression
- Ringing in the ears
Treatment protocols depend on the reason for the use of hyperbaric oxygen therapy. There is solid evidence in the treatment of carbon monoxide poisoning, the bends and gas gangrene. In regards to other specific disease process, the protocols used to treat are based on avoidance of oxygen toxicity. Thus, more data is needed to fully integrate hyperbaric oxygen as part of standard therapy for its broad range of uses.