Hyperbaric oxygen therapy, or HBOT, is a type of treatment used to speed up healing of carbon monoxide poisoning, gangrene, stubborn wounds, and infections in which tissues are starved for oxygen.
If you undergo this therapy, you will enter a special chamber to breathe in pure oxygen in air pressure levels 1.5 to 3 times higher than average. The goal is to infuse the blood with enough oxygen to repair tissues and restore normal body function.
Hyperbaric oxygen therapy was first used in the U.S. in the early 20th century, when Orville Cunningham used pure oxygen to successfully treat someone dying from the flu. He developed a hyperbaric chamber but dismantled it after his use of the therapy for other conditions failed.
The therapy was resurrected in the 1940s, when the U.S. Navy used hyperbaric oxygen to treat deep-sea divers who had decompression sickness. By the 1960s, the therapy was also used to combat carbon monoxide poisoning.
Today, it's still used to treat sick scuba divers and people suffering from carbon monoxide poisoning, including firefighters and miners, but it also has been approved for more than a dozen ailments ranging from burns to bone disease:
Carbon monoxide poisoning
Gas gangrene (a form of gangrene in which gas collects in tissues)
Inadequate blood flow in the arteries, including those supplying problem wounds or the retina during central retinal arterial occlusion (this is a blockage of a blood vessel in one eye that can cause sudden vision loss)
Compromised skin grafts and flaps
Infection in a bone (osteomyelitis)
Delayed radiation injury
Flesh-eating disease (also called necrotizing soft tissue infection)
Air or gas bubble trapped in a blood vessel (air or gas embolism)
Conditions that cause insufficient oxygen levels to reach the body's tissues
Skin infections that are causing the tissues to die
Medicare and many insurance companies cover hyperbaric oxygen therapy for these conditions, although Medicare does not cover HBOT for the treatment of burns.
Conditions for which HBOT is not approved include the treatment of cancer, AIDS, cerebral palsy, autism, chronic fatigue syndrome, and any other diseases not on the above list.
HBOT helps wound healing by bringing oxygen-rich plasma to tissue starved for oxygen. Wound injuries damage the body's blood vessels, which release fluid that leaks into the tissues and causes swelling. This swelling deprives the damaged cells of oxygen, and tissue starts to die. HBOT reduces swelling while flooding the tissues with oxygen—the elevated pressure in the chamber can produce a 10- to 15-fold increase in the amount of oxygen in the blood. HBOT aims to break the cycle of swelling, oxygen starvation, and tissue death.
HBOT prevents "reperfusion injury." That's the severe tissue damage that occurs when the blood supply returns to the tissues after they have been deprived of oxygen. When blood flow is interrupted by a crush injury, for instance, a cascade of events inside the damaged cells leads to the release of harmful oxygen radicals. These molecules can do irreversible damage to tissues and cause the blood vessels to clamp up and stop blood flow. HBOT encourages the body's oxygen radical scavengers to seek out the problem molecules and thus allow healing to proceed.
HBOT helps block the action of harmful bacteria and strengthens the body's immune system. HBOT can inactivate the toxins of certain bacteria. It also increases oxygen concentration in the tissues, which helps them resist infection. In addition, the therapy improves the ability of white blood cells to find and destroy invaders.
HBOT encourages the formation of new collagen (connective tissue) and new skin cells. It does so by encouraging new blood vessel formation. It also stimulates cells to produce certain substances, like vascular endothelial growth factor, which attract and stimulate endothelial cells necessary for healing.
Hyperbaric oxygen therapy uses two types of chambers:
Monoplace chamber. This is a chamber built for one person. It's a seven-foot-long clear plastic tube that resembles an MRI machine. The patient slips into the device, which is slowly pressurized with 100 percent oxygen.
Multiplace chamber. This chamber, or room, can fit two or more people people at once. The treatment is largely the same, except that people breathe pure oxygen through masks or hoods.
Only a doctor or health provider should prescribe hyperbaric oxygen therapy. A number of hospitals offer hyperbaric oxygen chambers, where people relax, sit, or lie comfortably and take deep breaths in sessions that last up to two hours.
Your ears may feel plugged as the pressure is raised, just as when you're in an airplane or the mountains. Simple swallowing or chewing gum will "pop" the ears back to normal hearing levels.
Your blood carries the extra oxygen throughout the body, infusing the injured tissues that need more oxygen so they can begin healing. When a session is complete, you may feel lightheaded. Mild side effects include claustrophobia, fatigue, and headaches.
Several sessions may be needed, so check beforehand to see whether your insurance company or Medicare covers the cost.
Hyperbaric oxygen therapy is not for everyone. It should not be used by people who have a pacemaker, a cold or fever, heart failure, or certain types of lung disease. It is also not recommended for people taking chemotherapy drugs or for pregnant women unless they are in grave danger and have no other options.
The most common complication after HBOT is trauma to the middle ear. Other possible complications are eye damage and sinus problems. In rare, severe cases, a person can get oxygen toxicity, which can lead to seizures, fluid in the lungs, lung failure or other problems. Considering the potential risks and benefits, the decision to use hyperbaric oxygen therapy must be carefully made after a detailed discussion with your doctor..
The best way to protect yourself against possible hazards of hyperbaric oxygen therapy is to be treated in a hospital setting with trained medical personnel. The doctor directing your therapy should have a minimum of 40 hours' training from the Undersea and Hyperbaric Medical Society—ask to see his or her certificate of completion for the course.
HBOT use in other places besides hospitals is largely unregulated. Although you can find reputable clinics, some practitioners take advantage of patients desperate for a cure for themselves or their children. Remember, no scientific evidence says that HBOT benefits people with cancer, AIDS, cerebral palsy, or autism, among other conditions, so beware of anyone making these claims.
In addition, some chiropractors and clinics use portable fabric HBOT chambers, the routine use of which, experts say, poses a serious fire and explosion hazard. Fires or explosions associated with the use of hyperbaric chambers have been linked to approximately 80 deaths worldwide. Today, hyperbaric oxygen chambers in the hospital setting by appropriately trained medical personnel have good safety records.