Hyperbaric oxygen therapy involves breathing pure oxygen in a pressurized environment. Hyperbaric oxygen therapy is a well-established treatment for decompression sickness, a potential risk of scuba diving. Other conditions treated with hyperbaric oxygen therapy include serious infections, bubbles of air in your blood vessels, and wounds that may not heal as a result of diabetes or radiation injury.

In a hyperbaric oxygen therapy chamber, the air pressure is increased two to three times higher than normal air pressure. Under these conditions, your lungs can gather much more oxygen than would be possible breathing pure oxygen at normal air pressure.

When your blood carries this extra oxygen throughout your body, this helps fight bacteria and stimulate the release of substances called growth factors and stem cells, which promote healing.

Your body's tissues need an adequate supply of oxygen to function. When tissue is injured, it requires even more oxygen to survive. Hyperbaric oxygen therapy increases the amount of oxygen your blood can carry. With repeated scheduled treatments, the temporary extra high oxygen levels encourage normal tissue oxygen levels, even after the therapy is completed.

Hyperbaric oxygen therapy is used to treat several medical conditions. And medical institutions use it in different ways. Your doctor may suggest hyperbaric oxygen therapy if you have one of the following conditions:

• Severe anemia
• Brain abscess
• Bubbles of air in your blood vessels (arterial gas embolism)
• Burns
• Carbon monoxide poisoning
• Crushing injury
• Deafness, sudden
• Decompression sickness
• Gangrene
• Infection of skin or bone that causes tissue death
• Nonhealing wounds, such as a diabetic foot ulcer
• Radiation injury
• Skin graft or skin flap at risk of tissue death
• Traumatic brain injury
• Vision loss, sudden and painless

Hyperbaric oxygen therapy is generally a safe procedure. Complications are rare. But this treatment does carry some risk.

Potential risks include:

• Middle ear injuries, including leaking fluid and eardrum rupture, due to changes in air pressure
• Temporary nearsightedness (myopia) caused by temporary eye lens changes
• Lung collapse caused by air pressure changes (barotrauma)
• Seizures as a result of too much oxygen (oxygen toxicity) in your central nervous system
• Lowered blood sugar in people who have diabetes treated with insulin
• In certain circumstances, fire — due to the oxygen-rich environment of the treatment chamber

You'll be provided with a hospital-approved gown or scrubs to wear in place of regular clothing during the procedure.

For your safety, items such as lighters or battery-powered devices that generate heat are not allowed into the hyperbaric chamber. In addition, you may need to remove hair and skin care products that are petroleum based, as they are a potential fire hazard. Your health care team will provide instruction on preparing you to undergo hyperbaric oxygen therapy.

During hyperbaric oxygen therapy

Hyperbaric oxygen therapy typically is performed as an outpatient procedure but can also be provided while you are hospitalized.

In general, there are two types of hyperbaric oxygen chambers:

• A unit designed for 1 person. In an individual (monoplace) unit, you lie down on a table that slides into a clear plastic chamber.
• A room designed to accommodate several people. In a multiperson hyperbaric oxygen room — which usually looks like a large hospital room — you may sit or lie down. You may receive oxygen through a mask over your face or a lightweight, clear hood placed over your head.

Whether you're in an individual or multiperson environment for hyperbaric oxygen therapy, the benefits are the same.

During therapy, the air pressure in the room is about two to three times the normal air pressure. The increased air pressure will create a temporary feeling of fullness in your ears — similar to what you might feel in an airplane or at a high elevation. You can relieve that feeling by yawning or swallowing.

For most conditions, hyperbaric oxygen therapy lasts approximately two hours. Members of your health care team will monitor you and the therapy unit throughout your treatment.

After hyperbaric oxygen therapy

Your therapy team assesses you including looking in your ears and taking your blood pressure and pulse. If you have diabetes, your blood glucose is checked. Once the team decides you are ready, you can get dressed and leave.

You may feel somewhat tired or hungry following your treatment. This doesn't limit normal activities.

To benefit from hyperbaric oxygen therapy, you'll likely need more than one session. The number of sessions is dependent upon your medical condition. Some conditions, such as carbon monoxide poisoning, might be treated in three visits. Others, such as nonhealing wounds, may require 40 treatments or more.

To effectively treat approved medical conditions, hyperbaric oxygen therapy is usually part of a comprehensive treatment plan provided with other therapies and drugs that are designed to fit your individual needs.