What is hyperbaric oxygen therapy (HBOT)?
Hyperbaric oxygen therapy (HBOT) is breathing 100% oxygen while under increased atmospheric pressure. During this therapy, a person breathes pure oxygen in a pressurized chamber or room.
The use of HBOT as a treatment procedure started in the 1600s. The first well-known chamber for HBOT was built and run by a British clergyman named Henshaw.
Hyperbaric oxygen therapy is commonly used under conditions of low oxygen in the tissues (tissue hypoxia) as in some wounds or to treat decompression sickness (a hazard of scuba diving) or gas embolism in which gas bubbles hamper blood flow.
Hyperbaric oxygen therapy may be given in a multiplace chamber that treats many patients at the same time, generally with a nurse or another inside observer who monitors the patients and assists with equipment manipulation or emergencies. This allows for closer monitoring of critically ill patients.
Single occupancy chambers or monoplace chambers serve one person at a time. They are most appropriate for the treatment of stable patients with long-term medical conditions.
What is hyperbaric oxygen therapy used to treat?
Hyperbaric oxygen therapy is used to treat several medical conditions including:
- Decompression sickness and air embolism: Decompression sickness (DCS) refers to symptoms that occur when divers breathing compressed air return to the surface too rapidly or when the aviators fly over 5500 m, leading to the formation of air bubbles in the blood circulation. These bubbles act like clots (emboli) and block the blood supply and damage the organs, first due to direct mechanical effects and later due to biochemical actions from the inert (non-reactive) gas dissolved in the blood or tissues. People with a physical defect or hole in the heart, such as patent foramen ovale, are at an increased risk.
- Carbon monoxide poisoning: It occurs when a person inhales the colorless and odorless carbon monoxide gas. It is a leading cause of death from poisoning despite improved awareness. Carboxyhemoglobin (a product formed when carbon monoxide combines with the oxygen-carrying substance, hemoglobin, in the blood) reduces oxygen release to tissues. Hyperbaric oxygen therapy reduces the life of carboxyhemoglobin by replacing carbon monoxide with oxygen in the hemoglobin.
- Enhanced wound healing: Certain long-term non-healing wounds such as diabetic wounds, venous stasis ulcers, arterial ulcers, or pressure ulcers (bed sores) may be treated with hyperbaric oxygen therapy.
- Non-healing skin grafts and flaps
- Crush injury and compartment syndrome (a painful condition that occurs when excessive pressure is built up within and between the muscles)
- Soft-tissue infections (such as gas gangrene, necrotizing fasciitis, and Fournier’s gangrene)
- Delayed radiation injury (radiation injury that may appear anywhere from six months to years after radiotherapy)
- Refractory osteomyelitis (non-healing bone infections)
- Severe anemia
- Central retinal artery occlusion (CRAO): It is a sudden, painless loss of vision caused by the obstruction of the central retinal artery (a particular blood vessel in the eye) that can cause permanent vision loss.
- Idiopathic sudden sensorineural hearing loss (a type of hearing loss with unknown reasons)
What are the side effects of hyperbaric oxygen therapy?
Hyperbaric oxygen therapy is generally safe and well-tolerated. Side effects may include: