History of Hyperbaric Medicine
The term hyperbaric literally means "high pressure." Hyperbaric chambers are high-pressure chambers used to therapeutically treat a variety of conditions through hyperbaric oxygen therapy, or HBO. Although considered a new and progressive therapy, the concept of hyperbaric oxygen therapy has been around since 1662. According to the London Diving Chamber, HBO evolved with diving medicine and has long been accepted as the primary treatment for divers with decompression sickness (nitrogen bubbles in the blood).
Hyperbaric Oxygen Therapy
HBO therapy entails the use of 100-percent oxygen at elevated pressures for therapeutic purposes. Normally the air we breathe at sea level contains only 21 percent oxygen. This quantity is more than sufficient to sustain our lives, however there are known benefits to breathing higher concentrations of oxygen under greater pressures for individuals with certain disorders or injuries. These physiologic benefits include bubble reduction (for decompression sickness), healing hyperoxygenation of blood and tissue, constriction of blood vessels, enhanced immune function and the creation of new blood vessels.
Increased oxygen supply speeds wound healing, increases white blood cell function and antimicrobial activity to damaged and infected tissues. Individuals who have suffered air embolism, decompression sickness, burns, carbon monoxide poisoning, cerebral edema, crush injuries, stroke, diabetic wounds, trauma, gangrene or infection can benefit from treatment in a hyperbaric chamber (Fundamentals of Respiratory Care).
Administering oxygen at higher pressures causes up to 20 times more oxygen to be absorbed by the blood and transferred to injured organs and tissues (Penn Medicine). This speeds healing and recovery time in addition to other benefits.
Types of Chambers
There are two types of hyperbaric chambers commonly in use--multiplace chambers and monoplace chambers. The multiplace chamber is a larger pressurized cylinder capable of holding up to a dozen patients. Multiplace chambers have airlocks to allow exit and entry of medical personnel and patients without affecting the pressure. Medical staff directly care for patients within the tank, and patients are required to wear oxygen masks.
The typical monoplace chamber consists of a Plexiglas cylinder that is transparent and large enough for only one patient. The oxygen in the entire cylinder is kept at 100-percent during treatments, so therefore it is unnecessary for the patient to wear a mask.
Complications of HBO
Although hyperbaric oxygen therapy has multiple benefits, it also comes with some risks. Common complications include pressure-associated trauma to enclosed body cavities such as the inner ear or sinuses and eardrum rupture. In rare instances, HBO therapy can also cause pneumothorax (trapped air inside the pleural cavity) and air embolism (air in the blood vessels that can cause blockage), but usually not in people with normal lung function. Oxygen can also be toxic at high concentrations, but this rarely occurs with the treatment times and pressures used for clinical HBO therapy.
References
- Hospital based London Diving Center
- Fundamentals of Respiratory Care; Robert L. Wilkins, PhD. et al.; 2009
- Hyperbaric Medicine
