What is Hyperbaric Oxygen Therapy (HBOT)?
Hyperbaric Oxygen Therapy (HBOT) is a medical treatment that involves delivering oxygen at increased atmospheric pressure to heal injuries to the body. According to Dr. Paul G. Harch, a pioneer and leading authority on hyperbaric oxygen therapy and research, “Oxygen under pressure works as a drug to treat basic disease processes that are common to many acute and chronic conditions. By treating the disease processes the diseases are treated also.”
How Does Hyperbaric Oxygen Therapy (HBOT) Work?
Hyperbaric Oxygen Therapy (HBOT) works by fully enclosing a person in a chamber, increasing the pressure in the chamber, and then delivering pure oxygen. The entire body and all organs and tissues in the body are exposed to increased oxygen pressure. The oxygen is breathed into our lungs where it dissolves in the blood and is distributed throughout the body.
Saturating the Body with Oxygen
At sea level, or 1 atmosphere of pressure, the air we breathe is only 21% oxygen. This small amount of oxygen is enough to saturate 98% of the oxygen carrying protein in our blood, the hemoglobin. With hyperbaric oxygen, the body is exposed to 1-3 atmospheres of pure oxygen or 100%-300% oxygen, nearly 15 times the amount of oxygen in our air. As the pressure is increased in the chamber, the last 2% of hemoglobin is quickly saturated with oxygen. As the pressure is further increased, all of the remaining oxygen is dissolved in the liquid portion of the blood. With greater pressure more oxygen is dissolved. This liquid portion can then deliver very high amounts of oxygen to all of the tissues in the body, enough oxygen to keep a patient alive without the hemoglobin.
This was demonstrated in a famous 1960 experiment in the Netherlands called “Life Without Blood.” In this experiment a pig was put in a hyperbaric chamber and pressurized to 3 atmospheres, or 300% oxygen, while all of the pig’s blood was exchanged with saline (salt water). The amount of oxygen dissolved in the saline by Hyperbaric Oxygen Therapy (HBOT) was enough to keep the pig alive in the chamber without blood. At the end of the experiment, they replaced the blood and brought the pig out of the chamber alive.
Hyperbaric Oxygen Therapy (HBOT) is particularly effective in delivering increased amounts of oxygen to wounds in the body that have poor blood supply or injured tissue that is swollen. By exposing a person daily to increased amounts of oxygen for 1-2 hours, the body is able to speed up the healing process at any sites of injury, including bone, soft tissue, the brain, spinal cord, heart, liver, etc.
Types of HBOT Chambers
Hyperbaric Oxygen Therapy (HBOT) can be administered in single person chambers called monoplace chambers, or large chambers that can accommodate multiple patients called multiplace chambers. There are even hyperbaric rooms of various sizes equipped with furniture and other comforts. In the monoplace chambers, patients usually are compressed with pure oxygen and breathe pure oxygen. In the multiplace chambers or rooms, the vessels are compressed with air for economic reasons and then the patient breathes 100% oxygen through a hood or mask at the desired pressure. Regardless of the size, shape, or configuration, the treatment effect is the same for the patient as long as the chamber can be compressed and oxygen delivered at the desired pressure.
What is Hyperbaric Oxygen Therapy (HBOT) used for?
Hyperbaric Oxygen Therapy (HBOT) applications can be broadly divided into two categories, emergency conditions (acute) and chronic conditions. The emergency applications take advantage of Hyperbaric Oxygen Therapy’s (HBOT’s) ability to stop inflammation, infection, and tissue destruction and oxygenate tissues that are starved for oxygen.
These acute conditions include decompression sickness (“the bends”), air embolism (air in the arteries of the body due to a rupture of the lungs in diving or accidental injection of air during medical procedures), carbon monoxide poisoning, burns, the flesh-eating bacteria, gas gangrene (occurs in trauma and war wounds), surgical flaps and grafts that are failing due to low oxygen and blood supply, massive loss of blood where transfusion is not possible (e.g., Jehovah’s Witnesses), brain abscesses, crush injury, sudden loss of vision due to a blood clot in the main artery to the eye, and acute loss of blood supply to an arm or leg due to blood vessel disease or trauma (accidental amputation). In all of these conditions, Hyperbaric Oxygen Therapy (HBOT) should be applied as soon as possible after the injury or insult or at the start of the infection. When delivered emergently, Hyperbaric Oxygen Therapy (HBOT) can be life and limb saving.
The other category of applications is chronic or stable conditions. In these conditions, Hyperbaric Oxygen Therapy (HBOT) stimulates the growth of new tissue in damaged areas of the body. It does this by causing release of growth and repair hormones. These conditions include radiation wounds, chronic bone infections, and non-healing wounds of any type such as diabetic foot wounds, venous stasis wounds of the legs, or wounds due to inflammation of the blood vessels such as in rheumatoid arthritis and autoimmune conditions. In most of these disorders, Hyperbaric Oxygen Therapy (HBOT) heals by causing the growth of tiny new blood vessels.
Other Conditions that are Amenable to Hyperbaric Oxygen Therapy (HBOT)
The above conditions constitute those disorders that are typically reimbursed by Medicare, Medicaid, insurance companies, and HMO’s. However, as mentioned earlier, Hyperbaric Oxygen Therapy (HBOT) treats basic disease processes and the diseases that the processes cause, irrespective of who is paying for the treatment. Since Hyperbaric Oxygen Therapy (HBOT) improves low oxygen levels and inhibits inflammation, infection, and tissue destruction, the potential application of Hyperbaric Oxygen Therapy (HBOT) to any disease characterized by low oxygen, inflammation, infection, and tissue destruction is huge. In fact, there is evidence for the application of Hyperbaric Oxygen Therapy (HBOT) to a much larger list of indications than is currently applied in the United States. For example, in Japan, Russia, and China, Hyperbaric Oxygen Therapy (HBOT) is used for stroke, coma, brain injury after cardiac arrest, fetal problems during the last 3 months of pregnancy, heart disease, dementia, detoxification, traumatic brain injury, and other diseases. Interestingly, there are more high quality studies of Hyperbaric Oxygen Therapy (HBOT) in acute severe traumatic brain injury than for nearly any indication for Hyperbaric Oxygen Therapy (HBOT) in the United States. The majority of these studies show that just a few Hyperbaric Oxygen Treatments (HBOTs) within the first few days after injury can reduce the death rate by as much as 60%.
A more detailed discussion of all of these subjects is provided in The Oxygen Revolution, the lay medical book on Hyperbaric Oxygen Therapy (HBOT) by Dr. Paul G. Harch and co-author Virginia McCullough. In the book, Dr. Harch describes the multiple present and future applications of Hyperbaric Oxygen Therapy (HBOT) as well as the revolutionary effect Hyperbaric Oxygen Therapy (HBOT) is going to have on the medical field.
Where to Obtain Hyperbaric Oxygen Therapy (HBOT)
Hyperbaric Oxygen Therapy (HBOT) can be obtained in a hospital or a freestanding clinic.
Hyperbaric Oxygen Therapy (HBOT) has been traditionally delivered in hospital-based departments or wound care departments on hospital campuses. Many of these facilities treat both the emergency as well as the chronic conditions.
In the past 15 years however, Hyperbaric Oxygen Therapy (HBOT) treatment has become more efficient and convenient through the establishment of freestanding clinics. These clinics usually are not equipped to treat the emergency conditions and so have focused only on the chronic conditions. Increasingly, these freestanding clinics also treat “off-label” conditions such as chronic neurological conditions. Examples include cerebral palsy, autism, chronic traumatic brain injury, and chronic stroke. It is estimated that there are now 800 Hyperbaric Oxygen Therapy (HBOT) centers in the United States.
Regardless of whether the Hyperbaric Oxygen Therapy (HBOT) center is hospital-based or freestanding, the most important attribute of any facility is whether there is a doctor in attendance. Because Hyperbaric Oxygen Therapy (HBOT) is both a medical procedure and drug, there are risks and side effects that should be evaluated by a physician before proceeding with treatment. Similarly, a physician should be present during treatment for continuous observation and assessment.
The Cost of Hyperbaric Oxygen Therapy (HBOT)
The cost of Hyperbaric Oxygen Therapy (HBOT) is determined largely by where a patient receives Hyperbaric Oxygen Therapy (HBOT), what type of medical coverage (reimbursement) is present, and what condition is treated. In the hospital-based centers, only the typically reimbursed indications are treated and the charge is $1,000-2,000/hour.
In a freestanding center, treatment of the same conditions costs far less and can be as low as $200/hour. If the Hyperbaric Oxygen Therapy (HBOT) is reimbursed by either Medicare or Medicaid the charge is nearly the same in a hospital or freestanding center, approximately $250/hour.
For off-label conditions, the freestanding centers are usually the only option for treatment. The average charge at these facilities is about $200/hr or treatment.
Safety and Side-Effects of HBOT
Hyperbaric Oxygen Therapy (HBOT), when done properly, is one of the safest of all medical procedures. The most common side effect is barotrauma, or pressure-caused trauma. Barotrauma occur to closed-air spaces in the body, such as the middle ear space (behind the ear drum) or sinuses during a common cold.
Barotrauma of the Middle Ear
The most frequent complication in Hyperbaric Oxygen Therapy (HBOT) is when a patient can’t equalize the pressure in the middle ear as the chamber pressure is increased. This is similar to the effect on the ears when a commercial airline descends from altitude and the cabin pressure is increased to sea level pressure. Simple swallowing and palate elevating maneuvers are all that are necessary to remedy this problem.
For patients who are unable to equalize the pressure in their ears (behind the eardrum) during Hyperbaric Oxygen Therapy (HBOT), a simple office procedure called myringotomy can be performed. This procedure is the same procedure done for infants who have repeated ear infections. A small plastic hourglass shaped tube is inserted in the eardrum. The tube has a small hole in the middle that allows air to pass freely in and out of the middle ear space during Hyperbaric Oxygen Therapy (HBOT), thus preventing the possibility of barotrauma.
Temporary near-sightedness is another frequent complication of Hyperbaric Oxygen Therapy (HBOT) that occurs in a dose-dependent manner. This means that as the treatment pressure of Hyperbaric Oxygen Therapy (HBOT) is increased, the frequency of this near-sightedness increases (near-sightedness is when close objects are seen more clearly than distant objects). Increased levels of oxygen cause metabolic changes in the eyes that cause distant vision to become blurry. This is very common in patients that undergo Hyperbaric Oxygen Therapy (HBOT) at the higher pressures for the typically reimbursed chronic indications. By the end of the course of 30-40 treatments in these patients, the majority will have some degree of near-sightedness. Most of this nearsightedness resolves within a couple of months after the Hyperbaric Oxygen Therapy (HBOT) ends, although some near-sightedness can remain. This “hyperoxic myopia” is rarely seen at the lower pressures used in off-label neurological conditions.
More serious risks and side effects of hyperbaric oxygen therapy such as air embolism to the brain from barotraumas to the lungs, or fire are extremely rare and easily prevented by proper screening of patients before treatment and proper technique during treatment. With physician evaluation and attendance these risks are minimized during treatment.