Each year approximately 700,000 people suffer a stroke in the United States alone. It is the leading cause of long-term disability in adults, costing an estimated $43 billion per year. For years Western medicine viewed hyperbaric oxygen therapy only as a treatment for decompression sickness. However, doctors now realize that HBOT is beneficial in the treatment of other illnesses, including stroke.
Stroke
A stroke occurs when there is a sudden loss of blood and oxygen to a particular area of the brain. It can be caused by bleeding in the brain or blockage of an artery by a blood clot or buildup of plaques on the arterial walls. Brain cell function requires constant delivery of oxygen from the bloodstream. A lack of oxygen results in cell death. Once the cells die, the parts of the body they control cease working. Cell death following stroke can occur in just minutes. Surrounding the locus of irreparably damaged cells is an area of traumatized tissue wherein the cells are not dead, but are not functioning due to localized swelling.
Hyperbaric Oxygen Therapy
HBOT involves the inhalation of pure oxygen inside a chamber pressurized to greater than one atmosphere. This pressure is more than three times greater than normal air pressure. Under these conditions, the lungs absorb several times more oxygen than they could a normal air pressure. The increased oxygen dissolves into the blood stream and is delivered throughout the body.
Benefits
The elevated blood oxygen levels attained via HBOT promote the growth of new blood vessels, decrease swelling and inflammation, deactivate toxins, increase the body’s ability to fight infections, and improve the rate of healing. When used on stroke patients, HBOT reduces swelling surrounding the site of damage and aids in the formation of new blood vessels. This allows fresh oxygen to reach damaged tissues, helping to restore them. Although the dead cells cannot be resuscitated, the nonfunctioning cells can be reactivated, which in some cases results in substantial recovery of function. By contrast with some stroke treatments, HBOT can provide benefits to stroke patients even when administered years later.
Potential Side Effects
HBOT is considered safe, cost-effective and compatible with other therapies. The risk of side effects is small and generally they are temporary. The most common side effect is pain or pressure in the ears or sinuses. These symptoms usually disappear shortly after the therapy session is over and may be alleviated with over-the-counter pain remedies or sinus medications. Visual changes, such as blurring or myopia, have also been noted. This effect generally dissipates slowly, with normal sight restored within six weeks. Patients with cataracts should talk with their doctors prior to HBOT, as occasionally a maturing or ripping of the cataract may occur. Although the high oxygen concentrations used in HBOT are therapeutically beneficial, extremely high oxygen levels can be toxic. Oxygen toxicity only occurs when the patient is exposed to too high concentrations for long time periods and technicians can prevent it by following the recommended medical protocols precisely. In extremely rare instances, the rapid change in air pressure can rupture the lungs, releasing air into the arteries or chest cavity. Since HBOT involves only slow pressure changes, this is generally not a concern when receiving treatment at a reputable facility.
References
- U.S. Department of Health and Human Services, Agency for Healthcare Research and Quality: Hyperbaric Oxygen Therapy for Brain Injury, Cerebral Palsy, and Stroke; Evidence Report/Technology Assessment: Number 85; September 2003
- Center for New Medicine: Hyperbaric Oxygen Therapy
- MayoClinic.com; Stroke; July 2010
