WASHINGTON, D.C. -- Hyperbaric oxygen therapy offers enough promise for treating victims of stroke and other debilitating traumas and diseases of the central nervous system to warrant in-depth scientific studies, a medical researcher said today.
Speaking at a meeting of the Space and Underwater Research Group of the World Federation of Neurology, Dr. Stephen Thom said that doctors do not have a clear understanding of why hyperbaric oxygen therapy works. Nonetheless, small-scale studies indicate that it may be useful, he said.
The meeting is being coordinated by the Stroke Research Center of the Wake Forest University Baptist Medical Center.
Hyperbaric oxygen therapy, or HBOT, refers to the practice of putting patients in pressure chambers and having them breathe pure oxygen at two or more times normal atmospheric pressure. HBOT significantly increases the amount of oxygen in the blood, and it is accepted treatment for carbon monoxide poisoning, decompression sickness, air embolism and certain other conditions.
But research to be presented at the meeting this week suggests that hyperbaric oxygen therapy could save millions or even billions of dollars annually in treating victims of stroke, epilepsy and spinal cord injury.
Particularly with respect to treating stroke, "There is potential for a meaningful benefit for patients," said Thom, president of the Undersea and Hyperbaric Medical Society.
The problem is, there's no reason why hyperbaric oxygen therapy should work. "There's a lot of data to say that if a blood vesssel is occluded (blocked), simply providing more oxygen to the blood is not going to help," Thom said. "There's no blood getting through so simply getting more oxygen in the blood is not getting more oxygen to the tissue.
"In fact, there are some theoretical arguements to suggest that giving more oxygen may be harmful," he said.
Nonetheless, he said, "There is clinical and animal data to suggest that it might help, but the studies are not conclusive. So it's fertile ground for research. There's reason to think that it might help but it's yet to be proven. It needs more research."
Thom has been studying HBOT to understand why it seems to work. One possibility, he said, is that it may affect the immune system. When a blood vessel is blocked, and reopened, surrounding tissue is often subjected to what are called "reperfusion injuries." Some studies suggest that these injuries may occur because of abnormal immune system response to the return of blood flow.
These injuries seem to benefit from hyperbaric oxygen therapy, suggesting that the higher level of oxygen in the blood prevents this abnornal immune response.
The four-day meeting -- the Congress on Cerebral Ischemia, Vascular Dementia, Epilepsy and CNS Injury: New Aspects of Prevention and Treatment from Space and Underwater Exploration -- continues through Wednesday noon at the Washington Marriott Wardman Park Hotel, formerly the Sheraton Washington.