High-Pressure Chambers Could Prevent Paralysis After SCI
May 14, 1998
Source: ScienceDaily Magazine
WASHINGTON D.C. -- High-pressure chambers used to treat deep sea
divers for decompression sickness could play a key role in preventing permanent spinal
cord damage and paralysis to many of the thousands of Americans who suffer spinal cord
injuries every year, a doctor from Scotland reported May 10.
Dr. Philip James of the University of Dundee reported at a conference here that putting
patients under high pressure forces more cell-resuscitating oxygen into damaged spinal
nerves than is possible at normal atmospheric pressure.
"It may mean the difference between significant disability and no
disability," James said.
James made his remarks at a meeting of the Space and Underwater Research Group of the
World Federation of Neurology. The meeting is being coordinated by the Stroke Research
Center of the Wake Forest University Baptist Medical Center.
James has been a consulting physician to North Sea diving operations for 25 years.
Divers sometimes suffer from bubbles in their spinal cord, resulting in tissue damage that
is similar to the bruising that spinal cords suffer from traumatic injury.
Typically, nerve tissue in the spinal cord is starved of oxygen because the small
capillaries that carry blood to the tissue are damaged. If adequate blood flow is not
restored within hours, the nerve cells in the spinal cord die from lack of oxygen. This
can result in complete or partial paralysis.
Placing these divers in hyperbaric chambers and raising the pressure to 2.8 times the
normal atmospheric pressure hastens their recovery, James said, because under high
pressure the blood carries proportionally more oxygen. This raises the oxygen levels in
the damaged nerve tissue toward normal levels to assist recovery. For spinal cord injury
patients, raising the pressure to two times atmospheric pressure would be adequate, James
said.
An estimated 250,000 Americans have spinal cord injuries, according to the American
Paralysis Association. On average, 11,000 new injuries are reported every year. The cost
of treating and caring for these individuals can range from $600,000 to $1.3 million over
a lifetime, depending on age and the degree of injury.
James cautioned that hyperbaric oxygen therapy, as the high-pressure procedure is
called, is useful only in cases where the spinal cord is bruised, but not in cases where
it is physically severed.
The National Spinal Cord Injury Statistical Center does not keep statistics on what
proportion of spinal cord injuries are limited to bruising, but James said "the vast
majority" fall into this category.
A number of very positive animal studies on the use of hyperbaric oxygen therapy in
treating spinal cord injury have been published, James said. On humans, it has been used
on a number of spinal cord injured patients over the past 20 years in the United States,
Germany and Australia but no large scale studies have been conducted.
One impediment was that until recently, there was no way to tell whether the spinal
cord was bruised or severed, James said.
"If you go on the physical symptoms of the patient you can't tell," he said.
Recent improvements in magnetic resonance imaging (MRI), however, now make it possible
to determine which spinal cord casualties should be treated with hyperbaric oxygen
therapy.
Unfortunately, James said, "most trauma centers do not have hyperbaric chambers,
which is a tragedy, and most physicians don't understand the need to increase the
dissolved oxygen in the plasma of the blood. They stop at hemoglobin saturation."
Note: This story has been adapted from a news release issued by
Wake Forest University Baptist Medical
Center (formerly Bowman Gray/Baptist Hospital Medical Center) for journalists and other members of the public. If you wish to quote from any
part of this story, please credit Wake Forest University Baptist Medical Center as the
original source.
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