Hypothermia Studied as Treatment for Brain Injury
DURHAM, N.C. -- Duke University Hospital will begin
enrolling patients in a national study to test whether
maintaining a cool body temperature in brain injury patients
who are already hypothermic when they arrive at the hospital
substantially improves their outcome. Duke is one of nine
medical centers nationwide that will take part in the National
Acute Brain Injury Study: Hypothermia II, a $15.6 million
project sponsored by the National Institutes of Health.
"The classic outcome for a patient with traumatic brain
injury is death or severe disability," said Carmelo
Graffagnino, M.D., a neurologist and lead investigator of the
study at Duke. "The societal implications are tremendous
because most people who sustain this type of injury are in the
prime of their lives. There are steps we can take to improve
treatment and outcomes, but we need to make sure they are safe
by conducting this type of research."
The national study is being led by Guy L. Clifton, M.D.,
chair of the department of neurosurgery at the University of Texas Health Science
Center at Houston. In the first National Acute Brain Injury
Study (NABIS), which began in 1994, Clifton and other
researchers found that inducing hypothermia in patients with
severe head trauma did not have the therapeutic value that
scientists expected. However, 30 percent of patients in that
study were already hypothermic when they came to the emergency
room. In that group, maintaining hypothermia appeared to
improve their outcome. Forty-eight percent of those patients
who were kept cold for a period of time had a good outcome and
were able to live independently. By contrast, only 24 percent
of the hypothermic patients who were re-warmed had significant
recovery. The results of the five-year study were published in
the Feb. 22, 2001 issue of the New England Journal of
To be enrolled in this study, patients must be 16 to 45
years old, have a closed head injury and hypothermia, and be
comatose upon arrival at an emergency room. They also must have
no other significant injuries. Half will be placed in
temperature-controlled suits, which were invented and designed
by UT-Houston researchers.
The Rap Round suits, manufactured by Gaymar Industries,
allow doctors to precisely control and maintain their patients'
body temperatures at 33 to 37 degrees Celsius (91.4 to 98.6
degrees Fahrenheit). After 48 hours, doctors will gradually
re-warm the patients during an 18-hour period.
The other patients will re-warm by themselves with no
medical intervention to raise their body temperature.
"We believe that rapid re-warming, which is currently the
standard of treatment, may actually be toxic to the brain,"
said Clifton. "We will be looking at whether it is better to
let them passively re-warm or maintain hypothermia."
Patients must be enrolled in the study before they start to
re-warm because "there are grave implications if you do not act
immediately to treat the head injury," Graffagnino said.
Because of this, researchers plan to waive consent if a
family member cannot be located within one hour of the
patient's arrival at the hospital. To be in compliance with
federal law and the Internal Review Board at Duke University
Medical Center, researchers are making presentations in the
community to inform residents about the study and explain the
waiver-of-consent issue. The 1994 NABIS was the first study to
test whether waiver of consent was effective and met with
Roughly 1.5 million Americans suffer traumatic brain injury
(TBI) each year. About 50,000 die and another 80,000 of these
patients are permanently disabled. An average of 30 percent of
those patients are hypothermic when they arrive at the
hospital. Hypothermia is often the result of cold weather,
intoxication, small body type or cold intravenous fluids that
are administered at the scene of injury.
"Hypothermia has been of medical interest for years because
we can see that it works far better than drug therapy in animal
models," said Graffagnino. "Duke's intensive care unit is
uniquely suited to participate in this research because we have
a multidisciplinary team that is very well practiced in the
care of patients with TBI."
Duke researchers will hold their first community educational
sessions at 6:30 p.m. on Sept. 23 at the Chapel Hill Public
Library, and at 7 p.m. on Sept. 26 at the Talley Student Center
on the campus of North Carolina State University in Raleigh.
Additional educational sessions are planned but not yet
Other study sites are the University of California, Davis;
the University of California at San Francisco; the University
of Southern California; the University of Pittsburgh Medical
Center; Inova Fairfax Hospital; the University of Mississippi