- Thanks to an unusual loophole in the strict rules of
medical ethics, hundreds of trauma patients in California, Texas and a
few other states will be taking a gamble when ambulances come to scoop
them up after accidents or acts of violence.
-
- Without waiting to get consent, paramedics will inject
a fake blood product into half of the eligible patients chosen to take
part in a new study. The other half will get a routine treatment of transfusion
with saline solution until they reach the hospital.
-
- For now, the artificial blood, known as PolyHeme, isn't
approved for general use. But it will still slip into the veins and arteries
of unconscious patients who won't be able to say no.
-
- "Emergency research in general creates a special
set of circumstances," said Kelly Fryer-Edwards, a University of Washington
medical ethicist whose colleagues across the country are divided over the
wisdom of the blood study. "In a way, all of our usual approaches
to research ethics -- to protecting human subjects, to trying to get informed
consent -- just go out the window."
-
- At stake is a product that could revolutionize emergency
medical treatment and surgery.
-
- It's no secret that donated blood is often in short supply.
Blood banks, often entangled in competition and internal politics, frequently
launch desperate appeals for donations. And even when fresh blood is available,
paramedics and surgeons can't immediately pump it into a hemorrhaging patient.
-
- First, they must check the patient's blood type, a process
that takes time, said Dr. Ernest Moore, chief of trauma surgery at Denver
Health Medical Center, which has been testing PolyHeme for 11 years. "Most
hospitals claim they can do it in 20 minutes, but practically, it's a half
hour, and at many institutions it's 40 minutes to an hour."
-
- The "universal donor" blood, type O-negative,
can be transfused into people of all blood types. However, only 7 percent
of people have that blood type. "There's always a shortage of (O-negative)
in any type of hospital that does a lot of acute care," Moore said.
"It would be impossible to supply that throughout ambulances."
-
- When patients are bleeding heavily, paramedics try to
replace missing blood with infusions of saline solution (salt water). But
saline solution -- the same stuff people use to rinse their contact lenses
-- doesn't carry oxygen like blood and instead just acts as a space filler.
-
- Enter modern artificial blood products, which have been
under development since the 1970s. Researchers are trying to create products
that transport oxygen like blood does, are compatible with all people,
can be stored for long periods (donated blood expires after 42 days) and
won't transmit diseases, said Dr. Stephen A. Gould, chairman and CEO of
Evanston, Illinois-based Northfield Laboratories, which manufactures PolyHeme.
-
- According to Gould, only two artificial blood products
-- PolyHeme and Hemopure, by Massachusetts-based Biopure -- are in the
final phases of research. Hemopure, used in surgeries, is made from cow
blood, while PolyHeme is derived from hemoglobin, a protein found in red
blood cells. Hemoglobin lasts much longer than blood and is a one-size-fits-all
solution because it doesn't include the antigens -- the soldiers of the
immune system -- that arm red blood cells against foreign blood types.
-
- PolyHeme is also thinner than regular blood, which may
make it easier to use in hemorrhaging patients, Gould said, raising the
possibility that it may actually be better than blood in some situations.
"That's a judgment call."
-
- There's another benefit, too, one that has gotten little
attention. While the Jehovah's Witness church discourages transfusions
due to the biblical stricture against the consumption of blood, it has
given its 1 million American members leeway to accept products that are
not derived from the major components of blood. (Other religions, including
the Christian Science church, frown on medicine in general and will not
be affected by the availability of artificial blood.)
-
- While surgeons have tested PolyHeme on at least one Jehovah's
Witness, they have done so after getting permission. The new study, which
began earlier this year, doesn't require consent from patients.
-
- Northfield Laboratories hopes to enlist 20 hospitals
in the one-year study, which will enroll 720 patients. While the company
hasn't publicly listed the hospitals that are taking part or considering
participation, news reports have revealed that they include the Denver
Health Medical Center; University of California at San Diego Medical Center;
University of Texas Medical School in Houston; Loyola University Medical
Center in Maywood, Illinois; Mayo Clinic in Rochester, Minnesota; and Regional
Medical Center in Memphis.
-
- Hemorrhaging patients -- including victims of car accidents
and gunshot wounds -- will be eligible for the study, with the exceptions
of pregnant women and those with serious head wounds. The patients will
be randomly assigned to receive saline solution or PolyHeme.
-
- Each of the hospitals will have to hold community meetings
to educate residents about the study. In Denver, health officials allow
those who don't want to take part to ask for bracelets that would let them
opt out. The Associated Press reported that only one person out of 57 objected
to the study at a community meeting in Illinois near Loyola University
Medical Center.
-
- The hospitals are complying with a federal loophole created
by Congress in 1996. It allows the lifting of rules about informed consent
when research involves emergency medical treatment.
-
- In 1998, a company called Baxter Healthcare launched
the first major study of a blood substitute using the loophole. According
to news reports, nearly half of 52 patients died and the study was halted.
-
- George Annas, a medical ethicist at Boston University,
criticized that study and thinks the people behind PolyHeme are making
the same ethical errors. It's wrong to "treat human beings like animals,
like laboratory animals," he said. "People have a right not to
be research subjects."
-
- The right to opt out by wearing a bracelet isn't enough,
he added, although he declined to offer a better system. "It should
be up to the study sponsor to figure out how to do the study ethically,
not the people who criticize the study."
-
- A prominent advocate of patients' rights says people
should have to wear a bracelet to get into the PolyHeme study, not get
out of it. There's simply no proof that the artificial blood is safe, said
Vera Hassner Sharav, president and founder of the New York-based Alliance
for Human Research Protection. "Therefore, we shouldn't be testing
it in people who cannot say no."
-
- Fryer-Edwards, the medical ethicist at the University
of Washington, looks at things a bit differently. It may be very difficult
to find citizens willing to volunteer for a study of trauma patients, she
said, because people don't like to think about the prospect of an accident.
-
- By enrolling people automatically, she said, "you're
putting the responsibility on the person who wants to opt out, and that's
an extra obligation you've created for them. But you have respected their
autonomy by giving them that choice."
-
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