Contact: Richard Merritt|
Duke University Medical Center
DURHAM, N.C. – As the national blood
banking community considers limiting the use plasma from female donors
because of a rare but potentially catastrophic lung condition,
researchers from Duke University Medical Center have shown that this
policy change might be premature.
In their analysis of 8,300
heart surgery patients, the researchers found no association between
transfused female plasma and any adverse outcome. In fact, they found a
significant decrease in complications in patients receiving only female
Plasma, which makes up about 55 percent of blood’s
total volume, is the liquid portion of blood that is separated from
oxygen-carrying red blood cells after donation. It is pale yellow in
color and is usually given to patients after surgery to help restore
their blood’s normal clotting ability.
Transfused plasma from
female donors has been implicated as a cause of a rare condition known
as transfusion-related acute lung injury (TRALI), in which the lungs
fill with fluid. The incidence of TRALI is hard to determine, and it is
estimated that it occurs at a rate of 1 in 1,300 transfusions to 1 in
5,000 transfusions. It is the leading cause of transfusion-related
death in the United States.
“Our data showed no deleterious
effect associated with female plasma transfusion, and even pointed
toward the possibility of a protective effect,” said Duke
anesthesiologist Ian Welsby, M.D. Collaborator and co-author Marla
Brumit, M.D., from the Carolinas Region of the American Red Cross,
presented the results of the Duke study at the annual meeting of the
American Association of Blood Bankers in Anaheim, Calif.
red blood cells can easily be separated from whole blood, antibodies
from immune cells remain in plasma products, which is the root of the
problem. Pregnant women develop a specific kind of antibody in response
to carrying a baby, which is genetically half mother and half father.
The more children a woman has, the more of these antibodies are
produced. It is thought that some recipients of transfused plasma from
women react negatively to these antibodies in the plasma.
Because of this apparent risk, the United Kingdom has used only plasma from male donors since 2004.
“TRALI is important and effective preventative steps should be taken to
prevent it; however, we believe that more prospective data needs to be
evaluated prior to enacting a policy such as the one in the United
Kingdom,” Welsby continued. “By focusing on a single rare event, they
may be missing the forest for the trees. The bottom line is that female
donor plasma may not be as harmful as it has been made out to be and
antibodies from female plasma are only one source of TRALI.”
Duke researchers scoured their extensive database of patients who
underwent cardiac surgery over a ten-year period beginning in 1993,
looking for any possible negative effects in patients who received
female plasma. These patients were chosen because surgery and the use
of the heart-lung machine during a procedure are both important risk
factors for developing TRALI.
Of the sampled patients, 25.6 percent received plasma transfusions, of which 44.8 percent came from female donors.
found that the volume of plasma a patient received was associated with
higher mortality, which makes sense, since if you can stop the bleeding
sooner, the patient will do better,” Welsby said. “However, there was
no association between female plasma and death, respiratory
complications or even delayed recovery. These results raise questions
concerning the overall benefit of a broad policy that completely
excludes the transfusion of female plasma.”
were also intrigued by the finding that female plasma may actually
reduce complications after heart surgery. They are planning future
prospective studies to better understand this phenomenon.
there are some plausible reasons supporting the idea that female plasma
may help patients,” Welsby said. “Female plasma contains estrogen and
other hormones that are known to promote blood clotting and have