Blood Transfusions for Children with Sickle Cell Disease
 |
What are the
risks of stroke in sickle cell children?
Strokes in sickle-cell disease (SCD) children
are a common symptom of their disease, and the risk of
neurological damage and recurrent stroke is high. The best
strategy is to try to prevent strokes from occurring
and recurring. Yet treatments to prevent strokes in SCD
children can be extreme, so it’s important to know whether these
treatments are really necessary.
How can blood transfusions
help SCD children?
A number of factors in SCD children can contribute to strokes,
including increased blood pressure through
arteries leading to the brain, which can only be detected
through Transcranial Doppler (TCD) imaging. Increased stroke
risk can be as high as 40% for three years following abnormal TCD results.
|
Blood transfusions can
provide substantial benefits to children with sickle cell
disease. |
Providing good hydration and preventing sleep
apnea (abnormal stoppage of breathing during sleep) and other
symptoms from SCD can help lower the risk of strokes. But
research indicates that blood transfusions may do the most
to prevent stroke. |
The Stroke Prevention in Sickle Cell Anemia (STOP) trial has
shown that simple or exchange red blood cell transfusions
given every three to four weeks reduce stroke recurrence in
SCD children by about 90%.
How many types of transfusions
are there?
Transfusions can take place in
four methods: simple, exchange, manual, and automated.
The
STOP trial used the simple and exchange methods. In a simple
transfusion, red blood cells are given when hemoglobin
levels fall, or in cases of severe anemia. An exchange transfusion involves removal of the patient’s own blood cells along with
the transfusion, which can help decrease the accumulation of iron
that occurs in chronic transfusion programs.
Manual transfusions are not often used. They are similar to
exchange transfusions, but more tedious and time consuming,
involving removal of 500 ml of blood followed by infusion
of 2 units of donor cells. Automated transfusion methods separate
red blood cells from the plasma of the patient in a rapid
and efficient, but costly, partial-exchange transfusion
that removes blood from the patient, separates and discards the patient’s red blood cells,
and returns
the plasma to the patient, along with donor red blood cells.
What are some
other benefits of transfusions for SCD children?
Blood transfusions help SCD children in numerous
ways. They assist the blood’s oxygen-carrying capacity and
reduce the percentage of red blood cells that carry the sickle
gene. Transfusions have also been shown to ease the symptoms
of SCD children, such as acute chest syndrome (which can resolve
dramatically following an exchange transfusion), ankle ulcers
or delayed puberty, as well as life-threatening clots. Transfusions
can be acute (given briefly prior to surgery), short term
(to assist a healthy pregnancy), or long term (to prevent
strokes).
Do blood
transfusions carry any risks?
Yes. Some risks of transfusions should be
taken into consideration. Transfusions may require catheters or ports
to be implanted in patients with poor
venous access. SCD patients can acquire antibodies to the
transfused blood, or develop febrile and/or hive reactions
with repeated transfusions. Iron overload is a typical risk
with transfusions and can compromise heart and endocrine function,
requiring chelation therapy (a process that binds with the
excess iron in the body so it loses its toxicity) which is
not always effective. Delayed hemolytic transfusion reactions
can occur in patients with antibodies, bringing on fevers,
muscle aches, joint pain, anemia, even strokes and death--the
very things the treatments seek to avoid.
Yet despite the risks, blood transfusions can
provide substantial benefits to children with sickle cell
disease. Blood is costly and sometimes not easily available,
and donors are constantly needed to keep up the supply. Please
click here for more information about donating blood through
the Washington University School of Medicine.
About this Site
Content for this site was written by Thea Griffith,
a research assistant with the Internet Stroke Center. Research contributions and advice provided by Desiree
White, Ph.D., Associate Professor, Washington University
in St. Louis Neuropsychology Laboratory.
Next:
Links for More Information
Last Updated:
October 30, 2006
|