Blood Donation
What is it?
Blood donation is the process of giving blood
to be used for blood transfusions. A person who
gives blood for this purpose is called a donor.
The Food and Drug Administration (FDA) has strict
rules for the collection, processing, storage, and
transportation of blood and blood components.
These regulations are important because they
ensure that infectious diseases are not
transmitted during blood transfusions.
Blood donation is extremely important because
it is the only way to maintain sufficient blood
supplies for medical treatment. That's why local
hospitals, blood banks, and the American Red Cross
sponsor frequent blood drives. Because many people
feel more comfortable knowing the source of the
blood for a transfusion, many donors are friends
or family members of a recipient. This is called a
direct donation, and the blood is stored at the
hospital for a specific patient's use.
How do I prepare for this procedure?
All blood donors are carefully screened for
conditions that would make them poor candidates
for blood donation. If you have hepatitis, AIDS,
certain types of cancer, heart disease, severe
asthma, malaria, bleeding disorders, low blood
pressure, or high blood pressure, you may not
donate blood. You also may not donate if you have
been exposed to the AIDS virus, are pregnant, have
had recent surgery, or are using certain drugs.
All these precautions are in place to protect the
people who might receive your blood. The process
of giving blood, however, is extremely safe.
The facility where you donate will use sterile
equipment so you cannot catch an infection. You
may not give blood more often than once every two
months. If you know you will be undergoing
surgery, you may want to donate your own blood
about a month before your surgery. This is called
an autologous transfusion, and the blood you
donate is stored at the hospital for your use
only. If you need a transfusion during or after
surgery, your own blood will be used.
How is this procedure performed?
Before you donate blood, the healthcare
professional will check your blood pressure,
temperature, and pulse. You will lie down on a bed
or cot, then he or she will tighten a wrapping,
called a tourniquet, on your upper arm to increase
the pressure on the veins in your arm so they will
swell. This makes it easier to identify the larger
veins and to insert the needle into the vein. The
healthcare professional will clean the area where
the needle will be inserted with an antiseptic
wash, then insert a large needle into the vein.
You will feel a slight sting as the needle goes
in, but the rest of the procedure should be
painless. The blood flows through a tube into a
sterile plastic bag that holds around one pint
(450 ml) of blood, also called one unit. People
usually donate one unit at a time. The average man
has 10 to 12 pints of blood in his body, while the
average woman has 8 to 9 pints. A small sample of
the blood you donate is put aside for testing for
infectious diseases. No blood is used until all
test results have shown that it is safe. All
donated blood is also classified and labeled by
type, either A, B, AB, or O, and as RH-positive or
RH-negative. This is because donor blood must be
matched to the recipient's blood type. The sterile
bags, which contain preservatives and an agent
that prevents clotting, are kept refrigerated.
Whole blood is usable for 42 days.
Donated blood can also be broken down into
blood components, which include red blood cells,
white blood cells, platelets, immunoglobulins, or
fresh frozen plasma, which is the liquid part of
the blood. Perhaps you are donating blood because
someone you know needs a blood component like
platelets, which help with blood clotting. A
special instrument can be used to separate your
blood into components, keep the platelets, then
pump the remaining components back into your body.
This procedure is called apheresis.
What can I expect after the procedure?
Some patients may feel light-headed when they
first stand up after donating blood. You will be
given juice to drink and cookies or crackers to
eat to begin replacing fluids and increase your
blood sugar levels. You will be told to drink
plenty of liquids to replace lost fluids and to
avoid strenuous activity for the remainder of the
day. You may feel a little sore around the area
where the needle was inserted, and their is a
slight chance of infection in that area if it
wasn't well cleaned before the needle was
inserted. Your blood volume will return to normal
within hours after donating blood if you follow
the guidelines for drinking liquids. It takes
several weeks, however, to replace donated blood
cells and platelets.
This information has been designed as a comprehensive and quick reference
guide written by our health care reviewers. The health information written
by our authors is intended to be a supplement to the care provided by your
physician. It is not intended nor implied to be a substitute for
professional medical advice.
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