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Despite all our medical advances, there is still no good
man-made substitute for human blood, which is why blood donations are
still so important. People donate blood for different reasons -- some
do it for friends, family members, or even themselves. Others volunteer
so that they can help people they don't even know.
Blood is usually donated at special collection centers. Some
centers use vans (bloodmobiles) that travel to different areas to
collect blood donations. Some larger hospitals have their own centers
to collect and process donated blood. After blood is tested for safety
and processed into components, it is sent to hospital blood banks,
where it is stored until needed.
Keeping the blood supply safe
In the United States, all blood centers follow careful
procedures to keep the blood supply safe. Everyone who comes in to
donate is asked many questions and has a chance to say whether their
blood may be unsafe for any reason. Also, previous donation records and
lists of ineligible donors are checked. Lab tests are done to look for
blood that might transmit diseases (described in "Possible risks of
blood product transfusions," above). People are not allowed to donate
blood if their lab tests or questionnaires show that they may be at
high risk for certain diseases.
In response to learning that TRALI is linked to certain donor
antibodies, blood banks are now screening donors to avoid transfusing
plasma from people who are likely to have these antibodies. Other parts
of the blood are used as usual, but the donors' plasma is not given to
patients -- it is used to make medicines.
The U.S. Food and Drug Administration (FDA) considers blood a
"biologic" (much like a drug) and closely regulates it to ensure the
safety of the blood supply. The American Association of Blood Banks
also publishes guidelines for safe transfusions, which its members must
follow.
Donating blood is safe
Rules on who can
donate help protect the donor as well as the recipient
Aside from protecting those who receive donated blood, rules
are also in place to protect people who want to donate. Although
guidelines can vary slightly by state and facility, for the most part
donors must:
- be healthy
- be at least 17 years old
- weigh at least 110 pounds
- not have donated blood within the past 8 weeks (shorter for
most apheresis donations)
- not be taking antibiotics
People who are taking "blood thinners" or certain drugs that
are used to treat acne, baldness, or an enlarged prostate may not be
able to donate unless they've stopped the drug for a few days or weeks.
People who have taken certain drugs for psoriasis or taken products
made from human plasma or tissues may be kept from donating blood even
longer. There are other health and travel questions that are reviewed
with each donor in detail. (See "The
donation process" below)
Giving blood is extremely safe
Only sterile equipment is used to collect blood. The needle
used to draw blood from your vein has never been used before, and it is
thrown away right after it is used. Donors cannot get hepatitis, HIV,
or other infections or diseases from giving blood. Reactions from
donating are rare and are almost always minor when they do happen. If
you are healthy, you can donate a unit (about a pint) of blood without
harm because a unit is a small part of your total blood volume. Your
body will replace the lost fluid within a day, and your bone marrow
will replace all of the blood cells, usually within a couple of weeks.
If you are interested in donating blood, contact the American
Association of Blood Banks (AABB) for a list of member institutions, or
visit their online blood bank locator. Or you can contact America's
Blood Centers or the American Red Cross for donation center locations
near you. (See the "Additional
resources" section for contact info.)
The
donation process
Before giving blood, get a good night's sleep, eat a
well-balanced meal, and drink extra fluids that are caffeine-free. Some
donor centers ask that you bring in a list of all the medicines you are
taking.
FDA guidelines require that before giving blood, you must
register, have your vital signs checked, answer health questions, and
get a blood test (usually by sticking the finger for a few drops of
blood). The center will have you fill out a questionnaire, asking about
certain behaviors or travel that might put you at increased risk for
certain diseases. You must also be informed about donation before you
decide to donate and actually give the blood.
You will be asked to sit in a lounge chair or lie on a table.
An area on your arm will be cleaned, and a sterile needle put into a
vein. Removing a unit of whole blood usually takes only about 10 to 15
minutes, while apheresis donation (described below in the section, "Types of donations")
may take 2 hours or longer.
Once your blood is taken, you will be asked to stay for a
short time to make sure you are feeling well. During this time you are
encouraged to drink fluids such as fruit juice and to eat a light snack
before leaving. The whole process, from registration to snack, takes
about an hour. Although you can take part in normal activities soon
after giving blood, some centers recommend that you have someone else
drive home after you donate. You may feel tired, but this will usually
only last a few hours.
Types
of donations
There are several types of blood product donations.
Volunteer whole
blood donation: Most blood donations come as units of
whole blood from volunteers who have no connection to the person who
will receive it. Once donated, the units are usually separated into
component parts.
Apheresis
donation: Apheresis allows volunteers to donate just one
blood component. Blood is drawn out through a vein in the arm, and a
machine separates out the needed component (usually platelets, although
red blood cells, white blood cells, and plasma can also be collected
this way). The rest of the blood is then returned to the donor, usually
through a vein in the other arm. This procedure usually takes 2 or more
hours.
The advantage of this type of donation is that, since most of
the blood is returned, a large amount of a needed component can be
collected. Patients who need many platelet transfusions, such as some
cancer patients, are exposed to fewer donors in this way than they
would be from pooled platelets coming from many donors. This cuts down
on the risk of both transfusion reactions and infections.
As with whole blood donation, apheresis donors should:
- get a good night's sleep
- eat a well-balanced meal
- drink extra caffeine-free fluids before donating
Since aspirin makes platelets less useful to a transfusion
recipient, donors are usually asked not take aspirin within 36 hours
before donation. The same FDA guidelines as those for whole blood
donation must be followed. Unlike whole blood donors, those who give
platelets or plasma via apheresis usually can give again in a couple of
weeks. Different blood centers may have different rules about this.
During the apheresis procedure, donors may feel a slight
tingling sensation around the lips and nose, but this goes away once
the procedure is completed. (It is caused by the drug used to keep the
blood from clotting in the machine.) Other side effects, such as
feeling tired, are much like those from whole blood donation.
Autologous blood donation: Donating your own blood for later
use is called autologous (meaning "from the self") donation. Autologous
donation is most often done in the weeks before you have a scheduled
surgery that will likely require blood transfusion. The blood can then
be used during or after the operation to replace any blood you may have
lost. This is generally thought to be the safest form of blood
transfusion because you're getting your own blood back. But it is not
totally without risk. There is always the very small chance that
bacterial contamination or clerical errors can happen. People who
aren't able to donate blood for others may still be able to donate
blood for themselves.
There is a processing fee for collecting, testing, storing,
and delivering each unit of autologous blood. Be aware that your health
insurance may not fully reimburse you for this cost.
Directed
donation: Donating blood for a family member, friend, or
other specified patient is called directed
donation. This can be done at any blood donation center.
The donor must meet the same requirements as for regular blood
donation, and the donor's blood must be compatible with (match the
blood type of) the recipient.
Blood from directed donors is not usually any safer than blood
from other volunteer donors and in some cases may actually be more
likely to cause problems. (See "Graft-versus-host disease" under
"Transfusion reactions" in the Possible
Risks of Blood Product Transfusions section) The same types
of testing are still done on blood from directed donors. As with
autologous donation, there is a processing fee for collecting, testing,
and delivering each unit of directed donor blood. This fee may not be
fully reimbursed by health insurance.
Paid donation:
Blood from paid donors cannot be used in the United States for
transfusion purposes. Plasma is the only component for which donors are
sometimes paid, and it is taken by the apheresis method. Plasma can be
treated for safety in ways that blood cells cannot. Plasma taken from
paid donors is generally treated and processed by pharmaceutical
companies into drugs. It cannot be transfused in the form of
cryoprecipitate or fresh frozen plasma.
Last Medical Review: 07/13/2009
Last Revised: 07/13/2009
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