Blood Transfusion and Donation

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Donating blood

Despite all our medical advances, there is no good man-made substitute for human blood – this is why blood donations are so important. People donate blood for different reasons – some do it for friends, family members, or even themselves. Others donate to help people they don’t even know.

Blood is usually donated at special collection centers. Some centers use vans (often called bloodmobiles) that travel to different areas to collect blood. Some larger hospitals have their own centers to collect and process donated blood. After blood is tested for safety and processed into components, it’s stored in blood banks until needed.

Keeping the blood supply safe

The US Food and Drug Administration (FDA) closely regulates blood to keep the blood supply safe. The American Association of Blood Banks also publishes guidelines for safe transfusions, which its members must follow.

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 “Infections” under the section called “Possible risks of blood transfusions”). People are not allowed to donate blood if their lab tests or questionnaires show that they may be at high risk for certain diseases.

Only sterile equipment is used to collect blood. The needle used to draw blood from your vein has never been used before, and it’s thrown away right after it’s used. Donors cannot get hepatitis, HIV, or any 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 one 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 4 to 6 weeks. You must wait at least 8 weeks between whole blood donations. Some blood components can be donated more often.

Rules 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 (or 16 with parental consent)
  • Weigh at least 110 pounds
  • Not have donated blood within the past 8 weeks (this can be 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. Other health and travel questions are reviewed with each donor in detail. (For a complete listing of eligibility of criteria, check the Red Cross website at

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. You can also contact America’s Blood Centers or the American Red Cross for donation centers near you. (See the “To learn more” section for contact information.)

The donation process

Before giving blood, get a good night’s sleep, eat a well-balanced meal, and drink extra caffeine-free fluids. Many donor centers ask that you bring in a list of all the medicines you are taking and your donor card or other identification.

FDA guidelines require that before giving blood, you must register; have your blood pressure, temperature, and heart rate 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 some diseases. You must also be told details about what donating blood will be like before you decide to actually give blood.

You will sit in a reclining chair or lie on a table. An area on your arm will be cleaned, and a sterile needle put into a vein (usually where your elbow bends). Removing a unit of whole blood usually takes about 10 to 15 minutes. Apheresis donation (described in the next section called “Types of donation”) 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 eat a light snack before leaving.

Although you can resume normal activities soon after giving blood, some centers recommend that you have someone else drive home after you donate. You might feel tired, but this will usually only last a few hours.

Types of donations

There are several types of blood donation.

Volunteer whole blood donation

Most blood donations come as units of whole blood from volunteers who have no connection to the person who will get the blood. Once donated, the units are usually separated into components.

Apheresis donation

Apheresis (a-fur-REE-sis) allows volunteers to donate just one blood component. Blood is drawn out through a vein in the arm, and a machine separates 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 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 platelets pooled 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 for 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 week or so. Different blood centers may have different rules about this.

During the apheresis procedure, donors may feel cold, or they may feel a tingling sensation around the lips and nose, but this goes away once the procedure is completed. (It’s caused by the drug that is 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 (aw-tahl-uh-gus) donation. Autologous donation is most often done in the weeks before you have a scheduled surgery that will likely require blood transfusion. Your own 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. Still, it’s not totally without risk. There’s 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 pay for this. There’s also a need to plan ahead so that you have enough time before surgery to have your blood cell counts go back to normal after your blood has been collected.

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, but you should call ahead to check requirements and schedule the donation. The donor must meet the same requirements as for regular blood donation, and the donor’s blood must match the blood type of the recipient.

Blood from directed donors has not been shown to be safer than blood from volunteer donors and, in some cases, may actually be more likely to cause problems. (For example, see “Graft-versus-host disease” under “Transfusion reactions” in the section, “Possible risks of blood transfusions.”)

The same types of testing are 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 might not be covered by health insurance. If the person the blood was intended for doesn’t need it, some blood banks will use it for someone else. In others, it may be thrown out.

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’s 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: 10/07/2013
Last Revised: 10/07/2013