Blood Donation

In 1667, just 40 years after scientists discovered how the circulatory system works, doctors performed the first recorded transfusion. A teenage boy with a fever received nine ounces of lamb’s blood. The world’s second transfusion — also with lamb’s blood — was to a “mildly melancholy insane man.” Both patients survived. But transfusion was plagued by guesswork and only occasional success until 1901, when Dr. Karl Landsteiner discovered and classified the different blood types. Today, transfusion is an invaluable practice in hospitals, with 43,000 pints of donated blood used each day in the US and Canada.

What are the different types of donation?

Red blood cells

Giving red blood cells is the simplest, quickest, and most common type of donation, and usually what people mean when they talk about “giving blood.” Through a needle in the arm of your choice, technicians will draw roughly a pint of your blood in about 10 minutes. People with O-negative blood are generally considered “universal red cell donors,” meaning that any patient in need can receive their blood, and those with O-positive blood can donate to the majority of people, so their blood is also always needed. Red blood cell donors can give every 56 days — donating more often can result in anemia.

Red blood cells are most often used in patients with chronic anemia or massive blood loss from accidents, other traumas, and surgery. Red cells — particularly those from minorities — are crucial for children with sickle cell anemia because most are African American and their blood is more likely to match certain proteins in a minority donor’s blood, according to the American Red Cross.


Plasma accounts for 55 percent of your blood and is 90 percent water. Plasma is the “river” by which red blood cells, white blood cells, and platelets travel throughout the body, and has important clotting properties. Anyone can give plasma, but individuals with blood type AB-positive are universal plasma donors, so they’re encouraged to give plasma instead of red cells.

Because your body makes plasma much more quickly than red cells, you can donate it as often as once a month. Plasma donation takes at least 30 minutes, and involves separating your blood components in an apheresis machine. Plasma is spun out in the machine’s centrifuge and fed into a bag, then everything but the plasma is returned to your body. Doctors use plasma in hemophilia emergencies, accidents or surgery involving severe bleeding, and liver failure.


Platelets are responsible for blood clotting. Like plasma donation, platelet donation also uses an apheresis machine, but requires many more cycles to draw out the desired components, making the process close to two hours long. Platelet donors are eligible to give every 48 hours, but should not donate more than 24 times a year. No particular blood type is preferred.

Platelets are used to treat patients with leukemia and aplastic anemia (when bone marrow stops producing blood cells), as well as those who are undergoing chemotherapy or recovering from organ or bone marrow transplants.

Many medical procedures use all blood components. For example, a typical organ transplant requires 40 units (pints) of red blood cells, 30 units of platelets, and 25 units of plasma.


Marrow, the tissue inside bones, manufactures red blood cells, white blood cells, and platelets. Diseases that attack the marrow, such as leukemia, threaten the body’s ability to produce these crucial blood components. Easily the most grueling of donations, donating marrow requires anesthesia and often causes hip pain for up to two weeks. However, giving marrow is also probably the most profound of donations: On a given day, about 6,000 patients are waiting for a marrow transplant, and without a match, they may not survive. (Matches tend to be found within ethnic groups, so there’s a particular need for minority marrow donors.)

Is blood donation safe?

In the United States it is. All needles are sterile and thrown away immediately after each use. As for apheresis — the process used to collect platelets and plasma — a single-use plastic kit is used for each donation, ensuring that your blood never comes in contact with the machine or gets contaminated with someone else’s blood.

What should I do to prepare?

Every blood bank will offer suggestions, but in general:

  • Eat a solid meal. It’s also smart to be in good shape all around: Get a good night’s rest and don’t drink too much alcohol the night before.
  • Don’t eat a lot of fatty foods in the 12 to 24 hours before you give. Blood that’s high in fat can cloud testing and render your donation unusable.
  • Drink a lot of water in the 24 hours before donating, especially if you’re giving plasma.

How do I know whether I’m eligible to donate?

Before you donate, technicians at the blood bank will give you a quick mini-physical to measure weight, temperature, heart rate, and iron level.

You should also be prepared to answer a long questionnaire to determine the quality and safety of your blood, and then answer several more questions an interviewer will ask you in person. The questions cover a bit of everything, from the mundane to the offbeat to the personal. It’s important to answer all the questions honestly, even if they seem odd, because they’re designed to keep the blood supply safe. You’ll be asked about your past and present health and lifestyle, as well as your recent travels. The American Red Cross offers information about eligibility guidelines and what to expect. Keep in mind that some criteria may vary from bank to bank. If your blood bank has a Web site, check that out, too.

Only 60 percent of the population is eligible to donate because of past or current illness or other less obvious factors, like not weighing enough (the minimum is 110 pounds) or having gotten a tattoo in the last 12 months. The pool of eligible donors has shrunk in recent years, says Dennis Crader, an apheresis technician at Blood Centers of the Pacific in downtown San Francisco, because of diseases like HIV.

Should I take it easy after giving blood?

Definitely. Even if you feel fine, don’t overdo it. You just did a good deed, so give yourself a break. You’ll want to hang around the center for about 10 minutes before going on your way. Take advantage of the snacks and juice provided to get your blood sugar back up. It’s probably not a good idea to walk very far after leaving, so plan to take a bus or cab home. If you smoke, don’t light up for at least a half hour. Eat a big dinner and avoid drinking alcohol, and avoid exercise that day. And, unless you need to count your calories closely, definitely redeem the free ice cream coupon, which is often a perk of donating!

Will I be paid for my donation?

Contrary to popular opinion, the answer is usually no, although there are some banks around the country that do pay for specific types of donations. According to Crader, most of these paying banks do not use the donated blood for transfusions but for research or other scientific purposes. Blood banks generally don’t pay for donations because they want to discourage people from lying to get paid for their donations.

What is donated blood tested for?

Once your blood is drawn and bagged, it will be shipped to a lab, where it’s tested for several different conditions (including syphilis, Hepatitis B and C, and HIV) in order to determine its safety.

Nucleic Acid Testing (NAT) is a relatively new screening process now used on all donated blood. For example, the test is able to identify the HIV virus sooner than tests that detect disease-fighting antibodies instead of the actual virus. Blood banks are hoping that NAT will expand the eligible pool of donors.

If any of the tests are positive, you will be notified confidentially by mail — never by phone — within four weeks. If you’re deemed ineligible to give, your name may be added to a confidential list of potentially unsafe donors. In order to protect your privacy, the specific reason will not be listed.

How long does donated blood stay usable?

Platelets, which must be stored at room temperature, have a shelf life of only about five days. Red blood cells are refrigerated after donation, and can last up to 42 days. Plasma, which can withstand being frozen, remains usable for up to a year. During the journey from you to its eventual recipient, your blood is kept quite safe in a blood bag designed to survive a 2,000-foot drop.

Since there’s always a demand for all donated components, you can be pretty confident that your blood will be put to potentially lifesaving use in a matter of days.

What is an easy way to donate?

According to America’s Blood Centers, corporate blood drives are the biggest generators of blood volume. If you can get enough people in your company to commit, the blood bank will even bring a mobile donation center to you. Travel writer Randy Antin had a truck from Blood Centers of the Pacific brought to his office in downtown San Francisco, where he said he had little trouble filling 40 slots. The blood bank printed up flyers and posters for the drive, had part of the busy financial district street shut down, and offered free Ben & Jerry’s ice cream coupons to all donors.

“If you make it convenient for them, people are willing to donate,” says Antin. “[At my office], I think they just needed that little push.” Even the company president ended up donating. Antin also became friends with a few coworkers he had never met before.

If you don’t have the numbers to bring in a truck, there are other ways to get a group together. Tom Young, a product manager in San Francisco, motivated eight of his company’s 29 employees to visit the blood bank together during the week of the first September 11 anniversary. Then, in 2003, he arranged for Blood Centers of the Pacific to set up shop in an empty office at his building. Twenty-three people volunteered to donate.

“It was a good opportunity to reflect on September 11 without immersing yourself in the tragedy again. I think as a group, we felt like were doing something for the community, something that served a purpose,” Young said.

If you’re ineligible to donate blood but still want to lend a hand, most blood centers have opportunities for volunteers to do everything from registering donors to handing out juice and cookies after donations.

Further Resources

If you’re going to give blood, you should know what to expect. The American Red Cross has a wealth of information.
To sign up to give blood:

Blood Centers of the Pacific: 888/393-GIVE (You can also make an appointment online at
American Red Cross: 800/GIVE-LIFE;
America’s Blood Centers: 888/USBLOOD;

National Marrow Donor Program: 800/MARROW-2;


Public Broadcasting System, “Red Gold,”

America’s Blood Centers, “History of Blood Banking,”

American Red Cross, “Donating Blood,”

America’s Blood Centers, “Facts About Blood Donation,”

“Blood Banks Issue Urgent Appeal,” Associated Press, Jan. 14, 2003

Interviews with Dennis Crader, apheresis technician, Blood Centers of the Pacific, November 2002 and February 4, 2003

Interview with Randy Antin, January 31, 2003

Interview with Tom Young, February 3, 2003

American Red Cross. 50 Quick Facts: Facts about blood needs.

National Marrow Donor Program. The Need for Donors.

American Red Cross. FAQs About blood and Blood Needs.

© HealthDay

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