What are platelets?

Platelets are special cells found in your blood that are required to make blood clot. Patients with bleeding disorders, cancer, blood disorders, and others undergoing special treatments need large quantities of platelets as part of their therapy.

For some patients, their body builds up antibodies to fight against what it thinks are "foreign" platelet cells. For these patients, they require careful matching of donor platelets whose platelets so closely match their own that they are accepted readily. Just as red blood cells are divided into four main groups (A, B, O, and AB), it's also possible to match platelet types.

Why are platelets needed?

Platelets are needed by children and adults with life-threatening illnesses such as leukemia, aplastic anemia, cancer, and other diseases of the blood. They need platelet transfusions to help their blood to clot. Because of bone marrow malfunction or chemotherapy treatment, their bodies are unable to produce platelets. Although platelets do not cure their diseases, they help give patients time for a treatment to work or a cure to be found, or even time for a patient to begin to manufacture his or her own platelets once again. Without an infusion of fresh, healthy, donor platelets, the recovery and prognosis for these patients would be uncertain.

Who can donate platelets?

If you meet the criteria to donate whole blood (e.g., HIV-negative, good health, no high risk behaviors, etc.), you also meet the criteria for donating platelets. The only additional restriction on platelet donors is that you cannot use aspirin or anything that contains aspirin for 72 hours before making a platelet donation. The use of ibuprofen (Motrin®, Advil®) is only restricted for 24 hours. Most routine medicines prescribed by your physician, other than antibiotics, are allowed. Each time you donate platelets, medical staff will question you about any medicines you are currently taking.

What are the differences from a whole blood donation?

The main difference between a whole blood donation and a platelet donation, from the donor's point of view is the time it takes for a donation. Because the blood can only be withdrawn and returned at a certain rate, the donation takes about 2 hours instead of the 45 minutes for a routine whole-blood donation.

The donor's blood is processed through an apheresis machine that extracts only the platelets needed and returns the rest of the blood to the donor. Throughout the entire process, your blood fluids and cells are processed entirely with sterile, single-use, disposable tubing, cell bags, and separation units. Your blood cells and fluids never touch the inside of any machine or part. There is no risk of any blood-transmitted diseases.

Unlike a whole blood donation, where a specific amount of whole blood is withdrawn from your body, a platelet donation involves withdrawing whole blood, separating out about 10 percent of the specific platelet cells, and returning the rest of your cells and blood fluids back to your system. Your body replaces your "missing" platelets in about a day or two. Because there is such a quick return of your blood cells to your system, you are eligible to donate up to 24 times per year, generally every two weeks. Also, because you are receiving most of your blood and blood cells back, there is no anemia or tiredness afterward normally associated with whole blood donation. After a platelet donation, you may, if you wish, return to giving whole blood donations, subject to medical limitations imposed by a whole blood donation. For example, after a whole blood donation, you must wait 8 weeks to donate whole blood again. This means you could make up to 6 whole blood donations each year. However, after a platelet-only donation, you can donate whole blood or platelets again in about 2 weeks. Donors who wish to donate only platelets can donate up to 24 times each year.

What is the platelet donation process like?

A typical donation begins when you enter the donation center. You are greeted and asked to fill out the donation record. A quick review of your medical status is done, and your temperature, iron (hemoglobin) level, and blood pressure are checked by a trained medical person. People with high blood pressure may donate when their blood pressure is 150/100 or below even if it is controlled by medication. After the screening, you are taken to a private counseling booth where you will be interviewed to ensure you are qualified to donate. Then, you are taken into the donation lounge. There are three contoured chairs, similar to plush dentists' chairs. Your arms are swabbed with antiseptic iodine preparations and a blood pressure cuff is attached to each arm. The blood donation needle and the return line catheter are quickly (and relatively painlessly) inserted, one in each arm, and the process begins. Blood is withdrawn from one arm, the platelets are extracted from the blood, and then all the blood, minus a small portion of your platelets, is returned through the other arm.

During this continuous process, you and your companion donors can select a group movie or individual movies to watch with stereo headsets. Or, if you prefer, you can talk to your companion donors, watch television with headsets, enjoy music, read a book or chat with the medical staff.

Although your arms are immobilized, the helpful and friendly nurses cater to your every whim (such as providing juice through a straw, snacks or a blanket, if desired). You are also under constant professional supervision by the entire medical team. The time goes very quickly. After donation, you wear a small band-aid and wrap on both your arms for about three hours. And that's it.

Overnight, the blood and platelets you donated are processed, checked for viruses and other potential problems, and then released for use by patients requiring these life-saving blood components.

Can I participate in apheresis locally?

Donors can participate at Madigan Army Medical Center (MAMC). This process takes approximately two hours. To make an appointment, or for further information call 968-190 7 /190 3 .