Most people know that donating blood is a selfless, generous gesture. And most people know that donated blood is an essential element in modern medicine; it saves thousands of lives every year. But what many people don’t know is that there are more ways to donate than by just giving whole blood, and these other types of blood donation are vital in meeting the critical needs of certain patients.
When blood is donated, it is separated into the various components—platelets, plasma, and red cells—for specific medical needs. But separating blood in the laboratory after a donation is inefficient. For instance, only two tablespoons of platelets are collected in the lab from a whole blood donation; it takes six donations (six units of blood) to provide a single platelet transfusion this way.
Enter modern technology. Nowadays there’s a really efficient process for extracting components from blood. It’s called apheresis, and it utilizes a machine which separates the blood during the donation. In the case of platelets, for example, one apheresis blood donation can provide enough platelets for one complete transfusion. That’s six times the amount collected in the laboratory from a whole blood donation. The machine which separates the blood is programmed to remove specific amounts of the chosen blood component, and then it returns the rest of your blood back to you—through the same sterile tubing and needle. You only get stuck once.
Apheresis donation is safe. The amount of platelets, plasma, or red blood cells collected won’t affect your health, though it’s usually a good idea not to engage in strenuous exercise or heavy lifting the rest of the day. Your body will replace the platelets you donate within 24 hours and the donated plasma within two to three days. All the equipment is sterile and is used only once and discarded. Depending on the type of donation, it will take one to two hours of your time.
I spoke with Sarah Fleck, a graphic designer with Hunt Advertising in Odessa, who donates via the apheresis procedure regularly at United Blood Services in Midland. She said that the level of comfort is the same as with a regular blood donation, but that occasionally some people get a bit cold because of the temporary change in the makeup of their blood. But there are always blankets at the ready, and the orange juice and cookies after the procedure are a welcome snack. She says that they tell you what component (platelets, plasma, etc.) they need most, and that she’s happy to be able to help with that need.
I’m throwing around terms like plasma, platelets, and red cells like I really know what I’m talking about. I don’t, but I’ve done some homework and can give you some details about this miraculous red liquid that keeps us all alive. Blood is constantly circulating in the body, providing it with nutrition, oxygen, and waste removal. The average person carries about five liters (about 5¼ quarts). As I’ve mentioned, blood contains several components; the major ones are red blood cells (which carry oxygen to the tissues), white blood cells (which fight infection), platelets, and plasma.
Plasma is a clear, straw-colored liquid that makes up about 55 percent of the blood. It is 90 percent water (which is one reason we should stay well-hydrated); the remaining 10 percent comprises protein molecules (over 700 different proteins!), including enzymes, clotting agents, immune system components, plus vitamins, hormones, glucose, and other dissolved nutrients. Plasma carries the goods—the platelets and the red and white blood cells—and keeps everything moving through the circulatory system. It provides a “storage area” for fluids in the body. Plasma helps maintain blood pressure, helps blood to clot, and it helps heat and cool the body. It is frozen after collection and can be stored for up to a year. After it’s separated from blood cells, plasma for patient use is utilized in one of two directions—one for blood transfusions (burns, liver conditions, and severe blood infections are examples) as fresh frozen plasma and the other for fractionation, to be separated further into its many individual proteins for specialized medical use, such as coagulants, human albumin solutions, and immunoglobulins.
Platelets, the smallest of the blood cells, help control bleeding. They have a short life, surviving only about ten days in the circulatory system before being removed by the spleen. How they work is truly fascinating. These plate-shaped cells benignly travel through the body until a blood vessel becomes damaged (when you get a cut). Platelets then receive a signal from the damaged vessel and collect at the site to go to work. When they become “activated” by this signal, platelets change their form; they morph into a spider-like shape—a rounded body with long legs, or tentacles. Becoming sticky and using their spider “legs,” these cells bind themselves to each other to plug any breaks in the blood vessel. At the same time they activate substances in plasma to form a clot to stanch the bleeding. Platelets, when exposed to air, also help a scab to form over the wound. The donation of platelets is critical in medicine because they can be stored outside the body for only five days. Cancer and transplant patients, traumatic injury or burn victims, and open heart surgery patients are examples of people who require platelet transfusions.
There’s one more type of apheresis procedure to mention briefly, that of double red blood cell donation. It’s similar to a conventional whole blood donation, except the apheresis machine is used to extract two units of red blood cells and then returns your plasma and platelets back to you. Red cells are the most transfused blood component, which means that the demand is great, especially from Type O and Rh-negative donors. Potential donors need to meet slightly higher hemoglobin and body height/weight requirements than other donors.
If you have Type AB blood, you may get the royal treatment when you donate, because your blood is rare (only about 4% of the population has Type AB), and your plasma is the universal one; it will work with anyone, regardless of blood type. They really want your blood.
Donors must be at least 17 years old, weigh at least 110 pounds, and be in good health. You cannot have taken aspirin within 48 hours of donating. To donate via apheresis, you must pass a medical exam and extensive medical screening. You can’t test positive for hepatitis nor HIV, and your daily diet should include 50 to 80 grams of protein. Plasma and platelets can be collected simultaneously; however, you can donate platelets more frequently (up to 24 times a year) than plasma (up to 13 times a year). There are a few more things to consider, and the blood donation center will be happy to fill you in.
Donating blood is easy. You relax while the blood is collected; then get a snack and take it easy for the rest of the day. The demand for donated blood is always high, and someone out there will be very grateful they survived because they received your blood. Who would ever think it’s this easy to save lives?