The blood circulating in the body is made up of several components: red blood cells, which carry oxygen; white blood cells or leukocytes, which fight infection; and platelets, also called thrombocytes, which assist in the formation of blood clots. The straw-colored liquid part of the blood is called plasma. Management of symptoms related to cancer and cancer treatments may require blood transfusions.
A transfusion is the administration of blood or blood components through a catheter, a tube that enters the body through an intravenous (IV) needle, central venous catheter (CVC), or peripherally-inserted central catheter (PICC). A transfusion can include all or any one of the blood components, and may come from a donor or may have been harvested from the patient prior to therapy.
Before a transfusion can be given, results of blood studies must first be analyzed to help determine which blood component the patient will need. If the patient has signs of anemia and studies show a low red blood cell (RBC) count, then red blood cells will be transfused. When the body does not receive enough oxygen, symptoms of fatigue, dizziness, and shortness of breath can develop.
Patients receiving chemotherapy often develop low levels of red blood cells, a condition called chemotherapy-induced anemia. Patients with this condition will receive donor red blood cells that have been separated from the blood. These harvested red blood cells are called "packed red blood cells" or PRBCs.
For patients who have bleeding problems, studies may show a low platelet count. Low platelet counts develop when platelet-producing bone marrow cells are damaged by chemotherapy or radiation therapy. Certain cancers, such as leukemia, can also cause low platelet counts. For patients who need platelet transfusions, platelets must first be extracted from plasma. Only a small amount of platelets make up plasma. Therefore, several units of donor blood plasma are needed to create one unit of platelets.
Plasma can also be transfused in patients with certain injuries or clotting disorders. When plasma is separated from blood, it can be frozen until it is needed. The thawed plasma used in transfusions is called "fresh, frozen plasma" or FFP.
Once the appropriate type of blood component has been identified, the blood must be tested to make sure it is a suitable match for the patient. Two tests, type and crossmatch, can be used to test compatibility before any blood or blood product from a donor is administered.