A female patient needs a whole blood transfusion. In order for transfusion services (the blood bank) to prepare the correct product a sample of the patient’s blood must be obtained for:
A. A complete blood count and differential.
B. A blood type and crossmatch.
C. A blood culture and sensitivity.
D. A blood type and antibody screen.
Correct Answer: B. A blood type and crossmatch.
This is needed to utilize the correct type of donor blood and to match the donor product with the patient. Incompatible matches would result in severe adverse events and possible death. The tests in options 1 and 3 are unnecessary.
Option A: When blood products are ordered to be administered to a patient who requires a transfusion, a series of tests are performed to decrease the risk of an immune-mediated hemolytic reaction caused by incompatible blood.
Option C: The type and screen are the first pretransfusion compatibility tests performed, and they are used to identify the patient’s ABO group and Rh type as well as to detect expected and unexpected antibodies in the patient’s serum, respectively.
Option D: These tests are utilized to determine the patient’s blood type and the presence of antibodies to blood antigens. It does not determine donor blood compatibility with the patient. The crossmatch is the final step of pretransfusion testing as a routine procedure. A portion of donor blood is combined with patient plasma or serum and is checked for agglutination, which would signify incompatible blood. This important step, also known as major crossmatch, serves as the last guard to ensure a safe transfusion.