Which of the following is not routinely performed on a cord blood sample?

The determination of whether an antibody screen is routinely performed on a cord blood sample hinges on the standard practices in blood banking and immunohematology. When examining cord blood, forward ABO typing, Rh typing, and DAT (Direct Antiglobulin Test) are routinely performed to determine the blood group and to assess for potential hemolytic diseases of the newborn.

However, an antibody screen is not routinely conducted on cord blood samples. The primary purpose of an antibody screen is to detect unexpected antibodies that could react with red blood cells from transfusions. In the case of cord blood, the focus is primarily on determining the presence of any Rh or ABO incompatibility due to maternal antibodies already present, rather than identifying any new antibodies. Hence, the other tests mentioned serve to identify the risk of hemolytic disease, while the antibody screen does not play a direct role in that initial assessment for cord blood.