A crossmatch is a general haematology test conducted to test recipient blood against potential blood products prior to administration. Strictly speaking, a crossmatch is the testing of red cells against serum; there are two types of crossmatch.
Major crossmatch is the testing of recipient serum (or plasma) against a donor unit.
Minor crossmatch is the testing of donor serum (or plasma against) recipient red cells. It is not longer routine because of the use of Packed Red Cells. When packed cells are administered only a small fraction of donor antibodies remain and the dilutional effect all but inactivates them.
Immediate spin crossmatch
An IS crossmatch is a rapid serological major crossmatch conducted by adding dilute donor red cells and recipient serum at room temperature, immediately centrifuging the tube, and then examining for agglutination. It principally detects ABO incompatibility. IS crossmatching id only suitable for patients in whom there is no evidence of clinically significant antibodies (typically two instances).
Electronic crossmatch
An electronic crossmatch is an electronic alternative to immediate spin crossmatch. The New Zealand Blood Service conducts electronic crossmatching.
Anti-human globulin crossmatch
AHG crossmatch is a type of indirect antiglobulin test It is done in patients when an IS crossmatch is not appropriate or when a “full crossmatch” is required.