Interpretation of AABB Standards for pre-transfusion compatibility testing of two-unit red cell apheresis products from the same donation

A Resource Coordinator at a Blood Bank in a Chicago hospital wonders how others interpret AABB Standards 5.15.1 and 5.14.3 with regards to pre-transfusion compatibility testing of Two-Unit Red Cell Apheresis products when both such units from the same donation are received by a hospital's transfusion service. His hospital currently verifies the ABO group on each and every Apheresis RBC component bag as well as the Rh typing for each and every bag labeled as Rh negative. When a patient who has a clinically significant alloantibody requires transfusion, RBC units are screened to find those that lack the corresponding antigens. If, for example they have two Apheresis RBC units from the same donation (Apheresis RBC UNIT A and Apheresis RBC UNIT B) and both units need to be tested for the presence or absence of a particular antigen, both units are currently tested, even though Apheresis RBC UNIT A and Apheresis RBC UNIT B come from the same donor and should have the identical phenotypes. If that same patient is going to be transfused with Apheresis RBC UNIT A and Apheresis RBC UNIT B, a crossmatch would be performed on both of the units, with each unit being crossmatched using an antiglobulin phase.

The inquiring colleague wonders if others feel that the performance of antigen phenotyping and antiglobulin crossmatching on both Apheresis RBC UNIT A and Apheresis RBC UNIT B is necessary, or merely unnecessarily duplicating work? He is fully aware of several safety precautions and the comfort zone that blood bankers try to establish by doing duplicate testing. He has reviewed the new 23rd edition of the AABB Standards which state:

5.15.1 states (regarding Serologic Crossmatch): Before issue, a sample of the recipient's serum or plasma shall be crossmatched against a sample of donor cells from an originally attached Whole Blood or Red Blood Cell segment. The crossmatch shall use methods that demonstartes ABO incompatibility and clinically significant antibodies to red cell antigens and shall include an antiglobulin test as described in Standard 5.13.3.

5.14.3 states: When clinically significant red cell antibodies are detected or the recipient has a history of such antibodies, Whole Blood or Red Blood Cell components shall be prepared for transfusion that do not contain the corresponding antigen and are serologically crossmatch-compatible.

He interprets the standards mentioned above to require serologic crossmatching be done from a segment that is directly attached to each component bag, so that both Apheresis RBC UNIT A and Apheresis RBC UNIT B would require separate crossmatches. However, he wonders if the standards allow sufficient leeway for antigen typing of Apheresis RBC UNIT A to be used in lieu of typing Apheresis RBC UNIT B?

The following comments have been received.

ADDENDA Mar 23, 2005

1. A Blood Bank medical technologist at a Health System in Illinois reports that she and her staff believe that the “duplicate” testing described by the Resource Coordinator at a Blood Bank in a Chicago hospital is necessary, due to the possibility of labeling errors (of the units). Thus, in some Illinois hospitals, even though both units may be from a single Red Cell Apheresis collection, each unit is considered to be a separate entity subject to the same testing requirements as if they were from two different donors.

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