Transfusion of Uncrossmatched Group O Erythrocyte-containing Products Does Not Interfere with Most ABO Typings

Abstract

Background Group O erythrocytes and/or whole blood are used for urgent transfusions in patients of unknown blood type. This study investigated the impact of transfusing increasing numbers of uncrossmatched type O products on the recipient’s first in-hospital ABO type. Methods This was a retrospective cohort study. Results of the first ABO type obtained in adult, non–type O recipients (i.e., types A, B, AB) after receiving at least one unit of uncrossmatched type O erythrocyte-containing product(s) for any bleeding etiology were analyzed along with the number of uncrossmatched type O erythrocyte-containing products administered in the prehospital and/or in hospital setting before the first type and screen sample was drawn. Results There were 10 institutions that contributed a total of 695 patient records. Among patients who received up to 10 uncrossmatched type O erythrocyte-containing products, the median A antigen agglutination strength in A and AB individuals on forward typing (i.e., testing the recipient’s erythrocytes for A and/or B antigens) was the maximum (4+), whereas the median B antigen agglutination strength among B and AB recipients of up to 10 units was 3 to 4+. The median agglutination strength on the reverse type (i.e., testing the recipient’s plasma for corresponding anti-A and -B antibodies) was very strong, between 3 and 4+, for recipients of up to 10 units of uncrossmatched erythrocyte-containing products. Overall, the ABO type of 665 of 695 (95.7%; 95% CI, 93.9 to 97.0%) of these patients could be accurately determined on the first type and screen sample obtained after transfusion of uncrossmatched type O erythrocyte-containing products. Conclusions The transfusion of smaller quantities of uncrossmatched type O erythrocyte-containing products, in particular up to 10 units, does not usually interfere with determining the recipient’s ABO type. The early collection of a type and screen sample is important. Editor’s Perspective What We Already Know about This Topic What This Article Tells Us That Is New

Top down thinking: how uncrossmatched RBCs confounded ABO typing

“…A recent study demonstrated that the ABO type of 665/695 (95.7%) non–group O recipients could be accurately determined on the first type and screen sample obtained by the blood bank after the transfusion of uncrossmatched type O RBC–containing products (i.e., RBCs and whole blood units). However, the likelihood of obtaining a valid ABO type decreased as the number of uncrossmatched group O RBC–containing products increased such that 15% of patients who received more than 10 units did not have a valid ABO type on the first sample . The following is a case report of a patient who received uncrossmatched group O RBCs and whose ABO group was discrepant on a subsequent sample received by the blood bank.…”

“…However, the likelihood of obtaining a valid ABO type decreased as the number of uncrossmatched group O RBCcontaining products increased such that 15% of patients who received more than 10 units did not have a valid ABO type on the first sample. 1 The following is a case report of a patient who received uncrossmatched group O RBCs and whose ABO group was discrepant on a subsequent sample received by the blood bank.…”

Heterogeneity in Approaches for Switching From Universal to Patient ABO Type-Specific Blood Components During Massive Hemorrhage

“…23 More units, however, may be needed to observe these effects during massive transfusion in adults, as recent studies have indicated that while receiving as few as 6 emergency units are sufficient to elicit an ABO-typing discrepancy, only 15% of patients who received more than 10 units of emergency blood have such a discrepancy on their first sample. 24,25 Outside of the AABB Standards, additional guidance regarding the safe transition to type-specific blood components, despite the unique laboratory complexities, is quite limited. Hess et al 26 suggest that each transfusion service should develop a policy that takes into account the number of group O red cells transfused.…”

Tips, tricks, and thoughts on the future of prehospital blood transfusions

“…In a recent case report, 15 a patient received both RhD‐positive and RhD‐negative uncross‐matched LTOWB and RBCs before the sample for pretransfusion testing was collected, and determining her native RhD‐type required employing advanced serological techniques that are generally only available in specialized immunohematology reference laboratories. While receipt of uncross‐matched RBCs or LTOWB does not generally interfere with the determination of the recipient's ABO group if the blood bank has a policy for interpreting and explaining the mixed field agglutination that might be present, 16 having a sample that was drawn before any transfusions are administered would allow the blood bank to have maximum flexibility when selecting the ABO and RhD types of products to issue to the patient once in the hospital, that is, the patient could start to receive ABO and RhD group‐specific units (the requirement for an ABO check type sample notwithstanding) and another immunohematological testing that can only be conducted on pretransfusion samples could also be performed if needed.…”