Current state of transfusion practices for ABO-incompatible pediatric heart transplant patients in the United States and Canada.

Background: ABO compatibility restriction on solid organ transplantation limits organ availability. In an effort to increase organ availability, pediatric ABO-incompatible heart transplants (ABOiHT) are now performed with similar outcomes to ABO-compatible transplants. Transfusion support can be challenging and currently there are no standard guidelines for blood product support, ABO isohemagglutinin (IH) titer cutoffs for transplant eligibility, or therapeutic intervention for these patients. The study aim was to survey current blood bank and antibody reduction practices for pediatric ABOiHT in the United States and Canada.

Study Design And Methods: A Web-based survey was sent to 50 US and Canadian pediatric blood bank directors. Participants were queried regarding pre-, intra-, and postoperative blood product support; ABO IH titer testing; and antibody reduction practices in ABOiHT recipients.

Results: We analyzed 21 responses from US and Canadian centers that perform pediatric ABOiHT. There is wide variation in the type of blood products transfused and the modification of these products among respondents in the pre-, intra-, and postoperative settings. The frequency of testing ABO IH titers, implementing therapeutic intervention, and the type of therapeutic intervention also vary greatly among the institutions.

Conclusion: Transfusion support of children with ABOiHT varies widely among blood banks in the United States and Canada. The choice of blood products and modifications utilized, titer thresholds for organ selection and medical decision points, and antibody reduction strategies are not standardized from center to center. As pediatric ABOiHTs become more common, a better understanding of optimal transfusion support and therapeutic intervention is needed.