Planning antepartum directed donations in preparation for neonatal cardiac surgery in the absence of compatible donors

Background: Homozygous inheritance of the R^N haplotype, characterized by the absence of the high frequency antigen Sec, as well as partial C and e antigens, is rare and is associated with potential for alloimmunization. Anti-Sec has been reported to be associated with a risk of delayed hemolytic transfusion reaction and hemolytic disease of the fetus and newborn (HDFN).

Results: We report the case of a 36-year-old pregnant woman with known sickle cell trait (SCT) and homozygous for the R^N haplotype with anti-Sec, anti-c, and anti-e. Morphological ultrasound identified dextro-transposition of the great arteries in the fetus. Neonatal cardiac surgery was planned with cardiopulmonary bypass support. Due to the rarity of this genotype, there were no compatible donors in our registry. For this reason, in addition to two previously glycerolized maternal donations, the mother donated three units during pregnancy and one unit postpartum.

Discussion: This case highlights the many complexities for the blood supplier pertaining to organizing blood donations during pregnancy, the risk of leukoreduction failure and jellification during the deglycerolization process of units from donors with rare blood carrying the SCT, as well as planning the rare-blood inventory and managing expiry dates to provide transfusion support during delivery, neonatal surgery, and the postoperative period. This case also exemplifies the importance of a strong partnership between blood suppliers and medical teams.