Survival Time of Cross-Match Incompatible Red Blood Cells in Adult Horses

Area of Science:

• Veterinary Medicine
• Immunology
• Hematology

Background:

• Transfused red blood cell (RBC) survival is reduced in cross-match incompatible recipients.
• Naturally occurring alloantibodies are rare in horses, leading to inconsistent cross-match testing.
• Cross-match incompatibility is a known risk factor for transfusion reactions.

Purpose of the Study:

• To evaluate the impact of cross-match incompatibility on RBC survival and transfusion reactions in horses.
• To determine if cross-match incompatibility leads to the development of anti-RBC antibodies.

Main Methods:

• A prospective trial involving 20 healthy horses was conducted.
• Major and minor cross-match tests were performed to determine donor-recipient compatibility.
• Biotinylated donor RBC survival was tracked using flow cytometry for 35 days post-transfusion.

Main Results:

• Cross-match incompatibility was significantly associated with decreased RBC survival (P < .001).
• The half-life of incompatible equine RBCs was 4.7 days compared to 33.5 days for compatible RBCs.
• Incompatible transfusions were linked to acute febrile transfusion reactions (P = .0083).

Conclusions:

• Cross-match incompatibility predicts febrile transfusion reactions and shortened RBC survival in horses.
• Anti-RBC antibody production was not observed at 30 days post-transfusion.
• Pre-transfusion cross-match testing is recommended for equine blood transfusions.