2015 ACVIM Forum Research Abstract Program

Voriconazole is released in a sustained manner from PLGA-PEG-PLGA thermogel in vitro. SCS injections of liquid thermogel are feasible in equine eyes and result in formation of a welldefined gel deposit at body temperature. In species such as humans and cats, there is a markedly reduced half-life of transfused red blood cells (RBC) when the donor and recipient blood cross-reacts. Only 10-20% of horses have naturally occurring alloantibodies and cross-match is not always performed prior to whole blood transfusion. We hypothesized that cross-match incompatibility predicts shortened RBC survival time after autologous transfusion in horses. Twenty healthy adult horses were used. Blood type, anti-RBC antibody screen and major and minor cross-match determined 10 pairs. Two pairs were cross-match compatible, and the remainder were incompatible. Donor blood (4L) was collected into citrate phosphate dextrose adenine-1, labelled with NHS-biotin, and transfused into recipients. Post-transfusion samples were collected at 1 hour and 1, 2, 3, 5, 7, 14, 21, 28, and 35 days. Proportions of biotinylated RBC were detected by flow cytometry using streptavidin-phycoerythrin. Cross-match incompatibility was significantly associated with decreased survival time (P < 0.001). The half life of transfused incompatible (cross-match >1+) allogeneic equine RBC was 4.7 days versus 33.5 days for compatible RBC. Cross-match >1+ was significantly associated with febrile transfusion reaction (P = 0.0083). Cross-match testing prior to transfusion is recommended whenever feasible despite the low incidence of naturally occurring alloantibodies in horses.