Advances in Transfusion Medicine for Veterinary Patients

Red blood cell (RBC) transfusions are common life-saving treatments for hypoxic anemia both for human and veterinary patients. For many years, allogenic blood transfusion (ABT) was the mainstay of transfusion medicine due to efficacy and relative availability, especially perioperatively and in emergency trauma cases. However, ABTs are no longer the preferred treatment for anemia in human and veterinary medicine. There has been a shift away from liberal or unnecessary transfusions due to the inherent risks, and a new focus on more conservative protocols using patient blood management. Similarly, in veterinary medicine, there has been an increase in awareness of risks associated with ABT and adoption of more conservative transfusion principles. Alternative transfusion methods have been explored to reduce the need for ABT perioperatively. Specifically, autologous blood transfusion (autotransfusion) via cell salvage washing (CSW) is an effective, safe alternative used perioperatively without risk of incompatibility. However, contraindications have limited the use of cell salvage in the past. Leukoreduction filters (LRF) have been investigated to mitigate such contraindications by removing contaminants, specifically bacteria. LRF has proven effective to remove bacteria in human blood. Our proof-of-concept study showed that CSW in combination with LRF reduced bacterial contamination in dog blood. Therefore, CSW and LRF could be used to remove bacterial contamination of blood for intraoperative autotransfusion in veterinary patients. Despite our best efforts, ABT cannot always be avoided. A major component of ABT that contributes to transfusion-associated complications is storage lesion. Storage lesions and secondary detrimental effects on patient outcome have been well described in the literature. Microparticles (MPs) derived from blood cells have been identified in stored ABT and are considered a storage lesion. Prestorage leukoreduction has been shown to decrease, not eliminate, the formation of MPs. Prestorage leukoreduction is a standard transfusion protocol in human medicine but not veterinary medicine. Therefore, we investigated the ability of a LRF to remove MPs from stored dog blood prior to transfusion. We concluded that the LRF used in this study did not remove MPs from stored dog blood post-storage. However, based on the limitations, further studies are indicated to validate this conclusion