Hemostatic capacity of canine chilled whole blood over time

OBJECTIVE: To determine the hemostatic potential of canine chilled whole blood maintained at clinically relevant storage conditions. DESIGN: In vitro experimental study. SETTING: Government blood and coagulation research laboratory and government referral veterinary hospital. ANIMALS: Ten healthy Department of Defense military working dogs. INTERVENTIONS: One unit of fresh whole blood was collected from each of 10 military working dogs using aseptic technique. Blood was maintained in a medical-grade refrigerator for 28 days at 4°C (39°F) and analyzed before refrigeration (day 0) and after (days 2, 4, 7, 9, 11, 14, 21, and 28). MEASUREMENTS AND MAIN RESULTS: Ten units of canine blood were analyzed with whole blood platelet aggregation, thromboelastography, CBC, biochemical analysis, blood gas, and prothrombin/activated partial thromboplastin/fibrinogen assay. Clotting strength of chilled blood was maintained up to 21 days despite significant decreases in platelet aggregation to ADP, collagen, or γ-thrombin, significant prolongation of prothrombin and activated partial thromboplastin times, and reduced speed of clot formation (K time, alpha angle). Fibrinogen concentration, WBC, RBC, and platelet counts did not change over time. CONCLUSIONS: Chilled canine whole blood loses a small percentage of clot strength through 21 days of refrigerated storage. Further research is needed to determine if this hemostatic potential is clinically relevant in hemorrhaging dogs who require surgical intervention or are exposed to traumatic events.