An ex vivo evaluation of efficacy of refrigerated canine plasma.

OBJECTIVES: To determine thawing times of fresh frozen plasma (FFP), and to evaluate the activity of hemostatic proteins (coagulation factors V, VII, VIII, IX, X, and fibrinogen), clotting times (prothrombin time and activated partial thromboplastin time), and sterility of canine plasma stored refrigerated. DESIGN: Prospective laboratory-based study. SETTING: Veterinary teaching hospital blood bank. INTERVENTIONS: Phase 1: Six units of canine FFP were retrieved from the blood bank and thawed individually in a warm water bath. Time for thaw was recorded in minutes and reported as mean ± SD. Phase 2: One unit of fresh whole blood was collected from 9 dogs and processed routinely. Resulting plasma was divided into 2 aliquots, 1 stored as refrigerated plasma (RP) and 1 as frozen plasma. Samples from the RP were taken at 0, 1, 5, 7, and 14 days and from the FFP at days 0 and 14 for determination of clotting factor activity (V, VII, VIII, IX, and X and fibrinogen) and clotting times. Coagulation factors and clotting times were analyzed using a mixed effects linear model for ANOVA, comparing changes over time as well as differences between groups. For all comparisons, a P value of <0.05 was considered significant. Batch bacterial aerobic and anaerobic cultures of the RP samples were submitted on days 7 and 14 and from the frozen plasma on day 14. MEASUREMENTS AND MAIN RESULTS: Time to thaw for FFP units was 34.7 ± 1.38 minutes. Refrigerated storage resulted in significant decreases in the activity of all clotting factors and a subsequent prolongation in clotting times. However, no values were outside of the reference interval. All bacterial cultures yielded no growth. CONCLUSIONS: Refrigerated storage results in only minor loss of coagulation factor activity in canine plasma. The use of RP, therefore, may be a viable option in high-volume veterinary hospitals for rapid correction of coagulopathy in critical care patients.

Hemostatic changes in dogs with naturally occurring sepsis.

Sepsis is a frequent source of morbidity and mortality in critically ill patients. The goal of this case control study was to measure hemostatic changes in dogs with naturally occurring sepsis. Blood was collected within 24 hours of admission from 20 dogs that fulfilled the criteria for sepsis. Sepsis was defined as histologic or microbiological confirmation of infection and 2 or more of the following criteria: hypo- or hyperthermia, tachycardia, tachypnea, or leukopenia, leukocytosis, or > 3% bands. Culture and sensitivities were performed on appropriate samples from all septic dogs. Twenty-eight control dogs were enrolled on the basis of normal results of physical examination, CBC, serum biochemistry, and coagulation profile. Plasma samples were analyzed for prothrombin time (PT), partial thromboplastin time (PTT), fibrin(ogen) degradation products (FDP), D-dimer (DD) concentrations, antithrombin (AT) activity, and protein C (PC) activity. Data were compared between groups by chi-square or independent t-tests. PC (P < .001) and AT (P < .001) activities were significantly lower in dogs with sepsis compared to controls. Dogs with sepsis had significantly higher PT (P = .007), PTT (P = .005), D-dimer (P = .005), and FDP (P = .001) compared to controls. Platelet counts were not significantly different between groups. Ten of the 20 septic dogs (50%) died, but no association was identified between any of the measured variables and outcome. These findings are consistent with previous studies in animals with experimentally induced disease and in clinical studies of humans. On the basis of these results, further investigation of the role of AT and PC in canine sepsis is warranted.