Background- Bleeding tendencies and platelet dysfunction occurs with uremia. Impaired primary hemostatic function in dogs with acute kidney injury (AKI) and chronic kidney disease (CKD) has clinical implications, however, its comprehensive evaluation is limited. Objectives- To assess hemostasis, including determination of platelet function and thromboelastometry of dogs with AKI and CKD Animals- Client-owned dogs (n=36; AKI, 18; CKD, 12; healthy controls, 6) presented to a teaching hospital. Methods- Prospective study. PFA-200 closure times using collagen-ADP and collagen-epinephrine agonists were determined. Hemostasis was evaluated by PT, aPTT, antithrombin activity, D-dimer and fibrinogen concentrations, and thromboelastometry. Results- Collagen-ADP closure time of the AKI group [median, 139 seconds (range, 71-301)] was longer compared with the CKD [median, 77 seconds (range, 56-235), P=0.042] and control [median, 70 seconds (range, 52-79), P=0.003]. Additionally, the proportion of dogs with prolonged closure time was higher in the AKI compared with controls for both collagen-ADP and collagen-epinephrine (78% vs 0%, P<0.001 and 44% vs 0%, P=0.05, respectively). Collagen-ADP closure time was correlated with creatinine (r=0.61, P< 0.002) but not with platelet count or clotting times. The thromboelastometry clot formation time was lower while its α-angel and maximal clot firmness were higher in the AKI and CKD groups compared with controls. Antithrombin activity was lower (P=0.001), while fibrinogen was higher (P=0.005) in dogs with AKI compared with controls. Conclusions and clinical importance- Dogs with AKI show hemostatic abnormalities, including hypercoagulability in face of platelet dysfunction. Therefore, comprehensive assessment of hemostasis, including platelet function, is recommended prior to invasive interventions.
