Effects of intravenous administration of tranexamic acid on hematological, hemostatic, and thromboelastographic analytes in healthy adult dogs

Objective: To assess the effects of tranexamic acid (TA) on hematological, hemostatic, and thromboelastographic analytes in healthy adult dogs. Design: Prospective study. Setting: University teaching hospital. Animals: Eleven healthy, staff-owned, adult dogs. Measurements and Main Results: Dogs were administered TA as an IV bolus, followed by a 3-hour constant rate infusion (CRI). Complete blood count, prothrombin time, activated partial thromboplastin time, D-dimer, antithrombin, fibrinogen, and thromboelastography (TEG) were measured prior to, and immediately after TA administration. Vomiting occurred transiently in the first 2 treated dogs, immediately after 20 and 15 mg/kg IV boluses, but not during the CRI. In all other dogs the TA IV bolus dose was reduced to 10 mg/kg, and administered slower, and vomiting did not occur. All measured hemostatic and hematological analytes remained within their reference intervals, however, following TA treatment, significant decreases were recorded in prothrombin time, TEG R and A30 values, Hct, and hemoglobin concentration, while the TEG LY30 significantly increased. Conclusions: Administration of TA as a slow IV bolus at 10 mg/kg, followed by a 10 mg/kg/h CRI over 3 hours to healthy dogs is safe; however, its effect on TEG A30, A60, LY30, and LY60 values was inconsistent with its expected anti-fibrinolytic properties.