Anticoagulant profile of subcutaneous enoxaparin in healthy dogs

Our study objective was to identify a subcutaneous enoxaparin dosage that provided a consistent anticoagulant intensity in dogs. Our hypotheses were that a dose of 0.8 mg/kg would provide inconsistent anticoagulation, a higher dose would provide consistent anticoagulation over a greater duration of time, and viscoelastometry would effectively monitor the anticoagulant status. Six healthy dogs received two subcutaneous enoxaparin doses (0.8 and 2 mg/kg) for anti‐Xa activity determinations and pharmacokinetic modeling. Based on calculations derived from these results, 1.3 mg/kg, SC, q8 h was administered for seven doses. Target ranges for anticoagulant intensity were defined as anti‐Xa activity of 0.5–1 U/ml, and change from baseline of two viscoelastometric parameters: activated clotting time (ΔACT; ≥40 s), and clot rate (CRpost; ≤20 U/min). Following an initial injection at 1.3 mg/kg, anti‐Xa activity of 5/6 dogs reached or exceeded the target range. Following the final dose, anti‐Xa activity reached or exceeded the target range in all dogs, and ΔACT and CRpost values exceeded target for 2–6 and 4–12 h, respectively. At an enoxaparin dosage of 1.3 mg/kg, SC, q8 h, anti‐Xa activity was consistently above the minimum threshold of the target range; however, the safety of this dosage remains to be determined.