Effects of a single subcutaneous dose of enoxaparin on veterinary viscoelastic coagulation monitor variables in healthy cats: Double blind, placebo controlled cross‐over trial

Abstract Background Cats placed on anticoagulant medication require frequent monitoring. The veterinary viscoelastic coagulation monitor (VCM‐Vet) could provide a convenient and cost‐effective monitoring, enabling therapeutic decision making. Hypothesis/Objectives Enoxaparin will lead to changes in VCM‐Vet variables and these will correlate with antiXa activity. Animals Twenty‐one healthy cats. Methods Cats were randomized to receive either enoxaparin (1 mg/kg) subcutaneously or 0.9% NaCl (equal volume) and crossed over with a 7‐day washout period. The investigators were blinded to group allocation until data analysis. Jugular blood samples were drawn at time 0, and 2, 4, and 8 hours after injection for VCM‐Vet analysis within 2 min of collection. Citrated plasma was frozen at −80°C for antiXa activity analysis. A Generalized Linear Model was completed to assess changes between baseline measurements and all time points. Results Significant differences between the enoxaparin‐treated cats and controls at for T0h and T2h were found and presented as mean ± SD for clotting time (enoxaparin, 593.4 ± 78.0 s; control, 448.5 ± 50.3 s, P < .001), clot formation time (enoxaparin, 183.1 ± 41.7 s; control, 155.4 ± 28.0 s, P = .001), and alpha angle (enoxaparin, 52.4 ± 6.1°; control, 56.9 ± 3.7 s, P = .003). AntiXa activity was significantly different between T0 and all other timepoints for the enoxaparin group (P < .001). There was no correlation between changes in clotting time and antiXa activity. Conclusions and Clinical Importance The VCM‐Vet detects a difference at 2 hours after single‐dose enoxaparin administration and it can be useful for anticoagulant therapy monitoring in cats.