Hemostatic Analysis of Simulated Gloydius ussuriensis Envenomation Using Canine Blood: A Comparison of Thromboelastography and Classical Coagulation Tests

SIMPLE SUMMARY: Snake bites in companion animals are a major issue and cause life-threatening hemorrhage. Classical coagulation tests are performed to diagnose snake venom-induced coagulopathy; however, these tests often fail to detect early coagulopathy. This in vitro study using snake venom and canine blood aimed to explore the efficacy of thromboelastography, which enabled a comprehensive assessment of the coagulation process, compared with classical coagulation tests. Our results identified the usefulness of thromboelastography in detecting early venom-induced coagulopathy compared with classical coagulation tests. This finding may facilitate decision making in relation to the immediate initiation of anti-venom treatment or suspending unnecessary anti-venom administration, which often causes adverse reactions. ABSTRACT: Snake envenomation may lead to venom-induced consumptive coagulopathy (VICC), usually diagnosed by classical coagulation tests (CCTs), such as prothrombin time (PT) and activated partial thromboplastin time (aPTT). However, the results of CCTs are frequently normal in the initial stages, which may delay anti-venom treatments. Thromboelastography (TEG) is a point-of-care and real-time diagnostic tool that enables a comprehensive assessment of the coagulation process. This in vitro study aimed to determine concentration-dependent changes in canine blood caused by Gloydius ussuriensis (G. ussuriensis) envenomation using TEG and CCTs. Lyophilized G. ussuriensis venom was reconstructed using mouse intravenous lethal dose 50 (LD50(iv)) and serially diluted to 25% LD50(iv), 50% LD50(iv), and 75% LD50(iv) to reproduce VICC at different concentrations. Normal saline was used for the control. We compared TEG values of the reaction time (R), kinetic time (K), rate of clot formation (α-angle), maximum amplitude (MA), fibrinolysis at 30 min (LY30), and global strength of the clot (G) with those of PT, aPTT, fibrinogen, and platelet counts (PLTs). Most TEG parameters, except R and LY30, demonstrated statistically significant changes compared with the control at all concentrations. CCTs, except PLTs, revealed significant changes at ≥50% LD50(iv). Thus, TEG could be a useful diagnostic strategy for early VICC and preventing treatment delay.