Association Between Necropsy Evidence of Disseminated Intravascular Coagulation and Hemostatic Variables Before Death in Horses With Colic

Background: Disseminated intravascular coagulation (DIC) is frequent in horses with severe gastrointestinal disorders. Postmortem studies have found fibrin microthrombi in tissues of these horses, but studies relating these histopathological findings with antemortem hemostatic data are lacking. Hypothesis: Antemortem classification of coagulopathy is related to the presence and severity of fibrin deposits observed postmortem in horses with severe gastrointestinal disorders. Animals: Antemortem hemostatic profile data and postmortem tissue samples (kidney, lung, liver) from 48 horses with colic. Methods: Tissue samples were stained with phosphotungstic acid hematoxylin and immunohistochemical methods for histological examination. A fibrin score (grades 0-4) was assigned for each technique, tissue and horse, as well as the presence or absence of DIC at postmortem examination. D-dimer concentration, prothrombin time (PT), activated partial thromboplastin time (aPTT), and antithrombin (AT) activity, as well as the clinicopathological evidence of coagulopathy, were determined from plasma samples collected 0-24 hours before death or euthanasia. Histologic and clinicopathologic data from the same horses were compared retrospectively. Results: No association was found between antemortem classification of coagulopathy and postmortem diagnosis of DIC based on tissue fibrin deposition. None of the hemostatic parameters was significantly different between horses with or without postmortem diagnosis of DIC. There was no association between horses with fibrin in tissues or different cut-offs for D-dimer concentration and postmortem evidence of DIC. Conclusions and Clinical Importance: Abnormalities of the routine clotting profile, including D-dimer concentration, were not useful in predicting histologic evidence of DIC at necropsy in horses with severe gastrointestinal disorders.