Thromboelastometry for assessment of hemostasis and disease severity in 42 dogs with naturally-occurring heatstroke.

Abstract

BACKGROUND: Thromboelastometry (TEM) provides a comprehensive overview of the entire coagulation process and has not been evaluated in heatstroke-induced coagulopathies in dogs. OBJECTIVES: To determine the diagnostic and prognostic utility of TEM in dogs with heatstroke. ANIMALS: Forty-two client-owned dogs with heatstroke. METHODS: Prospective observational study. Blood samples for intrinsic and extrinsic TEM (INTEM and EXTEM, respectively) were collected at presentation and every 12 to 24&#x2009;hours for 48&#x2009;hours. Coagulation phenotype (hypo-, normo-, or hypercoagulable) was defined based on TEM area under the 1st derivative curve (AUC). RESULTS: Case fatality rate was 31%. Median TEM variables associated with death (P&#x2009;<&#x2009;.05 for all) included longer INTEM clotting time, lower AUC at presentation and at 12 to 24&#x2009;hours postpresentation (PP), lower INTEM alpha angle, maximum clot firmness, and maximum lysis (ML) at 12 to 24&#x2009;hours PP, and lower EXTEM ML at 12 to 24&#x2009;hours PP. Most dogs were normo-coagulable on presentation (66% and 63% on EXTEM and INTEM, respectively), but hypo-coagulable 12 to 24 PP (63% for both EXTEM and INTEM). A hypo-coagulable INTEM phenotype was more frequent at presentation and 12 to 24 PP among nonsurvivors compared to survivors (55% vs 15% and 100% vs 50%, P&#x2009;=&#x2009;.045 and .026, respectively). AKI was more frequent (P&#x2009;=&#x2009;.015) in dogs with hypo-coagulable INTEM tracings at 12 to 24&#x2009;hours. Disseminated intravascular coagulation was more frequent (P&#x2009;<&#x2009;.05) in dogs with a hypo-coagulable INTEM phenotype and in nonsurvivors at all timepoints. CONCLUSIONS AND CLINICAL RELEVANCE: Hypocoagulability, based on INTEM AUC, is predictive of worse prognosis and occurrence of secondary complications.