Correlation of rotational thromboelastometry (ROTEM) parameters with platelet count and their ability to predict thrombocytopenia in dogs

The study objectivs were to evaluate the correlation between platelet count (PLT) and rotational thromboelastometry (ROTEM) parameters and to determine ROTEM cut-off values for identification of thrombocytopenia in dogs. Medical records of 113 dogs with concurrent EXTEM (ROTEM activated by proprietary tissue factor), FIBTEM (EXTEM with added cytochalasin D) analysis and PLT were retrospectively reviewed. Signalment, treatment prior to analysis, hematocrit (HCT), EXTEM/FIBTEM maximum clot firmness (MCFEXTEM, MCFFIBTEM), EXTEM/FIBTEM maximum clot elasticity (MCEEXTEM, MCEFIBTEM) and EXTEM maximum lysis (MLEXTEM) were extracted from patient records and ROTEM database. Delta (Δ) MCF was calculated as MCFEXTEM−MCFFIBTEM and ΔMCE as MCEEXTEM−MCEFIBTEM. The PLT was correlated to MCFEXTEM, MCEEXTEM, ΔMCF and ΔMCE using Spearman-Rho analysis. Correlations were further analyzed in thrombocytopenic dogs. The ability to predict thrombocytopenia was evaluated with receiver operating characteristics (ROC). Thirty-seven samples (32.7%) showed thrombocytopenia (97% for all 4 parameters. In conclusion, PLT in dogs correlated moderately but significantly with all evaluated ROTEM parameters. All parameters were able to rule out thrombocytopenia