A. R. Smith1, S. Karim1, R. J. Reif1, W. C. Beck1, J. R. Taylor1, B. Davis1, A. Bhavaraju1, M. K. Kimbrough1, K. W. Sexton1 1University Of Arkansas for Medical Sciences,Department Of Surgery, Division Of Trauma And Acute Care,Little Rock, AR, USA
Introduction: The Injury Severity Score (ISS) is an important tool for grading the severity of injury to trauma patients. Major trauma is commonly defined using an ISS threshold of 15 and has been shown to correlate with mortality likelihood, length of hospital stay, and the need for major surgery. Assessing hemostatic function in a timely manner is crucial for these patients in order to reduce the risk of mortality. Rotational thromboelastometry (ROTEM) is a whole blood viscoelastic hemostasis analyzer that allows for the detection of and differentiation between coagulopathies. The purpose of our study is to retrospectively evaluate trauma patients with an ISS greater than 15 who also received ROTEM to determine if ROTEM is a better predictor of mortality than conventional coagulation testing.
Methods: We performed a retrospective review of all trauma patients with ROTEM and an ISS greater than 15 admitted to the emergency department between November 2015 and August 2017. A total of 301 patients met the aforementioned criteria and were included in this study. Univariate and bivariate statistics were performed using JMP Pro (Cary, NC). Each patient was sorted into groups based on their coagulation phenotype (hypocoaguable, normal coagulation, hypercoaguable) for both ROTEM and conventional coagulation tests (Partial Thromboplastin Time [PTT], Prothrombin Time [PT], International Normalized Ratio [INR]) and compared the test results to their relation with mortality. Nominal logistic regression was performed.
Results: For the 301 patients included in the study, significant predictors of mortality included ROTEM APTEM Clotting Time (CT), ROTEM APTEM Alpha Angle, and ROTEM INTEM Clot Formation Time (CFT), with ROTEM APTEM CT being the most significant. On nominal logistic regression, APTEM CT (p=.007), APTEM Alpha Angle (p=.028), and INTEM CFT (p=.037) were the only significant predictors. PTT (p=.059), PT (p=.141), and INR (p=.634) were not significant predictors of mortality in this data set.
Conclusion: ROTEM APTEM Clotting Time, which is the time from start of measurement until initiation of clotting in the presence of aprotinin, a fibrinolysis inhibitor, is a significant predictor of mortality in trauma patients with an ISS greater than 15. ROTEM APTEM Alpha Angle and ROTEM INTEM Clot Formation Time are also significant predictors of mortality, whereas conventional coagulation tests did not have a significant contribution to predicting mortality in this patient population.
