Effect of thromboelastography (TEG®) and rotational thromboelastometry (ROTEM®) on diagnosis of coagulopathy, transfusion guidance and mortality in trauma: descriptive systematic review

Introduction: The understanding of coagulopathies in trauma has increased interest in thromboelastography (TEG (R)) and thromboelastometry (ROTEM (R)), which promptly evaluate the entire clotting process and may guide blood product therapy. Our objective was to review the evidence for their role in diagnosing early coagulopathies, guiding blood transfusion, and reducing mortality in injured patients. Methods: We considered observational studies and randomized controlled trials (MEDLINE, EMBASE, and Cochrane databases) to February 2014 that examined TEG (R)/ROTEM (R) in adult trauma patients. We extracted data on demographics, diagnosis of early coagulopathies, blood transfusion, and mortality. We assessed methodologic quality by using the Newcastle-Ottawa scale (NOS) for observational studies and QUADAS-2 tool for diagnostic accuracy studies. Results: Fifty-five studies (12,489 patients) met inclusion criteria, including 38 prospective cohort studies, 15 retrospective cohort studies, two before-after studies, and no randomized trials. Methodologic quality was moderate (mean NOS score, 6.07; standard deviation, 0.49). With QUADAS-2, only three of 47 studies (6.4%) had a low risk of bias in all domains (patient selection, index test, reference standard and flow and timing); 37 of 47 studies (78.8%) had low concerns regarding applicability. Studies investigated TEG (R)/ROTEM (R) for diagnosis of early coagulopathies (n = 40) or for associations with blood-product transfusion (n = 25) ormortality (n = 24). Most (n = 52) were single-center studies. Techniques examined included rapid TEG (R) (n = 12), ROTEM (R) (n = 18), TEG (R) (n = 23), or both TEG (R) and rapid TEG (R) (n = 2). Many TEG (R)/ROTEM (R) measurements were associated with early coagulopathies, including some (hypercoagulability, hyperfibrinolysis, platelet dysfunction) not assessed by routine screening coagulation tests. Standard measures of diagnostic accuracy were inconsistently reported. Many abnormalities predicted the need for massive transfusion and death, but predictive performance was not consistently superior to routine tests. One observational study suggested that a ROTEM (R)-based transfusion algorithm reduced blood-product transfusion, but TEG (R)/ROTEM (R) based resuscitation was not associated with lower mortality in most studies. Conclusions: Limited evidence from observational data suggest that TEG (R) /ROTEM (R) tests diagnose early trauma coagulopathy and may predict blood-product transfusion and mortality in trauma. Effects on blood-product transfusion, mortality, and other patient-important outcomes remain unproven in randomized trials.