Primary Fibrinolysis Is Integral in the Pathogenesis of the Acute Coagulopathy of Trauma

Abstract

In Brief Background: The existence of primary fibrinolysis (PF) and a defined mechanistic link to the “Acute Coagulopathy of Trauma” is controversial. Rapid thrombelastography (r-TEG) offers point of care comprehensive assessment of the coagulation system. We hypothesized that postinjury PF occurs early in severe shock, leading to postinjury coagulopathy, and ultimately hemorrhage-related death. Methods: Consecutive patients over 14 months at risk for postinjury coagulopathy were stratified by transfusion requirements into massive (MT) >10 units/6 hours (n = 32), moderate (Mod) 5 to 9 units/6 hours (n = 15), and minimal (Min) <5 units/6 hours (n = 14). r-TEG was performed by adding tissue factor to uncitrated whole blood. r-TEG estimated percent lysis was categorized as PF when >15% estimated percent lysis was detected. Coagulopathy was defined as r-TEG clot strength = G < 5.3 dynes/cm2. Logistic regression was used to define independent predictors of PF. Results: A total of 34% of injured patients requiring MT had PF, which was associated with lower emergency department systolic blood pressure, core temperature, and greater metabolic acidosis (analysis of variance, P < 0.0001). The risk of death correlated significantly with PF (P = 0.026). PF occurred early (median, 58 minutes; interquartile range, 1.2–95.9 minutes); every 1 unit drop in G increased the risk of PF by 30%, and death by over 10%. Conclusions: Our results confirm the existence of PF in severely injured patients. It occurs early (<1 hour), and is associated with MT requirements, coagulopathy, and hemorrhage-related death. These data warrant renewed emphasis on the early diagnosis and treatment of fibrinolysis in this cohort. Although primary fibrinolysis has been recognized as being associated with shock, a defined mechanistic link to the “Acute Coagulopathy of Trauma” has not been well elucidated. Using point-of-care rapid thrombelastography, a measure of the viscoelastic properties of blood, early fibrinolysis was found to be significantly associated with shock, massive transfusions, and hemorrhage-related death. Future studies should focus on the potential for early use of antifibrinolytics to improve survival in this group.