Rapid Plasma-Based Screening of Fibrinolytic Activation in Trauma: A Single Center Observational Cohort Study

Background Viscoelastic testing is commonly used to assess fibrinolytic phenotypes in trauma, with values of thromboelastogram (TEG) LY30 >3% considered indicative of hyperfibrinolysis. The ‘Fibrinolytic Activation Screening Test' (FAST) is a rapid assay that detects endogenous tPA- and plasmin-dependent fibrinolytic activation. Objectives To evaluate FAST activity in trauma, and determine its correlation with other indices of fibrinolytic activation, including plasmin-antiplasmin (PAP) complexes and TEG LY30. Methods FAST activity and PAP complexes were assayed in archived plasma samples from 99 trauma patients on presentation. We evaluated the association of FAST activity with four different PAP thresholds (>2,000 ng/mL, >5,000 ng/mL, >10,000 ng/mL, or >20,000 ng/mL) representing increasing degrees of fibrinolytic activation. Results FAST activity was elevated in 65% of trauma patients on admission. By Spearman's rank correlation, FAST activity was strongly correlated with PAP complexes ( r s = 0.74). The strong association of FAST activity with all 4 PAP thresholds was more pronounced with increasing cutoffs, indicating enhanced specificity of FAST activity with greater fibrinolytic activation. TEG LY30 showed no correlation with FAST activity ( r s = -0.07), and no correlation with PAP complexes ( r s = -0.18). In an exploratory analysis, the FAST assay demonstrated good discriminatory performance for in-hospital mortality by receiver operating characteristic (ROC) analysis (AUC 0.8023, 95% CI=0.6417-0.9630). Conclusions The FAST assay is a rapid and specific measure of fibrinolytic activation in trauma.