Effect of emergency department fibrinogen testing on survival of trauma patients receiving blood transfusions

Fibrinogen is the first clotting factor to reach critically low levels during blood loss and its depletion is associated with coagulopathy, increased blood loss, transfusion requirements and mortality after trauma. However, direct measurements of fibrinogen concentration or function are not included in many Emergency Department (ED) trauma laboratory testing protocols. We hypothesized that including a test of fibrinogen concentration in the ED would be associated with increased survival for trauma patients requiring blood transfusions. To test this hypothesis, we performed a single-centre retrospective study of the effect of a resulted fibrinogen concentration measurement performed in the ED on survival of trauma patients receiving blood transfusions within the first 4 h of their hospital arrival. Multivariate logistic regression was used test the effect of a fibrinogen test on hospital survival after adjusting for the influence of INR, injury severity, lowest recorded blood pressure and blood transfusion intensity defined as the number of red blood cell units transfused in the first 4 h or care. Of 11 404 trauma registry individuals from 2016 to 2017, 843 (7.4%) received any blood transfusions within the first 4 h of ED care, of whom 635 (75.3%) had a documented fibrinogen concentration ordered and resulted. Multivariate logistic regression for hospital survival demonstrated a significant interaction effect between the presence of a fibrinogen test and transfusion intensity (Whole ModelP < 0.0001, InteractionP = 0.035). Repeat analysis after stratifying for those individuals receiving more than 4 units of red blood cell units within 4 h of care found that the presence of a fibrinogen test was independently associated with survival only for those receiving more than 4 units [FIB test odds ratio for survival = 3.5 (1.0, 10.8),P = 0.03]. Fibrinogen testing in the ED may be a valuable addition to resuscitation of the trauma patient receiving significant blood transfusions.