Impact of fibrinogen levels on outcomes after acute injury in patients requiring a massive transfusion

Background: For critically injured patients requiring a massive transfusion, the optimal plasma fibrinogen level is unknown. The purpose of this study was to examine the impact of the fibrinogen level on mortality. We hypothesized that decreasing fibrinogen levels are associated with worse outcomes. Study Design: All patients undergoing a massive transfusion from January 2000 through December 2011 were retrospectively identified. Those with a fibrinogen level measured on admission to the surgical ICU were analyzed according to their fibrinogen level (normal [≥180 mg/dL], abnormal [≥101 to <180 mg/dL], and critical [≤100 mg/dL]). Primary outcome was death. Multivariate analysis evaluated the impact of fibrinogen on survival. Results: There were 260 patients who met inclusion criteria. Ninety-two patients had normal admission fibrinogen levels, 114 had abnormal levels, and 54 patients had critical levels. Patients with a critical fibrinogen level had significantly higher mortality at 24 hours compared with patients with abnormal (31.5% vs 5.3%; adj. p < 0.001) and normal fibrinogen levels (31.5% vs 4.3%; adjusted p < 0.001). Patients with a critical fibrinogen level had significantly higher in-hospital mortality compared with patients with abnormal (51.9% vs 25.4%; adjusted p = 0.013) and normal fibrinogen levels (51.9% vs 18.5%; adjusted p < 0.001). A critical fibrinogen level was the most important independent predictor of mortality (p = 0.012). Conclusions: For patients undergoing a massive transfusion after injury, as the fibrinogen level increased, a stepwise improvement in survival was noted. A fibrinogen level ≤100 mg/dL was a strong independent risk factor for death. The impact of an aggressive fibrinogen replacement strategy using readily available products warrants further prospective evaluation.