Introduction: Uncontrolled hemorrhage accounts for up to 40% of trauma-related mortality. Previous reports demonstrate that decreased fibrinogen levels during traumatic hemorrhage are associated with worse outcomes. Cryoprecipitate is used to replace fibrinogen for patients in hemorrhagic shock undergoing massive transfusion (MT), though the optimal ratio of cryoprecipitate to fresh frozen plasma (FFP), packed red blood cells (PRBCs), and platelets remains undefined. The purpose of this study is to investigate the effect of admission fibrinogen level and the use of cryoprecipitate on outcomes in trauma patients undergoing MT.
Methods: A prospective practice management guideline was established to obtain fibrinogen levels on adult trauma patients undergoing MT at a level I trauma center from December 2019 to December 2021. Ten units of cryoprecipitate were administered every other round of MT. Thromboelastography (TEG) was also obtained at the initiation and completion of MT. Patient demographic, injury, transfusion, and outcome data were collected. Hypofibrinogenemic (<200 mg/dL) patients at initiation of MT were compared to patients with a level of 200 mg/dL or greater.
Results: A total of 96 out of 130 patients met criteria and underwent MT with a median admission fibrinogen of 170.5 mg/dL. Hypofibrinogenemia was associated with elevated INR (1.26 vs 1.13, P < .001) and abnormal TEG including decreased alpha angle (68.1 vs 73.3, P < .001), increased K time (1.7 vs 1.1, P < .001), and decreased max amplitude (58 vs 66, P < .001). Patients with hypofibrinogenemia received more PRBC (10 vs 7 U, P = .002), FFP (9 vs 6 U, P = .003), and platelets (2 vs 1 U, P = .004) during MT. Hypofibrinogenemic patients demonstrated greater mortality than patients with normal levels (50% vs 23.5%, P = .021). Older age, decreased GCS, and elevated injury severity score (ISS) were risk factors for mortality. Increased fibrinogen was associated with lower odds of mortality (P = .001). Age, ISS, and fibrinogen level remained significantly associated with mortality in a multivariable analysis. Overall, fibrinogen in post-MT survivors showed an increase in median level compared to admission (231 vs 177.5 mg/dL, P < .001).
Conclusion: Trauma patients undergoing MT with decreased admission fibrinogen demonstrate increased mortality. Other mortality risk factors include older age, decreased GCS, and higher ISS. Patients with increased fibrinogen levels had lower odds of mortality in a multivariable model. Post-MT survivors demonstrated significantly higher fibrinogen levels than pre-MT patients. Hypofibrinogenemic patients also had worse TEG parameters and required more PRBCs, FFP, and platelets during MT. Further studies are needed to assess the optimal volume of fibrinogen replacement with cryoprecipitate during MT to improve trauma patient mortality.
Keywords: cryoprecipitate; hypofibrinogenemia; massive transfusion protocol; trauma resuscitation; traumatic hemorrhage.