Proteomics of Coagulopathy Following Injury Reveals Limitations of Using Laboratory Assessment to Define Trauma-Induced Coagulopathy to Predict Massive Transfusion
Objective: Trauma-induced coagulopathy (TIC) is provoked by multiple mechanisms and is perceived to be one driver of massive transfusions (MT). Single laboratory values using prothrombin time (INR) or thrombelastography (TEG) are used to clinically define this complex process. We used a proteomics approach to test whether current definitions of TIC (INR, TEG, or clinical judgment) are sufficient to capture the majority of protein changes associated with MT. Methods: Eight level I trauma centers contributed blood samples from patients available early after injury. TIC was defined as INR >1.5 (INR-TIC), TEG maximum amplitude <50 mm (TEG-TIC), or clinical judgment (Clin-TIC) by the trauma surgeon. MT was defined as >10 units of red blood cells in 24 hours or >4 units RBC/hour during the first 4 hours. SomaLogic proteomic analysis of 1305 proteins was performed. Pathways associated with proteins dysregulated in patients with each TIC definition and MT were identified. Results: Patients (n = 211) had a mean injury severity score of 24, with a MT and mortality rate of 22% and 12%, respectively. We identified 578 SOMAscan analytes dysregulated among MT patients, of which INR-TIC, TEG-TIC, and Clin-TIC patients showed dysregulation only in 25%, 3%, and 4% of these, respectively. TIC definitions jointly failed to show changes in 73% of the protein levels associated with MT, and failed to identify 26% of patients that received a massive transfusion. INR-TIC and TEG-TIC patients showed dysregulation of proteins significantly associated with complement activity. Proteins dysregulated in Clin-TIC or massive transfusion patients were not significantly associated with any pathway. Conclusion: These data indicate there are unexplored opportunities to identify patients at risk for massive bleeding. Only a small subset of proteins that are dysregulated in patients receiving MT are statistically significantly dysregulated among patients whose TIC is defined based solely on laboratory measurements or clinical assessment.
Whole Blood for Civilian Urban Trauma Resuscitation: Historical, Present, and Future Considerations
AbstractWhole blood (WB) has been used for more than a century for far-forward combat resuscitation. Following the Iraq/Afghanistan combat, maritime, and austere environment use of WB for the resuscitation of severely hemorrhaging patients, there has been an increasing use of WB for the civilian urban resuscitation environment population. The impetus for this was not just improved outcomes in far-forward hospitals, which had different populations and different needs than the civilian urban population, but also an application of the lessons suggested by recent 1:1:1 plasma:platelets:packed red cells fixed-ratio studies for patients with massive transfusion needs. Mechanistic, logistic, and standardization concerns have been addressed and are evolving as the WB project advances. A small number of studies have been published on WB in the civilian urban trauma population. In addition, European experience with viscoelastic testing and resuscitation with fibrinogen and prothrombin complex concentrate has provided another viewpoint regarding the choice of resuscitation strategies for severely bleeding trauma patients in urban civilian environments. There are randomized controlled trials in process, which are testing the hypothesis that WB may be beneficial for the civilian urban population. Whether WB will improve mortality significantly is now a matter of intense study, and this commentary reviews the history, mechanistic foundations, and logistical aspects for the use of WB in the civilian trauma population.