Abstract
Introduction
Plasma thrombin generation(TG) has been used to characterize trauma-induced coagulopathy, but description of whole blood(WB) TG is lacking. This study aimed to evaluate plasma and WB TG in healthy volunteers and trauma patients. We hypothesize that 1) plasma and WB TG are distinct, 2) WB TG is more pronounced in trauma patients than in healthy volunteers , and 3) TG correlates with clinical coagulation assays.
Methods
Blood was collected from healthy volunteers and trauma patients at a single, level-1 trauma center. WB TG was assessed with a prototype point-of-care WB TG device, and plasma TG was measured with a CAT analogue. Plasma and WB TG were compared and correlated with international normalized ratio(INR) and thrombelastography(TEG).
Results
Overall, 10 healthy volunteers (average age 30, 50% male) were included; 58 trauma patients(average age 34, 76% male, 55% blunt mechanism, and with a median new injury severity score (NISS) of 17 were included. Plasma and whole blood TG differed with more robust TG in plasma. Trauma patients had a significantly increased WB TG compared to healthy volunteers ]. Plasma TG correlated with INR, whereas WB TG did not correlate with TEG.
Conclusions
Plasma and whole blood TG are distinct, highlighting the need to perform standardized assays to better understand their correlation and to assess how WB TG confers differential outcomes in trauma.
Introduction
Trauma-induced coagulopathy (TIC) is one of the leading causes of preventable death in injured patients1. While TIC includes a spectrum of phenotypes from a hypocoagulable to a hypercoagulable state, it is the former, characterized by prolonged clot formation and accelerated fibrinolysis, which poses the greatest risk of early mortality after traumatic injury2. Approximately 15% of trauma patients present in this hypocoagulable profile due to a combination of shock, depletion of blood factors, platelet dysfunction, endotheliopathy, and fibrinolysis2-4. Despite this pathologic coagulation cascade, the majority of trauma patients paradoxically present with increased thrombin generation5-7. This observation has been described in plasma from severely injured patients, however, the description of whole blood thrombin generation (TG) is lacking6,7. Given that platelets are critical in initiating clot formation, characterizing TIC in whole blood assays is crucial. This need has been recognized in other hematologic pathologies such as hemophilia where point-of-care whole blood TG is being explored as a diagnostic and therapeutic tool. While the plasma-based prothrombin time/international normalized ratio (PT/INR) and whole blood thrombelastography (TEG) have been compared, differences between plasma and whole blood TG have yet to be investigated fully.
This study aimed to compare plasma and whole blood TG in healthy volunteers and trauma patients and to examine their respective correlations to conventional plasma-based and whole blood viscoelastic assays. We hypothesize that plasma and whole blood TG are distinct, and whole blood TG is more pronounced in trauma patients than healthy volunteers. Because whole blood TG and citrated rapid TEG are both measured in whole blood in the presence of exogenous tissue factor, and plasma TG and PT/INR are both measured in plasma after addition of phospholipids, we also hypothesize that plasma TG correlates to PT/INR, whereas whole blood TG correlates to TEG.
Methods
Study Design
To compare plasma and whole blood TG among healthy volunteers, blood was collected from healthy adult (≥18 years) donors recruited at Denver Health (DH). This study was approved by the Colorado Multiple Institutional Review Board (COMIRB 18-0625), and all subjects provided informed consent. We collected basic demographic data, including age, sex, and body mass index (BMI) .
For our analysis of trauma patients, we conducted an analysis of prospectively collected data from our Trauma Activation Protocol (TAP), a registry which includes all trauma activation patients from 2015 to 2017 at the Ernest E Moore Shock Trauma Center at DH, an American College of Surgeons verified and Colorado state certified academic Level-1 trauma center. The TAP study was approved by the Colorado Multiple Institution Review Board (COMIRB#13-3087) and performed under waiver of consent. Clinical data were collected by trained research professional assistants and included: age, sex, BMI, mechanism of injury, new injury severity score (NISS), field and hospital arrival systolic blood pressure (SBP), Glasgow Coma Scale (GCS), base deficit, complete blood count, PT/INR, partial thromboplastin time (PTT), number of blood products transfused, clinical outcomes, and mortality.
Participants
For our healthy volunteer recruitment, volunteers were screened via a questionnaire (Supplemental Digital Content [SDC] 1) to determine eligibility. Volunteers were excluded if they had any conditions known to affect coagulation as listed in the questionnaire.
Criteria for inclusion in TAP were adult patients (≥18 years old) who presented to the hospital as a trauma activation, an emergency department walk-in, or non-transfer patients who were upgraded to a trauma activation upon arrival. The criteria for activation were traumatic injury with any of the following: 1) GCS < 8 with presumed thoracic, abdominal, or pelvic injury, 2) respiratory compromise with presumed thoracic, abdominal, or pelvic injury, 3) blunt trauma with SBP < 90 mm Hg, 4) mechanically unstable pelvic injury, 5) penetrating injuries to the neck and/or torso with SBP < 90 mm Hg or that require endotracheal intubation, 6) amputation proximal to the ankle or wrist, or 7) the when the emergency medicine attending or the chief y resident in surgery suspected that urgent operative intervention may be required. Exclusion criteria include any patient < 18 years, patients whose initial blood sample was not collected within one hour of injury, infusion of blood products prior to collection of blood samples, consultations from external hospitals, documented chronic liver disease (total bilirubin > 2.0 mg/dL or advanced cirrhosis discovered on laparotomy), known inherited defects of coagulation function (e.g. hemophilia or Von Willebrand’s disease), subsequent downgrades from trauma activation, and patients who were pregnant or prisoners. Patients were removed from the study if any of these criteria became known after activation.
Procedures
Whole blood samples were collected in healthy volunteers and trauma activation patients at the scene by trained paramedics or on hospital presentation within one hour of injury in citrated vacuum tubes (3.5 mL, 3.2% sodium citrate) for TEG and plasma CAT and sodium citrate-corn trypsin inhibitor (CTI) vacuum tubes (3.2% sodium citrate with 100 μg/mL CTI which inhibits the contact pathway of coagulation) for whole blood TG. A team of trained research professional assistants completed whole blood TG and TEG within one and two hours of venipuncture respectively in the research lab adjacent to the Emergency Department. Citrated rapid (CR-) TEG was performed with the TEG 5000 Thrombelastography Hemostasis Analyzer (Haemonetics, Niles, IL) according to the manufacturer instructions8, and whole blood TG was performed with the prototype point-of-care WB TG device (Near Patient Testing Thrombin Generation; NPT-TG). This latter experimental point-of-care prototype was created for the evaluation of TG in WB and while not yet FDA-approved, it is currently undergoing laboratory evaluation at three trauma centers. The device functions by activating thrombin generation by relipidated tissue factor, after which point, the reaction is monitored continuously by means of a thrombin-specific, fluorogenic substrate. Change in the intensity of fluorescence produced by the cleavage of the fluorogenic substrate by thrombin is monitored over time and compared to an internal calibrator with known stable thrombin activity. Whole blood TG was initiated using 6.5 pM relipidated tissue factor reagent and 15 mM CaCl2 (Stago, (NEED THE CITY,STATE)US), and TG curves were recorded continuously for 90 min at a rate of three readings per min alongside an internal calibrator. Remaining blood after TEG and whole blood TG was spun down to platelet-poor plasma (1000 g at 4°C for 15 min, then 12600 g at 4°C for six min) for storage in −80°C until time of plasma TG with a BioTek plate reader (Calibrated Automated Thrombogram [CAT] analogue). Plasma CAT TG was initiated using 20 μM (final concentration) of artificial acidic phospholipids (prepared in-house) and 15 mM CaCl2, and TG curves were recorded continuously for 60 min at a rate of three readings per min.
CR-TEG yields the following variables: activated clotting time (ACT; time elapsed from initiation of test until onset of clot formation in seconds), angle (rate of clot strength increase in degrees), maximum amplitude (MA; maximal clot strength achieved in millimeters), and percent clot lysis 30 min after reaching MA (LY30; lysis 30 min after MA in %). The measurements for TG include lag time (min from calcium addition to 10 nM of thrombin detected), peak thrombin (the maximum thrombin concentration [in nM] during the assay), time to peak thrombin (min), maximum rate of thrombin generation (nM/min; also known as velocity index), and endogenous thrombin potential (ETP, the total thrombin which can be generated in nM.min).
Statistical Analysis
The outcomes of interest were the plasma and whole blood TG measurements: lag time, peak thrombin, time to peak thrombin, maximum rate of thrombin generation, and ETP. Plasma and whole blood TG measurements were compared for each individual healthy volunteer and trauma patient with the Wilcoxon matched paired signed rank test. Whole blood TG between healthy volunteers and trauma patients were compared with the Mann-Whitney test. Because TG provides a detailed description of the enzymatic cascade to form thrombin, we also compared the correlation of plasma TG to plasma-based PT/INR and WB TG to CR-TEG ACT and angle (TEG measurements representative of enzymatic phase of coagulation) using Pearson’s correlation. Statistical analyses were performed using R software9. Statistical significance was established at p < 0.05.
Results
Healthy Volunteers: Plasma and Whole Blood TG
Overall, 10 healthy volunteers were included in this study. Half were male and the average age was 30 years. There were significant differences between whole blood and plasma TG (Table 1). Compared to whole blood TG, plasma TG reflected a greater peak thrombin (123.5 nM vs. 82.5 nM, p=0.02), greater time to peak thrombin (13.0 min vs. 10.5 min, p=0.04), greater maximum rate (62.2 vs. 21.3 nM/min, p=0.02), and greater ETP (1801 vs. 728 nM.min, p=0.002).
Table 1. Comparison of plasma and whole blood thrombin generation measurements in healthy volunteers and trauma patients.
Numbers presented as median with 25 and 75 interquartile range.
| Plasma | Whole blood | p value | |
|---|---|---|---|
| Healthy Volunteers (n=10) | |||
| Lag time (min) | 7.0 (5.8-7.9) | 7.0 (6.0-8.0) | 0.97 |
| Peak thrombin (nM) | 123.5 (96.5-157.3) | 82.5 (75.2-91.6) | 0.02 |
| Time to peak thrombin (min) | 13.0 (11.3-15.0) | 10.5 (9.7-12.2) | 0.04 |
| Maximum rate (nM/min) | 62.2 (49.5-67.5) | 21.3 (17.8-26.1) | 0.02 |
| ETP (nM.min) | 1801 (1627-2025) | 728.4 (634-797) | 0.002 |
| Trauma Patients (n=58) | |||
| Lag time (min) | 5.4 (3.9-6.8) | 3.8 (2.6-4.9) | <0.0001 |
| Peak thrombin (nM) | 318 (234-386) | 126 (84-150) | <0.0001 |
| Time to peak thrombin (min) | 8.7 (7.3-10.3) | 6.6 (4.9-9.2) | <0.0001 |
| Maximum rate (nM/min) | 168 (122-213) | 42.6 (23-64) | <0.0001 |
| ETP (nM.min) | 2425 (2097-2726) | 823.2 (708-972) | <0.0001 |
ETP = endogenous thrombin potential
Trauma Patients: Plasma and Whole Blood TG
Overall, 58 trauma patients were included in this study (Table 2). The average age was 34 years, and the majority (76%) were male. Approximately half (55%) presented after blunt trauma, and the median NISS was 17. The median presenting SBP was 119 mm Hg (92-126 IQR), and 21% presented in shock (SBP < 90 mm Hg). Whereas only 5% of patients required massive transfusion, 44% required red blood cell transfusion in the first 24 hours. Mortality rate was 17%.
Table 2. Trauma patient population demographics, hematology and clinical outcomes.
Numbers presented as median with 25 and 75 interquartile range or raw number with percent total as appropriate.
| Demographics | |
| Age (y) | 33.5 (25.5-46.6) |
| % male | 44 (76%) |
| Injury Characteristics | |
| % blunt mechanism | 32 (55%) |
| Time from injury to arrival (min) | 27 (21-34) |
| NISS | 17 (9-34) |
| % TBI | 18 (31%) |
| Laboratory Values | |
| SBP (mm Hg) | 119 (92-136) |
| Lactate (mmol/L) | 3.5 (2.2-6.6) |
| Base deficit (meq/L) | 5.8 (3.4-10.6) |
| PT/INR | 1.1 (1.0-1.2) |
| PTT (s) | 25.8 (23.3-27.9) |
| Thrombelastography | |
| ACT (seconds) | 105 (97-121) |
| Angle (degrees) | 74.4 (67.6-77.8) |
| MA (mm) | 62.0 (57.5-65.0) |
| LY30 (%) | 1.6 (0.5-3.0) |
| Whole Blood Thrombin Generation | |
| Lag time (min) | 3.8 (2.8-4.9) |
| Peak thrombin (nM) | 86.4-146.7) |
| Time to peak thrombin (min) | 6.7 (4.9-9.1) |
| Maximum rate (nM/min) | 42.6 (22.9-61.6) |
| ETP (nM.min) | 823 (711-966) |
| Clinical Outcomes | |
| RBCs/1st 6 h (units) | 0 (0-2) |
| % massive transfusion (>10 units RBCs/1st 6 ) | 3 (5%) |
| ICU LOS (days) | 3 (0-5) |
| Ventilator days | 1 (0-3) |
| Hospital duration of stay (days) | 4 (3-13) |
| % mortality | 10 (17%) |
NISS=new injury severity score, TBI=traumatic brain injury (defined as head and neck abbreviated injury score ≥ 3), SBP=systolic blood pressure, PT/INR=prothrombin time/international normalized ratio, PTT=activated partial prothrombin time, ACT=activating clotting time, MA=maximum amplitude, LY30=fibrinolysis 30 minutes after MA, ETP=endogenous thrombin potential, RBC=red blood cells, ICU=intensive care unit,
As seen in the healthy volunteers, there were significant differences between plasma and whole blood TG measurements. Compared to whole blood, plasma lag time was greater (5.4 min vs 3.8 min), peak thrombin was greater (317.5 nM vs. 125.5 nM), time to peak thrombin was greater (8.7 min vs. 6.6 min), maximum rate was greater (168 nM/min vs. 42.6 nM/min), and ETP was greater (2425.0 vs 823.2 nM.min) (p<0.0001 for all) (Table 1).
Compared to healthy volunteer WB TG, trauma patients had a distinct WB TG profile characterized by robust thrombin generation (Table 3). Trauma patients had a lesser lag time (3.8 min versus 7.0 min, p<0.0001), greater peak thrombin (125.5 nM versus 82.5 nM, p=0.003), lesser time to peak thrombin (6.6 min versus 10.5 min, p<0.0001), greater maximum rate (42.6 nM/min versus 21.3 nM/min, p=0.006), and greater ETP (823.2 nM.min versus 728.4 nM.min, p=0.02). A small standard error across the whole TG measurements was also noted, as 0.2 min for lag time, 5.7 nM for peak thrombin, 0.3 min for time to peak thrombin, 30.2 nM.min for ETP, and 4.3 nM/min for maximum rate. When comparing the thrombin generation of trauma patients’ by mechanism, while there was a suggestion of a trend toward lesser lag time in patients with blunt mechanism (3.6 versus 4.1 min, p=0.17), there were no detectable differences. Additionally, there were no differences in WB TG by NISS or TBI, possibly due to small sample size.
Table 3. Comparison of whole blood thrombin generation in healthy volunteers and trauma patients.
Numbers presented as median with 25 and 75 interquartile range.
| Healthy Volunteers (n=10) | Trauma patients (n=58) | p value | |
|---|---|---|---|
| Lag time (min) | 7.0 (6.0-8.0) | 3.8 (2.6-4.9) | <0.001 |
| Peak thrombin (nM) | 82.5 (75.2-91.6) | 125.5 (84.4-149.9) | 0.003 |
| Time to peak thrombin (min) | 10.5 (9.7-12.2) | 6.6 (4.9-9.2) | <0.001 |
| Maximum rate (nM/min) | 21.3 (17.8-26.1) | 42.6 (22.6-63.6) | 0.006 |
| ETP (nM.min) | 728 (636-797) | 823 (708-972) | 0.02 |
ETP=endogenous thrombin potential
Plasma TG correlated moderately with plasma-based PT/INR, with lag time and time to peak thrombin correlating most strongly (r=0.6, p<0.0001 for both), such that the greater the PT/INR, the greater the lag time and time to peak thrombin (Table 4, Figure 1). Peak thrombin and ETP negatively correlated with INR (r=−0.4, p=0.004 and r=−0.5, p=0.0006 respectively), such that the greater the PT/INR, the lesser the peak thrombin and ETP. Whole blood TG measurements, however, did not correlate with CR-TEG ACT or angle (r ranged from 0.1–0.2, p>0.05).
Table 4. Correlation of plasma thrombin generation (TG) and prothrombin time/international normalized ratio (PT/INR) in trauma patients.
| Pearson’s r | p value | |
|---|---|---|
| Lag time (min) | 0.6 | <0.0001 |
| Peak thrombin (nM) | −0.4 | 0.004 |
| Time to peak thrombin (min) | 0.6 | <0.0001 |
| Maximum rate (nM/min) | −0.2 | 0.07 |
| ETP (nM.min) | −0.5 | 0.0006 |
ETP=endogenous thrombin potential
Figure 1.
Correlation between plasma thrombin generation (TG) measurements and prothrombin time/international normalized ratio.
Discussion
In this investigation, we sought to compare plasma and whole blood TG in healthy volunteers and trauma patients and to examine their respective correlations to conventional plasma-based and whole blood coagulation assays. We hypothesized that plasma and whole blood TG yield different profiles, that whole blood TG is more pronounced in trauma patients than in healthy volunteers, and that plasma TG correlates to PT/INR, whereas whole blood TG correlates to TEG. These data supported our hypotheses in that plasma and whole blood TG were distinct, with plasma TG yielding greater peak thrombin, time to peak thrombin, and ETP than whole blood. Whole blood TG was more pronounced in trauma patients compared to healthy volunteers, with a lesser lag time and time to peak thrombin and increased peak thrombin, maximum rate, and ETP. Plasma TG correlated with INR, such that the greater the INR, the greater the lag time and time to peak thrombin and the lesser the peak thrombin and ETP; in contrast, whole blood TG did not correlate with TEG ACT or angle.
Thrombin is the final end product of a complex coagulation cascade under the control of a myriad of pro- and anti-coagulant proteins and is responsible for activating platelets and converting soluble fibrinogen to insoluble fibrin clot10. As such, thrombin generation is an important measure of global hemostatic balance after severe injury. The calibrated, automated thrombogram-based technology detects thrombin generation through use of a fluorogenic substrate and an internal calibrator with known concentration of thrombin activity, allowing for measurement of change in fluorescence intensity to determine thrombin concentration in a sample11,12. Studies examining this cascade in blood from severely injured patients have examined TG in platelet-poor plasma (PPP) only5,13. While this has been informative of the protein activity in plasma after severe injury, it fails to account for the cellular contributors in whole blood which may affect thrombin generation. These data indicate that plasma and whole blood TG measurements are distinct, which can be explained by the differential methodologies of these assays (use of an acidic phospholipid additive in the plasma TG assay). Plasma TG resulted in greater ETP and peak thrombin compared to whole blood TG, likely due to the phospholipid additive supporting more robust TG. These artificial acidic phospholipids concentration in plasma CAT ultimately can lead to an even more robust TG than is observed with blood cells and platelets at their physiologic concentration. For example, only 1-2 μM PL is required to lead to TG similar to that observed with platelets at their mean physiologic concentration14. This uniquely robust TG created in the plasma CAT assay may explain why some studies of plasma TG in medical and surgical patients have found inconsistent clinical correlations6,7,15,16. Another difference in the whole blood and plasma TG assays includes the collection of blood in CTI (whole blood TG) versus citrated (plasma TG) vacutainer tubes. Vacutainer tubes with CTI were used for whole blood TG as a precaution for the prevention of the contact pathway. In the case of plasma TG, CTI is added before the TG assay is performed and thus, for both assays, citrate and CTI are present. Additionally, at 6.5 pM concentration of relipidated tissue factor, the collection of blood in citrate versus CTI tube has no effect on TG in whole blood and plasma; therefore, we expect the collection of blood in citrated versus CTI tubes does not explain the TG differences. Another difference in the plasma and whole blood TG is the concentration of proteins; however, the dilution of plasma to 67% in plasma CAT assay has a limited effect on TG because both natural procoagulant proteins and serine protease inhibitors circulating in blood are diluted. Whether the use of PL in the plasma CAT is enough to explain the lack of correlation between plasma and whole blood TG seems likely, but is unclear, and these results support future investigative work with “standardized” thrombin generation assays, where similar concentrations of phospholipids and tissue factor are added to both plasma and whole blood before TG detection and comparison.
While the results of plasma and whole blood TG reflect differential methodologies, these data provide insight into the cellular contributions to TG which can be detected in whole blood TG. The central role of platelets in hemostasis was emphasized in the cell-based model proposed by Monroe and Hoffman nearly 20 years ago17. Platelets provide a catalytic scaffolding for prothrombinase assembly, initiating thrombin generation and further contributing to thrombin formation through release of polyphosphates and factor V-rich alpha granules, resulting in a rapid acceleration of initial thrombin generation12,18. In vitro investigations have elucidated that the factor V/Va released from platelets is functionally and structurally distinct from plasma factor V/Va and serves as a more efficient protein cofactor for prothrombinase, leading to distinct pronouncement of TG after initial plasma-based enzymatic activation19. Not only do platelets play a role in thrombin formation, but in vitro work has also supported the role of red blood cells (RBCs) in supporting prothrombinase and accentuating thrombin generation20. Whole blood exhibits a lesser lag phase than platelet-rich plasma, hypothesized to be driven by RBC expression of procoagulant phospholipids on RBC membranes and factor Va-dependent factor Xa binding to RBCs21,22. These cellular-specific contributions to coagulation may explain why whole blood TG did not correlate with the enzymatic phase as detected on TEG (whereas the plasma-based TG and INR correlated well as would be expected). Ultimately, these results support further investigations into whole blood TG in trauma patients. Standardized TG assays, as mentioned previously with equivalent additive methodologies may detail a discordance between plasma and whole blood TG that could be explained by cellular contribution.
Whole blood TG was more pronounced in trauma patients compared to healthy volunteers in these described data, with a lesser lag time and time to peak thrombin and increased peak thrombin, maximum rate, and ETP in trauma patients. These findings support previous literature examining plasma thrombin generation after severe injury in animal models and human patients5-7,13. In a prospective, observational study of 406 trauma activation patients compared to 29 healthy volunteers, trauma patients had a delayed lag time but increasedpeak thrombin, decreased time to peak thrombin, and increased maximum rate. Additionally, an inability to form this robust thrombin generation after trauma was linked to poor outcomes, such that depressed plasma peak thrombin was an independent predictor of massive transfusion and in-hospital mortality (odds ratio of 4.18 and 2.78, respectively). Other investigations of trauma patients describing increased peak thrombin in trauma patients report direct correlation to injury severity, such that the greater the NISS, the greater the peak thrombin16,23,24. TG’s correlation with hypercoagulability and thrombotic morbidity has also been explored. In a prospective, case-cohort study of 454 trauma patients including 83 patients who developed venous thromboembolism (VTE), initial time to peak thrombin was an independent predictor of symptomatic VTE within 92 hours after trauma25. These aforementioned investigations introduced the concept of increased TG in trauma patients but have not included whole blood TG which remains a gap in the current literature.
Limitations of this study include differential methodology of plasma and whole blood TG which limit our ability to correlate these two assays directly. The concentration of tissue factor added to citrated rapid TEG causes such a massive thrombin burst that it may skew our ability to correlate whole blood thrombin generation with ACT and angle. Another limitation in our analysis is that we evaluated singular TG measurements instead of combinations of measurements, which in composite, may describe a hypercoagulable or hypocoagulable profile correlative to conventional hemostatic assays. Lastly, this study is limited by a small sample of trauma patients, which limits the ability to differentiate thrombin generation by descriptors of tissue injury and hemorrhagic shock or prediction of mortality . The complexity of thrombin biology will need to be investigated further in a larger-scale study of whole blood TG, as well as with expanded in vitro work looking at plasma and whole blood TG with analogous additives.
In conclusion, this study compared plasma and whole blood TG in healthy volunteers and trauma patients. These data support our hypotheses that plasma and whole blood TG are distinct, a difference which can be explained by differential methodologies but which highlights the need for expansive in vitro work to elaborate the cellular contributions to thrombin generation. Whole blood TG was more pronounced in trauma patients compared to healthy volunteers, a finding supported in previous literature on plasma TG and suggestive of unique systemic response to local injury in trauma. This study informs a novel, growing field of trauma-induced coagulopathy research on thrombin biology in the whole blood environment and highlights the need to gather additional data to further elucidate the differences between plasma and whole blood TG and how differential TG profiles may confer improved clinical outcomes.
Supplementary Material
Acknowledgements
We would like to graciously acknowledge of the University of Colorado Department of Surgery for supporting the trauma research fellows, the National Institutes of Health for the T-32 grant which makes the trauma research fellows work possible, the research assistants at Denver Health who helped to collect the data, and Denver Health for supporting ongoing data collection from patients at their site. Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health (T32 GM008315 and P50 GM049222), the National Heart, Lung and Blood Institute (TACTIC grant UM1 HL120877; SB) and Department of Defense (USAMRAA, W81XWH-12-2-0028). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or other sponsors of the project. This research was also supported with materials from Haemonetics.
FUNDING/SUPPORT: Research reported in this publication was supported by the National Institute of General Medical Sciences of the National Institutes of Health (T32 GM008315 and P50 GM049222), the National Heart, Lung and Blood Institute (TACTIC grant UM1 HL120877; SB) and Department of Defense (USAMRAA, W81XWH-12-2-0028). The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health or other sponsors of the project. This research was also supported with materials from Haemonetics
Footnotes
This study will be presented at the Annual Academic Surgical Congress on Wednesday, February 06, 2019 in Houston, Texas.
COI/DISCLOSURES: Research conducted by these investigations for this manuscript and other works is supported with materials from Haemonetics and Instrumentation Laboratories.
Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
References
- 1.Sauaia A, Moore FA, Moore EE, Moser KS, Brennan R, Read RA, et al. Epidemiology of trauma deaths: a reassessment. The Journal of Trauma. 1995;38(2):185–193. [DOI] [PubMed] [Google Scholar]
- 2.Moore HB, Moore EE, Liras IN, Wade C, Huebner BR, Burlew CC, et al. Targeting resuscitation to normalization of coagulating status: Hyper and hypocoagulability after severe injury are both associated with increased mortality. American Journal of Surgery. 2017;214(6):1041–1045. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3.Gando S, Hayakawa M. Pathophysiology of Trauma-Induced Coagulopathy and Management of Critical Bleeding Requiring Massive Transfusion. Seminars in Thrombosis and Hemostasis. 2016;42(2):155–165. [DOI] [PubMed] [Google Scholar]
- 4.Cohen MJ, Christie SA. Coagulopathy of Trauma. Critical Care Clinics. 2017;33(1):101–118. [DOI] [PubMed] [Google Scholar]
- 5.Cardenas JC, Rahbar E, Pommerening MJ, Baer LA, Matijevic N, Cotton BA, et al. Measuring thrombin generation as a tool for predicting hemostatic potential and transfusion requirements following trauma. The Journal of Trauma and Acute Care Surgery. 2014;77(6):839–845. [DOI] [PubMed] [Google Scholar]
- 6.Selby R, Geerts W, Ofosu FA, Craven S, Dewar L, Phillips A, et al. Hypercoagulability after trauma: hemostatic changes and relationship to venous thromboembolism. Thrombosis Research. 2009;124(3):281–287. [DOI] [PubMed] [Google Scholar]
- 7.Voils SA, Lemon SJ, Jordan J, Riley P, Frye R. Early thrombin formation capacity in trauma patients and association with venous thromboembolism. Thrombosis Research. 2016;147:13–15. [DOI] [PubMed] [Google Scholar]
- 8.Haemonetics. TEG 5000 System User Manual. P/N 06-510-US, Manual revision: AC. Niles, IL: Haemonetics Corporation, Haemoscope Division; 2010. [Google Scholar]
- 9.dplyr: Wickham Hadley, François Romain, Henry Lionel and Müller Kirill (2018). dplyr: A Grammar of Data Manipulation. R package version 0.7.7. https://CRAN.R-project.org/package=dplyr. [Google Scholar]
- 10.Narayanan S Multifunctional roles of thrombin. Annals of Clinical and Laboratory Science. 1999;29(4):275–280. [PubMed] [Google Scholar]
- 11.Ninivaggi M, Apitz-Castro R, Dargaud Y, de Laat B, Hemker HC, Lindhout T. Whole-blood thrombin generation monitored with a calibrated automated thrombogram-based assay. Clinical Chemistry. 2012;58(8):1252–1259. [DOI] [PubMed] [Google Scholar]
- 12.Prior SM, Mann KG, Freeman K, Butenas S. Continuous thrombin generation in whole blood: New applications for assessing activators and inhibitors of coagulation. Analytical Biochemistry. 2018;551:19–25. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13.Cardenas JC, Cap AP, Swartz MD, Huby Mdel P, Baer LA, Matijevic N, et al. Plasma Resuscitation Promotes Coagulation Homeostasis Following Shock-Induced Hypercoagulability. Shock. 2016;45(2):166–173. [DOI] [PubMed] [Google Scholar]
- 14.Butenas S, Branda RF, van't Veer C, Cawthern KM, Mann KG. Platelets and phospholipids in tissue factor-initiated thrombin generation. Thrombosis and Haemostasis. 2001; 86(2) :660–667. [PubMed] [Google Scholar]
- 15.Saliba W, Zahalka W, Goldstein L, Ron G, Elias M. Padua prediction score and thrombin generation in hospitalized medical patients. Thrombosis Research. 2014;134(4):803–806. [DOI] [PubMed] [Google Scholar]
- 16.Park MS, Xue A, Spears GM, Halling TM, Ferrara MJ, Kuntz MM, et al. Thrombin generation and procoagulant microparticle profiles after acute trauma: A prospective cohort study. The Journal of Trauma and Acute Care Surgery. 2015;79(5):726–731. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 17.Hoffman M, Monroe DM. A cell-based model of hemostasis. Thrombosis and Haemostasis. 2001;85(6):958–965. [PubMed] [Google Scholar]
- 18.Rand MD, Lock JB, van't Veer C, Gaffney DP, Mann KG. Blood clotting in minimally altered whole blood. Blood. 1996;88(9):3432–3445. [PubMed] [Google Scholar]
- 19.Gertz JM, Bouchard BA. Mechanisms Regulating Acquisition of Platelet-Derived Factor V/Va by Megakaryocytes. Journal of Cellular Biochemistry. 2015;116(10):2121–2126. [DOI] [PubMed] [Google Scholar]
- 20.Whelihan MF, Zachary V, Orfeo T, Mann KG. Prothrombin activation in blood coagulation: the erythrocyte contribution to thrombin generation. Blood. 2012;120(18):3837–3845. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 21.Whelihan MF, Mann KG. The role of the red cell membrane in thrombin generation. Thrombosis Research. 2013;131(5):377–382. [DOI] [PubMed] [Google Scholar]
- 22.Peyrou V, Lormeau JC, Herault JP, Gaich C, Pfliegger AM, Herbert JM. Contribution of erythrocytes to thrombin generation in whole blood. Thrombosis and Haemostasis. 1999;81(3):400–406. [PubMed] [Google Scholar]
- 23.Park MS, Owen BA, Ballinger BA, Sarr MG, Schiller HJ, Zietlow SP, et al. Quantification of hypercoagulable state after blunt trauma: microparticle and thrombin generation are increased relative to injury severity, while standard markers are not. Surgery. 2012;151(6):831–836. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 24.Prior SM, Cohen MJ, Conroy AS, Nelson MF, Kornblith LZ, Howard BM, et al. Correlation between factor (F)XIa, FIXa and tissue factor and trauma severity. The Journal of Trauma and Acute Care Surgery. 2017;82(6):1073–1079. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25.Park MS, Spears GM, Bailey KR, Xue A, Ferrara MJ, Headlee A, et al. Thrombin generation profiles as predictors of symptomatic venous thromboembolism after trauma: A prospective cohort study. The Journal of Trauma and Acute Care Surgery. 2017;83(3):381–387. [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.