Coagulopathy In Trauma Patients Research Articles

Control of Haemorrhage in Orthopaedic Trauma.

This paper aims to outline current practices and examine promising new advancements in the modern management of haemorrhage in orthopaedic trauma. Many prehospital and perioperative haemorrhage control strategies and techniques have been available to clinicians for multiple decades, yet our understanding and utilisation of these practices continues to be refined and optimised. There is a particular focus in this article on issues related to resuscitation and coagulation in trauma. We examine the complex mechanisms that lead to coagulopathy in trauma patients as well as the transformative effect tranexamic acid has had in limiting blood loss. We also explore some emerging technologies such as endovascular interventions and clot-stabilising dressings and devices that are likely to have a significant impact going forward.

O blood type is not associated with worse coagulopathy or outcome in exsanguinating trauma

BackgroundDespite improving understanding of trauma-induced coagulopathy (TIC), mortality and morbidity due to exsanguinating trauma remain high. Increased complications due to hemorrhage have been reported in blood group O, possibly due to reduced levels of von Willebrand factor (vWF). MethodsAn urban level 1 adult trauma center registry was retrospectively queried. Patients receiving ≥6 units of pRBC within 4 ​h of presentation were included. Patient demographics, admission labs and outcomes were obtained. Univariate and multiple logistic regression analyses were performed. Results562 patients were identified. There were no significant differences in demographics, admission labs, or outcome between different ABO groups. After adjustment, Type A patients were more likely to be hypocoagulable compared to Type O patients (p ​= ​0.014). No mortality differences were seen between ABO types in multiple regression analysis. ConclusionsNo outcome or mortality differences were seen between ABO types, therefore factors other than vWF expression should be considered to explain coagulopathy in trauma patients.

Incidence of Coagulopathy After Resuscitation at a Role 1 Facility: The Prehospital Trauma Registry Experience.

The development of acute traumatic coagulopathy is associated with increased mortality and morbidity in patients with battlefield traumatic injuries. Currently, the incidence of acute traumatic coagulopathy in the Role 1 setting is unclear. We queried the Prehospital Trauma Registry (PHTR) module of the Department of Defense Trauma Registry (DoDTR) for all encounters from inception through May 2019. The PHTR captures data on Role 1 prehospital care. Data from the PHTR was linked to the DoDTR to analyze laboratory data and patient outcomes using descriptive statistics. We defined coagulopathy as an international normalized ratio (INR) of ≥1.5 or platelet count ≤150×109/L. A total of 595 patients met the inclusion criteria; 36% (212) met our definition for coagulopathy, with 31% (185) carrying low platelet numbers, 11% (68) showing an elevated INR, and 7% (41) with both. The baseline (no coagulopathy) cohort had a mean INR of 1.10 (95% CI 1.09-1.12) versus 1.38 (95% CI 1.33-1.43) in the coagulopathic cohort. The mean platelet count was 218 (95% CI 213-223) ×109/L in the baseline cohort versus 117 (95% CI 110-125) ×109/L in the coagulopathic cohort. Our findings indicate a high incidence of coagulopathy in trauma patients. Approximately one-third of wounded patients had laboratory evidence of coagulopathy upon presentation to a forward medical care facility. Advanced diagnostic facilities are therefore needed to facilitate early diagnosis of acute traumatic coagulopathy. Blood products with a long shelf life can aid in early correction.

Severe Trauma-Induced Coagulopathy: Molecular Mechanisms Underlying Critical Illness.

Trauma remains one of the leading causes of death in adults despite the implementation of preventive measures and innovations in trauma systems. The etiology of coagulopathy in trauma patients is multifactorial and related to the kind of injury and nature of resuscitation. Trauma-induced coagulopathy (TIC) is a biochemical response involving dysregulated coagulation, altered fibrinolysis, systemic endothelial dysfunction, platelet dysfunction, and inflammatory responses due to trauma. The aim of this review is to report the pathophysiology, early diagnosis and treatment of TIC. A literature search was performed using different databases to identify relevant studies in indexed scientific journals. We reviewed the main pathophysiological mechanisms involved in the early development of TIC. Diagnostic methods have also been reported which allow early targeted therapy with pharmaceutical hemostatic agents such as TEG-based goal-directed resuscitation and fibrinolysis management. TIC is a result of a complex interaction between different pathophysiological processes. New evidence in the field of trauma immunology can, in part, help explain the intricacy of the processes that occur after trauma. However, although our knowledge of TIC has grown, improving outcomes for trauma patients, many questions still need to be answered by ongoing studies.

Injury Severity, Arrival Physiology, Coagulopathy, and Outcomes Among the Youngest Trauma Patients

BackgroundAlthough physiologic differences exist between younger and older children, pediatric trauma analyses are weighted toward older patients. Trauma-induced coagulopathy, determined by rapid thrombelastography (rTEG), is a predictor of outcome in trauma patients, but the significance of rTEG values among very young trauma patients remains unknown. Our objective was to identify the prehospital or physiologic factors, including rTEG values, that were associated with mortality in trauma patients younger than 5 y old. Materials and MethodsPatients younger than 5 y old that met the highest-level trauma activation criteria at an academic children's hospital from 2010-2016 were included. Data regarding demographics, pre-hospital management, laboratory values, injury severity, and outcome were queried. Univariate and multivariate analyses were performed comparing survivors and non-survivors. ResultsA total of 356 patients were included. 60% were male, and the median age was 3 y (IQR 1–4). Overall mortality was 13% (n = 45); brain injury (91%) and hemorrhage (9%) were the causes of death. Compared to survivors, rTEG values in nonsurvivors showed longer activated clotting time and slower speed of clot formation. Clot strength was also decreased in nonsurvivors. On stepwise regression modeling, rTEG values were not significant predictors of mortality. Admission base deficit, arrival temperature, and head injury severity were identified as independent predictors of mortality. ConclusionsWhile rTEG identified coagulopathy in trauma patients < 5 y old, it was not an independent predictor of mortality. Our findings suggest that trauma providers should pay close attention to admission base deficit, arrival temperature, and head injury severity when managing the youngest trauma patients.

Hemorrhagic Shock and Resuscitation Causes Glycocalyx Shedding and Endothelial Oxidative Stress Preferentially in the Lung and Intestinal Vasculature.

Hemorrhagic shock has recently been shown to cause shedding of a carbohydrate surface layer of endothelial cells known as the glycocalyx. This shedding of the glycocalyx is thought to be a mediator of the coagulopathy seen in trauma patients. Clinical studies have demonstrated increases in shed glycocalyx in the blood after trauma, and animal studies have measured glycocalyx disruption in blood vessels in the lung, skeletal muscle, and mesentery. However, no study has measured glycocalyx disruption across a wide range of vascular beds to quantify the primary locations of this shedding. In the present study, we used a rat model of hemorrhagic shock and resuscitation to more comprehensively assess glycocalyx disruption across a range of organs. Glycocalyx disruption was assessed by fluorescent-labeled wheat germ agglutinin or syndecan-1 antibody staining in flash frozen tissue. We found that our model did elicit glycocalyx shedding, as assessed by an increase in plasma syndecan-1 levels. In tissue sections, we found that the greatest glycocalyx disruption occurred in vessels in the lung and intestine. Shedding to a lesser extent was observed in vessels of the brain, heart, and skeletal muscle. Liver vessel glycocalyx was unaffected, and kidney vessels, including the glomerular capillaries, displayed an increase in glycocalyx. We also measured reactive oxygen species (ROS) in the endothelial cells from these organs, and found that the greatest increase in ROS occurred in the two beds with the greatest glycocalyx shedding, the lungs, and intestine. We also detected fibrin deposition in lung vessels following hemorrhage-resuscitation. We conclude that the endothelium in the lungs and intestine are particularly susceptible to the oxidative stress of hemorrhage-resuscitation, as well as the resulting glycocalyx disruption. Thus, these two vessel beds may be important drivers of coagulopathy in trauma patients.

Accelerating availability of clinically-relevant parameter estimates from thromboelastogram point-of-care device.

Modeling approaches offer a novel way to detect and predict coagulopathy in trauma patients. A dynamic model, built and tested on thromboelastogram (TEG) data, was used to generate a virtual library of over 160,000 simulated RapidTEGs. The patient-specific parameters are the initial platelet count, platelet activation rate, thrombus growth rate, and lysis rate (P(0), k1, k2, and k3, respectively). Patient data from both STAAMP (n = 182 patients) and PAMPer (n = 111 patients) clinical trials were collected. A total of 873 RapidTEGs were analyzed. One hundred sixteen TEGs indicated maximum amplitude (MA) below normal and 466 TEGs indicated lysis percent above normal. Each patient's TEG response was compared against the virtual library of TEGs to determine library trajectories having the least sum-of-squared error versus the patient TEG up to each specified evaluation time ∈ (3, 4, 5, 7.5, 10, 15, 20 minutes). Using 10 nearest-neighbor trajectories, a logistic regression was performed to predict if the patient TEG indicated MA below normal (<50 mm), lysis percent 30 minutes after MA (LY30) greater than 3%, and/or blood transfusion need using the parameters from the dynamic model. The algorithm predicts abnormal MA values using the initial 3 minutes of RapidTEG data with a median area under the curve of 0.95, and improves with more data to 0.98 by 10 minutes. Prediction of future platelet and packed red blood cell transfusion based on parameters at 4 and 5 minutes, respectively, provides equivalent predictions to the traditional TEG parameters in significantly less time. Dynamic model parameters could not predict abnormal LY30 or future fresh-frozen plasma transfusion. This analysis could be incorporated into TEG software and workflow to quickly estimate if the MA would be below or above threshold value within the initial minutes following a TEG, along with an estimate of what blood products to have on hand. Therapeutic/Care Management: Level IV.

Modern Management of Bleeding, Clotting, and Coagulopathy in Trauma Patients: What Is the Role of Viscoelastic Assays?

The purpose of this review is to briefly outline the current state of hemorrhage control and resuscitation in trauma patients with a specific focus on the role viscoelastic assays have in this complex management, to include indications for use across all phases of care in the injured patient. Viscoelastic assay use to guide blood-product resuscitation in bleeding trauma patients can reduce mortality by up to 50%. Viscoelastic assays also reduce total blood products transfused, reduce ICU length of stay, and reduce costs. There are a large number of observational and retrospective studies evaluating viscoelastic assay use in the initial trauma resuscitation, but only one randomized control trial. There is a paucity of data evaluating use of viscoelastic assays in the operating room, post-operatively, and during ICU management in trauma patients, rendering their use in these settings extrapolative/speculative based on theory and data from other surgical disciplines and settings. Both hypocoagulable and hypercoagulable states exist in trauma patients, and better indicate what therapy may be most appropriate. Further study is needed, particularly in the operating room and post-operative/ICU settings in trauma patients.

A Machine Learning-Based Model to Predict Acute Traumatic Coagulopathy in Trauma Patients Upon Emergency Hospitalization.

Acute traumatic coagulopathy (ATC) is an extremely common but silent murderer; this condition presents early after trauma and impacts approximately 30% of severely injured patients who are admitted to emergency departments (EDs). Given that conventional coagulation indicators usually require more than 1 hour after admission to yield results—a limitation that frequently prevents the ability for clinicians to make appropriate interventions during the optimal therapeutic window—it is clearly of vital importance to develop prediction models that can rapidly identify ATC; such models would also facilitate ancillary resource management and clinical decision support. Using the critical care Emergency Rescue Database and further collected data in ED, a total of 1385 patients were analyzed and cases with initial international normalized ratio (INR) values >1.5 upon admission to the ED met the defined diagnostic criteria for ATC; nontraumatic conditions with potentially disordered coagulation systems were excluded. A total of 818 individuals were collected from Emergency Rescue Database as derivation cohorts, then were split 7:3 into training and test data sets. A Pearson correlation matrix was used to initially identify likely key clinical features associated with ATC, and analysis of data distributions was undertaken prior to the selection of suitable modeling tools. Both machine learning (random forest) and traditional logistic regression were deployed for prediction modeling of ATC. After the model was built, another 587 patients were further collected in ED as validation cohorts. The ATC prediction models incorporated red blood cell count, Shock Index, base excess, lactate, diastolic blood pressure, and potential of hydrogen. Of 818 trauma patients filtered from the database, 747 (91.3%) patients did not present ATC (INR ≤ 1.5) and 71 (8.7%) patients had ATC (INR > 1.5) upon admission to the ED. Compared to the logistic regression model, the model based on the random forest algorithm showed better accuracy (94.0%, 95% confidence interval [CI]: 0.922-0.954 to 93.5%, 95% CI: 0.916-0.95), precision (93.3%, 95% CI: 0.914-0.948 to 93.1%, 95% CI: 0.912-0.946), F1 score (93.4%, 95% CI: 0.915-0.949 to 92%, 95% CI: 0.9-0.937), and recall score (94.0%, 95% CI: 0.922-0.954 to 93.5%, 95% CI: 0.916-0.95) but yielded lower area under the receiver operating characteristic curve (AU-ROC) (0.810, 95% CI: 0.673-0.918 to 0.849, 95% CI: 0.732-0.944) for predicting ATC in the trauma patients. The result is similar in the validation cohort. The values for classification accuracy, precision, F1 score, and recall score of random forest model were 0.916, 0.907, 0.901, and 0.917, while the AU-ROC was 0.830. The values for classification accuracy, precision, F1 score, and recall score of logistic regression model were 0.905, 0.887, 0.883, and 0.905, while the AU-ROC was 0.858. We developed and validated a prediction model based on objective and rapidly accessible clinical data that very confidently identify trauma patients at risk for ATC upon their arrival to the ED. Beyond highlighting the value of ED initial laboratory tests and vital signs when used in combination with data analysis and modeling, our study illustrates a practical method that should greatly facilitates both warning and guided target intervention for ATC.

Bad blood: A coagulopathy associated with trauma and massive transfusion review.

Coagulopathy in trauma patients is a known contributor to death due to hemorrhage. In fact, it seen as frequently as 35% of the time. The complexity of the coagulopathy pathway requires a deliberate and planned approach. The methods used to assess and detect if a patient is coagulopathic remain challenging, but tools have been developed to assist the practitioner to effectively manage and even quickly reverse the coagulopathy. The purpose of this review is to educate trauma and emergency medicine staff on the currently available diagnostic tools to assess coagulopathy, to provide an overview of the coagulopathy pathway, as well as provide examples of how to intervene and treat coagulopathy, including the use of crew resource management during mass transfusion protocol activations.

Computational Model for Hyperfibrinolytic Onset of Acute Traumatic Coagulopathy

The onset of acute traumatic coagulopathy in trauma patients exacerbates hemorrhaging and dramatically increases mortality. The disease is characterized by increased localized bleeding, and the mechanism for its onset is not yet known. We propose that the fibrinolytic response, specifically the release of tissue-plasminogen activator (t-PA), within vessels of different sizes leads to a variable susceptibility to local coagulopathy through hyperfibrinolysis which can explain many of the clinical observations in the early stages from severely injured coagulopathic patients. We use a partial differential equation model to examine the consequences of vessel geometry and extent of injury on fibrinolysis profiles. In addition, we simulate the efficacy of tranexamic acid treatment on coagulopathy initiated through endothelial t-PA release, and are able to reproduce the time-sensitive nature of the efficacy of this treatment as observed in clinical studies.

A systematic review on the rotational thrombelastometry (ROTEM®) values for the diagnosis of coagulopathy, prediction and guidance of blood transfusion and prediction of mortality in trauma patients.

IntroductionViscoelastic assays have been promoted as an improvement over traditional coagulation tests in the management of trauma patients. Rotational thromboelastometry (ROTEM®) has been used to diagnose coagulopathy and guide hemostatic therapy in trauma. This systematic review of clinical studies in trauma investigates the ROTEM® parameters thresholds used for the diagnosing coagulopathy, predicting and guiding transfusion and predicting mortality.MethodsSystematic literature search was performed using MEDLINE, EMBASE and Cochrane databases. We included studies without restricting year of publication, language or geographic location. Original studies reporting the thresholds of ROTEM® parameters in the diagnosis or management of coagulopathy in trauma patients were included. Data on patient demographics, measures of coagulopathy, transfusion and mortality were extracted. We reported our findings according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Quality assessment and risk of bias were performed using Newcastle Ottawa Scale (NOS) and the quality assessment of diagnostic accuracy studies (QUADAS-2) tools, respectively.ResultsA total of 13 observational studies involving 2835 adult trauma patients met the inclusion criteria. Nine studies were prospective and four were retrospective. There were no randomized controlled trials. The quality of the included studies was moderate (mean NOS 5.92, standard deviation 0.26). Using QUADAS-2, only 1 study (7.6 %) had low risk of bias in all domains, and 9 studies (69.2 %) had low risk of applicability concerns. Outcomes from 13 studies were grouped into three categories: diagnosis of coagulopathy (n = 10), prediction of massive transfusion or transfusion guidance (n = 6) and prediction of mortality (n = 6). Overall, specific ROTEM® parameters measured (clot amplitude and lysis) in the extrinsically activated test (EXTEM) and the fibrin-based extrinsically activated test (FIBTEM) were consistently associated with the diagnosis of coagulopathy, increased risk of bleeding and massive transfusion, and prediction of mortality. Presence of hyperfibrinolysis by ROTEM® was associated with increased mortality.ConclusionsMost of the evidence indicates that abnormal EXTEM and FIBTEM clot amplitude (CA5, CA10) or maximal clot firmness (MCF) diagnose coagulopathy, and predict blood transfusion and mortality. The presence of fibrinolysis (abnormal lysis index [LI30] or maximum lysis [ML]) was also associated with mortality. ROTEM® thus, may be of value in the early management of trauma patients.Electronic supplementary materialThe online version of this article (doi:10.1186/s13049-016-0308-2) contains supplementary material, which is available to authorized users.

Perioperative use of specific coagulation factors in burn patients. an international survey

Burn injury is traditionally referred to as a common triggering cause for acute coagulopathy. Even though there is extensive literature exploring coagulopathy in trauma patients, few studies have focused on management of coagulopathy in specialized burn units.

Positive blood alcohol is associated with reduced DVT in trauma

IntroductionTrauma patients exhibit a complex coagulopathy which is not fully understood and deep venous thrombosis (DVT) rates remain high. The effects of alcohol (EtOH) consumption on coagulopathy in trauma patients have not been studied. We hypothesized that acute EtOH intoxication would produce a relative hypocoagulable state as measured by thrombelastography (TEG) and would be associated with reduced DVT rates. MethodsData were prospectively collected on 213 trauma patients at a level 1 trauma centre and analyzed in a retrospective secondary analysis. Thrombelastography (TEG), standard laboratory tests and ETOH levels were performed. If the level was positive, patients were grouped as EtOH+ and all patients were screened for DVT using a standard protocol. Statistical significance was p<0.05. ResultsThe EtOH+ group was predominantly male (76%), was younger (p<0.05), had a lower BMI (p<0.05), demonstrated a lower AIS extremity score (p<0.01) and was less likely to have a blunt injury (p<0.01) than the EtOH− group. Gender, ISS and other AIS scores were not significantly different. TEG values in the alcohol group demonstrated a relative hypocoagulable state that was associated with a reduced DVT incidence, 1.4% versus 16.2%, (p<0.01). This difference was not detected with conventional assays. A multivariate logistic regression was performed, controlling for common risk factors for DVT and a positive EtOH level on admission was independently associated with reduced DVT incidence. ConclusionsAlcohol consumption is associated with a relative hypocoagulable state on TEG that is associated with a decreased DVT incidence. This difference is not detected by conventional assays.

Use of recombinant factor VIIa (rFVIIa) as pre-hospital treatment in a swine model of fluid percussion traumatic brain injury.

Context:Recombinant factor VIIa (rFVIIa) has been used as an adjunctive therapy for acute post-traumatic hemorrhage and reversal of iatrogenic coagulopathy in trauma patients in the hospital setting. However, investigations regarding its potential use in pre-hospital management of traumatic brain injury (TBI) have not been conducted extensively.Aims:In the present study, we investigated the physiology, hematology and histology effects of a single pre-hospital bolus injection of rFVIIa compared to current clinical practice of no pre-hospital intervention in a swine model of moderate fluid percussion TBI.Materials and Methods:Animals were randomized to receive either a bolus of rFVIIa (90 μg/kg) or nothing 15 minutes (T15) post-injury. Hospital arrival was simulated at T60, and animals were euthanized at experimental endpoint (T360).Results:Survival was 100% in both groups; baseline physiology parameters were similar, vital signs were comparable. Animals that received rFVIIa demonstrated less hemorrhage in subarachnoid space (P = 0.0037) and less neuronal degeneration in left hippocampus, pons, and cerebellum (P = 0.00009, P = 0.00008, and P = 0.251, respectively). Immunohistochemical staining of brain sections showed less overall loss of microtubule-associated protein 2 (MAP2) and less Flouro-Jade B positive cells in rFVIIa-treated animals.Conclusions:Early pre-hospital administration of rFVIIa in this swine TBI model reduced neuronal necrosis and intracranial hemorrhage (ICH). These results merit further investigation of this approach in pre-hospital trauma care.

Mechanisms of trauma-induced coagulopathy

The identification and management of coagulopathy is a critical component of caring for the severely injured patient. Notions of the mechanisms of coagulopathy in trauma patients have been supplanted by new insights resulting from close examination of the biochemical and cellular changes associated with acute tissue injury and hemorrhagic shock. Acute intrinsic coagulopathy arising in severely injured trauma patients is now termed trauma-induced coagulopathy (TIC) and is an emergent property of tissue injury combined with hypoperfusion. Mechanisms contributing to TIC include anticoagulation, consumption, platelet dysfunction, and hyperfibrinolysis. This review discusses current understanding of TIC mechanisms and their relative contributions to coagulopathy in the face of increasingly severe injury and highlights how they interact to produce coagulation system dysfunction.

Coagulopathy In Trauma Patients Is Accompanied By Oxidation Of a Methionine Residue In The αC Domain Of Fibrinogen and Abnormal Fibrin Polymerization

IntroductionThe concentration of clottable fibrinogen in plasma decreases rapidly after severe traumatic injury and resuscitation, a reduction associated with both greater transfusion requirements and mortality. Fibrinogen is very sensitive to oxidative modification by oxidants generated during ischemia and inflammation, including hypochlorous acid and peroxynitrite, which both can oxidize methionine to methionine sulfoxide. Here, we investigated the potential of this mechanism to contribute to the coagulopathy of trauma. MethodsWe obtained plasma, clinical data, and outcomes from a biorepository of trauma patients presenting to the Emergency Department of a local Level I trauma center. Subjects with plasma INR ≥1.3 were defined as being coagulopathic while those with INR<1.3 were used as non-coagulpathic controls. We precipitated fibrinogen from plasma with glycine and tested it for the presence of methionine sulfoxide using tandem mass spectrometry. We also tested for defects in fibrin polymerization using thrombin time, reptilase time, and fibrinogen activity/antigenic ratio and correlated these changes with the presence of methionine sulfoxide in fibrinogen. The effects of selectively oxidizing certain methionine residues on fibrinogen structure and polymerization were then simulated using molecular dynamics. ResultsTrauma patients who were coagulopathic (N=31) required more blood products in the first 24 hours of care compared to non-coagulopathic subjects (N=30) (mean PRBC: 3.9 vs. 0.5 units, p < 0.001; mean plasma transfused: 3.2 vs. 0.2 units, p < 0.001; and mean platelets transfused: 0.8 vs. 0.2 units, p=0.008) and were more likely to die (29% vs. 10% mortality, ChiSqr Likelihood Ratio p=0.056). Methionine sulfoxide was selectively increased in coagulopathic trauma patients at position 476 in the alpha C domain compared to controls [mean(SEM) 1.8(0.1)% vs. 2.5(0.1)%, p=0.003] and this low-level of oxidation was confirmed to be associated with an increasing reptilase time in vitro. Mean thrombin time (16 vs. 17.8 sec, p = 0.01) and reptilase times (18.2 vs. 23.7 sec, p<0.001) were prolonged in coagulopathic subjects and the fibrinogen activity/antigen ratio, standardized to albumin content to adjust for hemodilution, tended to be higher in coagulopathic patients (1.3 vs. 1.6, p = 0.06). Percent M476alpha oxidation was associated with increased INR (R=0.5, p=0.016), lower clottable fibrinogen concentration (R=-0.546, p=0.009), increased thrombin time (R=0.4, p=0.04), and increased reptilase time (R=0.5, p=0.01). Using multivariate regression, M476alpha oxidation remained significantly associated with reptilase time (M476alpha p=0.035) after adjusting for D-dimer concentration, fibrinogen concentration, and volume of plasma transfused at the time of measurement (whole model R2=0.77, p=0.003). When M476alpha oxidation was introduced into a human fibrinogen alpha C domain homology model, thermodynamic fluctuations were reduced, favoring a more-open configuration for beta sheet-hairpins that are hypothesized to play a role in fibrin monomer lateral aggregation by their dimerization and oligomerization via beta-hairpin swapping. ConclusionsThe level of oxidation of methionine residues in fibrinogen was increased in coagulopathic trauma patients presenting to the Emergency Department. Even at low levels, this modification was associated with altered fibrin polymerization suggesting that it may contribute mechanistically to coagulopathy by altering fibrin alpha C domain dimerization during the lateral aggregation of fibrin monomer. Disclosures:White:Stasys Medical Corp: Consultancy, Equity Ownership, Membership on an entity's Board of Directors or advisory committees, Patents & Royalties; Vidacare Corp: Honoraria; NIH: Research Funding; Coulter Foundation: Research Funding; Washington State Life Sciences Discovery Fund: Research Funding.

Base deficit as an early marker of coagulopathy in trauma

The acute coagulopathy of trauma is associated with hypoperfusion, metabolic acidosis and an increased mortality rate. Biochemical markers of hypoperfusion, namely base deficit (BD) and lactate, are commonly used to assess the degree of hypoperfusion. Early identification of hypoperfusion and acidosis using BD and lactate may help predict the development of coagulopathy in trauma patients and direct therapy. To identify whether a correlation exists between BD, lactate, injury severity, early-onset coagulopathy and mortality. A retrospective chart analysis was undertaken of patients transferred directly from scene to the level I trauma unit at Inkosi Albert Luthuli Central Hospital, Durban, South Africa, from 2007 to 2008. Patients with evidence of hypoperfusion were selected. Hypoperfusion was defined as a base deficit >-2 and coagulopathy as an International Normalized Ratio (INR) of >1.2. BD, lactate, chloride, temperature, Injury Severity Score (ISS), INR and mortality were recorded in this cohort. Student's t-test and Fisher's exact test were used for continuous and categorical variables, respectively. Correlation curves were used to determine the degree of association between the variables BD, lactate and ISS with respect to the INR. A p-value of <0.05 was considered statistically significant. Of the 28 patients, males (n=18) accounted for 64.3% of admissions. The mean age was 31 years (range 1 - 75 years, median 30 years). The mechanism of injury was penetrating trauma in 5 cases (17.9%) and blunt trauma in 23 (82.1%). The median ISS was 24 (range 4 - 59). In 16 patients (57.1%) the INR was within normal limits, but in 12 (42.9%) it was over 1.2. There was a significant correlation between BD, ISS and INR (r=0.393; p=0.019 and r=0.565, respectively; p<0.001). Lactate showed a weak and non-significant association with the INR (r=0.232; p=0.18). There were a total of 12 deaths (42.8%) in this cohort of patients with biochemical evidence of hypoperfusion. There was a significant increase in mortality in patients with evidence of hypoperfusion and an elevated INR (75.0% v. 18.7%; p=0.006). BD but not lactate correlates with the development of the coagulopathy of trauma. The ISS showed a significant correlation with coagulation disturbances, and the combination of hypoperfusion and coagulopathy was associated with a significant increase in mortality.

In-vitro comparison of free oscillation rheometry (ReoRox) and rotational thromboelastometry (ROTEM) in trauma patients upon hospital admission

Plasma-based assays do not provide accurate information on haemostatic resuscitation hence viscoelastic point-of-care haemostatic assays such as rotational thromboelastometry (ROTEM Delta, Pentapharm) are used to monitor coagulopathy in trauma patients. Free oscillation rheometry (FOR) is a new whole blood haemostatic assay that measures not only the clot-forming process but also the initial viscous phase; this could potentially be of value when assessing traumatic coagulopathy. A comparative analysis between FOR and ROTEM was therefore performed. This is a prospective observational study of 40 adult trauma patients admitted to a level 1 trauma centre. Citrated whole blood was analysed with ROTEM EXTEM and FIBTEM assays and FOR Fibscreen1 and Fibscreen2 assays. Predefined variables of ROTEM and FOR were compared using Spearman's ρ. ROTEM maximum clot function (MCF) in both EXTEM and FIBTEM correlated (P < 0.0001 for both) with FOR maximum elasticity Fibscreen1 and Fibscreen2, respectively. Interestingly, ROTEM EXTEM clotting time did not correlate with any of the FOR clot initiation parameters COT1, COT2 or COT2-1 of Fibscreen1. A correlation between ROTEM EXTEM and FIBTEM and FOR Fibscreen1 and Fibscreen2 clot formation and clot strength was found as was a significant correlation between lysis index after 60 min and ClotSR30. ROTEM EXTEM did not correlate with COT1, COT2 or COT2-1 of Fibscreen1 and this warrants further investigation.

Hyperfibrinolysis Elicited via Thromboelastography Predicts Mortality in Trauma

The acute coagulopathy of trauma has been identified as a critical determinant of outcomes. Antifibrinolytic agents have recently been demonstrated to improve outcomes. This prospective study was designed to assess coagulopathy in trauma patients using thromboelastography. Trauma patients meeting our institution's highest tier of trauma team activation criteria were prospectively enrolled during a 5-month period ending April 1, 2011. Thromboelastography was performed at admission, +1 hour, +2 hours, and +6 hours using citrated blood. Hyperfibrinolysis was defined as estimated percent lysis ≥15%. Patients were followed throughout their hospital course to collect clinical data and outcomes. One hundred and eighteen patients were enrolled (77.1% were male, 51.7% had penetrating trauma, 7.6% had systolic blood pressure <90 mmHg, 47.5% had Injury Severity Score >16, and 23.7% had Glasgow Coma Scale score ≤8). Hyperfibrinolysis was present in 13 patients (11.0%), with a mean time to detection of 13 minutes (range 2 to 60 minutes). By the 6-hour sampling, 8 (61.5%) of the hyperfibrinolytic patients had expired from hemorrhage. Survivors at this point demonstrated correction of coagulopathy, however, 12 patients (92.3%) ultimately expired (75% hemorrhage, 25% head injury). On stepwise logistic regression, hyperfibrinolysis was a strong predictor of early (24 hours) mortality (odds ratio = 25.0; 95% CI, 2.8-221.4; p = 0.004), predicting 53% of early deaths. Compared with patients without hyperfibrinolysis, patients with hyperfibrinolysis had a greater need for massive transfusion (76.9% vs 8.7%; adjusted odds ratio = 19.1; 95% CI, 3.6-101.3; p < 0.001) and had a greater early mortality (69.2% vs 1.9%; adjusted odds ratio = 55.8; 95% CI, 7.2-432.3; p < 0.001) and in-hospital mortality (92.3% vs 9.5%; adjusted odds ratio = 55.5; 95% CI, 4.8-649.7; p = 0.001). In this prospective analysis, hyperfibrinolysis on thromboelastography developed in approximately 10% of patients and was considerably more likely to require massive transfusion. Hyperfibrinolysis was a strong independent predictor of mortality. Additional evaluation of the role of thromboelastography-directed antifibrinolytic therapies is warranted.