A prospective evaluation of thromboelastometry (ROTEM) to identify acute traumatic coagulopathy and predict massive transfusion in military trauma patients in Afghanistan

Early Point-of-Care Thromboelastometry Reduces Mortality in Patients with Severe Trauma and Risk of Transfusion: An Analysis Based on the TraumaRegister DGU®

Background: Thromboelastometry like ROTEM® is a point-of-care method used to assess the coagulation status of patients in a rapid manner being particularly useful in critical care settings, such as trauma, where quick and accurate assessment of coagulation can guide timely and appropriate treatment. Currently, this method is not yet comprehensively available with sparse data on its effectiveness in resuscitation rooms. The aim of this study was to assess the effect of early thromboelastometry on the probability of mass transfusions and mortality of severely injured patients. Methods: The TraumaRegister DGU® was retrospectively analyzed for severely injured patients (2011 until 2020) with information available regarding blood transfusions and Trauma-Associated Severe Hemorrhage (TASH) score components. Patients with an estimated risk of mass transfusion >2% were included in a matched-pair analysis. Cases with and without use of ROTEM® diagnostic were matched based on risk categories for mass transfusion. A total of 1722 patients with ROTEM® diagnostics could be matched with a non-ROTEM® patient with an identical risk category. Adult patients (≥16) admitted to a trauma center in Germany, Austria, or Switzerland with Maximum Abbreviated Injury Scale severity ≥3 were included. Results: A total of 83,798 trauma victims were identified after applying the inclusion and exclusion criteria. For 7740 of these patients, the use of ROTEM® was documented. The mean Injury Severity Score (ISS) in patients with ROTEM® was 24.3 compared to 19.7 in the non-ROTEM® group. The number of mass transfusions showed no significant difference (14.9% ROTEM® group vs. 13.4% non-ROTEM® group, p = 0.45). Coagulation management agents were given significantly more often in the ROTEM® subgroup. Mortality in the ROTEM® group was 4.1% less than expected (estimated mortality based on RISC II 34.6% vs. observed mortality 30.5% (n = 525)). In the non-ROTEM® group, observed mortality was 1.6% less than expected. Therefore, by using ROTEM® analysis, the expected mortality could be reduced by 2.5% (number needed to treat (NNT) 40; SMR of ROTEM® group: 1:0.88; SMR of non-ROTEM® group: 1:0.96; p = 0.081). Conclusions: Hemorrhage is still one of the leading causes of death of severely injured patients in the first hours after trauma. Early thromboelastometry can lead to a more targeted coagulation management, but is not yet widely available. This study demonstrated that ROTEM® was used for the more severely injured patients and that its use was associated with a less than expected mortality as well as a higher utilization of hemostatic products.

[The chapters "Stop the bleed-prehospital" and "Coagulation management and volume therapy (emergency departement)" in the new S3 guideline "Polytrauma/severe injury treatment"]

The S3 guideline on the treatment of patients with severe/multiple injuries by the German Association of the Scientific Medical Societies was updated between 2020 and 2022. This article describes the essence of the new chapter "Stop the bleed-prehospital" and the revised chapter "Coagulation management and volume therapy".

The Addition of ROTEM Parameter Did Not Significantly Improve the Massive Transfusion Prediction in Severe Trauma Patients

Background. Rotational thrombelastometry (ROTEM) has been used to evaluate the coagulation state, predict transfusion, and optimize hemostatic management in trauma patients. However, there were limited studies on whether the prediction value could be improved by adding the ROTEM parameter to the prediction model for in-hospital mortality and massive transfusion (MT) in trauma patients. Objective. This study assessed whether ROTEM data could improve the MT prediction model. Method. This was a single-center, retrospective study. Patients who presented to the trauma center and underwent ROTEM between 2016 and 2020 were included. The primary and secondary outcomes were massive transfusions and in-hospital mortality, respectively. We constructed two models using multivariate logistic regression with backward conditional stepwise elimination (Model 1: without the ROTEM parameter and Model 2: with the ROTEM parameter). The area under the receiver operating characteristic curve (AUROC) was calculated to assess the predictive ability of the models. Result. In total, 969 patients were included; 196 (20.2%) received MT. The in-hospital mortality rate was 14.1%. For MT, the AUROC was 0.854 (95% confidence interval [CI], 0.825–0.883) and 0.860 (95% CI, 0.832–0.888) for Model 1 and 2, respectively. For in-hospital mortality, the AUROC was 0.886 (95% CI, 0.857–0.915) and 0.889 (95% CI, 0.861–0.918) for models 1 and 2, respectively. The AUROC values for models 1 and 2 were not statistically different for either MT or in-hospital mortality. Conclusion. We found that the addition of the ROTEM parameter did not significantly improve the predictive power of MT and in-hospital mortality in trauma patients.

Hemorrhagic Resuscitation Guided by Viscoelastography in Far-Forward Combat and Austere Civilian Environments: Goal-Directed Whole-Blood and Blood-Component Therapy Far from the Trauma Center

Modern approaches to resuscitation seek to bring patient interventions as close as possible to the initial trauma. In recent decades, fresh or cold-stored whole blood has gained widespread support in multiple settings as the best first agent in resuscitation after massive blood loss. However, whole blood is not a panacea, and while current guidelines promote continued resuscitation with fixed ratios of blood products, the debate about the optimal resuscitation strategy-especially in austere or challenging environments-is by no means settled. In this narrative review, we give a brief history of military resuscitation and how whole blood became the mainstay of initial resuscitation. We then outline the principles of viscoelastic hemostatic assays as well as their adoption for providing goal-directed blood-component therapy in trauma centers. After summarizing the nascent research on the strengths and limitations of viscoelastic platforms in challenging environmental conditions, we conclude with our vision of how these platforms can be deployed in far-forward combat and austere civilian environments to maximize survival.

The Role of TEG and ROTEM in Damage Control Resuscitation

ABSTRACT

Trauma-induced coagulopathy is associated with very high mortality, and hemorrhage remains the leading preventable cause of death after injury. Directed methods to combat coagulopathy and attain hemostasis are needed. The available literature regarding viscoelastic testing, including thrombelastography (TEG) and rotational thromboelastometry (ROTEM), was reviewed to provide clinically relevant guidance for emergency resuscitation. These tests predict massive transfusion and developing coagulopathy earlier than conventional coagulation testing, within 15 min using rapid testing. They can guide resuscitation after trauma, as well. TEG and ROTEM direct early transfusion of fresh frozen plasma when clinical gestalt has not activated a massive transfusion protocol. Reaction time and clotting time via these tests can also detect clinically significant levels of direct oral anticoagulants. Slowed clot kinetics suggest the need for transfusion of fibrinogen via concentrates or cryoprecipitate. Lowered clot strength can be corrected with platelets and fibrinogen. Finally, viscoelastic tests identify fibrinolysis, a finding associated with significantly increased mortality yet one that no conventional coagulation test can reliably detect. Using these parameters, guided resuscitation begins within minutes of a patient's arrival. A growing body of evidence suggests this approach may improve survival while reducing volumes of blood products transfused.

"Death Diamond" Tracing on Thromboelastography as a Marker of Poor Survival After Trauma

BACKGROUND

Improvements in health care innovations have resulted in an enhanced ability to extend patient viability. As a consequence, resources are being increasingly utilized at an unsustainable level. As we implement novel treatments, identifying futility should be a focus. The "death diamond" (DD) is a unique thrombelastography (TEG) tracing that is indicative of failure of the coagulation system, with a mortality rate exceeding 90%. The purpose of this study was to determine if the DD was a consistent marker of poor survival in a multicenter study population. We hypothesize that the DD, while an infrequent occurrence, predicts poor survival and can be used to stratify patients in whom resuscitation efforts are futile.

METHODS

A retrospective multi-institutional study of trauma patients presenting with TEG DDs between 8/2008 and 12/2018 at four American College of Surgeons trauma centers was completed. Demographics, injury mechanisms, TEG results, management, and survival were examined.

RESULTS

A total of 50 trauma patients presented with DD tracings, with a 94% (n = 47) mortality rate. Twenty-six (52%) patients received a repeat TEG with 10 patients re-demonstrating the DD tracing. There was 100% mortality in patients with serial DD tracings. The median use of total blood products was 18 units (interquartile range 6, 34.25) per patient.

DISCUSSION

The DD is highly predictive of trauma-associated mortality. This multicenter study highlights that serial DDs may represent a possible biomarker of futility.

Prevalence of Acute Traumatic Coagulopathy in Acutely Traumatized Dogs and Association with Clinical and Laboratory Parameters at Presentation

OBJECTIVE

 The aim of this study was to determine the prevalence of acute traumatic coagulopathy (ATC) and identify associated clinical and laboratory parameters including rotational thromboelastometry.

STUDY DESIGN

 Dogs presenting within 6 hours after trauma were allocated to the ATC or non-ATC group based on thromboelastometry analysis (ex-tem S, in-tem S, fib-tem S). ATC was defined as ≥2 hypocoagulable parameters in 1 profile and ≥ 1 hypocoagulable parameter in an additional profile. Parameters used were ex-tem and in-tem clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF), maximum lysis and fib-tem MCF. Clinical and laboratory parameters at presentation, animal trauma triage (ATT) score, transfusion requirement and outcome were compared. Logistic regression was used to identify independent factors associated with ATC.

RESULTS

 Eleven of 33 dogs presented with ATC and showed ex-tem CT and CFT prolongation and reduced MCF amplitude in all profiles (all p < 0.001). pH (p = 0.043) and potassium concentration (p = 0.022) were significantly lower and bleeding (p = 0.027) and plasma transfusions (p = 0.001) more common in dogs with ATC. Time after trauma (p = 0.040) and Animal Trauma Triage score (p = 0.038, including haematocrit as confounding factor) were associated with the presence of ATC.

CONCLUSION

 Acute traumatic coagulopathy is more common in traumatized dogs than previously reported. Acute traumatic coagulopathy was associated with acidosis, Animal trauma triage score, time after trauma and higher transfusion needs. Coagulation abnormalities include ex-tem CT and CFT prolongations and decreased clot strength.

"TEG talk": expanding clinical roles for thromboelastography and rotational thromboelastometry

Viscoelastic assays (VEAs) that include thromboelastography and rotational thromboelastometry add value to the investigation of coagulopathies and goal-directed management of bleeding by providing a complete picture of clot formation, strength, and lysis in whole blood that includes the contribution of platelets, fibrinogen, and coagulation factors. Conventional coagulation assays have several limitations, such as their lack of correlation with bleeding and hypercoagulability; their inability to reflect the contribution of platelets, factor XIII, and plasmin during clot formation and lysis; and their slow turnaround times. VEA-guided transfusion algorithms may reduce allogeneic blood exposure during and after cardiac surgery and in the emergency management of trauma-induced coagulopathy and hemorrhage. However, the popularity of VEAs for other indications is driven largely by extrapolation of evidence from cardiac surgery, by the drawbacks of conventional coagulation assays, and by institution-specific preferences. Robust diagnostic studies validating and standardizing diagnostic cutoffs for VEA parameters and randomized trials comparing VEA-guided algorithms with standard care on clinical outcomes are urgently needed. Lack of such studies represents the biggest barrier to defining the role and impact of VEA in clinical care.

mTICCS and its inter-rater reliability to predict the need for massive transfusion in severely injured patients

Purpose

The modified Trauma-Induced Coagulopathy Clinical Score (mTICCS) presents a new scoring system for the early detection of the need for a massive transfusion (MT). This easily applicable score was validated in a large trauma cohort and proven comparable to more established complex scoring systems. However, the inter-rater reliability of the mTICCS has not yet been investigated.

Methods

Therefore, a dataset of 15 randomly selected and severely injured patients (ISS ≥ 16) derived from the database of a level I trauma centre (2010–2015) was used. Moreover, 15 severely injured subjects that received MT were chosen from the same databank. A web-based survey was sent to medical professionals working in the field of trauma care asking them to evaluate each patient using the mTICCS.

Results

In total, 16 raters (9 residents and 7 specialists) completed the survey. Ratings from 15 medical professionals could be evaluated and led to an ICC of 0.7587 (95% Bootstrap confidence interval (BCI) 0.7149–0.8283). A comparison of working experience specific ICC (n = 7 specialists, ICC: 0.7558, BCI: 0.7076–0.8270; n = 8 residents, ICC: 0.7634, BCI: 0.7183–0.8335) showed no significant difference between the two groups (p = 0.67).

Conclusion

In summary, reliability values need to be considered when making clinical decisions based on scoring systems. Due to its easy applicability and its almost perfect inter-rater reliability, even with non-specialists, the mTICCS might therefore be a useful tool to predict the early need for MT in multiple trauma.

Viscoelastic testing in combat resuscitation: Is it time for a new standard?

BACKGROUND

Traumatic hemorrhage and coagulopathy represent major sources of morbidity and mortality on the modern battlefield. Viscoelastic testing (VET) offers a potentially more personalized approach to resuscitation. We sought to evaluate outcomes of combat trauma patients who received VET-guided resuscitation compared with standard balanced blood product resuscitation.

METHODS

Retrospective analysis of the Department of Defense Trauma Registry, 2008 to 2016 was performed. Multivariate logistic regression analyses of all adult patients initially presenting to NATO Role III facilities who required blood products were performed to identify factors associated with VET-guided resuscitation and mortality. A propensity score matched comparison of outcomes in patient cohorts treated at VET versus non-VET Role III facilities was performed.

RESULTS

There are 3,320 patients, predominately male (98%), median age ranges from 25 years to 29 years, Injury Severity Score of 18.8, with a penetrating injury (84%) were studied. Overall mortality was 9.7%. Five hundred ninety-four patients had VET during their initial resuscitation. After adjusting for confounders, VET during initial resuscitation was independently associated with decreased mortality (odds ratio, 0.63; p = 0.04). Propensity analysis confirmed this survival advantage with a 57% reduction in overall mortality (7.3% vs. 13.1%; p = 0.001) for all patients requiring blood products.

CONCLUSION

Viscoelastic testing offers the possibility of a product-specific resuscitation for critically injured patients requiring transfusion in combat settings. Routine VET may be superior to non-VET-guided resuscitation for combat trauma victims.

LEVEL OF EVIDENCE

Therapeutic study, level IV.

A prospective observational study of acute traumatic coagulopathy in traumatic bleeding from the battlefield

BACKGROUND

Acute trauma coagulopathy (ATC) after military trauma has not been comprehensively studied. ATC is defined as a prolonged prothrombin time ratio (PTr) or reduced clot amplitude (A5) in viscoelastic testing. Compared to civilian trauma, military trauma has more injuries from explosions and gunshot wounds (GSWs), potentially leading to a different pathophysiology for traumatic coagulopathy. This study aimed to characterize military ATC on admission to a military hospital in Afghanistan and to explore any differences due to the mechanism of injury.

METHODS

Severely injured military casualties were enrolled in the study. Blood samples were taken on admission and after routine testing, waste plasma was prepared, frozen, and transported to the United Kingdom for in-depth hemostatic analysis.

RESULTS

Seventy-seven percent of casualties had ATC defined by a PTr greater than 1.2 and 19% when defined by rotational thromboelastometry (ROTEM) A5 less than 36 mm. Coagulation factor depletion correlated with degree of shock, particularly factor V (p < 0.01), factor X (p < 0.01), and fibrinogen levels (p < 0.01). Thrombin generation was well preserved. Fibrinolytic biomarkers were raised correlating with the degree of shock (p < 0.01), and 8% of casualties had hyperfibrinolysis on ROTEM analysis. Plasmin-antiplasmin complexes (p < 0.01) and d-dimer levels (p = 0.01) were higher and clot firmness lower (p = 0.02) in those injured by explosion compared to GSW's.

CONCLUSIONS

ATC was present and correlated with shock, similar to civilian trauma. Thrombin generation remained adequate. Fibrinogen and factor V levels were disproportionately low but still sufficient to allow clot formation. Fibrinolysis is a key feature, probably due to a tissue plasminogen activator surge at the time of injury. Blast injuries are associated with a greater activation of fibrinolysis than GSWs.

Validation of the mTICCS Score as a Useful Tool for the Early Prediction of a Massive Transfusion in Patients with a Traumatic Hemorrhage

The modified Trauma-Induced Coagulopathy Clinical Score (mTICCS) presents a new scoring system for the early detection of the need for a massive transfusion (MT). While validated in a large trauma cohort, the comparison of mTICCS to established scoring systems is missing. This study therefore validated the ability of six scoring systems to stratify patients at risk for an MT at an early stage after trauma. A dataset of severely injured patients (ISS ≥ 16) derived from the database of a level I trauma center (2010-2015) was used. Scoring systems assessed were Trauma-Associated Severe Hemorrhage (TASH) score, Prince of Wales Hospital (PWH) score, Larson score, Assessment of Blood Consumption (ABC) score, Emergency Transfusion Score (ETS), and mTICCS. Demographics, diagnostic data, mechanism of injury, injury pattern (graded by AIS), and outcome (length of stay, mortality) were analyzed. Scores were calculated, and the area under the receiver operating characteristic curves (AUCs) were evaluated. From the AUCs, the cut-off point with the best relationship of sensitivity-to-specificity was used to recalculate sensitivity, specificity, positive predictive values (PPV), and negative predictive values (NPV). A total of 479 patients were included; of those, blunt trauma occurred in 92.3% of patients. The mean age of patients was 49 ± 22 years with a mean ISS of 25 ± 29. The overall MT rate was 8.4% (n = 40). The TASH score had the highest overall accuracy as reflected by an AUC of 0.782 followed by the mTICCS (0.776). The ETS was the most sensitive (80%), whereas the TASH score had the highest specificity (82%) and the PWH score had the lowest (51.83%). At a cut-off > 5 points, the mTICCS score showed a sensitivity of 77.5% and a specificity of 74.03%. Compared to sophisticated systems, using a higher number of weighted variables, the newly developed mTICCS presents a useful tool to predict the need for an MT in a prehospital situation. This might accelerate the diagnosis of an MT in emergency situations. However, prospective validations are needed to improve the development process and use of scoring systems in the future.

Patient Blood Management

Patient blood management is a highly successful and cost-effective concept that improves patient outcome by correction of anemia with hematinic medication and reduction of blood loss perioperatively by meticulous surgical techniques and individualized coagulation management.

Comparison of thromboelastography versus conventional coagulation tests in simulated Crotalus atrox envenomation using human blood

INTRODUCTION

Pit viper bites are a source of significant morbidity and mortality. Pit viper bites can cause venom-induced consumptive coagulopathy (VICC), typically evaluated with laboratory-based conventional coagulation tests (CCTs). However, CCTs require a laboratory and average 1 h to conduct. Thromboelastography (TEG) provides real-time, point-of-care tests of coagulation that are fast and require no separate laboratory facilities, which could be advantageous in both hospital and austere settings. However, the relative efficacy of TEG versus CCTs was unclear, particularly at low venom concentrations. Therefore, the objectives of this study were to test human blood with various concentrations of pit viper venom using CCTs and TEG to determine dose-dependent changes, lowest observed effect concentration (LOEC), and sensitivity to detecting samples out of normal diagnostic range.

METHODS

Blood samples from 20 volunteers were mixed with varying concentrations of western diamond back rattlesnake (Crotalus atrox) venom based on the mouse LD50_IV (none, 0.5%, 1%, 2%, 33%, 66%, and 100% LD50_IV). Samples were split and assessed with both CCTs including prothrombin time (PT), international normalized ratio (INR), partial thromboplastin time (PTT), fibrinogen, and D-dimer, along with TEG measures of reaction time (R), kinetic time (K), rate of clot formation (α-angle), and clot strength (MA). Data were analyzed as dose-dependent concentration-based changes in raw values and in percent of samples exceeding diagnostic thresholds using ANOVA and nonparametric statistics at the p < .05 threshold.

RESULTS

All evaluations showed significant concentration-dependent changes, and 100% of samples exceeded diagnostic thresholds at 33%LD50_IV and above, save D-dimer. At 0.5%LD50_IV, R, K, α-angle, PT, and INR were significantly different from controls, and at 1%LD50_IV, mean values exceeded diagnostic thresholds for R, K, α-angle, MA, PT, and INR, but not for PTT, D-dimer, or fibrinogen. At 2%LD50_IV, 100% of samples were out of normal range for K, α-angle, and PT_. CONCLUSION: TEG is effective in coagulopathy evaluations of in vitro simulated pit viper envenomation. At low venom concentrations, TEG performed as well or better than the majority of CCTs. These findings provide empirical evidence supporting the use of TEG to rapidly and accurately evaluate VICC.

Medical Application of Hydrogen in Hematological Diseases

Hydrogen gas has been reported to have medical efficacy since the 1880s. Still, medical researchers did not pay much attention to hydrogen gas until the 20th century. Recent research, both basic and clinical, has proven that hydrogen is an important physiological regulatory factor with antioxidative, anti-inflammatory, and antiapoptotic effects. In the past two decades, more than 1000 papers have been published on the topic, including organ ischemia-reperfusion injury, radiation injury, diabetes, atherosclerosis, hypertension, or cancer. We have previously hypothesized and proven the therapeutic effects of hydrogen gas in graft-versus-host disease following stem cell transplantation. In the current manuscript, we present the clinical advances of hydrogen gas in hematological disorders.