Hemotherapy algorithm for the management of trauma-induced coagulopathy: the German and European perspective

Quick model-based viscoelastic clot strength predictions from blood protein concentrations for cybermedical coagulation control

Cybermedical systems that regulate patient clotting in real time with personalized blood product delivery will improve treatment outcomes. These systems will harness popular viscoelastic assays of clot strength such as thromboelastography (TEG), which help evaluate coagulation status in numerous conditions: major surgery (e.g., heart, vascular, hip fracture, and trauma); liver cirrhosis and transplants; COVID-19; ICU stays; sepsis; obstetrics; diabetes; and coagulopathies like hemophilia. But these measurements are time-consuming, and thus impractical for urgent care and automated coagulation control. Because protein concentrations in a blood sample can be measured in about five minutes, we develop personalized, phenomenological, quick, control-oriented models that predict TEG curve outputs from input blood protein concentrations, to facilitate treatment decisions based on TEG curves. Here, we accurately predict, experimentally validate, and mechanistically justify curves and parameters for common TEG assays (Functional Fibrinogen, Citrated Native, Platelet Mapping, and Rapid TEG), and verify results with trauma patient clotting data.

Systemic hemostatic agents initiated in trauma patients in the pre-hospital setting: a systematic review

Purpose

The effect of systemic hemostatic agents initiated during pre-hospital care of severely injured patients with ongoing bleeding or traumatic brain injury (TBI) remains controversial. A systematic review and meta-analysis was therefore conducted to assess the effectiveness and safety of systemic hemostatic agents as an adjunctive therapy in people with major trauma and hemorrhage or TBI in the context of developing the Italian National Institute of Health guidelines on major trauma integrated management.

Methods

PubMed, Embase, and Cochrane Library databases were searched up to October 2021 for studies that investigated pre-hospital initiated treatment with systemic hemostatic agents. The certainty of evidence was evaluated with the Grading of Recommendations Assessment, Development, and Evaluation approach, and the quality of each study was determined with the Cochrane risk-of-bias tool. The primary outcome was overall mortality, and secondary outcomes included cause-specific mortality, health-related quality of life, any adverse effects and blood product use, hemorrhage expansion, and patient-reported outcomes.

Results

Five trials of tranexamic acid (TXA) met the inclusion criteria for this meta-analysis. With a high certainty of evidence, when compared to placebo TXA reduced mortality at 24 h (relative risk = 0.83, 95% confidence interval = 0.73–0.94) and at 1 month among trauma patients (0.91, 0.85–0.97). These results depend on the subgroup of patients with significant hemorrhage because in the subgroup of TBI there are no difference between TXA and placebo. TXA also reduced bleeding death and multiple organ failure whereas no difference in health-related quality of life.

Conclusion

Balancing benefits and harms, TXA initiated in the pre-hospital setting can be used for patients experiencing major trauma with significant hemorrhage since it reduces the risk of mortality at 24 h and one month with no difference in terms of adverse effects when compared to placebo. Considering the subgroup of severe TBI, no difference in mortality rate was found at 24 h and one month. These results highlight the need to conduct future studies to investigate the role of other systemic hemostatic agents in the pre-hospital settings.

Coagulopathy management of multiple injured patients - a comprehensive literature review of the European guideline 2019

The European guideline on the management of trauma-induced major bleeding and coagulopathy summarises the most relevant recommendations for trauma coagulopathy management. The management of trauma-induced major bleeding should interdisciplinary follow algorithms which distinguish between life-threatening and non-life-threatening bleeding. Point-of-care viscoelastic methods (VEM) assist target-controlled haemostatic treatment. Neither conventional coagulation assays nor VEM should delay treatment in life-threatening trauma-induced bleeding. Adjustments may be rational due to local circumstances, including the availability of blood products, pharmaceuticals, and employees.

Dynamic use of fibrinogen under viscoelastic assessment results in reduced need for plasma and diminished overall transfusion requirements in severe trauma

BACKGROUND

Despite advances in trauma management, half of trauma deaths occur secondary to bleeding. Currently, hemostatic resuscitation strategies consist of empirical transfusion of blood products in a predefined fixed ratio (1:1:1) to both treat hemorrhagic shock and correct trauma-induced coagulopathy. At our hospital, the implementation of a resuscitation protocol guided by viscoelastic hemostatic assays (VHAs) with rotational thromboelastometry has resulted in a goal-directed approach. The objective of the study is twofold, first to analyze changes in transfusion practices overtime and second to identify the impact of these changes on coagulation parameters and clinical outcomes. We hypothesized that progressive VHA implementation results in a higher administration of fibrinogen concentrate (FC) and lower use of blood products transfusion, especially plasma.

METHODS

A total of 135 severe trauma patients (January 2008 to July 2019), all requiring and initial assessment for high risk of trauma-induced coagulopathy based on high-energy injury mechanism, severity of bleeding and hemodynamic instability were included. After 2011 when we first modified the transfusion protocol, a progressive change in transfusional management occurred over time. Three treatment groups were established, reflecting different stages in the evolution of our strategy: plasma (P, n = 28), plasma and FC (PF, n = 64) and only FC (F, n = 42).

RESULTS

There were no significant differences in baseline characteristics among groups. Progressive implementation of rotational thromboelastometry resulted in increased use of FC over time ( p < 0.001). Regression analysis showed that group F had a significant reduction in transfusion of packed red blood cells ( p = 0.005), plasma ( p < 0.001), and platelets ( p = 0.011). Regarding outcomes, F patients had less pneumonia ( p = 0.019) and multiorgan failure ( p < 0.001), without significant differences for other outcomes. Likewise, overall mortality was not significantly different. However, further analysis comparing specific mortality due only to massive hemorrhage in the F group versus all patients receiving plasma, it was significantly lower ( p = 0.037).

CONCLUSION

Implementing a VHA-based algorithm resulted in a plasma-free strategy with higher use of FC and a significant reduction of packed red blood cells transfused. In addition, we observed an improvement in outcomes without an increase in thrombotic complications.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Gestational hemostasis: a natural model for hemostasis resuscitation of major periprocedural blood loss : "Look deep into nature, and then you will understand everything better." Albert Einstein

Early goal-directed treatment is an evidence-based approach to guide hemostatic therapy during major periprocedural bleeding. If viscoelastic coagulation tests are not available, an algorithm, termed the pyramid of hemostatic interventions, can help manage severe bleeding. Pregnant women accumulate huge reserves of prothrombotic and antifibrinolytic hemostatic elements to avoid peripartum blood loss. We provide comparison of therapeutic hemostatic approaches and natural gestational process and identified remarkable analogy between early goal-directed management of bleeding and hemostatic adaptation of pregnant woman. Therefore, gestational hemostasis serves as a natural model for goal-directed hemostasis resuscitation and can foster understanding of hemostatic management of periprocedural bleeding.

Personalized modulation of coagulation factors using a thrombin dynamics model to treat trauma-induced coagulopathy

Current trauma-induced coagulopathy resuscitation protocols use slow laboratory measurements, rules-of-thumb, and clinician gestalt to administer large volumes of uncharacterized, non-tailored blood products. These one-size-fits-all treatment approaches have high mortality. Here, we provide significant evidence that trauma patient survival 24 h after hospital admission occurs if and only if blood protein coagulation factor concentrations equilibrate at a normal value, either from inadvertent plasma-based modulation or from innate compensation. This result motivates quantitatively guiding trauma patient coagulation factor levels while accounting for protein interactions. Toward such treatment, we develop a Goal-oriented Coagulation Management (GCM) algorithm, a personalized and automated ordered sequence of operations to compute and specify coagulation factor concentrations that rectify clotting. This novel GCM algorithm also integrates new control-oriented advancements that we make in this work: an improvement of a prior thrombin dynamics model that captures the coagulation process to control, a use of rapidly-measurable concentrations to help predict patient state, and an accounting of patient-specific effects and limitations when adding coagulation factors to remedy coagulopathy. Validation of the GCM algorithm's guidance shows superior performance over clinical practice in attaining normal coagulation factor concentrations and normal clotting profiles simultaneously.

Infrastructure, logistics and clinical practice management of acute trauma hemorrhage and coagulopathy: a survey across German trauma centers

PURPOSE

Early detection and management of acute trauma hemorrhage and coagulopathy have been associated with improved outcomes, but local infrastructure, logistics and clinical strategies may differ.

METHODS

To assess local differences in infrastructure, logistics and clinical management of acute trauma hemorrhage and coagulopathy we have conducted a web-based survey amongst clinicians working in DGU^®-certified supraregional, regional and local trauma centers.

RESULTS

137/1875 respondents completed the questionnaire yielding a response rate of 7.3%. The majority specified to work as head of department or senior consultant (95%) in trauma/orthopedic surgery (80%) of supraregional (38%), regional (34%) or local (27%) trauma centers. Conventional coagulation assays are most frequently used to monitor bleeding trauma patients. Only half of the respondents (53%) rely on extended coagulation tests, e.g. viscoelastic hemostatic assays. Tests to assess preinjury use of direct oral anticoagulants and platelet inhibitors are still not widely available and vary according to level of care. Conventional blood products are widely available but there remain differences between trauma centers of different level of care to access other hemostatic therapies, e.g. coagulation factor concentrates. Trauma centers of higher level of care are more likely to implement treatment protocols.

CONCLUSION

This survey confirms still existing differences in infrastructure, logistics and clinical practice management for the detection of acute trauma hemorrhage and coagulopathy amongst DGU^®-certified supraregional, regional and local trauma centers. Further work is recommended to locally implement diagnostics, therapies and treatment algorithms compliant to current guidelines to ensure the best possible outcomes in bleeding trauma patients.

Fibrinogen Diagnostics in Major Hemorrhage

Fibrinogen is one of the first factors to fall to critically low levels in the blood in many coagulopathic events. Patients with hypofibrinogenemia are at a significantly greater risk of major hemorrhage and death. The rapid replacement of fibrinogen early on in hypofibrinogenemia may significantly improve outcomes for patients. Fibrinogen is present at concentrations between 2 and 4 g/L in the plasma of healthy people. However, hypofibrinogenemia is diagnosed when the fibrinogen level drops below 1.5-2 g/L. This review analyses different types of fibrinogen assays that can be used for diagnosing hypofibrinogenemia. The scientific mechanisms and limitations behind these tests are then presented. Additionally, the current state of clinical major hemorrhage protocols (MHPs) is presented and the structure, function and physiological role of fibrinogen is summarized.

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.

Coagulation monitoring and transfusion in major non-emergency orthopaedic surgery - An observational study

Objective

Perioperative coagulation monitoring and transfusions were evaluated.

Methods

70 cases were included. Time points: before (PRE), after surgery (POST), day 1, day 3, day 7. Standard and patient near tests were assessed. Groups were: Transfused (TG); Control (CG).

Results

23 patients were transfused (TG), 47 were not (CG). PRE haemoglobin was reduced, coagulation time (CT) was prolonged in TG. FIBTEM decrease was higher in TG. Leukocytes were elevated in TG. ASPI decreased, TRAP and ADP aggregability increased in both groups.

Conclusion

CT, haemoglobin and fibrinogen were associated with transfusion. TRAP and ADP aggregability increased and could account for thromboembolism.

Damage Control Resuscitation in polytrauma patient

Haemorrhagic shock is one of the main causes of mortality in severe polytrauma patients. To increase the survival rates, a combined strategy of treatment known as Damage Control has been developed. The aims of this article are to analyse the actual concept of Damage Control Resuscitation and its three treatment levels, describe the best transfusion strategy, and approach the acute coagulopathy of the traumatic patient as an entity. The potential changes of this therapeutic strategy over the coming years are also described.

The European guideline on management of major bleeding and coagulopathy following trauma: fifth edition

Background

Severe traumatic injury continues to present challenges to healthcare systems around the world, and post-traumatic bleeding remains a leading cause of potentially preventable death among injured patients. Now in its fifth edition, this document aims to provide guidance on the management of major bleeding and coagulopathy following traumatic injury and encourages adaptation of the guiding principles described here to individual institutional circumstances and resources.

Methods

The pan-European, multidisciplinary Task Force for Advanced Bleeding Care in Trauma was founded in 2004, and the current author group included representatives of six relevant European professional societies. The group applied a structured, evidence-based consensus approach to address scientific queries that served as the basis for each recommendation and supporting rationale. Expert opinion and current clinical practice were also considered, particularly in areas in which randomised clinical trials have not or cannot be performed. Existing recommendations were re-examined and revised based on scientific evidence that has emerged since the previous edition and observed shifts in clinical practice. New recommendations were formulated to reflect current clinical concerns and areas in which new research data have been generated.

Results

Advances in our understanding of the pathophysiology of post-traumatic coagulopathy have supported improved management strategies, including evidence that early, individualised goal-directed treatment improves the outcome of severely injured patients. The overall organisation of the current guideline has been designed to reflect the clinical decision-making process along the patient pathway in an approximate temporal sequence. Recommendations are grouped behind the rationale for key decision points, which are patient- or problem-oriented rather than related to specific treatment modalities. While these recommendations provide guidance for the diagnosis and treatment of major bleeding and coagulopathy, emerging evidence supports the author group’s belief that the greatest outcome improvement can be achieved through education and the establishment of and adherence to local clinical management algorithms.

Conclusions

A multidisciplinary approach and adherence to evidence-based guidance are key to improving patient outcomes. If incorporated into local practice, these clinical practice guidelines have the potential to ensure a uniform standard of care across Europe and beyond and better outcomes for the severely bleeding trauma patient.

Electronic supplementary material

The online version of this article (10.1186/s13054-019-2347-3) contains supplementary material, which is available to authorized users.

Towards patient-specific management of trauma hemorrhage: the effect of resuscitation therapy on parameters of thromboelastometry

Essentials The response of thromboelastometry (ROTEM) parameters to therapy is unknown. We prospectively recruited hemorrhaging trauma patients in six level-1 trauma centres in Europe. Blood products and pro-coagulants prevent further derangement of ROTEM results. ROTEM algorithms can be used to treat and monitor trauma induced coagulopathy. SUMMARY: Background Rotational thromboelastometry (ROTEM) can detect trauma-induced coagulopathy (TIC) and is used in transfusion algorithms. The response of ROTEM to transfusion therapy is unknown. Objectives To determine the response of ROTEM profiles to therapy in bleeding trauma patients. Patients/Methods A prospective multicenter study in bleeding trauma patients (receiving ≥ 4 red blood cell [RBC] units) was performed. Blood was drawn in the emergency department, after administration of 4, 8 and 12 RBC units and 24 h post-injury. The response of ROTEM to plasma, platelets (PLTs), tranexamic acid (TXA) and fibrinogen products was evaluated in the whole cohort as well as in the subgroup of patients with ROTEM values indicative of TIC. Results Three hundred and nine bleeding and shocked patients were included. A mean dose of 3.8 g of fibrinogen increased FIBTEM CA5 by 5.2 mm (IQR: 4.1-6.3 mm). TXA administration decreased lysis by 5.4% (4.3-6.5%). PLT transfusion prevented further derangement of parameters of clot formation. The effect of PLTs on EXTEM ca5 values was more pronounced in patients with a ROTEM value indicative of TIC than in the whole cohort. Plasma transfusion decreased EXTEM clotting time by 3.1 s (- 10 s to 3.9 s) in the whole cohort and by 10.6 s (- 45 s to 24 s) in the subgroup of patients with a ROTEM value indicative of TIC. Conclusion The effects of therapy on ROTEM values were small, but prevented further derangement of test results. In patients with ROTEM values indicative of TIC, the efficacy of PLTs and plasma in correcting deranged ROTEM parameters is possibly more robust.

Current strategies for hemostatic control in acute trauma hemorrhage and trauma-induced coagulopathy

Introduction: Despite advances in the treatment of severely injured patients that have resulted in overall improved outcomes, uncontrolled hemorrhage still represents the most common cause of preventable death following major injury. While addressing both endo- and exogenous factors that lead to an acute trauma-induced coagulopathy, massive transfusion plays a key role in managing bleeding trauma patients. However, the best practice for hemostatic control including massive transfusion in these patients is still under debate. Areas covered: This review summarizes the current knowledge and clinical practice for hemostatic control including massive transfusion for bleeding trauma patients. The recent literature was reviewed and extended by current guidelines and their underlying evidence was incorporated. Expert commentary: Treatment strategies for bleeding trauma patients are still an area of emerging scientific and clinical interest as advances are likely to translate into improved outcomes including survival. To date, damage control resuscitation principles with ratio-based transfusion of packed red blood cells, plasma and platelets still dominate as "gold standard" of care but goal-directed strategies guided either by conventional coagulation tests or viscoelastic assays may demonstrate a better characterization of the underlying coagulopathy thereby allowing individualized and targeted therapies.

The use of fibrinogen concentrate for the management of trauma-related bleeding: a systematic review and meta-analysis

Haemorrhage following injury is associated with significant morbidity and mortality. The role of fibrinogen concentrate in trauma-induced coagulopathy has been the object of intense research in the last 10 years and has been systematically analysed in this review. A systematic search of the literature identified six retrospective studies and one prospective one, involving 1,650 trauma patients. There were no randomised trials. Meta-analysis showed that fibrinogen concentrate has no effect on overall mortality (risk ratio: 1.07, 95% confidence interval: 0.83-1.38). Although the meta-analytic pooling of the current literature evidence suggests no beneficial effect of fibrinogen concentrate in the setting of severe trauma, the quality of data retrieved was poor and the final results of ongoing randomised trials will help to further elucidate the role of fibrinogen concentrate in traumatic bleeding.

Changes in colloid solution sales in Nordic countries

BACKGROUND

Administration of resuscitation fluid is a common intervention in the treatment of critically ill patients, but the right choice of fluid is still a matter of debate. Changes in medical practice are based on new evidence and guidelines as well as traditions and personal preferences. Official warnings against the use of hydroxyl-ethyl-starch (HES) solutions have been issued. Nordic guidelines have issued several strong recommendations favouring crystalloids over colloids in all patient groups. Our objective was to describe the patterns of colloid use in Nordic countries from 2012 to 2016.

METHODS

The data were obtained from companies that provide pharmaceutical statistics in different countries. The data are sales figures from pharmaceutical companies to pharmacies and health institutions.

RESULTS

We found a 56% reduction in the total sales of all colloids in Nordic countries over a 5-year period. These findings were mainly related to a 92% reduction in the sales of HES solutions. A reduction in sales of other synthetic colloids has also occurred. During the same period, we found a 46% increase in albumin sales, but these numbers varied between Nordic countries.

CONCLUSION

The general reduction in colloid sales likely reflects the recommendation that colloids should be used only in special circumstances. The dramatic reduction in the sales of HES solutions was expected given evidence of harm and the official warnings. The steady increase in albumin sales and the notable differences between the five Nordic countries cannot be explained.