Targeted Coagulation Management in Severe Trauma: The Controversies and the Evidence

Markers of Futile Resuscitation in Traumatic Hemorrhage: A Review of the Evidence and a Proposal for Futility Time-Outs during Massive Transfusion

The reduction in the blood supply following the 2019 coronavirus pandemic has been exacerbated by the increased use of balanced resuscitation with blood components including whole blood in urban trauma centers. This reduction of the blood supply has diminished the ability of blood banks to maintain a constant supply to meet the demands associated with periodic surges of urban trauma resuscitation. This scarcity has highlighted the need for increased vigilance through blood product stewardship, particularly among severely bleeding trauma patients (SBTPs). This stewardship can be enhanced by the identification of reliable clinical and laboratory parameters which accurately indicate when massive transfusion is futile. Consequently, there has been a recent attempt to develop scoring systems in the prehospital and emergency department settings which include clinical, laboratory, and physiologic parameters and blood products per hour transfused as predictors of futile resuscitation. Defining futility in SBTPs, however, remains unclear, and there is only nascent literature which defines those criteria which reliably predict futility in SBTPs. The purpose of this review is to provide a focused examination of the literature in order to define reliable parameters of futility in SBTPs. The knowledge of these reliable parameters of futility may help define a foundation for drawing conclusions which will provide a clear roadmap for traumatologists when confronted with SBTPs who are candidates for the declaration of futility. Therefore, we systematically reviewed the literature regarding the definition of futile resuscitation for patients with trauma-induced hemorrhagic shock, and we propose a concise roadmap for clinicians to help them use well-defined clinical, laboratory, and viscoelastic parameters which can define futility.

Fibrinogen levels in severe trauma: A preliminary comparison of Clauss Fibrinogen, ROTEM Sigma, ROTEM Delta and TEG 6s assays from the FEISTY pilot randomised clinical trial

OBJECTIVE

To describe the relationships between different methods of measuring functional fibrinogen levels in severely injured, bleeding trauma patients across multiple timepoints during hospitalisation.

METHODS

In 100 adult trauma patients enrolled in the FEISTY pilot randomised clinical trial at four tertiary trauma centres in Australia, blood samples were collected prospectively. Consistency of agreement was calculated, comparing functional fibrinogen levels measured by four methods - ROTEM® Delta and Sigma FIBTEM A5, TEG® 6s CFF MA, and gold-standard Clauss Fibrinogen.

RESULTS

Comparing the ROTEM® Delta and new-generation ROTEM® Sigma machine, consistency of agreement for FIBTEM A5, measured by calculating intraclass correlation coefficients (ICCs), was ≥0.73 across all analysed timepoints, with mean differences (Sigma minus Delta) of 0.10-3.57 mm. Corresponding values comparing the ROTEM® Sigma FIBTEM A5 and TEG® 6s CFF MA were ICC = 0.55-0.82 and ICC = 4.69-7.97 (CFF MA minus A5). Comparing ROTEM® Sigma FIBTEM A5 and Clauss Fibrinogen Analysis (CFA), among statistically significant simple linear regression models, R2 was 0.25-0.67, and comparing TEG® 6s CFF MA and CFA (CFA) 0.65-0.82, although not all differences were significant with the latter comparison. Relationships across all timepoints combined were Clauss Fibrinogen (CF) (g/L) = 0.21𝑥 + 0.004 (where 𝑥 = ROTEM® Sigma FIBTEM A5 in mm) and (g/L) = 0.16𝑥 - 0.06 (where 𝑥 = TEG® 6s CFF MA in mm).

CONCLUSIONS

The present study revealed acceptable agreement between four different assays measuring functional fibrinogen, with current- and previous-generation ROTEM® machines (Sigma, Delta) performing similarly measuring functional fibrinogen via FIBTEM assay. This suggests that haemostatic resuscitation algorithms designed for the ROTEM® Delta can be applied to the ROTEM® Sigma to guide fibrinogen replacement.

Blood Transfusion for Major Trauma in Emergency Department

Severe bleeding is the leading cause of death in patients with major trauma admitted to the emergency department. It is estimated that about 50% of deaths happen within a few minutes of the traumatic event due to massive hemorrhage; 30% of deaths are related to neurological dysfunction and typically happen within two days of trauma; and approximately 20% of patients died of multiorgan failure and sepsis within days to weeks of the traumatic event. Over the past ten years, there has been an increased understanding of the underlying mechanisms and pathophysiology associated with traumatic bleeding leading to improved management measures. Traumatic events cause significant tissue damage, with the potential for severe blood loss and the release of cytokines and hormones. They are responsible for systemic inflammation, activation of fibrinolysis pathways, and consumption of coagulation factors. As the final results of this (more complex in real life) cascade, patients can develop tissue hypoxia, acidosis, hypothermia, and severe coagulopathy, resulting in a rapid deterioration of general conditions with a high risk of mortality. Prompt and appropriate management of massive bleeding and coagulopathy in patients with trauma remains a significant challenge for emergency physicians in their daily clinical practice. Our review aims to explore literature studies providing evidence on the treatment of hemorrhage with blood support in patients with trauma admitted to the Emergency Department with a high risk of death. Advances in blood transfusion protocols, along with improvements in other resuscitation strategies, have become one of the most important issues to face and a key topic of recent clinical research in this field.

Damage Control Resuscitation in Traumatic Hemorrhage: It Is More Than Fixing the Holes and Filling the Tank

Damage control resuscitation is the foundation of hemorrhagic shock management and includes early administration of plasma, tranexamic acid, and limited crystalloid-containing products.

Utility of rotational thromboelastometry in the management of massive haemorrhage at a regional Australian hospital

BACKGROUND

Rotational thromboelastometry (ROTEM) allows targeted and individualised blood product replacement.

OBJECTIVES

The study aimed to determine the impact of ROTEM-guided transfusion on the clinical course of patients with acute massive haemorrhage in a regional Australian hospital.

METHODS/MATERIALS

A retrospective review of all patients with acute massive haemorrhage that compared the characteristics, blood product use, and clinical outcomes of patients with massive haemorrhage before and after the introduction of ROTEM-guided transfusion.

RESULTS

In per-protocol analysis, the 31/97 (32%) with ROTEM-guided transfusion used less packed red blood cells (median [interquartile range]: 6 [6-8] vs. 8 [6-12] units, p = 0.03) than patients whose transfusion was not ROTEM-guided. They were also less likely to receive fresh frozen plasma (2/31 [6%] vs. 45/66 [68%], p < 0.0001) or platelets (2/31 [6%] vs. 31/66 [47%], p < 0.0001); they were, however, more likely to receive fibrinogen products (26/31 [84%] vs. 38/66 [58%], p = 0.01). Patients receiving ROTEM-guided transfusion had lower in-hospital mortality (6/31 [19%] vs. 20/66 [30%], odds ratio 0.55 [95% confidence interval]: 0.20-1.55, p = 0.26) although this did not achieve statistical significance in this small cohort.

CONCLUSION

ROTEM-guided massive transfusion of patients with acute haemorrhage in this regional Australian hospital led to a reduction in packed red blood cell, fresh frozen plasma, and platelet utilisation and may also have reduced mortality.

Raising the bar on fibrinogen: a retrospective assessment of critical hypofibrinogenemia in severely injured trauma patients

Objectives

Fibrinogen depletion may occur at higher levels than historically referenced. We evaluated hypofibrinogenemia and associated mortality and multiple organ failure (MOF) after severe injury.

Methods

Retrospective investigation including 417 adult patients with Injury Severity Score (ISS) >15. Demographics and injury characteristics were collected. Fibrinogen within 30 minutes of admission was described: <150 mg/dL, 150 mg/dL to 200 mg/dL and >200 mg/dL. Primary outcome: 28-day mortality. Secondary outcomes: 28-day MOF and blood product transfusion. Multivariable logistic regression model evaluated association of fibrinogen categories on risk of death, after controlling for confounding variables. Results presented as OR and 95% CIs.

Results

Fibrinogen <150 mg/dL: 4.8%, 150 mg/dL to 200 mg/dL: 18.2%, >200 mg/dL: 77.0%. 28-day mortality: 15.6%. Patients with <150 mg/dL fibrinogen had over fourfold increased 28-day mortality risk (OR: 4.9, 95% CI 1.53 to 15.7) after adjusting for age, ISS and admission Glasgow Coma Scale. Patients with lower fibrinogen were more likely to develop MOF (p=0.04) and receive larger red blood cell transfusion volumes at 3 hours and 24 hours (p<0.01).

Conclusions

Fibrinogen <150 mg/dL is significantly associated with increased 28-day mortality. Patients with fibrinogen <150 mg/dL were more likely to develop MOF and required increased administration of blood products. The optimal threshold for critically low fibrinogen, the association with MOF and subsequent fibrinogen replacement requires further investigation.

Level of evidence

Level III.

Clinical significance of R-TEG in severe burn patients with coagulation dysfunction

INTRODUCTION

The aim of this study was to retrospectively analyze Thrombelastography (TEG) data of severe burn patients to provide a clinical basis for timely diagnosis and treatment of coagulation dysfunction.

METHODS

The present study comprised burn patients with full thickness TBSA ≥ 60%. The patients included in the study were admitted to the Third Affiliated Hospital of Inner Mongolia Medical University between March 2019 and March 2022 and died within 10 days. Patient demographic and clinical data, including abbreviated burn severity index (ABSI) score, full thickness and overall total surface burn area (TBSA), injury cause, International Society on Thrombosis and Hemostasis (ISTH) score, were retrieved from the electronic medical record system. TEG data (including ACT, K, α, MA and LY30), platelet count (PLT), mean platelet volume (MPV) and platelet distribution width (PDW) data were obtained from the records of included patients for analysis.

RESULTS

A total of 9 patients were enrolled. The average burn area was 90.0% TBSA and the full-thickness TBSA was 72.0%. The results showed that α, MA and PLT count values were significantly lower relative to those at obtained throughout admission period (all p < 0.05). PDW and MPV were significantly higher compared with the values at admission (all p < 0.05). ACT time was significantly longer from day 2 after severe burn compared with the ACT time at admission (all p < 0.05). LY30 value from day 3 after severe burn was significantly higher compared with the value at admission (p < 0.05). One patient was diagnosed with diffuse intravascular coagulation (DIC) on admission, whereas eight patients were diagnosed with DIC on the day of death.

CONCLUSION

Coagulation dysfunction after severe burn is mainly characterized by procoagulant disorders and hyperfibrinolysis, which can be timely detected by TEG. Coagulation after severe burn exhibits a gradual aggravation, and can lead to death of patients.

Physicians' perceptions of two ways of algorithm presentation: graphic versus text-based approach

Acute bleeding during surgery or after trauma harms patients, and challenges involved physicians. Protocols and cognitive aids can help in such situations. This dual-centre study investigated physicians' opinions regarding two ways to present cognitive aids, graphic 'Haemostasis Traffic Light' and text-based, using the example of a coagulation management algorithm to identify the strengths and limitations of both presentation modalities. Using qualitative research methods, we identified recurring answer patterns and derived major topics and subthemes through inductive coding. Eighty-four physicians participated. We assigned each half randomly to one of the cognitive aids (graphic/text-based) and determined 447 usable statements. We qualitatively deduced the importance of having a cognitive aid for physicians. Furthermore, it is noticeable that the graphic group made more positive comments (154 of 242 (64%) statements), while the text-based participants made more negative annotations (126 of 205 (61%) statements), suggesting a generally stronger approval of this cognitive aid. Practitioner summary: This qualitative study provides an overview of physicians` positive and negative perceptions regarding two presentation ways for a coagulation management algorithm. Participants perceived the graphic method created according to user-centred design principles more positively. The analysis reveals components that an ideal algorithm should have to help streamline the decision-making process.

Coagulation dysfunction of severe burn patients: A potential cause of death

BACKGROUND

Research on coagulation dysfunction following burns is controversial. This study aimed to describe the coagulation changes in severe burn patients by examining coagulation parameters.

METHODS

Patients with third-degree total body surface area (TBSA) burns of ≥30% were enrolled between 2017 and 2020. Platelet (PLT) count and coagulation indexes (including APTT, INR, FIB, DD, and AT Ⅲ) were measured at admission and once weekly for 8 weeks, and statistical analysis was performed. The patient medical profiles were reviewed to extract demographic and clinical data, including TBSA, third-degree TBSA, and inhalation injury. The total intravenous fluids and transfusions of crystalloids, fresh frozen plasma (FFP), and red blood cells (RBC) were calculated during the forty-eight-hour period. The number of sepsis cases was recorded.

RESULTS

We enrolled 104 patients , and while the overall coagulation trend fluctuated, inflection points appeared around one week and demonstrated hypercoagulability. INR was significantly higher in the non-survival group than in the survivors' group from admission to three weeks after burn (all p<0.01). From post-injury week 1 to post-injury week 3, the APTT in the non-survival group was greater than in the survival group, but the non-survival group's PLT count was lower than that in the survival group (all p<0.05). At two and three weeks after burns, the FIB levels in the non-survival group were significantly lower than those of the survival group (both p<0.01). The prevalence of inhalation injury and the proportion of sepsis cases were significantly higher in the non-survival group than in the survival group ( p ＜ 0.05, p ＜ 0.001, respectively). At the time of death, APTT, INR, and FDP levels were significantly higher in the non-survival group in the survivor group, and FIB, ATIII, and PLT were significantly lower than in the survivor group (all p<0.01). On the day of death, nine of the 12 dead patients had disseminated intravascular coagulation (DIC).

CONCLUSIONS

Coagulation dysfunction was most prominent in severe burn patients 1 week after injury and presented as hypercoagulability. Large-area burn injury, large amounts of fluid resuscitation, inhalation injury, and sepsis may all contribute to coagulation dysfunction, which can further develop into DIC and even death in severe burns patients.

Correlation of Dengue Warning Signs during Febrile Phase with Rotational Thromboelastometry, Cortisol and Feritin

Dengue mortality remains high despite monitoring against warning signs (WS). The associations of WS at febrile phase (FP) and hemorrhage at defervescence with the levels and kinetics of ROTEM, platelet count, cortisol, and ferritin were analyzed. Patients with confirmed dengue serology and WS in two centers were screened (n = 275) and 62 eligible patients were recruited prospectively over 9 months. “Vomiting” was the commonest WS (62.9%), with shortened clotting time (CT) INTEM (p = 0.01). “Hematocrit increase” showed significant prolonged CT INTEM, EXTEM, and FIBTEM (p < 0.05). “Platelet decrease” showed reduced platelet function and reduced clot amplitude at 10 min (A10) and maximum clot firmness (MCF) in INTEM and EXTEM (p < 0.001). The kinetics were reduced in platelet count, CT EXTEM, and cortisol (p < 0.05) but increased in CT INTEM (p = 0.03). At FP, “vomiting”, “hematocrit increase”, and “platelet decrease” demonstrated impaired CT, clot strengths A10/MCF and platelet functions. Majority (60/62, 96.7%) had non-severe outcomes, consistent with increase in cortisol kinetics. In conclusion, “vomiting”, “hematocrit increase” and “platelet decrease” at FP correlated with ROTEM. No conclusion could be made further regarding ferritin and cortisol. Larger study is required to study “hematocrit increase” with ROTEM as a potential marker for hemorrhage.

Trauma-induced coagulopathy: Mechanisms and clinical management

INTRODUCTION

Trauma-induced coagulopathy (TIC) is a form of coagulopathy unique to trauma patients and is associated with increased mortality. The complexity and incomplete understanding of TIC have resulted in controversies regarding optimum management. This review aims to summarise the pathophysiology of TIC and appraise established and emerging advances in the management of TIC.

METHODS

This narrative review is based on a literature search (MEDLINE database) completed in October 2020. Search terms used were "trauma induced coagulopathy", "coagulopathy of trauma", "trauma induced coagulopathy pathophysiology", "massive transfusion trauma induced coagulopathy", "viscoelastic assay trauma induced coagulopathy", "goal directed trauma induced coagulopathy and "fibrinogen trauma induced coagulopathy'.

RESULTS

TIC is not a uniform phenotype but a spectrum ranging from thrombotic to bleeding phenotypes. Evidence for the management of TIC with tranexamic acid, massive transfusion protocols, viscoelastic haemostatic assays (VHAs), and coagulation factor and fibrinogen concentrates were evaluated. Although most trauma centres utilise fixed-ratio massive transfusion protocols, the "ideal" transfusion ratio of blood to blood products is still debated. While more centres are using VHAs to guide blood product replacement, there is no agreed VHA-based transfusion strategy. The use of VHA to quantify the functional contributions of individual components of coagulation may permit targeted treatment of TIC but remains controversial.

CONCLUSION

A greater understanding of TIC, advances in point-of-care coagulation testing, and availability of coagulation factors and fibrinogen concentrates allows clinicians to employ a more goal-directed approach. Still, hospitals need to tailor their approaches according to available resources, provide training and establish local guidelines.

Getting hit by the bus around the world - a global perspective on goal directed treatment of massive hemorrhage in trauma

PURPOSE OF REVIEW

Major trauma remains one of the leading causes of death worldwide with traumatic brain injury and uncontrolled traumatic bleeding as the main determinants of fatal outcome. Interestingly, the therapeutic approach to trauma-associated bleeding and coagulopathy shows differences between geographic regions, that are reflected in different guidelines and protocols.

RECENT FINDINGS

This article summarizes main principles in coagulation diagnostics and compares different strategies for treatment of massive hemorrhage after trauma in different regions of the world. How would a bleeding trauma patient be managed if they got hit by the bus in the United States, United Kingdom, Germany, Switzerland, Austria, Denmark, Australia, or in Japan?

SUMMARY

There are multiple coexistent treatment standards for trauma-induced coagulopathy in different countries and different trauma centers. Most of them initially follow a protocol-based approach and subsequently focus on predefined clinical and laboratory targets.

Implementation of point-of-care ROTEM® into a trauma major haemorrhage protocol: A before and after study

OBJECTIVE

The aim of the present study was to assess transfusion practices with the implementation of a targeted viscoelastic haemostatic assay (VHA) (ROTEM®) guided coagulation management programme into a major haemorrhage protocol for trauma patients requiring ICU admission, starting from time of arrival in the ED.

METHODS

This retrospective observational study was conducted in a major trauma centre in Australia. One hundred and sixty-two trauma patients admitted to the ICU between January 2013 and December 2015 with an Injury Severity Score ≥12 and who received blood products were included: 37 in the pre-group, 48 during implementation and 77 in post-group. The primary outcome was blood and blood product administration amounts.

RESULTS

Packed red blood cell transfusion amounts did not significantly change post introduction of the ROTEM®. There was a significant increase in fibrinogen replacement between the pre- and post-groups (P < 0.001), accompanied by a reduction in the use of fresh frozen plasma (P < 0.001) and prothrombinex (P < 0.001). Platelet usage in the post-group was higher but not reaching statistical significance (P  = 0.051). Post-implementation point-of-care ROTEM® testing was able to be performed in the ED in 94.8% of cases.

CONCLUSION

Although there was no overall reduction of packed red blood cell usage, a change in the pattern of administration of other blood products was observed with the implementation of a targeted VHA (ROTEM®) guided coagulation management programme. Larger studies are needed to further define the role of early VHA testing to guide correction of trauma-induced coagulopathy and the effect on clinical outcomes.

Role of POC INR in the early stage of diagnosis of coagulopathy

Background

Acute bleeding requires fast and targeted therapy. Therefore, knowledge of the patient's potential to form a clot is crucial. Point-of-care testing (POCT) provides fast and reliable information on coagulation. Structural circumstances, such as person-bound sample transport, can prolong the reporting of the results. The aim of the present study was to investigate the diagnostic quality and accuracy between POCT INR diagnostics and standard laboratory analysis (SLA) as well as the time advantage between a pneumatic tube and a personal-based transport system.

Methods

Two groups of haemorrhagic patients (EG: emergency department; OG: delivery room; each n = 12) were examined in the context of bleeding emergencies using POCT and SLA. Samples were transported via a pneumatic tube system or by a personal transport service.

Results

INR results between POCT and SLA showed a high and significant correlation (EG: p < 0.001; OG: p < 0.001). POCT results were reported significantly more quickly (EG: 1.1 vs. 39.6 min; OG: 2.0 vs. 75.0 min; p < 0.001) and required less time for analysis (EG: 0.3 vs. 24.0 min; OG: 0.5 vs. 45.0 min; p < 0.001) compared to SLA. The time for transportation with the pneumatic tube was significantly shorter (8.0 vs. 18.5 min; p < 0.001) than with the personal-based transport system.

Conclusion

The results of the present study suggest that POCT may be a suitable method for the emergency diagnosis and may be used as prognostic diagnostic elements in haemotherapy algorithms to initiate targeted haemotherapy at an early point in time.

Changes in emergency department blood product use for major paediatric trauma following the implementation of a major haemorrhage protocol

OBJECTIVE

Fixed ratio blood product administration may improve outcomes in trauma patients with massive blood loss. The present study aimed to describe the impact of a major haemorrhage protocol (MHP) on the ratio of blood products administered for paediatric major trauma.

METHODS

Retrospective observational study in a state-designated paediatric major trauma centre in Melbourne, Australia. Children with major trauma who received blood products in the ED were identified from a hospital trauma registry. Blood product ratios before, during and after implementation of a hospital MHP were compared in consecutive 2 year blocks.

RESULTS

Over a 6 year period, 767 major trauma patients were identified, of whom 47 received blood products in the ED and were included in the analysis; 14 pre-MHP implementation, 24 during-MHP implementation and nine post-MHP implementation. No patients received blood products at a ratio of 1:1:1 for red blood cells:fresh frozen plasma:platelets, respectively, during any time period. In this cohort of predominantly blunt trauma, blood products were infrequently administered in the ED because of the low prevalence of massive blood loss. Coagulopathy and hypofibrinogenaemia were commonly observed, nearly half of included patients were managed operatively and one quarter did not survive their injuries.

CONCLUSION

The implementation of a MHP did not change the ratio of blood product administration in this cohort of patients because of the infrequency of massive blood loss. Future studies may focus on the impact of treating coagulopathy and hypofibrinogenaemia on patient-centred outcomes.

Glycocalyx components affect platelet function, whole blood coagulation, and fibrinolysis: an in vitro study suggesting a link to trauma-induced coagulopathy

BACKGROUND

The mechanisms of trauma induced coagulopathy (TIC) are considered multifactorial. Amongst others, however, shedding of the endothelial glycocalyx resulting in increased concentrations of glycocalyx fragments in plasma might also play a role. Thus, we hypothesized that shedded glycocalyx components affect coagulation and may act as humoral mediators of TIC.

METHODS

To investigate effects of heparan sulfate, chondroitin sulfate, syndecan-1, versican, and thrombomodulin we added these fragments to in vitro assays of whole blood from healthy volunteers to yield concentrations observed in trauma patients. Platelet function, whole blood coagulation, and fibrinolysis were measured by standard coagulation tests, impedance aggregometry (IA), and viscoelastic tests (VET). To assess dose-response relationships, we performed IA with increasing concentrations of versican and VET with increasing concentrations of thrombomodulin.

RESULTS

Intrinsically activated clotting times (i.e., activated partial thromboplastin time and intrinsically activated VET with and without heparinase) were unaffected by any glycocalyx fragment. Thrombomodulin, however, significantly and dose-dependently diminished fibrinolysis as assessed by VET with exogenously added rt-PA, and increased rt-PA-induced lysis Indices after 30 (up to 108% of control, p <  0,0001), 45 (up to 368% of control, p <  0,0001), and 60 min (up to 950% of control, p <  0,0001) in VET. Versican impaired platelet aggregation in response to arachidonic acid (up to - 37,6%, p <  0,0001), ADP (up to - 14,5%, p <  0,0001), and collagen (up to - 31,8%, p <  0,0001) in a dose-dependent manner, but did not affect TRAP-6 induced platelet aggregation. Clotting time in extrinsically activated VET was shortened by heparan sulfate (- 7,2%, p = 0,024), chondroitin sulfate (- 11,6%, p = 0,016), versican (- 13%, p = 0,012%), and when combined (- 7,2%, p = 0,007).

CONCLUSIONS

Glycocalyx components exert distinct inhibitory effects on platelet function, coagulation, and fibrinolysis. These data do not support a 'heparin-like auto-anticoagulation' by shed glycosaminoglycans but suggest a possible role of versican in trauma-induced thrombocytopathy and of thrombomodulin in trauma-associated impairment of endogenous fibrinolysis.

Fibrinogen Early In Severe Trauma studY (FEISTY): results from an Australian multicentre randomised controlled pilot trial

Background: Haemorrhage is a major cause of death in severe trauma. Fibrinogen plays a critical role in maintaining haemostasis in traumatic haemorrhage, and early replacement using fibrinogen concentrate (FC) or cryoprecipitate (Cryo) is recommended by several international trauma guidelines. Limited evidence supports one product over the other, with widespread geographic and institutional variation in practice. Two previous trials have investigated the feasibility of rapid FC administration in severely injured trauma patients, with conflicting results. Objective: To compare the time to fibrinogen replacement using FC or Cryo in severely injured trauma patients with major haemorrhage and hypofibrinogenaemia. Design, setting, patients and interventions: A multicentre controlled pilot trial in which adult trauma patients with haemorrhage were randomly assigned (1:1) to receive FC or Cryo for fibrinogen replacement, guided by FIBTEM A5 (functional fibrinogen assessment at 5 minutes after clot formation, using rotational thromboelastometry). Main outcome measures: The primary outcome was time to commencement of fibrinogen replacement. Secondary outcomes included effects of the intervention on plasma fibrinogen levels and clinical outcomes including transfusion requirements and mortality. Results: Of the 100 randomly assigned patients, 62 were hypofibrinogenaemic and received the intervention (n = 37) or Cryo (n = 25). Median (interquartile range [IQR]) time to delivery of FC was 29 min (23-40 min) compared with 60 min (40-80 min) for Cryo (P = 0.0001). All 62 patients were hypofibrinogenaemic before receiving FC or Cryo (FC: median FIBTEM A5, 8 mm [IQR, 7-9 mm]; Cryo: median FIBTEM A5, 9 mm [IQR, 5-10 mm]). In the FC arm patients received a median of 3 g FC (IQR, 2-4 g), and in the Cryo arm patients received a median of 8 units of Cryo (IQR, 8-14 units). Restoration of fibrinogen levels was achieved in both arms after the intervention. Blood product transfusion, fluid resuscitation and thromboembolic complications were similar in both arms. Overall mortality was 15.3%, with more deaths in the FC arm. Conclusion: Fibrinogen replacement in severely injured trauma patients with major haemorrhage and hypofibrinogenaemia was achieved substantially faster using FC compared with Cryo. Fibrinogen levels increased appropriately using either product. The optimal method for replacing fibrinogen in traumatic haemorrhage is controversial. Our results will inform the design of a larger trial powered to assess patient-centred outcomes.

Physicians' perceptions regarding acute bleeding management: an international mixed qualitative quantitative study

Background

Acute bleeding is an omnipresent challenge for all physicians. Uncontrolled hemorrhage is the most common preventable cause of death after trauma worldwide. In different surgical disciplines, hemorrhage represents an independent risk factor for increased postoperative morbimortality, directly affecting patients’ outcomes. This study asked anesthesiologists about their personal perceived challenges when treating bleeding patients.

Methods

This investigator-initiated, prospective, international, dual-center, mixed qualitative and quantitative study interrogated anesthesiologists about what they found easy and what difficult in treating acutely bleeding patients. Following the template approach for qualitative research, we identified major and minor topics through free inductive coding and word count. In a second step, we derived ten statements from the participants’ answers. Using a field survey, we then asked the participants to rate their level of agreement with the derived statements. We analyzed the answers using one sample Wilcoxon test and the Mann-Whitney test.

Results

We included a total of 84 physicians in the qualitative interrogations and a different group of 42 anesthesiologists in the quantitative part. We identified 11 major topics and 19 associated subtopics. The main topics and the degree of agreement (here as agree or strongly agree) were as follows: “Complexity of the topic” (52.4% agreed to find the topic complex), “Cognitive aids” (92.9% agreed to find them helpful), “Time management” (64.3% agreed to feeling time pressure), “Human factors” (95.2% agreed that human factors are essential), “Resources” (95.2% agreed that resources are essential), “Experience” and “Low frequency of cases” (57.1% agreed to lack practice), “Diagnostic methods” (31.0% agreed that the interpretation of test results is difficult), “Anticoagulation” (85.7% agreed to it being difficult), “Treatment” (81.0% agreed to knowing the first therapeutic steps), and “Nothing”.

Conclusions

Anesthesiologists in two large tertiary care facilities in different parts of the world found coagulation management, especially in anticoagulated patients, complex. We identified the delayed diagnostic test results and their interpretation as challenges. Resources, treatment protocols and human factors such as team communication were perceived to facilitate management. Future studies should explore the challenges in smaller hospitals and other parts of the world and test new technologies addressing the identified difficulties.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01269-x.

Viscoelastic haemostatic assay augmented protocols for major trauma haemorrhage (ITACTIC): a randomized, controlled trial

PURPOSE

Contemporary trauma resuscitation prioritizes control of bleeding and uses major haemorrhage protocols (MHPs) to prevent and treat coagulopathy. We aimed to determine whether augmenting MHPs with Viscoelastic Haemostatic Assays (VHA) would improve outcomes compared to Conventional Coagulation Tests (CCTs).

METHODS

This was a multi-centre, randomized controlled trial comparing outcomes in trauma patients who received empiric MHPs, augmented by either VHA or CCT-guided interventions. Primary outcome was the proportion of subjects who, at 24 h after injury, were alive and free of massive transfusion (10 or more red cell transfusions). Secondary outcomes included 28-day mortality. Pre-specified subgroups included patients with severe traumatic brain injury (TBI).

RESULTS

Of 396 patients in the intention to treat analysis, 201 were allocated to VHA and 195 to CCT-guided therapy. At 24 h, there was no difference in the proportion of patients who were alive and free of massive transfusion (VHA: 67%, CCT: 64%, OR 1.15, 95% CI 0.76-1.73). 28-day mortality was not different overall (VHA: 25%, CCT: 28%, OR 0.84, 95% CI 0.54-1.31), nor were there differences in other secondary outcomes or serious adverse events. In pre-specified subgroups, there were no differences in primary outcomes. In the pre-specified subgroup of 74 patients with TBI, 64% were alive and free of massive transfusion at 24 h compared to 46% in the CCT arm (OR 2.12, 95% CI 0.84-5.34).

CONCLUSION

There was no difference in overall outcomes between VHA- and CCT-augmented-major haemorrhage protocols.

The Haemostasis Traffic Light, a user-centred coagulation management tool for acute bleeding situations: a simulation-based randomised dual-centre trial

The Haemostasis Traffic Light is a cognitive aid with a user-centred design to enhance and simplify situation awareness and decision-making during peri-operative bleeding. Its structure helps to prioritise therapeutic interventions according to the pathophysiology and the severity of the bleeding. This investigator-initiated, randomised, prospective, international, dual-centre study aimed to validate the Haemostasis Traffic Light by adapting it to the local coagulation protocols of two university hospitals. Between 9 January and 12 May 2020, we recruited 84 participants at the University Hospital Zurich, Switzerland, and the Italian Hospital of Buenos Aires, Argentina. Each centre included 21 resident and 21 staff anaesthetists. Participants were randomly allocated to either the text-based algorithm or the Haemostasis Traffic Light. All participants managed six bleeding scenarios using the same algorithm. In simulated bleeding scenarios, the design of the Haemostasis Traffic Light algorithm enabled more correctly solved cases, OR (95%CI) 7.23 (3.82-13.68), p < 0.001, and faster therapeutic decisions, HR (95%CI) 1.97 (1.18-3.29, p = 0.010). In addition, the tool improved therapeutic confidence, OR (95%CI) 4.31 (1.67-11.11, p = 0.003), and reduced perceived work-load coefficient (95%CI) -6.1 (-10.98 to -1.22), p = 0.020). This study provides empirical evidence for the importance of user-centred design in the development of haemostatic management protocols.

Targeted cryoprecipitate transfusion in severe traumatic haemorrhage

BACKGROUND

Severe traumatic haemorrhage is the leading cause of death in young adults. Trauma Induced Coagulopathy is a complex and multifactorial phenomenon associated with severe traumatic haemorrhage. Fibrinogen is one of the first coagulation factors to become depleted in TIC and evidence suggests that severely injured trauma patients with hypofibrinogenaemia have poor outcomes. It is postulated that early fibrinogen replacement can improve clinical outcomes. This study investigated cryoprecipitate transfusion in hyopfibrinogeneamic trauma patients.

METHODS

This retrospective, single center, observational study investigated the use of cryoprecipitate in severely injured trauma patients admitted to an Australian Level I Trauma Centre. The primary outcome was time to administration of cryoprecipitate after identification of hypofibrinogenaemia using ROTEM (FIBTEM A5). Data collected included demographics, ISS, laboratory values of coagulation and blood product usage.

RESULTS

71 patients received cryoprecipitate with a median time of 61 minutes [IQR 37-93] from FIBTEM A5 result to initial cryoprecipitate administration. At 24 hours following admission to ED, Clauss Fibrinogen levels increased by 1.30g/L [IQR 0.45-1.85] and FIBTEM A5 assay increased by 8mm [IQR 3.0-11.3]. Changes in both variables were highly significant (p<0.001) and Clauss Fibrinogen versus FIBTEM A5 values showed moderate to strong correlation (R=0.75-0.80).

CONCLUSION

This study demonstrated that early administration of cryoprecipitate was both feasible and efficacious in fibrinogen replacement in severe traumatic haemorrhage. High-level evidence supporting cryoprecipitate or fibrinogen concentrate replacement with regards to efficacy and feasibility is required to guide future clinical practice. This study provided baseline data to inform the design of further clinical trials investigating fibrinogen replacement in traumatic haemorrhage.

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.

Viscoelastic haemostatic assays and fibrinogen in paediatric acute traumatic coagulopathy: A comprehensive review

OBJECTIVE

Haemorrhage in paediatric trauma remains a significant cause of morbidity and mortality. Over recent years there has been increasing attention to the role of fibrinogen in traumatic haemorrhage and the association of low fibrinogen levels with poor patient outcomes. In addition, there has been a move towards using viscoelastic haemostatic assays (VHAs) to rapidly assess coagulation status and guide clinicians in the replacement of coagulation factors, including fibrinogen. In the paediatric population, there has been limited uptake of these principles and a paucity of data to support a change in practice. This paper summarises the available evidence in the published literature through a systematic review, presented in narrative format.

RESULTS

There is limited high-quality prospective data on the use of VHA in the management of acute traumatic coagulopathy in the paediatric population. While the use of fibrinogen early in major haemorrhage is becoming standard practice, there are currently no randomised prospective studies comparing fibrinogen concentrate to cryoprecipitate.

CONCLUSIONS

The early identification of hypo-fibrinogenemia and acute traumatic coagulopathy in paediatric trauma using VHA testing and subsequent early fibrinogen replacement with a concentrated off the shelf product is an attractive treatment option. However, there is currently insufficient high-level evidence to support the use of fibrinogen concentrate over cryoprecipitate in the paediatric trauma population. Pilot studies currently under way will go some way to addressing this important knowledge gap, and facilitate the design of larger definitive multi-centre randomised trials.

The role of evidence-based algorithms for rotational thromboelastometry-guided bleeding management

Rotational thromboelastometry (ROTEM) is a point-of-care viscoelastic method and enables to assess viscoelastic profiles of whole blood in various clinical settings. ROTEM-guided bleeding management has become an essential part of patient blood management (PBM) which is an important concept in improving patient safety. Here, ROTEM testing and hemostatic interventions should be linked by evidence-based, setting-specific algorithms adapted to the specific patient population of the hospitals and the local availability of hemostatic interventions. Accordingly, ROTEM-guided algorithms implement the concept of personalized or precision medicine in perioperative bleeding management (‘theranostic’ approach). ROTEM-guided PBM has been shown to be effective in reducing bleeding, transfusion requirements, complication rates, and health care costs. Accordingly, several randomized-controlled trials, meta-analyses, and health technology assessments provided evidence that using ROTEM-guided algorithms in bleeding patients resulted in improved patient’s safety and outcomes including perioperative morbidity and mortality. However, the implementation of ROTEM in the PBM concept requires adequate technical and interpretation training, education and logistics, as well as interdisciplinary communication and collaboration.

Rapid paper diagnostic for plasma fibrinogen concentration

Fibrinogen is one of the first proteins to be depleted in heavily bleeding patients. In this study, we have developed a new paper-based diagnostic to quantify the fibrinogen concentration in blood at room temperature.

Sudden Arrhythmic Death During Exercise: A Post-Mortem Genetic Analysis

BACKGROUND

Sudden cardiac death is a natural and unexpected death that occurs within 1 h of the first symptom. Most sudden cardiac deaths occur during exercise, mostly as a result of myocardial infarction. After autopsy, some cases, especially in the young, are diagnosed as cardiomyopathies or remain without a conclusive cause of death. In both situations, genetic alterations may explain the arrhythmia.

OBJECTIVE

Our aim was to identify a genetic predisposition to sudden cardiac death in a cohort of post-mortem cases of individuals who died during exercise, with a structurally normal heart, and were classified as arrhythmogenic death.

METHODS

We analyzed a cohort of 52 post-mortem samples from individuals <50 years old who had a negative autopsy. Next-generation sequencing technology was used to screen genes associated with sudden cardiac death.

RESULTS

Our cohort showed a male prevalence (12:1). Half of the deaths occurred in individuals 41-50 years of age. Running was the most common exercise activity during the fatal event, accounting for 46.15% of cases. Genetic analysis identified 83 rare variants in 37 samples (71.15% of all samples). Of all rare variants, 36.14% were classified as deleterious, being present in 53.84% of all cases.

CONCLUSIONS

A comprehensive analysis of sudden cardiac death-related genes in individuals who died suddenly while exercising enabled the identification of potentially causative variants. However, many genetic variants remain of indeterminate significance, thus further work is needed before clinical translation. Nonetheless, comprehensive genetic analysis of individuals who died during exercise enables the detection of potentially causative variants and helps to identify at-risk relatives.

Damage-associated molecular patterns in resuscitated hemorrhagic shock are mitigated by peritoneal fluid administration

Conventional resuscitation (CR) of hemorrhagic shock (HS), a significant cause of trauma mortality, is intravenous blood and fluids. CR restores central hemodynamics, but vital organ flow can drop, causing hypoperfusion, hypoxia, damage-associated molecular patterns (DAMPs), and remote organ dysfunction (i.e., lung). CR plus direct peritoneal resuscitation (DPR) prevents intestinal and hepatic hypoperfusion. We hypothesized that DPR prevents lung injury in HS/CR by altering DAMPs. Anesthetized male Sprague-Dawley rats were randomized to groups ( n = 8/group) in one of two sets: 1) sham (no HS, CR, or DPR), 2) HS/CR (HS = 40% mean arterial pressure (MAP) for 60 min, CR = shed blood + 2 volumes normal saline), or 3) HS/CR + DPR. The first set underwent whole lung blood flow by colorimetric microspheres. The second set underwent tissue collection for Luminex, ELISAs, and histopathology. Lipopolysaccharide (LPS) and DAMPs were measured in serum and/or lung, including cytokines, hyaluronic acid (HA), high-mobility group box 1 (HMGB1), Toll-like receptor 4 (TLR4), myeloid differentiation primary response 88 protein (MYD88), and TIR-domain-containing adapter-inducing interferon-β (TRIF). Statistics were by ANOVA and Tukey-Kramer test with a priori P < 0.05. HS/CR increased serum LPS, HA, HMGB1, and some cytokines [interleukin (IL)-1α, IL-1β, IL-6, and interferon-γ]. Lung TLR4 and MYD88 were increased but not TRIF compared with Shams. HS/CR + DPR decreased LPS, HA, cytokines, HMGB1, TLR4, and MYD88 levels but did not alter TRIF compared with HS/CR. The data suggest that gut-derived DAMPs can be modulated by adjunctive DPR to prevent activation of lung TLR-4-mediated processes. Also, DPR improved lung blood flow and reduced lung tissue injury. Adjunctive DPR in HS/CR potentially improves morbidity and mortality by downregulating the systemic DAMP response.

Position of the French Working Group on Perioperative Haemostasis (GIHP) on viscoelastic tests: What role for which indication in bleeding situations?

PURPOSE

Viscoelastic tests (VETs), thromboelastography (TEG^®) and thromboelastometry (ROTEM^®) are global tests of coagulation performed on whole blood. They evaluate the mechanical strength of a clot as it builds and develops after coagulation itself. The time required to obtain haemostasis results remains a major problem for clinicians dealing with bleeding, although some teams have developed a rapid laboratory response strategy. Indeed, the value of rapid point-of-care diagnostic devices such as VETs has increased over the years. However, VETs are not standardised and there are few recommendations from the learned societies regarding their use. In 2014, the recommendations of the International Society of Thrombosis and Haemostasis (ISTH) only concerned haemophilia. The French Working Group on Perioperative haemostasis (GIHP) therefore proposes to summarise knowledge on the clinical use of these techniques in the setting of emergency and perioperative medicine.

METHODS

A review of the literature.

PRINCIPAL FINDINGS

The role of the VETs seems established in the management of severe trauma and in cardiac surgery, both adult and paediatric. In other situations, their role remains to be defined: hepatic transplantation, postpartum haemorrhage, and non-cardiac surgery. They must be part of the global management of haemostasis based on algorithms defined in each centre and for each population of patients. Their position at the bedside or in the laboratory is a matter of discussion between clinicians and biologists.

CONCLUSION

VETs must be included in algorithms. In consultation with the biology laboratory, these devices should be situated according to the way each centre functions.

Nano- and micro-materials in the treatment of internal bleeding and uncontrolled hemorrhage

Internal bleeding is defined as the loss of blood that occurs inside of a body cavity. After a traumatic injury, hemorrhage accounts for over 35% of pre-hospital deaths and 40% of deaths within the first 24 hours. Coagulopathy, a disorder in which the blood is not able to properly form clots, typically develops after traumatic injury and results in a higher rate of mortality. The current methods to treat internal bleeding and coagulopathy are inadequate due to the requirement of extensive medical equipment that is typically not available at the site of injury. To discover a potential route for future research, several current and novel treatment methods have been reviewed and analyzed. The aim of investigating different potential treatment options is to expand available knowledge, while also call attention to the importance of research in the field of treatment for internal bleeding and hemorrhage due to trauma.

The research agenda for trauma critical care

In this research agenda on the acute and critical care management of trauma patients, we concentrate on the major factors leading to death, namely haemorrhage and traumatic brain injury (TBI). In haemostasis biology, the results of randomised controlled trials have led to the therapeutic focus moving away from the augmentation of coagulation factors (such as recombinant factor VIIa) and towards fibrinogen supplementation and administration of antifibrinolytics such as tranexamic acid. Novel diagnostic techniques need to be evaluated to determine whether an individualised precision approach is superior to current empirical practice. The timing and efficacy of platelet transfusions remain in question, while new blood products need to be developed and evaluated, including whole blood variants, lyophilised products and novel red cell storage modalities. The current cornerstones of TBI management are intracranial pressure control, maintenance of cerebral perfusion pressure and avoidance of secondary insults (such as hypotension, hypoxaemia, hyperglycaemia and pyrexia). Therapeutic hypothermia and decompressive craniectomy are controversial therapies. Further research into these strategies should focus on identifying which subgroups of patients may benefit from these interventions. Prediction of the long-term outcome early after TBI remains challenging. Early magnetic resonance imaging has recently been evaluated for predicting the long-term outcome in mild and severe TBI. Novel biomarkers may also help in outcome prediction and may predict chronic neurological symptoms. For trauma in general, rehabilitation is complex and multidimensional, and the optimal timing for commencement of rehabilitation needs investigation. We propose priority areas for clinical trials in the next 10 years.

Fibrinogen Early In Severe Trauma studY (FEISTY): study protocol for a randomised controlled trial

BACKGROUND

Haemorrhage is a leading cause of death in severe trauma. Fibrinogen plays a critical role in maintaining haemostasis in traumatic haemorrhage. Early fibrinogen replacement is recommended by several international trauma guidelines using either fibrinogen concentrate (FC) or cryoprecipitate (Cryo). There is limited evidence to support one product over the other with widespread geographic and institutional variation in practice. This pilot trial is the first randomised controlled trial comparing FC to Cryo in traumatic haemorrhage.

METHODS/DESIGN

The Fibrinogen Early In Severe Trauma studY (FEISTY) is an exploratory, multicentre, randomised controlled trial comparing FC to Cryo for fibrinogen supplementation in traumatic haemorrhage. This trial will utilise thromboelastometry (ROTEM®) to guide and dose fibrinogen supplementation. The trial will recruit 100 trauma patients at four major trauma centres in Australia. Adult trauma patients with evidence of haemorrhage will be enrolled on arrival in the trauma unit and randomised to receiving fibrinogen supplementation with either FC or Cryo. The primary outcome is the differential time to fibrinogen supplementation. There are a number of predetermined secondary outcomes including: effects of the intervention on plasma fibrinogen levels, feasibility assessments and clinical outcomes including transfusion requirements and mortality.

DISCUSSION

The optimal method for replacing fibrinogen in traumatic haemorrhage is fiercely debated. In this trial the feasibility and efficacy of fibrinogen supplementation using FC will be compared to Cryo. The results of this pilot study will facilitate the design of a larger trial with sufficient power to address patient-centred outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov, ID: NCT02745041 . Registered 4 May 2016.

Haemotherapy algorithm for the management of trauma-induced coagulopathy: an Australian perspective

PURPOSE OF REVIEW

Recent advances in the understanding of the pathophysiological processes associated with traumatic haemorrhage and trauma-induced coagulopathy have resulted in improved outcomes for seriously injured trauma patients. However, a significant number of trauma patients still die from haemorrhage. This article reviews the various transfusion strategies utilized in the management of traumatic haemorrhage and describes the major haemorrhage protocol (MHP) strategy employed by an Australian trauma centre.

RECENT FINDINGS

Few topics in trauma resuscitation incite as much debate and controversy as to what constitutes the 'ideal' MHP. There is a widespread geographical and institutional variation in clinical practice. Three strategies are commonly utilized; fixed ratio major haemorrhage protocol (FRMHP), viscoelastic haemostatic assay (VHA)-guided MHP and hybrid MHP. The majority of trauma centres utilize an FRMHP and there is high-level evidence to support the use of high blood product ratios. It can be argued that the FRMHP is too simplistic to be applied to all trauma patients and that the use of VHA-guided MHP with predominant factor concentrate transfusion can allow rapid individualized interventions. In between these two strategies is a hybrid MHP, combining early FRMHP with subsequent VHA-guided transfusion.

SUMMARY

There are advantages and disadvantages to each of the various MHP strategies and the evidence base to support one above another with any certainty is lacking at this time. One strategy cannot be considered superior to the other and the choice of MHP is dependent on interpretation of the current literature and local institutional logistical considerations. A number of exciting studies are currently underway that will certainly increase the evidence base and help inform clinical practice.

Fibrinogen in traumatic haemorrhage: A narrative review

Haemorrhage in the setting of severe trauma is associated with significant morbidity and mortality. There is increasing awareness of the important role fibrinogen plays in traumatic haemorrhage. Fibrinogen levels fall precipitously in severe trauma and the resultant hypofibrinogenaemia is associated with poor outcomes. Hence, it has been postulated that early fibrinogen replacement in severe traumatic haemorrhage may improve outcomes, although, to date there is a paucity of high quality evidence to support this hypothesis. In addition there is controversy regarding the optimal method for fibrinogen supplementation. We review the current evidence regarding the role of fibrinogen in trauma, the rationale behind fibrinogen supplementation and discuss current research.