Diagnosis of early coagulation abnormalities in trauma patients by rotation thrombelastography

In vitro evaluation of a new viscoelastometry-based point-of-care analyzer

INTRODUCTION

The VCM is a point-of-care analyzer using a new viscoelastometry technique for rapid assessment of hemostasis on fresh whole blood. Its characteristics would make it suitable for use in austere environments. The purpose of this study was to evaluate the VCM in terms of repeatability, reproducibility and interanalyzer correlation, reference values in our population, correlation with standard coagulation assays and platelet count, correlation with the TEG5000 analyzer and resistance to stress conditions mimicking an austere environment.

METHODS

Repeatability, reproducibility, and interanalyzer correlation were performed on quality control samples (n = 10). Reference values were determined from blood donor samples (n = 60). Correlations with standard biological assays were assessed from ICU patients (n = 30) and blood donors (n = 60) samples. Correlation with the TEG5000 was assessed from blood donor samples. Evaluation of vibration resistance was performed on blood donor (n = 5) and quality control (n = 5) samples.

RESULTS

The CVs for repeatability and reproducibility ranged from 0% to 11%. Interanalyzer correlation found correlation coefficients (r2) ranging from 0.927 to 0.997. Our reference values were consistent with those provided by the manufacturer. No robust correlation was found with conventional coagulation tests. The correlation with the TEG5000 was excellent with r2 ranging from 0.75 to 0.92. Resistance to stress conditions was excellent.

CONCLUSION

The VCM analyzer is a reliable, easy-to-use instrument that correlates well with the TEG5000. Despite some logistical constraints, the results suggest that it can be used in austere environments. Further studies are required before its implementation.

Electrochemical Monitoring in Anticoagulation Therapy

The process of blood coagulation, wherein circulating blood transforms into a clot in response to an internal or external injury, is a critical physiological mechanism. Monitoring this coagulation process is vital to ensure that blood clotting neither occurs too rapidly nor too slowly. Anticoagulants, a category of medications designed to prevent and treat blood clots, require meticulous monitoring to optimise dosage, enhance clinical outcomes, and minimise adverse effects. This review article delves into the various stages of blood coagulation, explores commonly used anticoagulants and their targets within the coagulation enzyme system, and emphasises the electrochemical methods employed in anticoagulant testing. Electrochemical sensors for anticoagulant monitoring are categorised into two types. The first type focuses on assays measuring thrombin activity via electrochemical techniques. The second type involves modified electrode surfaces that either directly measure the redox behaviours of anticoagulants or monitor the responses of standard redox probes in the presence of these drugs. This review comprehensively lists different electrode compositions and their detection and quantification limits. Additionally, it discusses the potential of employing a universal calibration plot to replace individual drug-specific calibrations. The presented insights are anticipated to significantly contribute to the sensor community's efforts in this field.

A global assessment of hemostatic function of healthy allogeneic stem cell donors undergoing apheresis by rotational thromboelastometry

INTRODUCTION

Peripheral blood stem cell (PBSC) collection via apheresis requires the administration of granulocyte colony-stimulating factor (filgrastim) to stem cell donors. Several reports have shown that filgrastim administration and apheresis procedure induce a hypercoagulable state across PBSC collection, which might predispose certain donors to thrombotic complications.

METHODS

We evaluated the hemostatic functions of healthy allogeneic stem cell donors by rotational thromboelastometry (ROTEM). Blood samples from healthy donors (n = 30) were collected at defined time points: before filgrastim (baseline), on the day of apheresis before and after the procedure, and 1 week after apheresis.

RESULTS

The results indicated that hemostatic changes are temporary since all parameters in both EXTEM and INTEM assays are restored to their initial values 1 week after the apheresis.

CONCLUSION

We concluded that stem cell apheresis does not induce a hypercoagulable state in healthy donors. This is the first study evaluating the hemostatic functions of stem cell donors by ROTEM.

Viscoelastic Testing Methods

Viscoelastic testing methods examine the real-time formation of a clot in a whole blood sample, and include thromboelastography (TEG), rotational thromboelastometry (ROTEM), and several other testing platforms. They allow for concurrent assessment of multiple aspects of clotting, including plasmatic coagulation factors, platelets, fibrinogen, and the fibrinolytic pathway. This testing is rapid and may be performed at the point-of-care, allowing for prompt identification of coagulopathies to guide focused and rational administration of blood products as well as the identification of anticoagulant effect. With recent industry progression towards user-friendly, cartridge-based, portable instruments, viscoelastic testing has emerged in the 21st century as a powerful tool to guide blood transfusions in the bleeding patient, and to identify and treat both bleeding and thrombotic conditions in many operative settings, including trauma surgery, liver transplant surgery, cardiac surgery, and obstetrics. In these settings, the use of transfusion algorithms guided by viscoelastic testing data has resulted in widespread improvements in patient blood management as well as modest improvements in select patient outcomes. To address the increasingly wide adoption of viscoelastic methods and the growing number of medical and laboratory personnel tasked with implementing, performing, and interpreting these methods, this chapter provides an overview of the history, physiology, and technology behind viscoelastic testing, as well as a practical review of its clinical utility and current evidence supporting its use. Also included is a review of testing limitations and the contextual role played by viscoelastic methods among all coagulation laboratory testing.

Effect of bone cement sealing of the intramedullary femoral canal on coagulation status after total knee arthroplasty: a retrospective thromboelastography study

BACKGROUND

The main objective of this study was to investigate whether the use of bone cement in total knee arthroplasty (TKA) has an effect on postoperative coagulation status and bleeding.

METHODS

153 patients who underwent unilateral TKA between September 2019 and February 2023 were collected and divided into Bone and Cement&Bone groups according to whether bone cement was used to seal the bone medullary canal intraoperatively. Routine blood and thromboelastography (TEG) examinations were performed on the day before, the first day and the seventh day after surgery; postoperative bleeding, drainage, transfusion rate and the number of people suffering from deep venous thrombosis (DVT) were recorded.

RESULTS

There were no significant differences between the two groups in terms of baseline clinical characteristics before surgery (P > 0.05). In terms of TEG indicators, the coagulation index (CI) of the Bone&Cement group was lower than that of the Bone group on the first postoperative day and on the seventh postoperative day (P < 0.05). The CI of patients in the Bone group on the first postoperative day was lower than that of the preoperative day (P < 0.05); in terms of blood loss, the total blood loss and occult blood loss were lower in the Bone&Cement group than in the Bone group (P < 0.05). In addition, there was no significant difference in postoperative drainage,transfusion rate and the incidence of DVT between the two groups.

CONCLUSION

Blocking the intramedullary canal of the femur with bone cement during TKA improves relative postoperative hypocoagulation and reduces postoperative blood loss, although there is no significant effect on transfusion rates, drainage and DVT.

[Viscoelasticity-based point of care coagulation diagnostics in the context of resuscitation room management of severely injured and bleeding trauma patients : Diagnostics and treatment of trauma-induced coagulopathy]

Uncontrolled bleeding with associated trauma-induced coagulopathy (TIC) remains the leading cause of preventable death after severe trauma. Meanwhile, TIC is recognized as a separate clinical entity with substantial impact on downstream morbidity and mortality. In clinical practice severely injured and bleeding patients are often still being treated according to established damage control surgery (DCS) procedures with surgical bleeding control and empirical transfusion of classical blood products in predefined ratios in the sense of damage control resuscitation (DCR); however, algorithms are also available, which have been constructed from established viscoelasticity-based point of care (POC) diagnostic procedures and target value-oriented treatments. The latter enables a timely qualitative assessment of coagulation function from whole blood at bedside and provides rapid and clinically useful information on the presence, development and dynamics of the coagulation disorder. The early implementation of viscoelasticity-based POC procedures in the context of resuscitation room management of severely injured and bleeding patients was uniformly associated with reductions in potentially harmful blood products, especially overtransfusions, and an overall improvement in outcome including survival. The present article reviews the clinical questions around the use of viscoelasticity-based procedures as well as recommendations for the early and acute management of bleeding trauma patients taking the current literature into account.

Blood coagulation test abnormalities in trauma patients detected by sonorheometry: a retrospective cohort study

Background

Traumatic hemorrhage guidelines include point-of-care viscoelastic tests as a standard of care. Quantra (Hemosonics) is a device based on sonic estimation of elasticity via resonance (SEER) sonorheometry to assess whole blood clot formation.

Objectives

Our study aimed to assess the ability of an early SEER evaluation to detect blood coagulation test abnormalities in trauma patients.

Methods

We conducted an observational retrospective cohort study with data collected at hospital admission of consecutive multiple trauma patients from September 2020 to February 2022 at a regional level 1 trauma center. We performed a receiving operator characteristic curve analysis to determine the ability of the SEER device to detect blood coagulation test abnormalities. Four values on the SEER device were analyzed: clot formation time, clot stiffness (CS), platelet contribution to CS, and fibrinogen contribution to CS.

Results

A total of 156 trauma patients were analyzed. The clot formation time value predicted an activated partial thromboplastin time ratio of >1.5 with an area under the curve (AUC) of 0.93 (95% CI, 0.86-0.99). The AUC of the CS value in detecting an international normalized ratio of prothrombin time of >1.5 was 0.87 (95% CI, 0.79-0.95). The AUC of fibrinogen contribution to CS to detect a fibrinogen concentration of <1.5 g/L was 0.87 (95% CI, 0.80-0.94). The AUC of platelet contribution to CS to detect a platelet concentration of <50 G/L was 0.99 (95% CI, 0.99-1.00).

Conclusion

Our results suggest that the SEER device may be useful for the detection of blood coagulation test abnormalities at trauma admission.

A prospective, controlled study on the utility of rotational thromboelastometry in surgery for acute type A aortic dissection

To evaluate the hemostatic system with ROTEM in patients undergoing surgery for acute type aortic dissection (ATAAD) using elective aortic procedures as controls. This was a prospective, controlled, observational study. The study was performed at a tertiary referral center and university hospital. Twenty-three patients with ATAAD were compared to 20 control patients undergoing elective surgery of the ascending aorta or the aortic root. ROTEM (INTEM, EXTEM, HEPTEM and FIBTEM) was tested at 6 points in time before, during and after surgery for ATAAD or elective aortic surgery. The ATAAD group had an activated coagulation coming into the surgical theatre. The two groups showed activation of both major coagulation pathways during surgery, but the ATAAD group consistently had larger deficiencies. Reversal of the coagulopathy was successful, although none of the groups reached elective baseline until postoperative day 1. ROTEM did not detect low levels of clotting factors at heparin reversal nor low levels of platelets. This study demonstrated that ATAAD is associated with a coagulopathic state. Surgery causes additional damage to the hemostatic system in ATAAD patients as well as in patients undergoing elective surgery of the ascending aorta or the aortic root. ROTEM does not adequately catch the full coagulopathy in ATAAD. A transfusion protocol in ATAAD should be specifically created to target this complex coagulopathic state and ROTEM does not negate the need for routine laboratory tests.

Characterization of 2 Different Prothrombin Complex Concentrates by Different Hemostatic Assays in an In Vitro Hemodilution Model

BACKGROUND

Viscoelastically guided coagulation factor concentrate-based algorithms for the treatment of trauma-induced coagulopathy include the administration of prothrombin complex concentrates (PCCs). However, the exact role of PCC preparations in this context is a matter of debate. Particularly, the ideal diagnostic trigger for their administration and potential differences between heparin-containing and heparin-free preparations remain unclear. We investigated the hypothesis that 2 different PCCs might have distinct influences on in vitro blood coagulation.

METHODS

We conducted a direct comparison of 2 commercially available PCC preparations (the heparin-containing Beriplex P/N and the heparin-free Cofact) in an in vitro hemodilution model. Sole fibrinogen substitution served as the control group. To characterize the hemostatic changes, we utilized conventional coagulation tests, a thrombin generation assay (TGA), and 2 different viscoelastic hemostatic assays (VHAs; ROTEM delta and ClotPro).

RESULTS

Irrespective of the diagnostic assay used, no significant differences between the 2 PCC groups were observed. Fibrinogen levels remained stable from the baseline throughout every dilution level. The control group already showed an increased endogenous thrombin potential (ETP; nM·L -1 ·min -1 ) at all dilution levels compared to baseline (baseline, 2829.4 (432.8); 40% dilution, 4211.7 (391.6); 60% dilution, 4290.9 (300.8); 80% dilution, 3861.4 (303.5); all P < .001). Spiking with both PCC preparations led to a further-pronounced thrombin elevation in comparison to the control group (ETP at 40% dilution, PCC1: 4913.3 [370.2], PCC2: 4988.1 [265.7]; 60% dilution, PCC1: 5174.5 [234.7], PCC2: 5390.4 [334.9]; 80% dilution, PCC1: 5253.8 [357.9], PCC2: 5392.6 [313.4]; all P < .001). Conventional coagulation tests did not mirror the TGA results. Despite increased thrombin generation, prothrombin time was significantly prolonged at all dilution levels for the control group, and both PCC groups exhibited significant prolongations at the 60% and 80% dilution levels (all P < .001) compared to baseline. Similarly, VHA did not depict the thrombin elevation. Furthermore, descriptive analyses revealed relevant differences between the 2 VHA devices, particularly at baseline.

CONCLUSIONS

Both PCC preparations (ie, irrespective of heparin content) induced significant elevation of thrombin generation, which was not depicted by conventional coagulation tests or VHA. Our in vitro results suggest that diagnostic assays routinely used to guide PCC administration might not adequately reflect thrombin generation in bleeding patients.

Traumatic Brain Injury Induces a Differential Immune Response in Polytrauma Patients; Prospective Analysis of CD69 Expression on T Cells and Platelet Expansion

Background: Accidents and injuries are the leading causes of mortality in young people. CD4+ regulatory T cells (CD4+ Tregs), Th17 cells and platelets could be identified as key players in post-traumatic immunological dysfunction, which is a common cause of late mortality in trauma patients. The mechanisms of activation of these cell types and their interaction remain mostly unclear. Since CD69 is not only a leukocyte marker but has also immunoregulatory functions, we postulate a role for CD69 after trauma. The present study investigates the expression of CD69 on CD4+ Tregs and Th17 cells, as well as the posttraumatic expansion of platelets and hemostatic function. Subgroup analysis was performed to assess the differences between polytrauma patients with and without severe traumatic brain injury (TBI). Methods: In this non-interventional prospective clinical trial, we analyzed sequential blood samples over a period of 10 days from 30 patients after multiple traumas with an ISS ≥ 16. Platelet function was assessed by rotational thromboelastometry (ROTEM analysis). CD4+ Tregs and Th17 cells were stained with surface markers and analyzed by flow cytometry. Results: We were able to demonstrate a significantly increased expression of CD69 on CD4+ Tregs after trauma. Subgroup analysis revealed that the absence of severe TBI is associated with a significantly higher expression of CD69 on CD4+ Tregs and on Th17 cells. Platelets expanded and showed signs of dysfunction, while an overall tendency of posttraumatic hypercoagulation was detected. Conclusions: Our results support the concept of injury-specific immune responses and add to a further understanding of the complex pathophysiology of post-traumatic immune dysfunction.

Evaluation of novel coagulation and platelet function assays in patients with chronic kidney disease

BACKGROUND

Hemostasis evaluation in chronic kidney disease (CKD) is critical for optimal management of thrombotic and bleeding events. Standard coagulation screens are inadequate for predicting coagulopathy in CKD.

OBJECTIVE

To evaluate hemostasis parameters in patients with different stages of CKD using novel coagulation assays.

PATIENTS/METHODS

Cross-sectional study of 30 healthy controls (HC) and 120 CKD patients (10 Stage 2, 20 Stage 3, 20 Stage 4, 20 Stage 5 not requiring renal replacement therapy, 20 transplant, 10 newly started on hemodialysis [HD], 20 established on HD). Standard laboratory tests were performed in addition to rotational thromboelastometry (ROTEM), multiple electrode aggregometry (MEA), thrombin generation assays, D-dimer, and markers of thrombogenesis (thrombin-antithrombin [TAT]), fibrinolysis, and endothelial activation (intercellular adhesion molecule-1 [ICAM-1]).

RESULTS

D-dimer, TAT, and ICAM-1 concentrations were significantly higher in patients with CKD than HC (P < .01). ROTEM maximum clot firmness was significantly higher in patients than in HC (P < .01). In CKD Stage 5 patients (pre-HD and started HD) adenosine diphosphate and thrombin receptor activating peptide MEA tests were significantly lower than HC indicating platelet aggregation defect (P < .05). Multivariate analysis confirmed the direct effect of estimated glomerular filtration rate (eGFR) in the variance of ROTEM and MEA tests. Endogenous thrombin potential and peak thrombin were not statistically different between groups, but Stage 5 CKD patients had prolonged lag time (7.91 vs. 6.33, P < .001) and time to thrombin peak (10.8 vs. 9.5, P < .05) compared to HC.

CONCLUSIONS

Patients with CKD exhibit features of concomitant hypercoagulability measured by ROTEM and platelet dysfunction measured with MEA. eGFR was an independent determinant of platelet dysfunction and hypercoagulability.

A predictive model for postoperative progressive haemorrhagic injury in traumatic brain injuries

Background

Progressive haemorrhagic injury after surgery in patients with traumatic brain injury often results in poor patient outcomes. This study aimed to develop and validate a practical predictive tool that can reliably estimate the risk of postoperative progressive haemorrhagic injury (PHI) in patients with traumatic brain injury (TBI).

Methods

Data from 645 patients who underwent surgery for TBI between March 2018 and December 2020 were collected. The outcome was postoperative intracranial PHI, which was assessed on postoperative computed tomography. The least absolute shrinkage and selection operator (LASSO) regression model, univariate analysis, and Delphi method were applied to select the most relevant prognostic predictors. We combined conventional coagulation test (CCT) data, thromboelastography (TEG) variables, and several predictors to develop a predictive model using binary logistic regression and then presented the results as a nomogram. The predictive performance of the model was assessed with calibration and discrimination. Internal validation was assessed.

Results

The signature, which consisted of 11 selected features, was significantly associated with intracranial PHI (p < 0.05, for both primary and validation cohorts). Predictors in the prediction nomogram included age, S-pressure, D-pressure, pulse, temperature, reaction time, PLT, prothrombin time, activated partial thromboplastin time, FIB, and kinetics values. The model showed good discrimination, with an area under the curve of 0.8694 (95% CI, 0.8083–0.9304), and good calibration.

Conclusion

This model is based on a nomogram incorporating CCT and TEG variables, which can be conveniently derived at hospital admission. It allows determination of this individual risk for postoperative intracranial PHI and will facilitate a timely intervention to improve outcomes.

Application of Rotational Thromboelastometry in Patients with Acute Promyelocytic Leukemia

Introduction

Hemorrhagic early death (HED) remains a major cause of treatment failure among patients with acute promyelocytic leukemia (APL). We aimed to investigate the prognostic potential of rotational thromboelastometry (ROTEM) for bleeding in patients with APL.

Materials and Methods

31 newly-diagnosed APL patients (median age of 40 years; 14 female/17 male) that underwent treatment at the Clinic of Hematology UCCS from 2016-2020 with all-trans retinoic acid and anthracyclines were recruited. CBCs (complete blood count), conventional coagulation tests (CCTs), and ROTEM parameters obtained before treatment initiation were evaluated.

Results

All patients demonstrated at least one ROTEM parameter out of the reference range. ROTEM parameters associated with significant hemorrhage were EXTEM clotting time (CT) (P = 0.041) and INTEM amplitude 10 (A10) (P = 0.039), however, only EXTEM CT (P = 0.036) was associated with HED. Among CBCs and CCTs, only platelets were associated with significant bleeding (P = 0.015), while D-dimer was associated with both bleeding and HED (P = 0.001 and P = 0.002, respectively).

Conclusion

Our results indicate that ROTEM parameters may reveal hypocoagulability in APL patients and have the potential to improve current hemorrhage prognostic methods. Additionally, these results suggest the combination of ROTEM and CCTs might be useful in identifying patients at risk for HED.

Which injured patients with moderate fibrinogen deficit need fibrinogen supplementation?

Background

In severely injured patients, fibrinogen supplementation is recommended when fibrinogenemia is < 1.5 g L⁻¹, but some teams have suggested to use higher thresholds (fibrinogenemia < 2.0 g L⁻¹ or FIBTEM clot amplitude at 5 min (A5) values < 11 mm). The goal of this study was to specify in patients with a moderate fibrinogen deficit (MFD) whether some admission characteristics would be associated with fibrinogen administration at 24 h.

Methods

Prospective analysis of retrospectively collected data from a trauma registry (01/2011–12/2019). MFD-C was defined by a fibrinogenemia 1.51–1.99 g L⁻¹ or the corresponding FIBTEM-A5 values (MFD-A5) that were determined from linear regression and ROC curve analysis. Administration of fibrinogen were described according to the following admission parameters: shock index (SI) > 1, hemoglobin level < 110 g L⁻¹ (HemoCue®), and base deficit > 5 mEq L⁻¹. Data are expressed as count (%), median [IQR].

Results

1076 patients were included in the study and 266 (27%) had MFD-C, among them, 122/266 (46%) received fibrinogen. Patients with MFD-C who received fibrinogen were more severely injured (ISS: 27 [19–36] vs. 24 [17–29]) and had more impaired vital signs (base deficit: 5.4 [3.6–7.8] vs. 3.8 [2.0–6.0]). Linear regression analysis found a positive correlation between fibrinogen level and FIBTEM-A5 (r: 0.805). For a fibrinogen level < 1.5 g L⁻¹ and < 2.0 g L⁻¹, FIBTEM-A5 thresholds were 6 mm (sensitivity 85%, specificity 83%, AUC: 0.934) and 9 mm (sensitivity 84%, specificity 69%, AUC: 0.874), respectively. MFD-A5 values (185 (27%) patients) were defined as a FIBTEM-A5 between 7 and 9 mm. More than 50% of MFD-C patients presenting a SI > 1, a hemoglobin level < 110 g L⁻¹, or a base deficit > 5.0 mEq L⁻¹ received fibrinogen. The relative risk [95% CI] for fibrinogen administration (SI > 1) were 1.39 [1.06–1.82] for MFD-C, and 2.17 [1.48–3.19] for MFD-A5. Results were not modified after adjustment on the ISS.

Conclusions

We have shown in this study an association between shock parameters and fibrinogen administration. Further studies are needed to determine how these parameters may be used to guide fibrinogen administration in trauma patients with MFD.

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.

Viscoelastic Hemostatic Assays for Postpartum Hemorrhage

This article discusses the importance and effectiveness of viscoelastic hemostatic assays (VHAs) in assessing hemostatic competence and guiding blood component therapy (BCT) in patients with postpartum hemorrhage (PPH). In recent years, VHAs such as thromboelastography and rotational thromboelastometry have increasingly been used to guide BCT, hemostatic adjunctive therapy and prohemostatic agents in PPH. The three pillars of identifying hemostatic competence include clinical observation, common coagulation tests, and VHAs. VHAs are advantageous because they assess the cumulative contribution of all components of the blood throughout the entire formation of a clot, have fast turnaround times, and are point-of-care tests that can be followed serially. Despite these advantages, VHAs are underused due to poor understanding of correct technique and result interpretation, a paucity of widespread standardization, and a lack of large clinical trials. These VHAs can also be used in cases of uterine atony, preeclampsia, acute fatty liver of pregnancy, amniotic fluid embolism, placental abruption, genital tract trauma, surgical trauma, and inherited and prepartum acquired coagulopathies. There exists an immediate need for a point-of-care test that can equip obstetricians with rapid results on developing coagulopathic states. The use of VHAs in predicting and treating PPH, although in an incipient state, can fulfill this need.

First-Line Administration of Fibrinogen Concentrate in the Bleeding Trauma Patient: Searching for Effective Dosages and Optimal Post-Treatment Levels Limiting Massive Transfusion-Further Results of the RETIC Study

Fibrinogen supplementation is recommended for treatment of severe trauma hemorrhage. However, required dosages and aimed for post-treatment fibrinogen levels remain a matter of discussion. Within the published RETIC study, adult patients suffering trauma-induced coagulopathy were randomly assigned to receive fibrinogen concentrate (FC) as first-line (n = 50) or crossover rescue (n = 20) therapy. Depending on bodyweight, a single dose of 3, 4, 5, or 6 g FC was administered and repeated if necessary (FibA10 < 9 mm). The dose-dependent response (changes in plasma fibrinogen and FibA10) was analyzed. Receiver operating characteristics (ROC) analysis regarding the need for massive transfusion and correlation analyses regarding fibrinogen concentrations and polymerization were performed. Median FC single doses amounted to 62.5 (57 to 66.66) mg·kg⁻¹. One FC single-dose sufficiently corrected fibrinogen and FibA10 (median fibrinogen 213 mg·dL⁻¹, median FibA10 11 mm) only in patients with baseline fibrinogen above 100 mg·dL⁻¹ and FibA10 above 5 mm, repeated dosing was required in patients with lower baseline fibrinogen/FibA10. Fibrinogen increased by 83 or 107 mg·dL⁻¹ and FibA10 by 4 or 4.5 mm after single or double dose of FC, respectively. ROC curve analysis revealed post-treatment fibrinogen levels under 204.5 mg·dL⁻¹ to predict the need for massive transfusion (AUC 0.652; specificity: 0.667; sensitivity: 0.688). Baseline fibrinogen/FibA10 levels should be considered for FC dosing as only sufficiently corrected post-treatment levels limit transfusion requirements.

Evaluation of trauma-induced coagulopathy in the fibrinogen in the initial resuscitation of severe trauma trial

BACKGROUND

Coagulopathic bleeding is frequently present after major trauma. However, trauma-induced coagulopathy (TIC) remains incompletely understood. This laboratory analysis of blood samples derived from our completed trial on fibrinogen in the initial resuscitation of severe trauma (FiiRST) was conducted to evaluate TIC and associated responses to fibrinogen replacement.

STUDY DESIGN AND METHODS

We conducted a retrospective evaluation of TIC in 45 FiiRST trial patients based on rotational thromboelastometry (ROTEM), international normalized ratio (INR), and biomarkers for hemostasis and endotheliopathy. Whole blood was analyzed by ROTEM. Plasma was analyzed for INR and biomarkers.

RESULTS

Overall, 19.0% and 30.0% of the FiiRST trial patients were coagulopathic on admission defined by EXTEM maximum clot firmness out of the range of 40-71 mm and INR >1.2, respectively. The FiiRST patients showed lower fibrinogen, factor II and V levels, protein C and antiplasmin activities, higher activated protein C, tissue plasminogen activator, d-dimer, and thrombomodulin concentrations at admission than healthy controls. Most of the biomarkers changed their activities during 48-h hospitalization, but were at abnormal levels even 48-h after admission. The fibrinogen treatment reduced hypofibrinogenemia and increased factor XIII level, but had no significant effects on other biomarkers levels. Limited development of endotheliopathy was indicated by syndean-1, thrombomodulin, and sE-selectin.

CONCLUSIONS

About 19%-30% of the trauma patients in the FiiRST trial were coagulopathic on hospital admission depending on the definition of TIC. Analyses of the TIC biomarkers demonstrated that hemostasis would not return to normal after 48-h hospitalization, and fibrinogen replacement improved hypofibrinogenemia.

Basic principles of viscoelastic testing

BACKGROUND

Viscoelastic testing is a method of hemostatic analysis that provides a real-time, holistic view of ex vivo clotting. It allows for examination of both cellular and plasma protein contributions to clotting including platelet number and function, fibrin(ogen) function, and coagulation factor function. The method assesses physical clot properties during the transition of blood from a liquid to a gel state, either by measurement of clot shear modulus using physical force transduction or by measurement of clot resonance frequency using sonometric interrogation. Results are reported in a live trace, with different trace parameters reflecting different contributors to hemostasis. These reported parameters vary between testing platforms.

RESULTS

In the United States, there are several commonly used Food and Drug Administration (FDA)-approved viscoelastic instruments available on the market. Those instruments that use sonometric clot assessment are more recently available and allow for improved portability for use near the patient's bedside. These instruments generally feature different reagent kits that allow more specific interrogation of different hemostatic pathways. Viscoelastic testing can predict the results of traditional plasma-based coagulation assays and has the added benefit of detecting hypercoagulability and severe hyperfibrinolysis. Implementation of viscoelastic testing in many clinical settings is becoming widespread and has proven to be efficacious in reducing blood transfusion rates in many settings. An impact on overall mortality and morbidity has not yet been demonstrated.

CONCLUSION

This article provides a narrative review of the basic principles of viscoelastic testing, including the science and technology behind the method, as well as currently available testing platforms and reagents.

Prehospital evaluation and detection of induced coagulopathy in trauma: The PREDICT study

BACKGROUND

Hemorrhage with trauma-induced coagulopathy (TIC) and hyperfibrinolysis (HF) increases the mortality risk after severe trauma. While TIC at hospital admission is well studied, little is known about coagulopathy at the incident site. The aim of the study was to investigate coagulation disorders already present on scene.

METHODS

In a prospective single-center observational study, blood samples of trauma patients obtained before and at hospital admission were analyzed. Data on rotational thromboelastometry, blood gas analysis, prehospital treatment, injury severity, in-hospital blood transfusions, and mortality were investigated according to the presence of coagulation disorders at the incident site. The patients were divided into three groups according to the presence of coagulation disorders (no coagulopathy, TIC, TIC with HF). In a subgroup analysis, patients with a Trauma-Induced Coagulopathy Clinical Score (TICCS) of ≥10 were investigated.

RESULTS

Between August 2015 and February 2018, 148 patients were enrolled in the study. The mean Injury Severity Score was 22.1, and overall mortality was 7.4%. Trauma-induced coagulopathy and HF were already detectable at the incident site in 18.2% and 6.1%, respectively. Patients with HF had significantly altered circulation parameters with significant changes in pH, hemoglobin, lactate, and base excess at the incident site. In patients with TICCS of ≥10 (14.2%), TIC was detected in 47.6% of the cases and HF in 28.6%. Furthermore, in these patients, blood gas parameters significantly changed and the need for blood transfusion and mortality.

CONCLUSION

Trauma-induced coagulopathy and HF can be detected in severely injured patients even before medical treatment is started. Furthermore, in patients with HF and TICCS of ≥10, blood gas parameters were significantly changed at the incident site.

LEVEL OF EVIDENCE

Prognostic study, level III.

Fibrinolytic shutdown diagnosed with rotational thromboelastometry represents a moderate form of coagulopathy associated with transfusion requirement and mortality: A retrospective analysis

BACKGROUND

Viscoelastic techniques have made it possible to describe specific fibrinolytic phenotypes (physiological, hyperfibrinolysis and shutdown) and to establish a relationship of these phenotypes with outcome. However, there remains a debate as to whether shutdown is a state of hypercoagulability or rather a coagulopathy with moderate fibrinolysis and fibrinogen consumption.

OBJECTIVES

Our objectives were to describe the relationship between fibrinolytic phenotypes and outcomes, and to report the effects of tranexamic acid (TXA) administration.

DESIGN

This was a retrospective analysis of prospectively acquired data from a trauma registry.

SETTING

An academic level 1 trauma centre in the Lyon Region, from March 2011 to December 2016.

PATIENTS

We included all injured patients who had a rotational thromboelastometry analysis at admission. Fibrinolytic phenotypes were determined according to the maximum lysis: shutdown less than 3%, physiological 3 to 15%, hyperfibrinolysis more than 15%.

MAIN OUTCOME MEASURE

Mortality at 24 h and at hospital discharge.

RESULTS

During the study period, 473 patients were included with the following phenotypes: physiological (344 patients, 73%), shutdown (107 patients, 23%) and hyperfibrinolysis (22 patients, 5%). There was an increase in injury severity, prothrombin time ratio, fibrin degradation products and transfusion requirements from the physiological to the shutdown and hyperfibrinolysis phenotypes. Prehospital TXA administration increased the rate of shutdown and decreased the maximum lysis value at admission. After adjustment, multivariate analysis showed that fibrinolytic phenotypes, but not TXA, were independently associated with an increased risk of early death and death before hospital discharge: shutdown [odds ratio (95% confidence interval)] 2.4 (1.2 to 4.8) and hyperfibrinolysis 67.9 (7.4 to 624.2).

CONCLUSION

The results of the current study suggest that shutdown, which is associated with injury severity and mortality, probably reflects a moderate form of coagulopathy and fibrinolysis rather than a hypercoagulopathy. Therefore, the observation of shutdown fibrinolysis on thromboelastography/rotational thromboelastometry should not lead to withholding but rather to the administration of TXA.

Effect of emergency department fibrinogen testing on survival of trauma patients receiving blood transfusions

: Fibrinogen is the first clotting factor to reach critically low levels during blood loss and its depletion is associated with coagulopathy, increased blood loss, transfusion requirements and mortality after trauma. However, direct measurements of fibrinogen concentration or function are not included in many Emergency Department (ED) trauma laboratory testing protocols. We hypothesized that including a test of fibrinogen concentration in the ED would be associated with increased survival for trauma patients requiring blood transfusions.To test this hypothesis, we performed a single-centre retrospective study of the effect of a resulted fibrinogen concentration measurement performed in the ED on survival of trauma patients receiving blood transfusions within the first 4 h of their hospital arrival. Multivariate logistic regression was used test the effect of a fibrinogen test on hospital survival after adjusting for the influence of INR, injury severity, lowest recorded blood pressure and blood transfusion intensity defined as the number of red blood cell units transfused in the first 4 h or care.Of 11 404 trauma registry individuals from 2016 to 2017, 843 (7.4%) received any blood transfusions within the first 4 h of ED care, of whom 635 (75.3%) had a documented fibrinogen concentration ordered and resulted. Multivariate logistic regression for hospital survival demonstrated a significant interaction effect between the presence of a fibrinogen test and transfusion intensity (Whole Model P < 0.0001, Interaction P = 0.035). Repeat analysis after stratifying for those individuals receiving more than 4 units of red blood cell units within 4 h of care found that the presence of a fibrinogen test was independently associated with survival only for those receiving more than 4 units [FIB test odds ratio for survival = 3.5 (1.0, 10.8), P = 0.03].Fibrinogen testing in the ED may be a valuable addition to resuscitation of the trauma patient receiving significant blood transfusions.

Trauma-Induced Coagulopathy: Overview of an Emerging Medical Problem from Pathophysiology to Outcomes

Coagulopathy induced by major trauma is common, affecting approximately one-third of patients after trauma. It develops independently of iatrogenic, hypothermic, and dilutive causes (such as iatrogenic cause in case of fluid administration), which instead have a pejorative aspect on coagulopathy. Notwithstanding the continuous research conducted over the past decade on Trauma-Induced Coagulopathy (TIC), it remains a life-threatening condition with a significant impact on trauma mortality. We reviewed the current evidence regarding TIC diagnosis and pathophysiological mechanisms and summarized the different iterations of optimal TIC management strategies among which product resuscitation, potential drug administrations, and hemostatis-focused approaches. We have identified areas of ongoing investigation and controversy in TIC management.

Measuring Fibrinolysis

Physiological fibrinolysis under normal conditions progresses slowly, in contrast to coagulation which is triggered rapidly to stop bleeding and defend against microbial invasion. Methods to detect fibrinolysis abnormalities are less simple and poorly standardized compared with common coagulation tests. Fibrinolysis can be accelerated by preparing euglobulin from plasma to reduce endogenous inhibitors, or by adding plasminogen activators to normal plasma. However, these manipulations complicate interpretation of results and diagnosis of a "fibrinolysis deficit." Many observational studies on antigen levels of fibrinolysis inhibitors, plasminogen activator inhibitor 1 or thrombin-activatable fibrinolysis inhibitor, zymogen or active enzyme have been published. However, conclusions are mixed and there are clear problems with harmonization of results. Viscoelastic methods have the advantage of being rapid and are used as point-of-care tests. They also work with whole blood, allowing the contribution of platelets to be explored. However, there are no agreed protocols for applying viscoelastic methods in acute care for the diagnosis of hyperfibrinolysis or to direct therapy. The emergence of SARS-CoV-2 and the dangers of associated coagulopathy provide new challenges. A common finding in hospitalized patients is high levels of D-dimer fibrin breakdown products, indicative of ongoing fibrinolysis. Well-established problems with D-dimer testing standardization signal that we should be cautious in using results from such tests as prognostic indicators or to target therapies.

Trimester-specific thromboelastic values and coagulation activation markers in pregnancy compared across trimesters and compared to the nonpregnant state

INTRODUCTION

Rotational thromboelastometry (ROTEM) rapidly identifies deficits underlying coagulopathy during massive hemorrhage. Prompt coagulopathy correction is balanced with the risk of blood product overutilization, making the ability to quickly target therapy highly desirable. However, data about ROTEM reference ranges in pregnancy are limited. We hypothesized that ROTEM parameters change across trimesters of pregnancy and differ from the nonpregnant state. Also, we sought to identify which hemostatic test best predicts coagulation activation during pregnancy.

METHODS

A prospective cohort study in healthy pregnant patients in the first (n = 34), second (n = 34), and third trimesters (n = 41) against healthy, nonpregnant controls (n = 33) was performed. Citrated blood was collected, and ROTEM, complete blood count, and plasma-based assays of coagulation were performed. Mean ± SD or median [IQR] were compared across trimesters and between each trimester against the nonpregnant state. ROTEM parameters vs. plasma-based assays were also compared.

RESULTS

Maximum clot firmness and A10 in FIBTEM correlated strongly with fibrinogen level. INTEM and EXTEM values demonstrated only weak to modest correlation with corresponding tests using plasma assays. Thrombin antithrombin complex (TAT) increased from the first trimester onward, whereas other coagulation activation markers did not show difference compared with control group.

CONCLUSION

Rotational thromboelastometry parameters differ variably across trimesters of pregnancy and compared with the nonpregnant state. The development and use of pregnancy-specific values are critical to the proper clinical interpretation of ROTEM in women with serious hemorrhage during different stages in pregnancy. TAT was the earliest laboratory marker for coagulation activation among others.

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.

Serial Evaluation of Haemostasis Following Acute Trauma Using Rotational Thromboelastometry in Dogs

OBJECTIVE

 The aim of this study was to describe the coagulation status of traumatized dogs over the first 24 hours after admission.

STUDY DESIGN

 In 33 dogs presenting within 6 hours after trauma blood was sampled for rotational thromboelastometry (ROTEM), thrombocyte number and venous blood gas analysis at presentation and 6 and 24 hours thereafter. At each time point, dogs were defined as hypo-, normo- or hypercoagulable based on extrinsic, intrinsic and fibrinogen ROTEM profiles.

RESULTS

 Significantly more dogs (11/33) presented hypocoagulable compared with 6 hours (p = 0.046) and 24 hours (p = 0.008) thereafter and none presented hypercoagulable. Significantly more dogs were hypercoagulable (6/23, p = 0.014) and no dog was hypocoagulable at 24 hours compared with presentation. All evaluated ROTEM parameters except maximum lysis were significantly more hypocoagulable at presentation compared with 24 hours thereafter.

CONCLUSION

 Hypocoagulability is more common in acutely traumatized dogs than previously described. Dogs were hypo- or normocoagulable at presentation and the coagulation status changed to normo- or hypercoagulability over the first 24 hours. Clotting times, clot formation and clot firmness but not clot lysis were significantly altered at presentation compared with 24 hours and fibrinogen concentration or function may play an important role in the dynamic change of coagulation state over time.

New Uses for Thromboelastography and Other Forms of Viscoelastic Monitoring in the Emergency Department: A Narrative Review

Patients frequently visit the emergency department with conditions that place them at risk of worse outcomes when accompanied by coagulopathy. Routine tests of coagulation-prothrombin time, partial thromboplastin time, platelets, and fibrinogen-have shortcomings that limit their use in providing emergency care. One alternative is to investigate coagulation disturbance with viscoelastic monitoring (VEM), a coagulation test that measures the timing and strength of blood clot development in real time. VEM is widely used and studied in cardiac surgery, liver transplant surgery, anesthesia, and trauma. In this article, we review the technique of VEM and the biologic rationale of using it in addition to routine tests of coagulation in emergency clinical situations. Then, we review the evidence (or lack thereof) for using VEM in the diagnosis and treatment of specific conditions. Finally, we describe the limitations of the test and future directions for clinical use and research in emergency medicine.

Is major burn injury associated with coagulopathy? The value of thrombelastometry in the detection of coagulopathy in major burn injury: A prospective observational study

BACKGRUND

The coagulation status of burn patients is generally impaired and is a major factor of the deteriorating burn patients' overall situation. In trauma and other patient groups, the differential diagnosis of coagulation impairment has been largely improved by the use of rotational thromboelastometry (ROTEM®). The aim of this prospective observational study was the differentiated observation of coagulopathy in severely burned patients using standard parameters and ROTEM® thrombelastometry during the relevant stages of burn disease.

PATIENTS AND METHODS

Twelve patients that sustained at least 20% third degree burns of total body surface area (TBSA) were included in the study. Standard and ROTEM® coagulation analyses were performed on admission and then twice daily during the first 14 days following burn trauma.

RESULTS

Although the initial assessment of DIC was similar for both standard labs and ROTEM® measurements, more patients were detected to be in a state of worsening coagulation status for a longer time in ROTEM® than in standard measurements. In addition, one patient was rated in to be in decompensated DIC for 3 days according to ROTEM® measurements, while no patient was rated to be in a decompensated DIC based on standard parameters.

CONCLUSION

This study points towards a more complex picture and higher occurrence of DIC in burn patients when thrombelastometric measurements like ROTEM® are taken into account in addition to standard coagulation parameters.

Critical Care Society of Southern Africa adult patient blood management guidelines: 2019 Round-table meeting, CCSSA Congress, Durban, 2018

The CCSSA PBM Guidelines have been developed to improve patient blood management in critically ill patients in southern Africa. These consensus recommendations are based on a rigorous process by experts in the field of critical care who are also practicing in South Africa (SA). The process comprised a Delphi process, a round-table meeting (at the CCSSA National Congress, Durban, 2018), and a review of the best available evidence and international guidelines. The guidelines focus on the broader principles of patient blood management and incorporate transfusion medicine (transfusion guidelines), management of anaemia, optimisation of coagulopathy, and administrative and ethical considerations. There are a mix of low-middle and high-income healthcare structures within southern Africa. Blood products are, however, provided by the same not-for-profit non-governmental organisations to both private and public sectors. There are several challenges related to patient blood management in SA due most notably to a high incidence of anaemia, a frequent shortage of blood products, a small donor population, and a healthcare system under financial strain. The rational and equitable use of blood products is important to ensure best care for as many critically ill patients as possible. The summary of the recommendations provides key practice points for the day-to-day management of critically ill patients. A more detailed description of the evidence used to make these recommendations follows in the full clinical guidelines section.

Site-Of-Care Viscoelastic Assay in Major Trauma Improves Outcomes and Is Cost Neutral Compared with Standard Coagulation Tests

Major hemorrhage is often associated with trauma-induced coagulopathy. Targeted blood product replacement could achieve faster hemostasis and reduce mortality. This study aimed to investigate whether thromboelastography (TEG^®) goal-directed transfusion improved blood utilization, reduced mortality, and was cost effective. Data were prospectively collected in a U.K. level 1 trauma center, in patients with major hemorrhage one year pre- and post-implementation of TEG^® 6s Hemostasis Analyzers. Mortality, units of blood products transfused, and costs were compared between groups. Patient demographics in pre-TEG (n = 126) and post-TEG (n = 175) groups were similar. Mortality was significantly lower in the post-TEG group at 24 h (13% vs. 5%; p = 0.006) and at 30 days (25% vs. 11%; p = 0.002), with no difference in the number or ratio of blood products transfused. Cost of blood products transfused was comparable, with the exception of platelets (average £38 higher post-TEG). Blood product wastage was significantly lower in the post-TEG group (1.8 ± 2.1 vs. 1.1 ± 2.0; p = 0.002). No statistically significant difference in cost was observed between the two groups (£753 ± 651 pre-TEG; £830 ± 847 post-TEG; p = 0.41). These results demonstrate TEG 6s-driven resuscitation algorithms are associated with reduced mortality, reduced blood product wastage, and are cost neutral compared to standard coagulation tests.

Hypercoagulability After Resection of Thoracic Malignancy: A Prospective Evaluation

BACKGROUND

Rates of venous thromboembolism are increased in thoracic malignancy; however, coagulation patterns are not established. We hypothesize that patients with esophageal and lung malignancy have similar hypercoagulable pre- and postoperative profiles as defined by rotational thromboelastometry (ROTEM).

METHODS

Prospective study was conducted in 47 patients with esophageal and lung cancer undergoing surgical resection. ROTEM evaluated pre/postoperative coagulation status.

RESULTS

Patients with thoracic malignancy were hypercoagulable by ROTEM, but not by conventional coagulation tests. Preoperative hypercoagulability was higher in lung versus esophageal cancer (64 vs. 16%, p = 0.001). Lung cancer patients that were hypercoagulable preoperatively demonstrated decreased maximum clot firmness (MCF) (p = 0.044) and increased clot time (p = 0.049) after surgical resection, suggesting reversal of hypercoagulability. Resection of esophageal cancer increased hypercoagulability (16 vs. 56%, p = 0.002) via elevated MCF (reflecting platelet activity). Hypercoagulability remained at follow-up clinic for both lung and esophageal cancer patients.

CONCLUSIONS

Hypercoagulability in patients with lung malignancies reversed following complete surgical resection, whereas hypercoagulability occurred only postoperatively in those with esophageal malignancies. In both, hypercoagulability was associated with fibrin and platelet function.

To Clot or Not: HELLP Syndrome and Disseminated Intravascular Coagulation in an Eclamptic Patient with Intrauterine Fetal Demise

A 39-year-old G2P1001 female presented from an outside hospital following an eclamptic seizure in the setting of HELLP syndrome. This condition was complicated by intrauterine fetal demise and disseminated intravascular coagulation, which required an emergent cesarean section. We report the work-up and intraoperative and postoperative management of this complex patient with multiple medical needs. We focus on the hemostatic abnormalities in this patient and describe how our management would differ from that of a similar, nonpregnant patient.

Serum Procalcitonin Level Predicts Acute Kidney Injury After Traumatic Brain Injury

BACKGROUND

A common non-neurologic complication after traumatic brain injury (TBI), acute kidney injury (AKI) is a risk factor of mortality. Some studies confirmed the predictive value of procalcitonin (PCT) on AKI in several clinical settings. We designed this study to explore the predictive value of PCT on AKI after TBI.

METHODS

We retrospectively enrolled patients with TBI admitted to our hospital from February 2015 to June 2019. Multivariate logistic regression analysis was performed to find the risk factors of AKI and construct a predictive model for AKI. Receiver operating characteristics curves were drawn to compare the predictive value of PCT and the constructed model.

RESULTS

A total of 214 patients were included in this study. The incidence of AKI after TBI was 25.70% in this study. Compared with the non-AKI group, the AKI group had higher age (P = 0.031), lower Glasgow Coma Scale (P < 0.001), and higher incidence of coagulopathy (P < 0.001) and shock (P < 0.001). Moreover, patients complicated with AKI had higher in-hospital mortality (P < 0.001) and worse 90-day outcome (P < 0.001). Multivariate logistic regression analysis indicated that age (P = 0.033), PCT (P = 0.002), serum chlorine (P = 0.011), and creatinine (P < 0.001) were independent risk factors of AKI. We constructed a predictive model using these 4 risk factors. The area under receiver operating characteristics curves of the predictive model was 0.928, which was significantly higher than that of a single PCT value (area under receiver operating characteristics curves = 0.833) (Z = 2.395, P < 0.05).

CONCLUSIONS

PCT is valuable in predicting AKI after TBI. To avoid AKI after TBI, physicians can adjust treatment strategies according to the level of PCT.

Trauma Coagulopathy and Its Outcomes

Background and Objectives: Trauma coagulopathy begins at the moment of trauma. This study investigated whether coagulopathy upon arrival in the emergency room (ER) is correlated with increased hemotransfusion requirement, more hemodynamic instability, more severe anatomical damage, a greater need for hospitalization, and hospitalization in the intensive care unit (ICU). We also analyzed whether trauma coagulopathy is correlated with unfavorable indices, such as acidemia, lactate increase, and base excess (BE) increase. Material and Methods: We conducted a prospective, monocentric, observational study of all patients (n = 503) referred to the Department of Emergency and Acceptance, IRCCS Fondazione Policlinico San Matteo, Pavia, for major trauma from 1 January 2018 to 30 January 2019. Results: Of the 503 patients, 204 had trauma coagulopathy (group 1), whereas 299 patients (group 2) did not. Group 1 had a higher hemotransfusion rate than group 2. In group 1, 15% of patients showed hemodynamic instability compared with only 8% of group 2. The shock index (SI) distribution was worse in group 1 than in group 2. Group 1 was more often hypotensive, tachycardic, and with low oxygen saturation, and had a more severe injury severity score than group 2. In addition, 47% of group 1 had three or more body districts involved compared with 23% of group 2. The hospitalization rate was higher in group 1 than in group 2 (76% vs. 58%). The length of hospitalization was >10 days for 45% of group 1 compared with 28% of group 2. The hospitalization rate in the ICU was higher in group 1 than in group 2 (22% vs. 14.8%). The average duration of ICU hospitalization was longer in group 1 than in group 2 (12.5 vs. 9.78 days). Mortality was higher in group 1 than in group 2 (3.92% vs. 0.98%). Group 1 more often had acidemia and high lactates than group 2. Group 1 also more often had BE <−6. Conclusions: Trauma coagulopathy patients, upon arrival in the ER, have greater hemotransfusion (p = 0.016) requirements and need hospitalization (p = 0.032) more frequently than patients without trauma coagulopathy. Trauma coagulopathy seems to be more present in patients with a higher injury severity score (ISS) (p = 0.000) and a greater number of anatomical districts involved (p = 0.000). Head trauma (p = 0.000) and abdominal trauma (p = 0.057) seem related to the development of trauma coagulopathy. Males seem more exposed than females in developing trauma coagulopathy (p = 0.018). Upon arrival in the ER, the presence of tachycardia or alteration of SI and its derivatives can allow early detection of patients with trauma coagulopathy.

Rotational thromboelastometry-guided transfusion during lumbar pedicle subtraction osteotomy for adult spinal deformity: preliminary findings from a matched cohort study

OBJECTIVESignificant blood loss and coagulopathy are often encountered during adult spinal deformity (ASD) surgery, and the optimal intraoperative transfusion algorithm is debatable. Rotational thromboelastometry (ROTEM), a functional viscoelastometric method for real-time hemostasis testing, may allow early identification of coagulopathy and improve transfusion practices. The objective of this study was to investigate the effect of ROTEM-guided blood product management on perioperative blood loss and transfusion requirements in ASD patients undergoing correction with pedicle subtraction osteotomy (PSO).METHODSThe authors retrospectively reviewed patients with ASD who underwent single-level lumbar PSO at the University of Virginia Health System. All patients who received ROTEM-guided blood product transfusion between 2015 and 2017 were matched in a 1:1 ratio to a historical cohort treated using conventional laboratory testing (control group). Co-primary outcomes were intraoperative estimated blood loss (EBL) and total blood product transfusion volume. Secondary outcomes were perioperative transfusion requirements and postoperative subfascial drain output.RESULTSThe matched groups (ROTEM and control) comprised 17 patients each. Comparison of matched group baseline characteristics demonstrated differences in female sex and total intraoperative dose of intravenous tranexamic acid (TXA). Although EBL was comparable between ROTEM versus control (3200.00 ± 2106.24 ml vs 3874.12 ± 2224.22 ml, p = 0.36), there was a small to medium effect size (Cohen's d = 0.31) on EBL reduction with ROTEM. The ROTEM group had less total blood product transfusion volume (1624.18 ± 1774.79 ml vs 2810.88 ± 1847.46 ml, p = 0.02), and the effect size was medium to large (Cohen's d = 0.66). This difference was no longer significant after adjusting for TXA (β = -0.18, 95% confidence interval [CI] -1995.78 to 671.64, p = 0.32). More cryoprecipitate and less fresh frozen plasma (FFP) were transfused in the ROTEM group patients (cryoprecipitate units: 1.24 ± 1.20 vs 0.53 ± 1.01, p = 0.03; FFP volume: 119.76 ± 230.82 ml vs 673.06 ± 627.08 ml, p < 0.01), and this remained significant after adjusting for TXA (cryoprecipitate units: β = 0.39, 95% CI 0.05 to 1.73, p = 0.04; FFP volume: β = -0.41, 95% CI -772.55 to -76.30, p = 0.02). Drain output was lower in the ROTEM group and remained significant after adjusting for TXA.CONCLUSIONSFor ASD patients treated using lumbar PSO, more cryoprecipitate and less FFP were transfused in the ROTEM group compared to the control group. These preliminary findings suggest ROTEM-guided therapy may allow early identification of hypofibrinogenemia, and aggressive management of this may reduce blood loss and total blood product transfusion volume. Additional prospective studies of larger cohorts are warranted to identify the appropriate subset of ASD patients who may benefit from intraoperative ROTEM analysis.

Viscoelastic haemostatic assays in aeromedical transport

OBJECTIVE

To assess the feasibility of using rotational thromboelastometry (ROTEM®)-sigma and thromboelastography (TEG®)-6s viscoelastic point-of-care assays during rotary wing aeromedical transport, and to determine the reliability of the results obtained.

METHODS

A single centre, prospective, observational, non-interventional feasibility study performed at Gold Coast University Hospital intensive care unit, and in a LifeFlight Retrieval Medicine operated Leonardo AW139 helicopter. Blood was collected from eight healthy volunteers on 18 April 2019 and all testing was performed on that day. Functions measured were ROTEM-sigma extrinsically activated thromboelastometry (EXTEM) clotting time (CT), EXTEM amplitude at 5 min after CT (A5) and fibrin-based extrinsically activated thromboelastometry (FIBTEM) A5, and TEG-6s Kaolin (CK) reaction time (R), functional fibrinogen (CFF) maximal amplitude (MA) and CFF amplitude at 10 min after R (A10). Differences between the results obtained in the helicopter and control results at Gold Coast University Hospital during flight and after flight, and also differences in control results over time up to 3 h were analysed.

RESULTS

During flight both the ROTEM-sigma and TEG-6s devices failed to give reliable results. Post flight, the helicopter and control samples correlated well. Repeat testing of control samples at 1 and 3 h also revealed good correlation over time.

CONCLUSION

It is feasible to reliably run tests on both the ROTEM-sigma and TEG-6s after the devices have been flown in a rotary wing aircraft. However, testing cannot be performed while in flight conditions. It is also possible to run blood samples collected up to 3 h prior and acquire results which correlate well with initial testing.

Clinical controversies in anticoagulation monitoring and antithrombin supplementation for ECMO

During extracorporeal membrane oxygenation (ECMO), a delicate balance is required to titrate systemic anticoagulation to prevent thrombotic complications within the circuit and prevent bleeding in the patient. Despite focused efforts to achieve this balance, the frequency of both thrombotic and bleeding events remains high. Anticoagulation is complicated to manage in this population due to the complexities of the hemostatic system that are compounded by age-related developmental hemostatic changes, variable effects of the etiology of critical illness on hemostasis, and blood-circuit interaction. Lack of high-quality data to guide anticoagulation management in ECMO patients results in marked practice variability among centers. One aspect of anticoagulation therapy that is particularly challenging is the use of antithrombin (AT) supplementation for heparin resistance. This is especially controversial in the neonatal and pediatric population due to the baseline higher risk of bleeding in this cohort. The indication for AT supplementation is further compounded by the potential inaccuracy of the diagnosis of heparin resistance based on the standard laboratory parameters used to assess heparin effect. With concerns regarding the adverse impact of bleeding and thrombosis, clinicians and institutions are faced with making difficult, real-time decisions aimed at optimizing anticoagulation in this setting. In this clinically focused review, the authors discuss the complexities of anticoagulation monitoring and therapeutic intervention for patients on ECMO and examine the challenges surrounding AT supplementation given both the historical and current perspectives summarized in the literature on these topics.

Early Identification of Trauma-induced Coagulopathy: Development and Validation of a Multivariable Risk Prediction Model

OBJECTIVE

The aim of this study was to develop and validate a risk prediction tool for trauma-induced coagulopathy (TIC), to support early therapeutic decision-making.

BACKGROUND

TIC exacerbates hemorrhage and is associated with higher morbidity and mortality. Early and aggressive treatment of TIC improves outcome. However, injured patients that develop TIC can be difficult to identify, which may compromise effective treatment.

METHODS

A Bayesian Network (BN) prediction model was developed using domain knowledge of the causal mechanisms of TIC, and trained using data from 600 patients recruited into the Activation of Coagulation and Inflammation in Trauma (ACIT) study. Performance (discrimination, calibration, and accuracy) was tested using 10-fold cross-validation and externally validated on data from new patients recruited at 3 trauma centers.

RESULTS

Rates of TIC in the derivation and validation cohorts were 11.8% and 11.0%, respectively. Patients who developed TIC were significantly more likely to die (54.0% vs 5.5%, P < 0.0001), require a massive blood transfusion (43.5% vs 1.1%, P < 0.0001), or require damage control surgery (55.8% vs 3.4%, P < 0.0001), than those with normal coagulation. In the development dataset, the 14-predictor BN accurately predicted this high-risk patient group: area under the receiver operating characteristic curve (AUROC) 0.93, calibration slope (CS) 0.96, brier score (BS) 0.06, and brier skill score (BSS) 0.40. The model maintained excellent performance in the validation population: AUROC 0.95, CS 1.22, BS 0.05, and BSS 0.46.

CONCLUSIONS

A BN (http://www.traumamodels.com) can accurately predict the risk of TIC in an individual patient from standard admission clinical variables. This information may support early, accurate, and efficient activation of hemostatic resuscitation protocols.

Clinical utility of rotational thromboelastometry in detecting hemostatic disorders

Hemostasis represents an equilibrium between procoagulant and anticoagulant processes, but once this balance is shifted to one side, it leads to coagulopathy presented by pathological bleeding or thrombosis. Many conditions could cause coagulopathy. The most common are sepsis, severe traumas and malignancies. Widely used conventional coagulation tests (CCTs), focused only on clot initiation, are primary used to detect hypocoagulability. Viscoelastographic tests (VET), like rotational thromboelastometry (ROTEM), can detect problems in different stages of coagulation, from initiation thought clot elongation and propagation, to the clot lysis and might reveal both, hypercoagulability and hypocoagulability. Rotational thromboelastometry have gained popularity in the care of patients with TIC, as a tool to guide transfusion support. Nowadays it is widely used in other medical specialties, as well. Several studies in septic patients pointed out hypocoagulable ROTEM pattern as a predictor of poor prognosis. Additionally, there is great interest of ROTEM usage in malignancies, although limited research is currently available. It suggests ROTEM have the ability to identify a patient in high risk of thrombosis. Further investigation trough randomized studies is needed to confirm ROTEM utility and to help in making a consensus about its use in different medical occasions.

Technology Advancements in Blood Coagulation Measurements for Point-of-Care Diagnostic Testing

In recent years, blood coagulation monitoring has become crucial to diagnosing causes of hemorrhages, developing anticoagulant drugs, assessing bleeding risk in extensive surgery procedures and dialysis, and investigating the efficacy of hemostatic therapies. In this regard, advanced technologies such as microfluidics, fluorescent microscopy, electrochemical sensing, photoacoustic detection, and micro/nano electromechanical systems (MEMS/NEMS) have been employed to develop highly accurate, robust, and cost-effective point of care (POC) devices. These devices measure electrochemical, optical, and mechanical parameters of clotting blood. Which can be correlated to light transmission/scattering, electrical impedance, and viscoelastic properties. In this regard, this paper discusses the working principles of blood coagulation monitoring, physical and sensing parameters in different technologies. In addition, we discussed the recent progress in developing nanomaterials for blood coagulation detection and treatments which opens up new area of controlling and monitoring of coagulation at the same time in the future. Moreover, commercial products, future trends/challenges in blood coagulation monitoring including novel anticoagulant therapies, multiplexed sensing platforms, and the application of artificial intelligence in diagnosis and monitoring have been included.

Viscoelastic Signals for Optimal Resuscitation in Trauma: Kaolin Thrombelastography Cutoffs for Diagnosing Hypofibrinogenemia (VISOR Study)

BACKGROUND

Acute traumatic coagulopathy is common in trauma patients. Prompt diagnosis of hypofibrinogenemia allows for early treatment with cryoprecipitate or fibrinogen concentrate. At present, optimal cutoffs for diagnosing hypofibrinogenemia with kaolin thrombelastography (TEG) have not been established. We hypothesized that kaolin kaolin-TEG parameters, such as kinetic time (K-time), α-angle, and maximum amplitude (MA), would accurately diagnose hypofibrinogenemia (fibrinogen <200 mg/dL) and severe hypofibrinogenemia (fibrinogen <100 mg/dL).

METHODS

Adult trauma patients (injury severity score >15) presenting to our trauma center between October 2015 and October 2017 were identified retrospectively. All patients had a traditional plasma fibrinogen measurement and kaolin-TEG performed within 15 minutes of each other and within 1 hour of admission. Some patients had additional measurements after. Receiver operating characteristic (ROC) curve analysis was performed to evaluate whether K-time, α-angle, and MA could diagnose hypofibrinogenemia and severe hypofibrinogenemia. Area under the ROC curve (AUROC) was calculated for each TEG parameter with a bootstrapped 99% confidence interval (CI). Further, ROC analysis was used to estimate ideal cutoffs for diagnosing hypofibrinogenemia and severe hypofibrinogenemia by maximizing sensitivity and specificity. In addition, likelihood ratios were also calculated for different TEG variable cutoffs to diagnose hypofibrinogenemia and severe hypofibrinogenemia.

RESULTS

Seven hundred twenty-two pairs of TEGs and traditional plasma fibrinogen measurements were performed in 623 patients with 99 patients having additional pairs of tests after the first hour. MA (AUROC = 0.84) and K-time (AUROC = 0.83) better diagnosed hypofibrinogenemia than α-angle (AUROC = 0.8; P = .03 and P < .001 for AUROC comparisons, respectively). AUROCs statistically improved for each parameter when severe hypofibrinogenemia was modeled as the outcome (P < .001). No differences were found between parameters for diagnosing severe hypofibrinogenemia (P > .05 for all comparisons). The estimated optimal cutoffs for diagnosing hypofibrinogenemia were 1.5 minutes for K-time (95% CI, 1.4-1.6), 70.0° for α-angle (95% CI, 69.8-71.0), and 60.9 mm for MA (95% CI, 59.2-61.8). The estimated optimal cutoffs for diagnosing severe hypofibrinogenemia were 2.4 minutes for K-time (95% CI, 1.7-2.8), 60.6° for α-angle (95% CI, 57.2-67.3), and 51.2 mm for MA (95% CI, 49.0-56.2). Currently recommended K-time and α-angle cutoffs from the American College of Surgeons had low sensitivity for diagnosing hypofibrinogenemia (3%-29%), but sensitivity improved to 74% when using optimal cutoffs.

CONCLUSIONS

Kaolin-TEG parameters can accurately diagnose hypofibrinogenemia and severe hypofibrinogenemia in trauma patients. Currently recommended cutoffs for the treatment of hypofibrinogenemia are skewed toward high specificity and low sensitivity. Many patients are likely to be undertreated for hypofibrinogenemia using current national guidelines.

Timing of major fracture care in polytrauma patients - An update on principles, parameters and strategies for 2020

OBJECTIVES

Sustained changes in resuscitation and transfusion management have been observed since the turn of the millennium, along with an ongoing discussion of surgical management strategies. The aims of this study are threefold: a) to evaluate the objective changes in resuscitation and mass transfusion protocols undertaken in major level I trauma centers; b) to summarize the improvements in diagnostic options for early risk profiling in multiply injured patients and c) to assess the improvements in surgical treatment for acute major fractures in the multiply injured patient.

METHODS

I. A systematic review of the literature (comprehensive search of the MEDLINE, Embase, PubMed, and Cochrane Central Register of Controlled Trials databases) and a concomitant data base (from a single Level I center) analysis were performed. Two authors independently extracted data using a pre-designed form. A pooled analysis was performed to determine the changes in the management of polytraumatized patients after the change of the millennium. II. A data base from a level I trauma center was utilized to test any effects of treatment changes on outcome.

INCLUSION CRITERIA

adult patients, ISS > 16, admission < less than 24 h post trauma. Exclusion: Oncological diseases, genetic disorders that affect the musculoskeletal system. Parameters evaluated were mortality, ICU stay, ICU complications (Sepsis, Pneumonia, Multiple organ failure).

RESULTS

I. From the electronic databases, 5141 articles were deemed to be relevant. 169 articles met the inclusion criteria and a manual review of reference lists of key articles identified an additional 22 articles. II. Out of 3668 patients, 2694 (73.4%) were male, the mean ISS was 28.2 (SD 15.1), mean NISS was 37.2 points (SD 17.4 points) and the average length of stay was 17.0 days (SD 18.7 days) with a mean length of ICU stay of 8.2 days (SD 10.5 days), and a mean ventilation time of 5.1 days (SD 8.1 days). Both surgical management and nonsurgical strategies have changed over time. Damage control resuscitation, dynamic analyses of coagulopathy and lactate clearance proved to sharpen the view of the worsening trauma patient and facilitated the prevention of further complications. The subsequent surgical care has become safer and more balanced, avoiding overzealous initial surgeries, while performing early fixation, when patients are physiologically stable or rapidly improving. Severe chest trauma and soft tissue injuries require further evaluation.

CONCLUSIONS

Multiple changes in management (resuscitation, transfusion protocols and balanced surgical care) have taken place. Moreover, improvement in mortality rates and complications associated with several factors were also observed. These findings support the view that the management of polytrauma patients has been substantially improved over the past 3 decades.

Successful ROTEM-guided transfusion therapy in a case of rural paediatric trauma

Massive transfusion therapy in severe paediatric trauma is a challenge. When this occurs in a rural setting, the potential delays in accessing medical services can lead to worse coagulopathy on presentation. We report successful treatment of a child post-traumatic lower limb amputation where treatment was only initiated 3 hours postinjury due to difficulties in access/retrieval. Rotational thromboelastometry (ROTEM)-guided, goal-directed haemostatic therapy perioperatively utilising a blood product ratio of 2:2:1 units of red blood cell:free frozen plasma:platelet reverted his coagulopathy. This report aims to raise awareness of the utility of ROTEM in paediatric trauma.