Increased blood coagulation is associated with poor neurological outcome in aneurysmal subarachnoid hemorrhage.

BACKGROUND AND PURPOSE: Patients with aneurysmal subarachnoid hemorrhage (aSAH) have demonstrated increased blood coagulation which is thought to contribute to delayed cerebral ischemia (DCI) and to a worse outcome. Therefore, we sought to determine whether this increased blood coagulation, detectable with rotational thromboelastometry (ROTEM), was associated with DCI and neurological outcome. METHODS: We conducted a prospective observational study of 60 consecutive adult aSAH patients. ROTEM's EXTEM and FIBTEM assays and D-dimer were analyzed at admission and post-bleed days (PBDs) 2-3, 4-5, 7-8, and 11-12. ROTEM's clot formation time (CFT) represents the stabilization of the clot, and the maximum clot firmness (MCF) the maximum clot strength. Glasgow Outcome Scale extended (GOSe) at three months determined the neurological outcome. RESULTS: DCI incidence was 41.7%. EXTEM-CFT was significantly shorter in patients with unfavorable neurological outcome (GOSe 1-4) on PBDs 4-5 and 7-8, p < 0.05, respectively. FIBTEM-MCF was significantly higher in patients with unfavorable neurological outcomes on PBD 4-5 (p < 0.05), PBD 7-8 (p < 0.05), and PBD 11-12 (p < 0.05). EXTEM-CFT decreased, and FIBTEM-MCF rose during the study period in all patients. Patients with unfavorable neurological outcome had a higher D-dimer at all studied time points, p < 0.05. No difference was found in the ROTEM parameters or D-dimer when assessing patients with and without DCI. CONCLUSIONS: Patients were in a state of increased blood coagulation after aSAH, with those with unfavorable neurological outcome being more coagulable than those with favorable outcome. However, increased blood coagulation was not associated with DCI. CLINICALTRIALS: gov, NCT03985176.

Trauma-induced coagulopathy: What you need to know.

ABSTRACT: Trauma-induced coagulopathy (TIC) is a global inflammatory state accompanied by coagulation derangements, acidemia, and hypothermia, which occurs after traumatic injury. It occurs in approximately 25% of severely injured patients, and its incidence is directly related to injury severity. The mechanism of TIC is multifaceted; proposed contributing factors include dysregulation of activated protein C, increased tPA, systemic endothelial activation, decreased fibrinogen, clotting factor consumption, and platelet dysfunction. Effects of TIC include systemic inflammation, coagulation derangements, acidemia, and hypothermia. Trauma-induced coagulopathy may be diagnosed by conventional coagulation tests including platelet count, Clauss assay, international normalized ratio, thrombin time, prothrombin time, and activated partial thromboplastin time; viscoelastic hemostatic assays such as thrombelastography and rotational thrombelastography; or a clinical scoring system known as the Trauma Induced Coagulopathy Clinical Score. Preventing TIC begins in the prehospital phase with early hemorrhage control, blood product resuscitation, and tranexamic acid therapy. Early administration of prothrombin complex concentrate is also being studied in the prehospital environment. The mainstays of TIC treatment include hemorrhage control, blood and component transfusions, and correction of abnormalities such as hypocalcemia, acidosis, and hypothermia. LEVEL OF EVIDENCE: Therapeutic/Care Management; Level III.

Analysis of fibrinolytic shutdown in trauma patients with traumatic brain injury.

BACKGROUND: Coagulation profiles following major trauma vary depending on injury pattern and degree of shock. The physiologic mechanisms involved in coagulation function at any given time are varied and remain poorly understood. Thromboelastography (TEG) has been used evaluate coagulation profiles in the trauma population with some reports demonstrating a spectrum of fibrinolysis to fibrinolytic shutdown on initial presentation. The objective of this study was to evaluate the fibrinolytic profile of patients with TBI using thromboelastography (TEG). We hypothesized that patients with TBI would demonstrate low fibrinolytic activity. METHODS: All trauma activations at an ACS-verified level 1 trauma center received a TEG analysis upon arrival from December 2019 to June 2021. A retrospective review of the results and outcomes was conducted, and TBI patients were compared to patients without TBI. Linear regression was used to evaluate the effect of patient and injury factors on fibrinolysis. Hyperfibrinolysis was defined as LY30 â€‹> â€‹7.7%, physiologic fibrinolysis as LY30 0.6-7.7%, and fibrinolytic shutdown as LY30 â€‹< â€‹0.6%. RESULTS: A total of 1369 patients received an admission TEG analysis. Patients with TBI had a significantly higher median ISS (16 vs. 8, p â€‹< â€‹0.001), lower median admission Glasgow Coma Scale (14 vs. 15, p â€‹< â€‹0.001), longer intensive care unit length of stay (3 vs. 2 days, p â€‹< â€‹0.0001), increased ventilator days (216 vs. 183, p â€‹< â€‹0.001), higher mortality (14.6% vs. 5.1%, p â€‹< â€‹0.001), but lower shock index (0.6 vs. 0.7, p â€‹< â€‹0.0001) compared to those without TBI. Median LY30 was found to be decreased in the TBI group (0.1 vs. 0.2, p â€‹= â€‹0.0006). Patients with TBI were found to have a higher rate of fibrinolytic shutdown compared those without TBI (68.7% vs. 63.5%, p â€‹= â€‹0.054). ISS, sex, and shock index were found to be predictive of LY30 on linear regression, but TBI was not (Β: 0.09, SE: 0.277, p â€‹= â€‹0.745). The rate of DVT/PE did not appear to be elevated in patients with TBI (0.8%) and without TBI (1.2%). CONCLUSIONS: Trauma patients with and without TBI were found to have high rates of fibrinolytic shutdown. Although there was a high incidence of fibrinolytic shutdown, it did not appear to have an impact on the rate of thrombotic complications. The clinical significance of these results is unclear and differs significantly from recent reports which demonstrated that TBI is associated with a 25% rate of fibrinolytic shutdown. Further investigation is needed to better define the fibrinolytic pathway in patients with trauma and TBI to develop optimal treatment algorithms.

A Pilot Observational Study Evaluating the Diagnostic Capacity of Rotational Thromboelastometry in Periprosthetic Joint Infections.

BACKGROUND: Periprosthetic joint infections (PJIs) are associated with altered hemostatic dynamics; therefore, coagulation laboratory methods such as rotational thromboelastometry (ROTEM) may be valuable in their diagnosis. The aim of this study was to evaluate the diagnostic role of ROTEM in PJI. METHODS: A diagnostic study was conducted including 65 patients who underwent revision total hip arthroplasty or total knee arthroplasty due to PJI (30 patients) or aseptic loosening (35 patients). Preoperative laboratory evaluation included conventional coagulation studies, inflammatory markers, and ROTEM analysis. These parameters were compared between patients with PJI and patients with aseptic loosening. RESULTS: Several ROTEM parameters differed in the patients with PJI, indicating a higher coagulation potential associated with PJI. Specifically, the development of PJI was associated with higher EXTEM maximum clot firmness (MCF) (odds ratio [OR], 1.12 [95% confidence interval (CI), 1.04 to 1.20]; p = 0.001). Among the ROTEM parameters, EXTEM MCF was found to have the highest diagnostic accuracy for PJI (area under the receiver operating characteristic curve, 0.850; sensitivity, 76.6%; specificity, 91.4%), which was comparable with C-reactive protein (CRP) (p = 0.22) and erythrocyte sedimentation rate (ESR) (p = 0.65), but higher than D-dimer (p = 0.037). Moreover, the combined diagnostic accuracy of elevated EXTEM MCF and CRP was improved compared with CRP alone (p = 0.019). CONCLUSIONS: Our results indicate that ROTEM analysis might be helpful for the detection of the hemostatic derangements that are associated with the development of PJI. However, because of the small size of this pilot study, further research is needed to investigate the value of incorporating viscoelastic studies in diagnostic scores for PJI. LEVEL OF EVIDENCE: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Monitoring the Coagulation Profile of COVID-19 Patients Using Standard and ClotPro® Hemostasis Tests.

Background and Objectives: Coagulation disorders during COVID-19 infection are associated with a poorer prognosis and higher disease severity because thrombosis and inflammation are two processes that interfere with each other. A very important issue for clinicians is timely and adequate hemostasis and inflammation monitoring to prevent and treat potentially lethal consequences. The aim of this study was to identify specific hemostatic parameters that are associated with a higher risk of intrahospital mortality. Materials and Methods: This study was approved by the Ethics Committee of the Clinical Center Nis in Serbia. One hundred and forty-two patients presented with COVID-19 ARDS and were admitted to the ICU in the Clinic for Anesthesiology at the Clinical Center Nis from 14 April 2020 to 25 May 2020. Upon admission, blood was collected for biochemical and coagulation testing. The data obtained were analyzed using the Statistical Package for Social Sciences (SPSS v. 25, Chicago, IL, USA). Results: Among all the parameters assessed, older age; increased levels of fibrinogen, INR, D-dimer, and presepsin; and higher results in the platelet aggregation tests (aggregation induced by adenosine diphosphate based on the ADP test (AU/min), aggregation induced by arachidonic acid based on the ASPI test (AU/min), and aggregation induced by thrombin based on the TRAP test (AU/min)) and some assays of the viscoelastic test (clot amplitude after 5 min in the extrinsic coagulation pathway based on the A5 EX-test (mm), clot amplitude after 10 min in the extrinsic coagulation pathway based on the A10 EX-test (mm), clot amplitude after 5 min regarding functional fibrinogen based on the A5 FIB-test (mm), clot amplitude after 10 min regarding functional fibrinogen based on the A10 FIB-test (mm), and maximum clot firmness based on the MCF FIB-test (mm)); and lower values of viscoelastic clotting time in the extrinsic coagulation pathway based on the CT EX-test (s) were significantly correlated with mortality. In the multivariate analysis, D-dimer levels above 860 ng/mL, higher TRAP test value bins, and values above the normal reference range of the A10 FIB test were found to be independent predictors of mortality. Conclusions: Sophisticated hemostasis parameters can contribute to early risk assessment, which has initially been performed only on the basis of patients' clinical status. Hypercoagulability is the main coagulation disorder in COVID-19 infection.

Acute pancreatitis induces a transient hypercoagulable state in murine models.

BACKGROUND/OBJECTIVES: Although understudied, risk of venous thromboembolism (VTE) appears to be increased during acute pancreatitis (AP). We aimed to further characterize a hypercoagulable state associated with AP utilizing thromboelastography (TEG), a readily available, point of care test. METHODS: AP was induced in C57/Bl6 mice using l-arginine and caerulein. TEG was performed with citrated native samples. The maximum amplitude (MA) and coagulation index (CI), a composite marker of coagulability, were evaluated. Platelet aggregation was assessed using whole blood collagen-activated platelet impedance aggregometry. Circulating tissue factor (TF), the initiator of extrinsic coagulation, was measured with ELISA. A VTE model using IVC ligation followed by measurement of clot size and weight was evaluated. After IRB approval and consent, blood samples from patients hospitalized with a diagnosis of AP were evaluated by TEG. RESULTS: Mice with AP displayed a significant increase in MA and CI, consistent with hypercoagulability. Hypercoagulability peaked at 24 h after induction of pancreatitis, then returned to baseline by 72 h. AP resulted in significantly increased platelet aggregation and elevated circulating TF. Increased clot formation with AP was observed in an in vivo model of deep vein thrombosis. In a proof of concept, correlative study, over two thirds of patients with AP demonstrated an elevated MA and CI compared to the normal range, consistent with hypercoagulability. CONCLUSIONS: Murine acute pancreatitis results in a transient hypercoagulable state that can be assessed by TEG. Correlative evidence for hypercoagulability was also demonstrated in human pancreatitis. Further study to correlate coagulation measures to incidence of VTE in AP is warranted.

Alternative blood products in trauma.

PURPOSE OF REVIEW: Hemorrhage and trauma-induced coagulopathy cause significant morbidity and mortality in trauma patients. Although blood products are the cornerstone of resuscitation, these resources are scarce, necessitating alternatives. This review examines the use of alternative blood products in trauma as well as the literature supporting their use. RECENT FINDINGS: There is no single true blood product alternative. In recent years, there has been great progress in understanding trauma-induced pathophysiology and blood component alternatives. Products such as tranexamic acid and prothrombin complex concentrate have become well established and are frequently utilized in trauma centers, and many more alternatives are still undergoing further research and development. SUMMARY: Stabilization of hemorrhage and resuscitation is priority in trauma-induced coagulopathy treatment. Alternative products such as tranexamic acid, recombinant factors, prothrombic complex concentrate, fibrinogen concentrates, and desmopressin may also be considered based on the clinical context. Viscoelastic hemostatic assays such as rotational thromboelastometry and thromboelastography can help guide these efforts. Following initial stabilization, additional interventions such as iron supplementation, erythropoietin stimulating agents, and vitamin D may help with chronic sequela.

Persistent fibrinolysis shutdown is associated with increased mortality in traumatic pancreatic injury.

PURPOSE: The features of fibrinolytic system modifications and their relationship with prognosis are still unknown in traumatic pancreatic injury. The object of this prospective cohort research was to identify fibrinolytic characteristics in patients with pancreatic trauma and to identify the correlation to mortality. METHOD: A prospective screening of traumatic pancreatic injury patients was done for five years. The fibrinolytic status of patients was determined by thromboelastography (TEG). The percentage reduction in clot strength 30 min (LY30) after the time of maximal clot strength was utilized to distinguish the fibrinolytic phenotype of individuals, including fibrinolytic shutdown (SD), physiologic fibrinolysis (PHYS) and hyperfibrinolysis (HF). Two cohorts, transient fibrinolytic shutdown (TSD) and persistent fibrinolytic shutdown (PSD), were divided according to whether fibrinolytic shutdown persisted within one week. Demographics, injury severity, characteristics of pancreatic injury, treatment, and outcomes were compared. RESULT: A total of 180 cases enrolled, aged 42(interquartile range 32-51) years, 88% males, 97% were blunt trauma. The median ISS was 19(IQR 10-25), and 76% were AAST grade III to V (high-grade). At admission, there were 159 cases of SD (88%), 15 cases of PHYS (8%) while 6 cases of HF (3%). Of these, the TSD cohort included 54 patients (34%), while the PSD cohort included 105 patients (66%). Compared with the TSD cohort, the PSD cohort had more severe injury (ISS 21[IQR 12-27] vs 16[IQR 9-22], p = 0.006) and a higher proportion of AAST high-grade (83% vs 67%, p = 0.035). Persistent fibrinolytic shutdown was associated with operative treatment (odds ratio [OR] 3.111; 95%CI 1.146-8.447; p = 0.026), associated intra-abdominal injury (OR 8.331; 95% CI 1.301-53.336; p = 0.025) and admission LY30 (OR 0.016; 95% CI 0.002 - 0.120; p < 0.001). It was an independent predictor of mortality (adjusted odds ratio [AOR] 4.674; 95% CI 1.03 to 21.14; p = 0.045). CONCLUSION: Fibrinolytic shutdown especially persistence of this phenotype is more common in traumatic pancreatic injury than PHYS and HF, which related with mortality. Risk factors including LY30 at admission, intra-abdominal injury and operative treatment were associated with the persistent fibrinolytic shutdown. Sheltered the patients from these risk factors seems to be beneficial, which need to be confirmed by further large-scale studies.

Thromboelastometry-guided surgery in neuroblastoma complicated with disseminated intravascular coagulation. / Cirugía guiada por tromboelastometría en neuroblastoma complicado con coagulación intravascular diseminada.

BACKGROUND: Disseminated intravascular coagulation (DIC) is a rare oncological emergency. We report a pediatric neuroblastoma complicated with DIC which required thromboelastometry-guided surgery. OBSERVATION: A 6-year-old female diagnosed with intermediate risk adrenal neuroblastoma developed tumor-related DIC after chemotherapy first cycle. She remained stable without clinical bleeding and emergent tumor resection guided by intraoperative-thromboelastometry was decided. DIC resolved early after surgery and complete remission was achieved. CONCLUSION: Treatment of the underlying condition is critical to manage DIC. Thromboelastometry can guide goal-directed therapy, including surgery in pediatric patients. However, larger studies are needed to examine its applicability in different clinical settings, such as cancer related DIC.

INTRODUCCION: La coagulación intravascular diseminada (CID) es una urgencia oncológica poco común. Describimos el caso de un neuroblastoma pediátrico complicado con CID que precisó de cirugía guiada por tromboelastometría. CASO CLINICO: Paciente de seis años diagnosticada de neuroblastoma suprarrenal de riesgo intermedio que desarrolló CID asociada al tumor tras el primer ciclo de quimioterapia. Permaneció estable sin hemorragia clínica, decidiéndose una resección tumoral de urgencia guiada por tromboelastometría intraoperatoria. La CID se resolvió poco después de la cirugía, consiguiéndose una remisión total. CONCLUSION: El tratamiento de la patología subyacente es clave a la hora de manejar la CID. La tromboelastometría puede guiar la terapia orientada a objetivos, también en cirugías realizadas en pacientes pediátricos. No obstante, hacen falta mayores estudios que analicen su aplicabilidad en distintos contextos clínicos, como la CID relacionada con cáncer.

Mitochondrial Dysfunction in Trauma-Related Coagulopathy: Is There Causality? Study Protocol for a Prospective Observational Study.

Hemorrhage control often poses a great challenge for clinicians due to trauma-induced coagulopathy (TIC). The pathogenesis of TIC is not completely revealed; however, growing evidence attributes a central role to altered platelet biology. The activation of thrombocytes and subsequent clot formation are highly energetic processes being tied to mitochondrial activity, and the inhibition of the electron transport chain (ETC) impedes on thrombogenesis, suggesting the potential role of mitochondria in TIC. Our present study protocol provides a guide to quantitatively characterize the derangements of mitochondrial functions in TIC. One hundred eleven severely injured (injury severity score ≥16), bleeding trauma patients with an age of 18 or greater will be included in this prospective observational study. Patients receiving oral antiplatelet agents including cyclooxygenase-1 or adenosine diphosphate receptor inhibitors (aspirin, clopidogrel, prasugrel, and ticagrelor) will be excluded from the final analysis. Hemorrhage will be confirmed and assessed with computer tomography. Conventional laboratory markers of hemostasis such as prothrombin time and international normalized ratio will be measured and rotational thromboelastometry (ROTEM) will be performed directly upon patient arrival. Platelets will be isolated from venous blood samples and subjected to high-resolution fluororespirometry (Oxygraph-2k, Oroboros Instruments, Innsbruck, Austria) to evaluate the efficacy of mitochondrial respiration. Oxidative phosphorylation (OxPhos), coupling of the ETC, mitochondrial superoxide formation, mitochondrial membrane potential changes, and extramitochondrial Ca2+-movement will be recorded. The association between OxPhos capacity of platelet mitochondria and numerical parameters of ROTEM aggregometry will constitute our primary outcome. The relation between OxPhos capacity and results of viscoelastic assays and conventional markers of hemostasis will serve as secondary outcomes. The association of the OxPhos capacity of platelet mitochondria upon patient arrival to the need for massive blood transfusion and 24-h mortality will constitute our tertiary outcomes. Mitochondrial dysfunction and its importance in TIC are yet to be assessed for the deeper understanding of this common, life-threatening condition. Disclosure of mitochondria-mediated processes in thrombocytes may reveal new therapeutic targets in the management of hemorrhaging trauma patients, thereby leading to a reduction of potentially preventable mortality. The present protocol was registered to ClinicalTrials.gov on 12 August 2021, under the reference number NCT05004844.

Association of Thromboelastography with Progression of Hemorrhagic Injury in Children with Traumatic Brain Injury.

INTRODUCTION: Progression of hemorrhagic injury (PHI) in children with traumatic brain injury portends poor outcomes. The association between thromboelastography (TEG), functional coagulation assays, and PHI is not well characterized in children. METHODS: This was a retrospective cohort study of children presenting with PHI at a pediatric level I academic trauma center from 2015 to 2020. Inclusion criteria were as follows: age less than 18 years, intracranial hemorrhage on admission head computed tomography scan, and admission rapid TEG assay and conventional coagulation tests. PHI was defined by the following radiographic criteria: any expansion of or new intracranial hemorrhage on subsequent head computed tomography scan. Rapid TEG values included Activated Clotting Time (ACT), alpha angle, maximum amplitude, and lysis at 30 min. Wilcoxon rank-sum test was used to assess baseline differences between groups with PHI and without PHI, including laboratory assays. Univariate analysis was performed to examine the association between variables of interest and PHI. Patients were dichotomized on the basis of this cut point to generate a "low ACT" group and a "high ACT" group. These variables were included in a multivariable logistic regression model to determine independent association with traumatic brain injury progression. RESULTS: In total, 219 patients met criteria for analysis. In this cohort, the median (interquartile range [IQR]) age = 6 (2-12) years, median (IQR) Injury Severity Score = 21 (11-27), 68% were boys, and 69% sustained blunt injury. The rate of PHI was 25% (54). Median (IQR) time to PHI was 1 (0-4) days. Children with PHI had a higher Injury Severity Score (p < 0.001), lower Glasgow Coma Scale (p < 0.001), greater incidence of shock (p = 0.04), and lower admission hemoglobin (p = 0.02) compared with those without PHI. Children with PHI had a higher International Normalized Ratio (INR) and longer TEG-ACT; other TEG values (alpha angle, maximum amplitude, and lysis at 30 min) were not associated with PHI. In the logistic regression model accounting for other covariates associated with PHI, elevated ACT remained an independent predictor of progression (odds ratio = 2.25, 95% confidence interval 1.09-4.66; p = 0.03; area under the receiver operating characteristic curve = 0.76). After adjusting for confounders, INR fell out of the model and was not an independent predictor of progression (odds ratio = 1.32, 95% confidence interval 0.60-2.93; p = 0.49). CONCLUSIONS: Although INR was elevated in children with PHI and has been associated with poor clinical outcomes, only admission TEG-ACT was independently associated with PHI. Further study is warranted to determine whether TEG-ACT reflects an actionable therapeutic target.

Hemorrhagic shock and tissue injury provoke distinct components of trauma-induced coagulopathy in a swine model.

INTRODUCTION: Tissue injury (TI) and hemorrhagic shock (HS) are the major contributors to trauma-induced coagulopathy (TIC). However, the individual contributions of these insults are difficult to discern clinically because they typically coexist. TI has been reported to release procoagulants, while HS has been associated with bleeding. We developed a large animal model to isolate TI and HS and characterize their individual mechanistic pathways. We hypothesized that while TI and HS are both drivers of TIC, they provoke different pathways; specifically, TI reduces time to clotting, whereas, HS decreases clot strength stimulates hyperfibrinolysis. METHODS: After induction of general anesthesia, 50 kg male, Yorkshire swine underwent isolated TI (bilateral muscle cutdown of quadriceps, bilateral femur fractures) or isolated HS (controlled bleeding to a base excess target of - 5 mmol/l) and observed for 240 min. Thrombelastography (TEG), calcium levels, thrombin activatable fibrinolysis inhibitor (TAFI), protein C, plasminogen activator inhibitor 1 (PAI-1), and plasminogen activator inhibitor 1/tissue-type plasminogen activator complex (PAI-1-tPA) were analyzed at pre-selected timepoints. Linear mixed models for repeated measures were used to compare results throughout the model. RESULTS: TI resulted in elevated histone release which peaked at 120 min (p = 0.02), and this was associated with reduced time to clot formation (R time) by 240 min (p = 0.006). HS decreased clot strength at time 30 min (p = 0.003), with a significant decline in calcium (p = 0.001). At study completion, HS animals had elevated PAI-1 (p = 0.01) and PAI-1-tPA (p = 0.04), showing a trend toward hyperfibrinolysis, while TI animals had suppressed fibrinolysis. Protein C, TAFI and skeletal myosin were not different among the groups. CONCLUSION: Isolated injury in animal models can help elucidate the mechanistic pathways leading to TIC. Our results suggest that isolated TI leads to early histone release and a hypercoagulable state, with suppressed fibrinolysis. In contrast, HS promotes poor clot strength and hyperfibrinolysis resulting in hypocoagulability.

Evaluation of Blood Coagulation by Optical Vortex Tracking.

Blood coagulation is a complicated dynamic process that maintains the blood's fluid state and prevents uncontrollable bleeding. The real-time monitoring of coagulation dynamics is critical for blood transfusion guidance, emergency management of trauma-induced coagulopathy, perioperative bleeding, and targeted hemostatic therapy. Here, we utilize optical vortex dynamics to detect the blood coagulation dynamic process in a rapid and non-contact manner. To characterize the temporal changes in viscoelastic properties of blood during coagulation, we track the stochastic motion of optical vortices in the time-varying speckles reflected from 100 blood samples with varied coagulation profiles. The mean square displacement (MSD) of the vortices increases nonlinearly with time lag during blood coagulation reminiscent of the particles in viscoelastic fluids. The MSD curves with coagulation time are similar to the tracings of thromboelastography (TEG) during the blood coagulation. The retrieved coagulation parameters, such as reaction time and activated clotting time measured using the optical vortex method, exhibit a close correlation to those parameters acquired from TEG. These results demonstrate the feasibility of the optical vortex method for monitoring blood coagulation at the point of care. Our method is also applicable to measuring the viscoelasticity of complex fluids and turbid soft matters.

Review article: thromboelastography in liver diseases.

BACKGROUND: Patients with liver diseases have complicated haemostatic alternations, resulting in both bleeding and thromboembolic complications, which cannot be sufficiently evaluated by conventional coagulation tests (CCTs), such as platelet count or prothrombin time. Thromboelastography (TEG) is a whole blood viscoelastic test which globally reflects changes in the haemostatic system, and its utility in evaluating patients with liver disease is increasingly recognised. AIMS: To review the current evidence and clinical significance of TEG in liver diseases. METHODS: Literature regarding TEG and liver diseases was comprehensively searched. RESULTS: TEG is associated closely with the severity and aetiology of liver disease, the course of infection and the risk of bleeding and death, but not the risk of portal venous system thrombosis. Additionally, TEG-guided transfusion protocols can significantly decrease the requirement for blood products compared to those guided by CCTs. CONCLUSION: TEG can reflect the haemostatic status of liver diseases more comprehensively than CCTs. It has the potential to assess the severity of liver diseases, predict the risk of bleeding and death in patients with liver disease and guide blood product transfusion. Future studies should standardise the use of TEG for assessing disease severity and development of clinical events and guiding blood product transfusion in patients with liver diseases.

Persistence of procoagulable thromboelastography results in hospitalized COVID-19 patients despite clinical improvement.

OBJECTIVE: COVID-19 patients have been shown to be hypercoagulable, increasing the risk for thromboembolic events. The kinetics of the blood coagulation process were monitored daily throughout hospitalization in COVID-19 positive patients. PATIENTS AND METHODS: Thromboelastography (TEG) was used to assess blood coagulation in 48 adult patients hospitalized for COVID-19 in this prospective cohort study. Clinical risk was assessed via National Early Warning Scores (NEWS) for each day of hospitalization. RESULTS: During hospitalization, 98% of patients had one or more procoagulable TEG result. Thromboelastography results remained prothrombotic upon discharge in 80% of patients. NEWS significantly decreased by discharge compared to the peak scores. CONCLUSIONS: Overall, patients were discharged from the hospital with significant clinical improvement, but without abnormal TEG results returning to a normal range. All patients in our study survived and few had thromboembolic events, so if and for how long these patients remain at risk for future complications warrants further investigation.

The vexing triad of obesity, alcohol, and coagulopathy predicts the need for multiple operations in liver transplantation.

INTRODUCTION: One in four liver transplants (LT) require return to the operating room(R-OR) within 48 h of surgery. We hypothesize that donor, recipient, and intraoperative factors will predict R-OR. METHODS: LT recipients were enrolled in an observational study to measure coagulation with thrombelastography (TEG) were assessed with transplant recipient and donor variables for risk of R-OR. RESULTS: 160 recipients with a median age of 55 years and a MELD-Na of 22 were analyzed. R-OR occurred in 22%. Recipient BMI (p = 0.006), donor heavy alcohol use (p = 0.017), TEG MA (p = 0.013) during the anhepatic phase of surgery, TEG MA at anhepatic and 30-min after reperfusion (p < 0.05), and red blood cell transfusions (p < 0.001) were associated with R-OR. CONCLUSION: The vexing triad of recipient obesity, heavy donor alcohol use, and low TEG MA were associated with a high rate of R-OR. Strategies to reduce this sub-optimal combination of risk factors could reduce the frequency of unplanned re-operations.

Viscoelastic Testing Prior to Non-surgical Procedures Reduces Blood Product Use Without Increasing Bleeding Risk in Cirrhosis.

BACKGROUND/AIMS: Thromboelastography (TEG) and Rotational Thromboelastometry (ROTEM) analyze hemostatic function in patients with coagulopathy. We sought to quantify the impact of TEG and ROTEM-guided transfusion algorithms on blood product utilization in patients with cirrhosis undergoing non-surgical procedures. METHODS: We performed a systematic review and meta-analysis on the utility of viscoelastic testing prior to non-surgical procedures to determine their impact on pre-procedural blood product use and post-procedural bleeding events. Studies comparing TEG or ROTEM-guided transfusions with standard-of-care (SOC) prior to non-surgical procedures in adult patients with cirrhosis were included. Primary outcomes were fresh frozen plasma (FFP) and platelet transfusion and secondary outcomes of post-procedure bleeding, transfusion-related complications, and mortality; and were reported as standardized mean differences (SMD) and risk ratios (RR). RESULTS: Six studies (five randomized controlled trials and one cohort study) involving 367 patients met inclusion criteria. Compared with SOC, TEG/ROTEM-guided transfusions led to an overall decreased number of patients who received FFP transfusions (SMD = -0.93, 95% CI [-1.54, -0.33], p < 0.001) and platelets transfusions (SMD = -1.50, CI [-1.85, -1.15], p < 0.001). Total amount of FFP (SMD-0.86, p < 0.001) and platelet (SMD = -0.99, p < 0.001) transfused in the TEG/ROTEM group were also lower. Decreased pre-procedure transfusion in the TEG/ROTEM group did not result in increased post-procedure bleeding (RR = 0.61, p = 0.09) or in mortality (RR = 0.91, p = 0.93). CONCLUSION: In patients with cirrhosis, TEG or ROTEM significantly reduces blood product utilization prior to non-surgical procedures, with no increase in post-procedure bleeding or mortality. TEG and ROTEM utilization can promote high-value care and improve transfusion stewardship in this population.

Questions about COVID-19 associated coagulopathy: possible answers from the viscoelastic tests.

Abnormal coagulation parameters are often observed in patients with coronavirus disease 2019 (COVID-19) and the severity of derangement has been associated with a poor prognosis. The COVID-19 associated coagulopathy (CAC) displays unique features that include a high risk of developing thromboembolic complications. Viscoelastic tests (VETs), such as thromboelastometry (ROTEM), thromboelastography (TEG) and Quantra Hemostasis Analyzer (Quantra), provide "dynamic" data on clot formation and dissolution; they are used in different critical care settings, both in hemorrhagic and in thrombotic conditions. In patients with severe COVID-19 infection VETs can supply to clinicians more information about the CAC, identifying the presence of hypercoagulable and hypofibrinolysis states. In the last year, many studies have proposed to explain the underlying characteristics of CAC; however, there remain many unanswered questions. We tried to address some of the important queries about CAC through VETs analysis.

Potential Applicability of Perioperative Thromboelastography to Access the Coagulopathies in Live-Related Renal Transplantation - A Prospective Observational Pilot Study.

Ischemic and reperfusion injury (IRI) occurs during organ transplantation. IRI during liver transplantation is well studied and established; results in coagulopathy due to release of heparin-like substances and platelet trapping. During renal transplantation, similar IRI phenomenon occurs, and thromboelastography (TEG) can be used to detect and manage coagulopathy. The preoperative, immediate postreperfusion, and postoperative day 1 TEG was done on 25 cases of live-related renal transplantation. Coagulopathy was defined by deranged and abnormal TEG variables values from baseline and supported by the clinical presence of nonsurgical oozing and bleeding in the surgical field. The postreperfusion TEG values showed coagulopathic changes. About 64% of patients had R-time (RT) more than 12 min, 64% of patients showed maximum amplitude (MA) <55 mm, and 76% of patients had alpha angle <55°. The presurgical TEG clotting index (CI) was +2.45 ± 1.25, postreperfusion CI was -1.96 ± 4.54, and postoperative CI was +4.02 ± 1.35. Univariate analysis revealed that antithymocyte globulin was a significant, but etiology was closure to a significant level as protecting factor, but in multivariate analysis, both variables showed protecting factor with insignificant results. There was a weak correlation between CI with serum creatinine at all time points suggested no linear relationship between serum creatinine and corresponding CI. Hence, the results of study proves that IRI during renal transplant is associated with transient self-limiting coagulopathy, that may be early detected by TEG. CI values in postoperative 24 h apart indicating a hyper-coagulable or prothrombotic state and post-reperfusion CI values show a trend toward hypocoagulable status. No significant effect of different immunosuppression on coagulation and week correlation was found of serum creatinine level (graft function) with CI, which conclude that changes in coagulation have not affected graft function.