Assessment of Haemostasis in Disseminated Intravascular Coagulation by Use of Point-of-Care Assays and Routine Coagulation Tests, in Critically Ill Patients; A Prospective Observational Study

Platelet Function in Patients with Disseminated Intravascular Coagulation: Potential Markers for Improving DIC Diagnosis?

Disseminated intravascular coagulation (DIC) is a severe complication often associated with critical illness. DIC is characterized by an uncontrolled systemic activation of the hemostatic system, leading to substantial consumption of platelets and coagulation factors. The diagnosis of DIC relies on a combination of clinical findings and laboratory results, yet DIC remains challenging to confirm, especially in early stages. This systematic review investigates the reported associations between platelet function and DIC and evaluates the potential of using platelet function markers as a supplement for DIC diagnosis. PubMed and Embase were searched for relevant literature. Human studies, which included patients with DIC and assessed platelet function using dynamic platelet function assays or soluble markers, were included. In total, 24 studies met the inclusion criteria. We found that DIC patients generally exhibit increased platelet activation in vivo, indicated by elevated plasma levels of soluble markers, while ex vivo platelet aggregation was consistently reduced compared to non-DIC patients and healthy controls; however, not all studies adjusted their results for platelet count. Soluble P-selectin was the most frequently studied plasma marker and was consistently increased in DIC patients; this was most pronounced when adjusted for platelet count. However, there was considerable heterogeneity between studies regarding both study design, patient populations, platelet function assessment, and DIC diagnosis, which complicates the comparison of findings across studies. Future studies accounting for low platelet counts in dynamic function tests are necessary to assess the role of platelet aggregation in relation to DIC.

Inflammation, immunity and biomarkers in procoagulant responses of critically ill patients

Understanding the pathobiology of critical illness is essential for patients' prognosis. Sepsis is a life-threatening organ dysfunction caused by a dysregulated host response to infection. As part of the host response, procoagulant responses, one of the most primitive reactions in biology, start at the very beginning of diseases and can be monitored throughout the process. Currently, we can achieve near-complete monitoring of the coagulation process, and procoagulant responses serve as indicators of the severity of host response in critically ill patients. However, the rapid interpretation of the complex results of various biomarkers remains a challenge for many clinicians. The indicators commonly used for coagulation assessment are complex, typically divided into three categories for clarity: process index, functional index, and outcome index. Monitoring and understanding these indicators can help manage procoagulant responses. The intervention of procoagulant response should be part of the bundle therapy, alongside the treatment for primary disease, management for hemodynamics, and controlling for host response. Early intervention for procoagulant response mainly includes anti-inflammation, antiplatelet and anticoagulant therapy, as well as management of primary disease. In this review, we systemically introduce the onset, assessment and intervention of procoagulant response.

Practical approach to thrombocytopenia in patients with sepsis: a narrative review

Thrombocytopenia frequently occurs in patients with sepsis. Disseminated intravascular coagulation (DIC) may be a possible cause of thrombocytopenia owing to its high prevalence and association with poor outcomes; however, it is important to keep the presence of other diseases in mind in sepsis practice. Thrombotic microangiopathy (TMA), which is characterized by thrombotic thrombocytopenic purpura, Shiga toxin-producing Escherichia coli hemolytic uremic syndrome (HUS), and complement-mediated HUS, is characterized by thrombocytopenia, microangiopathic hemolytic anemia, and organ damage. TMA has become widely recognized in recent years because of the development of specific treatments. Previous studies have reported a remarkably lower prevalence of TMA than DIC; however, its epidemiology is not well defined, and there may be cases in which TMA is not correctly diagnosed, resulting in poor outcomes. Therefore, it is important to differentiate DIC from TMA. Nevertheless, differentiating between DIC and TMA remains a challenge as indicated by previous reports that most patients with TMA can be diagnosed as DIC using the universal coagulation scoring system. Several algorithms to differentiate sepsis-related DIC from TMA have been suggested, contributing to improving the care of septic patients with thrombocytopenia; however, it may be difficult to apply these algorithms to patients with coexisting DIC and TMA, which has recently been reported. This review describes the disease characteristics, including epidemiology, pathophysiology, and treatment, of DIC, TMA, and other diseases with thrombocytopenia and proposes a novel practical approach flow, which is characterized by the initiation of the diagnosis of TMA in parallel with the diagnosis of DIC. This practical flow also refers to the longitudinal diagnosis and treatment flow with TMA in mind and real clinical timeframes. In conclusion, we aim to widely disseminate the results of this review that emphasize the importance of incorporating consideration of TMA in the management of septic DIC. We anticipate that this practical new approach for the diagnostic and treatment flow will lead to the appropriate diagnosis and treatment of complex cases, improve patient outcomes, and generate new epidemiological evidence regarding TMA.

Hemorrhage in acute promyelocytic leukemia-fibrinolysis in focus

Coagulopathy continues to be a major challenge in the management of patients with acute promyelocytic leukemia (APL). Novel differentiating agents have led to improved survival in these patients, but perturbations in coagulation continue to have an impact on their prognosis. The most worrisome of coagulation disturbances is bleeding, which is not an uncommon cause of early death in APL. Despite this, there are no consistent predictors of this high risk of fatal hemorrhage in APL. In this context, the fibrinolytic system has been identified as a crucial role player in APL coagulopathy. However, the current guidelines for the management of APL give little regard to tests that measure the fibrinolytic system while giving more importance to close monitoring of conventional coagulation tests and platelet counts to identify the coagulopathy. More recently, viscoelastic tests have come to usefulness in determining global hemostasis and have been widely used for "diagnosing" hyperfibrinolysis in selected clinical settings. In this review, we attempt to describe risk assessment models for diagnosing APL coagulopathy, describe the possible application of viscoelastic tests in this setting, and persuade clinicians to reconsider the use of antifibrinolytics to improve survival of APL patients.

Cryopreserved Platelets in a Non-Toxic DMSO-Free Solution Maintain Hemostatic Function In Vitro

Dimethyl sulfoxide (DMSO) is regularly used as a cryoprotectant agent for the cryopreservation of platelets. However, DMSO is considered toxic. We therefore hypothesized that saline could be used as a non-toxic medium for the cryopreservation of platelets. Double-dose buffy coat platelets (n = 10) were divided and cryopreserved at -80 °C using 5-6% dimethyl sulfoxide (DMSO) or in NaCl (9 mg/mL). Paired testing was conducted pre-freeze, post-thaw (PT 1 h). Upon analysis, each bag was thawed and reconstituted in fresh plasma. Analyses included cell counts and the metabolic, phenotypic, and functional properties of the platelets together with thromboelastometry. The cryopreserved platelets showed several biochemical and ultrastructural changes compared to pre-freezing. Platelet recovery was approximately 17% higher in DMSO-free units (p < 0.001), but the platelet viability was reduced (p < 0.001). However, using controlled freezing (n = 6), the platelet viability was improved. The clot formation time (CFT) was comparable, but DMSO-free platelets showed slightly decreased maximum clot firmness (MCF) (p = 0.034). By reducing the reconstituted plasma volume, a reduced CFT and increased MCF were obtained (p < 0.001). This study demonstrates that platelets can be cryopreserved in saline without the addition of DMSO, with high recovery and maintained hemostatic function. However, controlled freezing is required to optimize platelet quality.

Geldanamycin ameliorates multiple organ dysfunction and microthrombosis in septic mice by inhibiting the formation of the neutrophil extracellular network by activating heat shock factor 1 HSF1

Sepsis and septic shock are common critical illnesses in the intensive care unit with a high mortality rate. Geldanamycin (GA) has a broad spectrum of antibacterial and antiviral activity and has inhibitory effects on various viruses. However, whether GA affects sepsis due to infections remains unknown. In this study, alanine aminotransferase, aspartate aminotransferase, blood urea nitrogen and creatinine in serum; neutrophil gelatinase-associated lipocalin and kidney injury molecule-1 in the urine, cytokines (tumour necrosis factor alpha, interleukin-1β and interleukin-6) in the bronchoalveolar lavage fluid and myeloperoxidase in the lung tissues were measured using enzyme-linked immunosorbent assay kits. Pathological injury was measured by hematoxylin and eosin staining and neutrophils were measured by flow cytometry analysis; related expressions were analysed by qPCR, western blot and immunofluorescence assay. The results showed that GA significantly ameliorated cecum ligation and puncture (CLP)-triggered liver, kidney and lung injury in septic mice. In addition, we found that GA dose-dependently inhibited microthrombosis and alleviated coagulopathy in septic mice. Further molecular mechanism analysis suggests that GA may act through upregulation of heat shock factor 1 and tissue-type plasminogen activator. In conclusion, our study elucidated the protective effects of GA in a mouse model established using CLP, and the results reveal that GA may be a promising agent for sepsis.

The Choice between Plasma-Based Common Coagulation Tests and Cell-Based Viscoelastic Tests in Monitoring Hemostatic Competence: Not an either-or Proposition

There has been a significant interest in the last decade in the use of viscoelastic tests (VETs) to determine the hemostatic competence of bleeding patients. Previously, common coagulation tests (CCTs) such as the prothrombin time (PT) and partial thromboplastin time (PTT) were used to assist in the guidance of blood component and hemostatic adjunctive therapy for these patients. However, the experience of decades of VET use in liver failure with transplantation, cardiac surgery, and trauma has now spread to obstetrical hemorrhage and congenital and acquired coagulopathies. Since CCTs measure only 5 to 10% of the lifespan of a clot, these assays have been found to be of limited use for acute surgical and medical conditions, whereby rapid results are required. However, there are medical indications for the PT/PTT that cannot be supplanted by VETs. Therefore, the choice of whether to use a CCT or a VET to guide blood component therapy or hemostatic adjunctive therapy may often require consideration of both methodologies. In this review, we provide examples of the relative indications for CCTs and VETs in monitoring hemostatic competence of bleeding patients.

Transfusion Strategies for Hemostatic Blood Products in Critically Ill Children: A Narrative Review and Update on Expert Consensus Guidelines

Critically ill children commonly receive coagulant products (plasma and/or platelet transfusions) to prevent or treat hemorrhage or correct coagulopathy. Unique aspects of pediatric developmental physiology, and the complex pathophysiology of critical illness must be considered and balanced against known transfusion risks. Transfusion practices vary greatly within and across institutions, and high-quality evidence is needed to support transfusion decision-making. We present recent recommendations and expert consensus statements to direct clinicians in the decision to transfuse or not to transfuse hemostatic blood products, including plasma, platelets, cryoprecipitate, and recombinant products to critically ill children.

Assay validity of point-of-care platelet function tests in thrombocytopenic blood samples

Introduction

Point-of-care (POC) platelet function tests are faster and easier to perform than in-depth assessment by flow cytometry. At low platelet counts, however, POC tests are prone to assess platelet function incorrectly. Lower limits of platelet count required to obtain valid test results were defined and a testing method to facilitate comparability between different tests was established.

Materials and methods

We assessed platelet function in whole blood samples of healthy volunteers at decreasing platelet counts (> 100, 80-100, 50-80, 30-50 and < 30 x109/L) using two POC tests: impedance aggregometry and in-vitro bleeding time. Flow cytometry served as the gold standard. The number of platelets needed to reach 50% of the maximum function (ED50) and the lower reference limit (EDref) were calculated to define limits of test validity.

Results

The minimal platelet count required for reliable test results was 100 x109/L for impedance aggregometry and in-vitro bleeding time but only 30 x109/L for flow cytometry. Comparison of ED50 and EDref showed significantly lower values for flow cytometry than either POC test (P value < 0.05) but no difference between POC tests nor between the used platelet agonists within a test method.

Conclusion

Calculating the ED50 and EDref provides an effective way to compare values from different platelet function assays. Flow cytometry enables correct platelet function testing as long as platelet count is > 30 x109/L whereas impedance aggregometry and in-vitro bleeding time are inconsistent unless platelet count is > 100 x109/L.

Disseminated intravascular coagulation and its immune mechanisms

Disseminated intravascular coagulation (DIC) is a syndrome triggered by infectious and noninfectious pathologies characterized by excessive generation of thrombin within the vasculature and widespread proteolytic conversion of fibrinogen. Despite diverse clinical manifestations ranging from thrombo-occlusive damage to bleeding diathesis, DIC etiology commonly involves excessive activation of blood coagulation and overlapping dysregulation of anticoagulants and fibrinolysis. Initiation of blood coagulation follows intravascular expression of tissue factor or activation of the contact pathway in response to pathogen-associated or host-derived, damage-associated molecular patterns. The process is further amplified through inflammatory and immunothrombotic mechanisms. Consumption of anticoagulants and disruption of endothelial homeostasis lower the regulatory control and disseminate microvascular thrombosis. Clinical DIC development in patients is associated with worsening morbidities and increased mortality, regardless of the underlying pathology; therefore, timely recognition of DIC is critical for reducing the pathologic burden. Due to the diversity of triggers and pathogenic mechanisms leading to DIC, diagnosis is based on algorithms that quantify hemostatic imbalance, thrombocytopenia, and fibrinogen conversion. Because current diagnosis primarily assesses overt consumptive coagulopathies, there is a critical need for better recognition of nonovert DIC and/or pre-DIC states. Therapeutic strategies for patients with DIC involve resolution of the eliciting triggers and supportive care for the hemostatic imbalance. Despite medical care, mortality in patients with DIC remains high, and new strategies, tailored to the underlying pathologic mechanisms, are needed.

Viscoelastic Hemostatic Assays: A Primer on Legacy and New Generation Devices

Viscoelastic hemostatic assay (VHAs) are whole blood point-of-care tests that have become an essential method for assaying hemostatic competence in liver transplantation, cardiac surgery, and most recently, trauma surgery involving hemorrhagic shock. It has taken more than three-quarters of a century of research and clinical application for this technology to become mainstream in these three clinical areas. Within the last decade, the cup and pin legacy devices, such as thromboelastography (TEG^® 5000) and rotational thromboelastometry (ROTEM^® delta), have been supplanted not only by cartridge systems (TEG^® 6S and ROTEM^® sigma), but also by more portable point-of-care bedside testing iterations of these legacy devices (e.g., Sonoclot^®, Quantra^®, and ClotPro^®). Here, the legacy and new generation VHAs are compared on the basis of their unique hemostatic parameters that define contributions of coagulation factors, fibrinogen/fibrin, platelets, and clot lysis as related to the lifespan of a clot. In conclusion, we offer a brief discussion on the meteoric adoption of VHAs across the medical and surgical specialties to address COVID-19-associated coagulopathy.

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.

Viscoelastic testing in oncology patients (including for the diagnosis of fibrinolysis): Review of existing evidence, technology comparison, and clinical utility

The quantification of the coagulopathic state associated with oncologic and hematologic diseases is imperfectly assessed by common coagulation tests such as prothrombin time, activated partial thromboplastin time, fibrinogen levels, and platelet count. These tests provide a static representation of a component of hemostatic integrity, presenting an incomplete picture of coagulation in these patients. Viscoelastic tests (VETs), such as rotational thromboelastometry (ROTEM) and thromboelastography (TEG), as whole blood analyses, provide data related to the cumulative effects of blood components and all stages of the coagulation and fibrinolytic processes. The utility of VETs has been demonstrated since the late 1960s in guiding blood component therapy for patients undergoing liver transplantation. Since then, the scope of viscoelastic testing has expanded to become routinely used for cardiac surgery, obstetrics, and trauma. In the past decade, VETs' expanded usage has been most significant in trauma resuscitation. However, use of VETs for patients with malignancy-associated coagulopathy (MAC) and hematologic malignancies is increasing. For the purposes of this narrative review, we discuss the similarities between trauma-induced coagulopathy (TIC) and MAC. These similarities center on the thrombomodulin-thrombin complex as it switches between the thrombin-activatable fibrinolysis inhibitor coagulation pathway and activating the protein C anticoagulation pathway. This produces a spectrum of coagulopathy and fibrinolytic alterations ranging from shutdown to hyperfibrinolysis that are common to TIC, MAC, and hematologic malignancies. There is expanding literature regarding the utility of TEG and ROTEM to describe the hemostatic integrity of patients with oncologic and hematologic conditions, which we review here.

Coagulopathy After Viper Snakebite in Vietnam and Relationship with Time of Admission

Background

Snakebite envenoming is a potentially life-threatening condition and causes many serious consequences.

Subjects and Methods

Therefore, this study aimed to throw some light on coagulopathy after Viperidae envenomations at Vietnam Poison Control Center and the relationship between coagulopathy and time of admission. A prospective, descriptive study was conducted from October 2016 to April 2018. The survey questionnaire included socio-economic characteristics, characteristics of snakebite, signs and clinical symptoms and blood test. Disseminated intravascular coagulation (DIC) condition was diagnosed using the International Society on Thrombosis and Haemostasis (ISTH) criteria. Rotational thromboelastometry was evaluated using ROTEM^® delta system.

Results

A total of 41 cases of viper snakebite with the mean age of snakebite victims were 41.27 ± 14.72 years old. Mean hospital stay of the patients was 5.63± 3.29 days. The association between coagulation disorder and clotting time (CT) EXTEM prolonged, CT INTEM prolonged, CT FIBTEM prolonged remained significant (multivariable odds ratio MOR=5.81, 95% CI: 1.20–28.06; MOR= 9.32, 95% CI: 1.001–84.48; MOR=5.55, 95% CI: 1.12–27.50, respectively).

Conclusion

This study indicates a hypocoagulation status in ROTEM, elevated international normalised ratio (INR), activated partial thromboplastin time (APTT) and D-dimer, decreased fibrinogen concentration and platelet count following envenoming by Viperidae.

Disseminated Intravascular Coagulopathy in Critically Ill Patients in Amman, Jordan

BACKGROUND

The disseminated intravascular coagulation (DIC) is under-recognized in critically ill patients. The International Society of Thrombosis and Haemostasis (ISTH; DIC) provides a useful scoring system for accurate DIC identification. The study investigated the period prevalence of ISTH DIC from 2015 to 2017 in critically ill patients.

METHODS

In this multi-center, retrospective observational study, we included all patients identified with a DIC code or medically diagnosed with DIC during all admissions. Based on ISTH DIC scores ≥ 5, patients were classified with overt DIC.

RESULTS

A total of 220 patients were included in this study. The period prevalence of DIC was 4.45%. The point prevalence of DIC has increased from 3.49% to 5.58% from 2015 to 2017 (27.7% female; median age 61.6 years). Based on the ISTH-Overt DIC criteria, 45.2% of the sample had sepsis. Overt DIC patients had significantly lower baseline hemoglobin (HB; t = 2.137, df = 193, p = 0.034), platelet count (t = 3.591, df = 193, p < 0.001) and elevated serum creatinine level (M = 2.1, SD = 1.5, t = 2.203, df = 193, p = 0.029) compared to non-Overt DIC. There was a statistically significant elevation in FDPs among Overt DIC compared to non-Overt DIC (χ² = 30.381, df = 1, p < 0.001). Overt DIC patients had significantly prolonged PT (U = 2,298, z = 5.7, p < 0.001), PTT (U = 2,334, z = 2.0, p = 0.045) and INR (U = 2,541, z = 5.1, p < 0.001) compared to those with non-Overt DIC.

CONCLUSION

The ISTH overt-DIC score can be used in critically ill patients regardless of the underlying disease. Efforts are required to predict and identify overt DIC using a valid scoring system on admission and follow-up of adult patients admitted to ICU.

Standard and derived rotational thromboelastometry parameters for prediction of disseminated intravascular coagulation in septic patients

: Waiting for lab tests results for the calculation of disseminated intravascular coagulation (DIC) scores leads to unwanted delays in diagnosis. The use of rotational thromboelastometry (ROTEM) for this purpose would allow for a more rapid DIC diagnosis at the bedside. The aim of this study was to assess the ability of standard ROTEM parameters and calculated parameters from the ROTEM velocity curve to predict DIC. The retrospective observational study included 97 septic patients. Japanese Association for Acute Medicine score was used for DIC diagnosis and whole-blood ROTEM was performed at study inclusion. Univariate analysis revealed delayed coagulation initiation and propagation and reduced clot firmness and maximum elasticity in DIC patients compared with patients without DIC. To adjust for confounders, multivariable logistic regression models were created and fibrinogen levels, prothrombin time and ROTEM parameters such as maximum clot firmness, maximum clot elasticity (MCE) and total thrombus formation [area under the curve (AUC)] were identified as significant predictors of DIC. According to receiver operating characteristics analysis, MCE and total thrombus formation (AUC) were the most useful ROTEM parameters for DIC prediction. MCE less than 158 (73% sensitive, 80% specific) and AUC less than 6175 mm × 100 (73% sensitive, 76% specific) predicted DIC in septic patients. Both standard and derived ROTEM parameters are useful for rapid DIC prediction in septic patients, allowing the timely identification of patients with higher mortality risk which might benefit from additional therapies. Further studies are needed to assess the clinical relevance of these findings.

An unexpected death after low anterior resection due to disseminated intravascular coagulation: A case report

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Disseminated intravascular coagulation can develop due to unrecognized sepsis.

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It can have a life-threatening course even in young, previously healthy patients.

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Rotational thromboelastometry may aid in guiding the treatment.

Introduction

Disseminated intravascular coagulation (DIC) is a blood clotting disorder that is characterized by intravascular thrombi formation and exhaustion of platelets and coagulation factors resulting in diffuse hemorrhage and multiple organ dysfunction.

Presentation of case

We present a case report of a previously healthy middle-aged patient who was treated by low anterior resection for rectal carcinoma and suddenly went into unexpected circulatory shock on the 7th postoperative day. Despite our resuscitation efforts, he succumbed to the disease. The postmortem examination showed findings consistent with DIC.

Discussion

The cause for DIC in this patient may be multifactorial. Sepsis, tumor-related factors and hereditary predisposition may have played a role. The role of blood components in treatment is not fully understood as they may worsen the inflammatory response.

Conclusion

DIC can be the presenting sign of unrecognized sepsis and it can occur in all surgical patients. Even with prompt treatment, the disease can have a fatal course.

The association of coagulation indicators with in-hospital mortality and 1-year mortality of patients with sepsis at ICU admissions: A retrospective cohort study

BACKGROUND

Coagulation activation is the host's response to pathogens during sepsis and is considered to be one of the reasons for tissue damage and multiple organ failure. This study is designed to evaluate whether the alterations of coagulation indicators are related to in-hospital mortality and 1-year mortality of patients with sepsis.

METHOD

Data of all 2258 patients were extracted from the database Multiparameter Intelligent Monitoring in Intensive Care III (MIMIC III). The relationship between the in-hospital mortality of patients with sepsis and coagulation indicators was analyzed with a receiver operating characteristic (ROC) curve analysis and logistic regression model. Effects of coagulation indicators on patients' 1-year mortality were determined by using a Cox hazard regression model, and clinical experience or quintiles were used to classify the activated partial thromboplastin time (APTT) to determine the cutoff values to explore segmentation effects.

RESULT

International normalized ratio (INR) was positively associated with hospital mortality of patients with sepsis after adjusting confounders with an odds ratio (OR) of 1.86 [95% confidence interval (CI), 1.37-2.52], and a hazard ratio (HR) of 1.465[95%CI(1.24-1.74)] for 1-year mortality, respectively. 1-year mortality of patients with sepsis demonstrated a U-shaped relationship with APTT, ranging from 25 to 37, indicating the lowest risk. The adjusted HR (95% CI) values for 1-year mortality of septic patients with risk values <25 and >37 were 1.493 (1.02, 2.19) and 1.379 (1.06, 1.79), respectively.

CONCLUSION

Increased INR in critically ill septic patients is related to greater in-hospital mortality and 1-year mortality. A U-shaped relationship was found between APTT and 1-year mortality of patients with sepsis.

Activated Clotting Time as a Marker of Inflammation in Hospitalized Patients

Inflammation and coagulation pathways are implicated in circulatory disease, but their interaction has not been completely deciphered yet. In this study, we investigated the association of coagulation and inflammation indices (activated clotting time [ACT], C-reactive protein, neutrophils) in hospitalized patients. Blood samples were drawn from consecutive patients at admission and at 48 hours for the assessment of the aforementioned parameters (n = 63). Healthy controls matched for sex and age were also examined (n = 39). Activated clotting time positively correlated with CRP on admission (r = 0.354, P = .005), while the correlation was more robust on the second day (r = 0.775, P < .001). Activated clotting time was significantly more prolonged in patients with abnormal CRP or abnormal absolute neutrophil count compared to patients with normal inflammatory markers (U = 55.0, P < .001 and U = 310.5, P = .035, respectively). At 48 hours, a positive relationship was observed between ACT and relative percentage of neutrophils (r = 0.358, P = .004). These findings suggest a link between ACT and inflammation indices for the first time in humans. Further research is needed to determine whether these interrelations can be used to improve patient management.

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.

Use of Viscoelastography in Malignancy-Associated Coagulopathy and Thrombosis: A Review

The relationship between malignancy and coagulopathy is one that is well documented yet incompletely understood. Clinicians have attempted to quantify the hypercoagulable state produced in various malignancies using common coagulation tests such as prothrombin time, activated partial thromboplastin time, and platelet count; however, due to these tests' focus on individual aspects of coagulation during one specific time point, they have failed to provide clinicians the complete picture of malignancy-associated coagulopathy (MAC). Viscoelastic tests (VETs), such as thromboelastography (TEG) and rotational thromboelastometry (ROTEM), are whole blood analyses that have the advantage of providing information related to the cumulative effects of plasma clotting factors, platelets, leukocytes, and red cells during all stages of the coagulation and fibrinolytic processes. VETs have gained popularity in the care of trauma patients to objectively measure trauma-induced coagulopathy (TIC), but the utility of VETs remains yet unrealized in many other medical specialties. The authors discuss the similarities and differences between TIC and MAC, and propose a mechanism for the hypercoagulable state of MAC that revolves around the thrombomodulin-thrombin complex as it switches between activating the protein C anticoagulation pathway or the thrombin activatable fibrinolysis inhibitor coagulation pathway. Additionally, they review the current literature on the use of TEG and ROTEM in patients with various malignancies. Although limited research is currently available, early results demonstrate the utility of both TEG and ROTEM in the prediction of hypercoagulable states and thromboembolic complications in oncologic patients.

Thrombomodulin alfa prevents the decrease in platelet aggregation in rat models of disseminated intravascular coagulation

INTRODUCTION

Disseminated intravascular coagulation (DIC), a deadly complication characterized by uncontrolled hypercoagulation, causes a decrease in the platelet count and impairs platelet aggregation. Thrombomodulin (TM) alfa, a recombinant human soluble TM, reduces hypercoagulation in DIC patients. However, the effects of TM alfa on impaired platelet aggregation remain to be determined. In this study, we aim to investigate the effects of TM alfa on platelet aggregation using lipopolysaccharide (LPS)-induced and tissue factor (TF)-induced DIC rat models.

MATERIALS AND METHODS

Sprague-Dawley rats were administered TF or LPS intravenously, with or without TM alfa before the injection. Six hours after LPS injection or 1 h after TF infusion, blood samples were obtained, and platelet-rich plasma was prepared. Collagen or adenosine diphosphate-induced platelet aggregation was measured using an aggregometer. In the other experiments, platelets were transfused 1 h after the TF infusion. Five minutes after transfusion, collagen-induced platelet aggregation was also measured.

RESULTS

The amplitude of platelet aggregation in platelet-rich plasma was decreased in LPS- and TF-treated rats. TM alfa inhibited the decrease in platelet aggregation in a dose-dependent manner. The washed platelet aggregation amplitude was not decreased in TF-treated rats. Suspension of normal platelets in plasma obtained from TF-treated rats reduced platelet aggregation. Platelet transfusion for TF-treated rats increased the platelet count but was unable to improve platelet aggregation.

CONCLUSIONS

TM alfa attenuated impairment of platelet aggregation in LPS- and TF-induced DIC rat models. The changes in plasma composition played a role in the decrease of platelet aggregation in TF-treated rats.

Platelet function in disseminated intravascular coagulation: A systematic review

Disseminated intravascular coagulation (DIC) has a well-examined pathophysiology, yet some essential elements remain undetermined. During DIC, platelets play an important role in the development of micro thrombosis, but changes in platelet function parameters and their association with development of DIC have not been established. The present systematic review investigated reported associations between platelet function (activation, aggregation, and adhesion) and DIC. We performed a literature search in Embase and PubMed, following the Preferred Reporting Items for Systematic and Meta-Analyses (PRISMA) guidelines. In total, 22 articles were included; 14 human studies, seven animal studies, and one with both human and animal subjects. Platelet activation markers were generally reported to be higher in both DIC patients and animals with DIC than healthy controls, and higher among patients with DIC than patients without DIC. Six human and six animal studies investigated platelet aggregation, which were overall reported to be lower in DIC than in non-DIC or in healthy controls in both human and animal studies. Platelet aggregation was deemed to be confounded by low platelet counts, which are known to affect platelet aggregation analyses even within the reference interval. In conclusion, platelet activation analyses showed promise in diagnosis of DIC, but semi-automatization and standardization are warranted before these can be implemented in daily clinical practice. Changes in platelet aggregation analyses during DIC remain inconclusive, and further studies including adjustment for low platelet count are needed to clarify the role of platelet aggregation in DIC.

Routine coagulation tests on ICU admission are associated with mortality in sepsis: an observational study

BACKGROUND

Low platelet count on admission to an intensive care unit (ICU) is associated with increased mortality and is thus included in some severity scoring systems such as the simplified acute physiologic score 3 (SAPS 3); however it is unclear whether other routine coagulation tests also predict mortality. The purpose of this retrospective single-centre study was to investigate whether activated partial thromboplastin time (APTT) or prothrombin time - international normalized ratio (PT-INR) measured on admission to the ICU in patients with severe sepsis or septic shock may be associated with mortality independent of SAPS 3 score.

METHODS

All patients admitted to a tertiary general ICU from 2007 to 2014 diagnosed with severe sepsis or septic shock were eligible. Results from APTT and PT-INR within 1.5 h of admission as well as SAPS 3 were used as independent variables in a Cox regression.

RESULTS

Of total 5485 ICU admissions during the study period we identified 647 unique patients with severe sepsis or septic shock. APTT and PT-INR were found to correlate significantly with mortality with a hazard ratio (HR) of 1.014 [95% confidence interval of HR (1.006-1.023)] for APTT and 1.422 (1.117-1.811) for PT-INR. HR for SAPS 3 was 1.036 (1.028-1.044).

CONCLUSION

Activated partial thromboplastin time prolongation and raised PT-INR on ICU admission in patients with severe sepsis or septic shock is associated with increased mortality independent of SAPS 3 score. This indicates that APTT prolongation and PT-INR increase represents morbidity that is not accounted for in SAPS 3.

Hyperfibrinolysis and Hypofibrinogenemia Diagnosed With Rotational Thromboelastometry in Dogs Naturally Infected With Angiostrongylus vasorum

Background

The pathomechanism of Angiostrongylus vasorum infection‐associated bleeding diathesis in dogs is not fully understood.

Objective

To describe rotational thromboelastometry (ROTEM) parameters in dogs naturally infected with A. vasorum and to compare ROTEM parameters between infected dogs with and without clinical signs of bleeding.

Animals

A total of 21 dogs presented between 2013 and 2016.

Methods

Dogs with A. vasorum infection and ROTEM evaluation were retrospectively identified. Thrombocyte counts, ROTEM parameters, clinical signs of bleeding, therapy, and survival to discharge were retrospectively retrieved from patient records and compared between dogs with and without clinical signs of bleeding.

Results

Evaluation by ROTEM showed hyperfibrinolysis in 8 of 12 (67%; 95% CI, 40–86%) dogs with and 1 of 9 (11%; 95% CI, 2–44%) dogs without clinical signs of bleeding (P = .016). Hyperfibrinolysis was associated with severe hypofibrinogenemia in 6 of 10 (60%; 95% CI, 31–83%) of the cases. Hyperfibrinolysis decreased or resolved after treatment with 10–80 mg/kg tranexamic acid. Fresh frozen plasma (range, 14–60 mL/kg) normalized follow‐up fibrinogen function ROTEM (FIBTEM) maximal clot firmness in 6 of 8 dogs (75%; 95% CI, 41–93%). Survival to discharge was 67% (14/21 dogs; 95% CI, 46–83%) and was not different between dogs with and without clinical signs of bleeding (P = .379).

Conclusion and Clinical Importance

Hyperfibrinolysis and hypofibrinogenemia were identified as an important pathomechanism in angiostrongylosis‐associated bleeding in dogs. Hyperfibrinolysis and hypofibrinogenemia were normalized by treatment with tranexamic acid and plasma transfusions, respectively.

Thromboelastometry-guided blood transfusion in septic shock complicated with disseminated intravascular coagulation: a case report

Approximately 25–50% of septic patients develop disseminated intravascular coagulation. The thromboelastometry evaluates whole blood clot formation and dissolution in real time and has been considered for management of bleeding in diverse clinical conditions. We present a case of thromboelastometry‐guided bleeding management of a septic shock patient with overt disseminated intravascular coagulation (DIC).