A prothrombotic coagulopathy is commonly found in critically ill COVID‐19 patients with acute respiratory distress syndrome (ARDS). A unique feature of COVID‐19 respiratory failure is a relatively ...preserved lung compliance and high Alveolar‐arterial oxygen gradient, with pathology reports consistently demonstrating diffuse pulmonary microthrombi on autopsy, all consistent with a vascular occlusive etiology of respiratory failure rather than the more classic findings of low‐compliance in ARDS. The COVID‐19 pandemic is overwhelming the world’s medical care capacity with unprecedented needs for mechanical ventilators and high rates of mortality once patients progress to needing mechanical ventilation, and in many environments including in parts of the United States the medical capacity is being exhausted. Fibrinolytic therapy has previously been used in a Phase 1 clinical trial that led to reduced mortality and marked improvements in oxygenation. Here we report a series of three patients with severe COVID‐19 respiratory failure who were treated with tissue plasminogen activator. All three patients had a temporally related improvement in their respiratory status, with one of them being a durable response.
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FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract Background Fibrinolysis is a physiologic process to maintain microvascular patency by breaking down excessive fibrin clot. Hyperfibrinolysis (HF) is associated with a doubling of mortality. ...Fibrinolysis shutdown (SD), an acute impairment of fibrinolysis, has been recognized as a risk factor for increased mortality. The purpose of this study was to assess the incidence and outcomes of fibrinolysis phenotypes in two urban trauma centers. Study Design Injured patients admitted 2010-2013, who were ≥18 years of age, had an injury severity score (ISS) >15 were included in the analysis. Admission fibrinolysis phenotypes were determined by the clot lysis at 30 minutes (LY30): SD ≤0.8%, physiologic 0.9-2.9%, HF ≥3%. Logistic regression was used to adjust for age, arrival blood pressure, ISS, mechanism, and facility. Results 2540 patients met inclusion. Median age was 39(IQR 26-55) and median ISS was 25(IQR 20-33) with a mortality rate of 21%. Fibrinolysis shutdown was the most common phenotype (46%) followed by physiologic (36%) and hyperfibrinolysis(18%). HF was associated with the highest death rate (34%), followed by SD(22%), and physiologic (14%, p<0.001). The risk of mortality remained increased for HF(OR=3.3, 95%C: 2.4-4.6, p<0.0001) and SD(OR 1.6 95%CI 1.3-2.1, p=0.0003) compared to physiologic when adjusting for age, ISS, mechanism, head injury, and blood pressure (AUROC=0.82, 95% CI 0.80-0.84). Conclusions Fibrinolysis SD is the most common phenotype upon admission and is associated with increased mortality. Moreover, these data provide additional evidence of distinct phenotypes of coagulation impairment and that individualized hemostatic therapy may be required.
The COVID-19 pandemic has introduced a global public health threat unparalleled in our history. The most severe cases are marked by ARDS attributed to microvascular thrombosis. Hypercoagulability, ...resulting in a profoundly prothrombotic state, is a distinct feature of COVID-19 and is accentuated by a high incidence of fibrinolysis shutdown. The aims of this review were to describe the manifestations of fibrinolysis shutdown in COVID-19 and its associated outcomes, review the molecular mechanisms of dysregulated fibrinolysis associated with COVID-19, and discuss potential implications and therapeutic targets for patients with severe COVID-19.
Low fibrinolytic activity has been associated with pathologic thrombosis and multiple-organ failure. Low fibrinolytic activity has two commonly associated terms, hypofibrinolysis and fibrinolysis ...shutdown. Hypofibrinolysis is a chronic state of lack of ability to generate an appropriate fibrinolytic response when anticipated. Fibrinolysis shutdown is the shutdown of fibrinolysis after systemic activation of the fibrinolytic system. There has been interchanging of these terms to describe critically ill patients in multiple settings. This is problematic in understanding the pathophysiology of disease processes related to these conditions. There is also a lack of research on the cellular mediators of these processes. The purpose of this article is to review the on and off mechanisms of fibrinolysis in the context of low fibrinolytic states to define the importance in differentiating hypofibrinolysis from fibrinolysis shutdown. In many clinical scenarios, the etiology of a low fibrinolytic state cannot be determined due to ambiguity if a preceding fibrinolytic activation event occurred. In this scenario, the term "low fibrinolytic activity" or "fibrinolysis resistance" is a more appropriate descriptor, rather than using assumptive of hypofibrinolysis and fibrinolysis shutdown, particularly in the acute setting of infection, injury, and surgery.
COVID-19 predisposes patients to a prothrombotic state with demonstrated microvascular involvement. The degree of hypercoagulability appears to correlate with outcomes; however, optimal criteria to ...assess for the highest-risk patients for thrombotic events remain unclear; we hypothesized that deranged thromboelastography measurements of coagulation would correlate with thromboembolic events.
Patients admitted to an ICU with COVID-19 diagnoses who had thromboelastography analyses performed were studied. Conventional coagulation assays, d-dimer levels, and viscoelastic measurements were analyzed using a receiver operating characteristic curve to predict thromboembolic outcomes and new-onset renal failure.
Forty-four patients with COVID-19 were included in the analysis. Derangements in coagulation laboratory values, including elevated d-dimer, fibrinogen, prothrombin time, and partial thromboplastin time, were confirmed; viscoelastic measurements showed an elevated maximum amplitude and low lysis of clot at 30 minutes. A complete lack of lysis of clot at 30 minutes was seen in 57% of patients and predicted venous thromboembolic events with an area under the receiver operating characteristic curve of 0.742 (p = 0.021). A d-dimer cutoff of 2,600 ng/mL predicted need for dialysis with an area under the receiver operating characteristic curve of 0.779 (p = 0.005). Overall, patients with no lysis of clot at 30 minutes and a d-dimer > 2,600 ng/mL had a venous thromboembolic event rate of 50% compared with 0% for patients with neither risk factor (p = 0.008), and had a hemodialysis rate of 80% compared with 14% (p = 0.004).
Fibrinolysis shutdown, as evidenced by elevated d-dimer and complete failure of clot lysis at 30 minutes on thromboelastography predicts thromboembolic events and need for hemodialysis in critically ill patients with COVID-19. Additional clinical trials are required to ascertain the need for early therapeutic anticoagulation or fibrinolytic therapy to address this state of fibrinolysis shutdown.
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Trauma remains a leading cause of death worldwide, and most early preventable deaths in both the civilian and military settings are due to uncontrolled hemorrhage, despite paradigm advances in modern ...trauma care. Combined tissue injury and shock result in hemostatic failure, which has been identified as a multidimensional molecular, physiologic and clinical disorder termed trauma‐induced coagulopathy (TIC). Understanding the biology of TIC is of utmost importance, as it is often responsible for uncontrolled bleeding, organ failure, thromboembolic complications, and death. Investigations have shown that TIC is characterized by multiple phenotypes of impaired hemostasis due to altered biology in clot formation and breakdown. These coagulopathies are attributable to tissue injury and shock, and encompass underlying endothelial, immune and inflammatory perturbations. Despite the recognition and identification of multiple mechanisms and mediators of TIC, and the development of targeted treatments, the mortality rates and associated morbidities due to hemorrhage after injury remain high. The purpose of this review is to examine the past and present understanding of the multiple distinct but highly integrated pathways implicated in TIC, in order to highlight the current knowledge gaps and future needs in this evolving field, with the aim of reducing morbidity and mortality after injury.
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FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Viscoelastic assays, such as thrombelastography (TEG) and rotational thrombelastometry (ROTEM), have emerged as point-of-care tools that can guide the hemostatic resuscitation of bleeding injured ...patients. This article describes the role of TEG in contemporary trauma care by explaining this assay's methodology, clinical applications, and result interpretation through description of supporting studies to provide the reader with an evidence-based user's guide. Although TEG and ROTEM are assays based on the same viscoelastic principle, this article is focused on data supporting the use of TEG in trauma, because it is available in trauma centers in North America; ROTEM is mostly available in Europe.
Despite over a half-century of recognizing fibrinolytic abnormalities after trauma, we remain in our infancy in understanding the underlying mechanisms causing these changes, resulting in ineffective ...treatment strategies. With the increased utilization of viscoelastic hemostatic assays (VHAs) to measure fibrinolysis in trauma, more questions than answers are emerging. Although it seems certain that low fibrinolytic activity measured by VHA is common after injury and associated with increased mortality, we now recognize subphenotypes within this population and that specific cohorts arise depending on the specific time from injury when samples are collected. Future studies should focus on these subtleties and distinctions, as hypofibrinolysis, acute shutdown, and persistent shutdown appear to represent distinct, unique clinical phenotypes, with different pathophysiology, and warranting different treatment strategies.