Hypercoagulability in critically ill patients with COVID 19, an observational prospective study

[Point of care coagulation diagnostics-Absolutely necessary or only a reasonable supplement?]

Point of care (POC) coagulation diagnostics have become an integral part of clinical patient care. In particular, the strengths of POC viscoelastometry (VET) lie not only in the rapid availability of test results but also in the fact that VET provides insights into coagulation that cannot be detected by standard laboratory tests. The relevance of POC-VET in the optimal management of patients with acutely acquired bleeding disorders, such as trauma-induced coagulopathy, is now unquestioned and is also reflected in the corresponding guidelines; however, VET also provides important information about fibrinolysis and fibrinolytic activity and in combination with other laboratory values can possibly also be sensitive for prothrombotic coagulation disorders. Therefore, POC-VET is increasingly being used in intensive care medicine. The use of POC diagnostics is not subject to the same standards as central laboratory testing. In order to maintain high quality and avoid harming patients, the requirements for medical device manufacturers in particular have been increased as part of the in vitro diagnostic reagents (IVDR) regulations, which places high demands on quality management in particular. The variety of POC devices and the lack of comparability between them remains an unsolved problem. It should be critically discussed to what extent medical device manufacturers and pharmaceutical companies could be legally required to keep unique and urgently needed technologies on the market, especially if no comparable alternatives will be available in the foreseeable future. Overall, from today's perspective, the use of POC coagulation diagnostics is essential for optimal patient care.

Clustering based on renal and inflammatory admission parameters in critically ill patients admitted to the ICU

INTRODUCTION

The COVID-19 pandemic has been associated with significant variability in acute kidney injury (AKI) incidence, leading to concerns regarding patient heterogeneity. The study's primary objective was a cluster analysis, to identify homogeneous subgroups of patients (clusters) using baseline characteristics, including inflammatory biomarkers. The secondary objectives were the comparisons of MAKE-90 and mortality between the different clusters at three months.

METHODS

This retrospective single-center study was conducted in the Medical Intensive Care Unit of the University Hospital of Clermont-Ferrand, France. Baseline data, clinical and biological characteristics on ICU admission, and outcomes at day 90 were recorded. The primary outcome was the risk of major adverse kidney events at 90 days (MAKE-90). Clusters were determined using hierarchical clustering on principal components approach based on admission characteristics, biomarkers and serum values of immune dysfunction and kidney function.

RESULTS

It included consecutive adult patients admitted between March 20, 2020 and February 28, 2021 for severe COVID-19. A total of 149 patients were included in the study. Three clusters were identified of which two were fully described (cluster 3 comprising 2 patients). Cluster 1 comprised 122 patients with fewer organ dysfunctions, moderate immune dysfunction, and was associated with reduced mortality and a lower incidence of MAKE-90. Cluster 2 comprised 25 patients with greater disease severity, immune dysfunction, higher levels of suPAR and L-FABP/U Creat, and greater organ support requirement, incidence of AKI, day-90 mortality and MAKE-90.

CONCLUSIONS

This study identified two clusters of severe COVID-19 patients with distinct biological characteristics and renal event risks. Such clusters may help facilitate the identification of targeted populations for future clinical trials. Also, it may help to understand the significant variability in AKI incidence observed in COVID-19 patients.

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.

Persistent hypofibrinolysis in severe COVID-19 associated with elevated fibrinolysis inhibitors activity

Hypercoagulability and reduced fibrinolysis are well-established complications associated with COVID-19. However, the timelines for the onset and resolution of these complications remain unclear. The aim of this study was to evaluate, in a cohort of COVID-19 patients, changes in coagulation and fibrinolytic activity through ROTEM assay at different time points during the initial 30 days following the onset of symptoms in both mild and severe cases. Blood samples were collected at five intervals after symptoms onset: 6-10 days, 11-15 days, 16-20 days, 21-25 days, and 26-30 days. In addition, fibrinogen, plasminogen, PAI-1, and alpha 2-antiplasmin activities were determined. Out of 85 participants, 71% had mild COVID-19. Twenty uninfected individuals were evaluated as controls. ROTEM parameters showed a hypercoagulable state among mild COVID-19 patients beginning in the second week of symptoms onset, with a trend towards reversal after the third week of symptoms. In severe COVID-19 cases, hypercoagulability was observed since the first few days of symptoms, with a tendency towards reversal after the fourth week of symptoms onset. A hypofibrinolytic state was identified in severe COVID-19 patients from early stages and persisted even after 30 days of symptoms. Elevated activity of PAI-1 and alpha 2-antiplasmin was also detected in severe COVID-19 patients. In conclusion, both mild and severe cases of COVID-19 exhibited transient hypercoagulability, reverted by the end of the first month. However, severe COVID-19 cases sustain hypofibrinolysis throughout the course of the disease, which is associated with elevated activity of fibrinolysis inhibitors. Persistent hypofibrinolysis could contribute to long COVID-19 manifestations.

Mechanisms of endothelial activation, hypercoagulation and thrombosis in COVID-19: a link with diabetes mellitus

Early since the onset of the COVID-19 pandemic, the medical and scientific community were aware of extra respiratory actions of SARS-CoV-2 infection. Endothelitis, hypercoagulation, and hypofibrinolysis were identified in COVID-19 patients as subsequent responses of endothelial dysfunction. Activation of the endothelial barrier may increase the severity of the disease and contribute to long-COVID syndrome and post-COVID sequelae. Besides, it may cause alterations in primary, secondary, and tertiary hemostasis. Importantly, these responses have been highly decisive in the evolution of infected patients also diagnosed with diabetes mellitus (DM), who showed previous endothelial dysfunction. In this review, we provide an overview of the potential triggers of endothelial activation related to COVID-19 and COVID-19 under diabetic milieu. Several mechanisms are induced by both the viral particle itself and by the subsequent immune-defensive response (i.e., NF-κB/NLRP3 inflammasome pathway, vasoactive peptides, cytokine storm, NETosis, activation of the complement system). Alterations in coagulation mediators such as factor VIII, fibrin, tissue factor, the von Willebrand factor: ADAMST-13 ratio, and the kallikrein-kinin or plasminogen-plasmin systems have been reported. Moreover, an imbalance of thrombotic and thrombolytic (tPA, PAI-I, fibrinogen) factors favors hypercoagulation and hypofibrinolysis. In the context of DM, these mechanisms can be exacerbated leading to higher loss of hemostasis. However, a series of therapeutic strategies targeting the activated endothelium such as specific antibodies or inhibitors against thrombin, key cytokines, factor X, complement system, the kallikrein-kinin system or NETosis, might represent new opportunities to address this hypercoagulable state present in COVID-19 and DM. Antidiabetics may also ameliorate endothelial dysfunction, inflammation, and platelet aggregation. By improving the microvascular pathology in COVID-19 and post-COVID subjects, the associated comorbidities and the risk of mortality could be reduced.

Whole blood viscoelastic testing profile and mortality in patients hospitalized with acute COVID-19 pneumonia: A systematic review and meta-analysis

BACKGROUND

Several studies have evaluated the possible association between whole blood viscoelastic testing (VET) parameters in patients hospitalized for acute Coronavirus disease 2019 (COVID-19) pneumonia and mortality. A few studies found no significant differences between survivors and non-survivors, though other studies identified potential predictors of COVID-19-related mortality. We conducted a systematic review and meta-analysis of the literature to evaluate the possible association between standard thromboelastometry/graphy parameters and mortality in patients hospitalized for acute COVID-19 pneumonia.

METHODS

Relevant studies were searched through MEDLINE, EMBASE, and Google Scholar from their inception until 15th June 2023. We aimed to identify any study including: i) adults admitted to intensive care units (ICU) or medicine wards (MW) for acute COVID-19 pneumonia; ii) viscoelastic testing; iii) mortality.

RESULTS

We included 13 studies: nine prospective and four retrospective, 231 (30.4 %) non-survivors and 528 (69.6 %) survivors. Mortality rates ranged from 12.8 % to 67.5 %. The studies using the TEG apparatus found a significant difference in K time in the Kaolin test among survivors vs. non-survivors (mean difference [MD] 0.20, 95 % confidence interval [CI] 0.12, 0.28, I2 0%). The studies using the rotational thromboelastometry apparatus found a significant difference in CT-INTEM (MD -17.14, 95 % CI -29.23, -5.06, I2 0%) and LI60-EXTEM (MD -1.00, 95 % CI -1.00, -1.00, I2 0%) assays among survivors vs. non-survivors.

CONCLUSION

We identified no specific hypercoagulable or hypocoagulable profile associated with mortality in patients with COVID-19-related pneumonia. Large prospective studies are needed to explore the possible prognostic role of VET in this subset of patients.