Thrombocytopenia is the most common haemostatic disorder in patients admitted to Intensive Care Units (ICUs). The mechanisms contributing to a decrease in the platelet count in critically ill patients are multifactorial, among which sepsis and trauma are the most frequent. A differential diagnosis of profound thrombocytopenia is crucial for effective treatment. A low platelet count is a strong independent predictor of morbidity and mortality because it is associated with life-threatening bleeding or thrombosis. This article aims to outline the definition and pathophysiology of thrombocytopenia and present a three-step algorithm of the clinical management of this haemostatic disorder. Thrombocytopenia is the most common haemostatic disorder in patients admitted to Intensive Care Units (ICUs). The mechanisms contributing to a decrease in the platelet count in critically ill patients are multifactorial, among which sepsis and trauma are the most frequent. A differential diagnosis of profound thrombocytopenia is crucial for effective treatment. A low platelet count is a strong independent predictor of morbidity and mortality because it is associated with life-threatening bleeding or thrombosis. This article aims to outline the definition and pathophysiology of thrombocytopenia and present a three-step algorithm of the clinical management of this haemostatic disorder.

Patients hospitalized in the intensive care unit (ICU) due to the COVID-19 experience a high incidence (up to 43%) of venous thromboembolic events. While laboratory findings in COVID-19-associated coagulopathy (CAC) show increased D-dimer and fibrinogen levels, the abnormalities in standard coagulation tests and platelet count are minimal. Recent studies suggest contribution of fibrinolysis shutdown to this phenomenon. Endothelial injury and alteration of its antithrombotic activity can lead to micro- and macrovascular thrombosis in the lungs, occurrence of which is associated with poor clinical outcome in critically ill patients with COVID-19. Additionally, the hypercoagulability induced by activation of coagulation pathways during the immune response to SARS-CoV-2 infection contributes to impaired organ perfusion. This, alongside with hypoxemia, leads to multiorgan failure. Various diagnostic regimens, some of which include global assays of haemostasis, are currently being published and discussed. Numerous guidelines and recommendations of scientific societies and groups of specialists have been published. However, there is no single optimal algorithm for anticoagulation treatment and monitoring specific to the ICU patients with COVID-19. The authors have attempted to summarize the data related to CAC and thrombotic disease and develop an algorithm consistent with the latest clinical practice guideline recommendations.

Introduction: Infection with SARS-CoV-2 in its most severe form leads to acute respiratory distress syndrome requiring mechanical ventilation under the conditions of the Intensive Care Unit (ICU). The state of hypercoagulation described in COVID-19 may deepen respiratory failure, leading to increased mortality. The aim of the presented study is to characterise the haemostatic profile based on the results of clotting system parameters and risk assessment of thromboembolic complications of patients hospitalised in the ICU.Material and methods: This retrospective study covered the first 10 adult patients hospitalised in the ICU of the Hospital for Infectious Diseases in Warsaw in the second quarter of 2020. Demographic, clinical and laboratory parameters of the coagulation system and the risk of thromboembolic complications were assessed. Well known criteria of haemostatic disorders were used to classify the observed derangements.Results: The most frequently observed deviations in the coagulation system were high concentrations of D-dimer and fibrinogen. In select cases the clotting time was prolonged. No severe thrombocytopenia was observed. All patients presented a high risk of thromboembolic complications as assesed by the Padua score. The observed clotting abnormalities did not meet the criteria for DIC (disseminated intravascular coagulation) and SIC (sepsis-induced coagulopathy) diagnosis.Conclusions: The main elements of coagulopathy that were observed in our cases differ from those usually seen in patients with recognised sepsis. The unique haemostatic profile of COVID-19 patients treated in the ICU has been described as CAC (COVID-19-associated coagulopathy).

Platelets play an essential role in haemostasis. Assessment of their function is vital for anaesthesiologists evaluating haemostatic potential, especially during emergency operations. The monitoring of platelets function had been implemented into the European recommendations for management of perioperative and posttraumatic bleeding. One of the diagnostic methods described in the recommendations is multiple electrode aggregometry. As antiplatelet therapy becomes more widely used in modern medicine, this method, in contrast to standard laboratory tests, can significantly help to identify patients with drug-induced thrombocytopaty. The aggregometry enables prompt evaluation of the platelets aggregation which is very useful for everyday decision-making in goal-directed hemostatic therapy. Platelets play an essential role in haemostasis. Assessment of their function is vital for anaesthesiologists evaluating haemostatic potential, especially during emergency operations. The monitoring of platelets function had been implemented into the European recommendations for management of perioperative and posttraumatic bleeding. One of the diagnostic methods described in the recommendations is multiple electrode aggregometry. As antiplatelet therapy becomes more widely used in modern medicine, this method, in contrast to standard laboratory tests, can significantly help to identify patients with drug-induced thrombocytopaty. The aggregometry enables prompt evaluation of the platelets aggregation which is very useful for everyday decision-making in goal-directed hemostatic therapy.

Backgorund: Multifactorial haemostasis disorders are typical of patients with end-stage renal disease (ESRD) on chronic haemodialysis (HD). Thromboelastometry and impedance aggregometry allow for a comprehensive assessment of clot formation, lysis, and platelet (PLT) function. This study aims to determine the haemostatic profile in a group of patients with ESRD on chronic, interrupted dialysis, especially in terms of PLT function and the impact of in vitro fibrinogen concentrate supplementation on clot properties.Methods: A total of 22 patients on chronic HD and 22 healthy controls (HC) were enrolled in the prospective study with a control group. Global haemostasis assays (GHA) were used to describe the haemostasis profile and to assess the effect of fibrinogen concentrate supplementation on improving clot quality.Results: Despite the lack of considerable differences in the number of PLTs, there was a significantly lower potential of PLT aggregation in the HD group (922 ±163 AU*min). A higher concentration of fibrinogen was also observed in this group which presented considerably higher maximum clot firmness (MCF) FIBTEM (22 ±5.3 mm). Clotting time (CT) EXTEM was also prolonged (72 ±23 s). No hyperfibrinolysis was reported. In vitro fibrinogen concentrate supplementation resulted in significant improvement in MCF FIBTEM (30 mm vs. 22 mm; P < 0.001). However, it also led to a deterioration in PLT aggregation as assessed by TRAPtest.Conclusions: The haemostasis profile of ESRD patients demonstrates a limited potential of PLT aggregation, with no improvement after fibrinogen addition.