Coagulopathy is not predictive of bleeding in patients with acute decompensation of cirrhosis and acute-on-chronic liver failure

Definitions, Etiologies, and Outcomes of Acute on Chronic Liver Failure: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Acute-on-chronic liver failure (ACLF) is a major public health concern. We aimed to assess the definitions, etiologic spectrum, organ failure (OF), and outcomes of ACLF globally.

METHODS

Three databases were searched for studies on ACLF from 1990 until September 2022. Information regarding definitions, acute precipitants, underlying chronic liver disease (CLD), OF, and mortality were extracted. Meta-analyses were performed for pooled prevalence rates (95% confidence interval [CI]) using random-effects model for each definition of ACLF.

RESULTS

Of the 11,451 studies identified, 114 articles (142 cohorts encompassing 210,239 patients) met the eligibility criteria. Most studies (53.2%) used the European Association for the Study of the Liver (EASL) definition, followed by Asia-Pacific Association for the Study of the Liver (APASL) (33.3%). Systemic infection was the major acute precipitant, and alcohol use was the major cause of CLD in EASL-defined studies, whereas alcohol was both the major acute precipitant and cause of CLD in APASL-defined studies. Liver failure was the major OF in APASL-based studies, whereas renal failure was predominant in EASL-based studies. Thirty-day mortality varied across definitions: APASL: 38.9%, 95% CI, 31.2%-46.9%; EASL: 47.9%, 95% CI, 42.2%-53.5%; and NACSELD: 52.2%, 95% CI, 51.9%-52.5%. Diagnostic overlap between definitions ranged from 7.7% to 80.2%. Meta-regression suggested that the World Health Organization region influenced 30-day mortality in studies using EASL definition.

CONCLUSIONS

Heterogeneity in the definition of ACLF proposed by different expert societies and regional preferences in its use result in differences in clinical phenotype and outcomes. A uniform definition would enhance the comparability and interpretation of global data.

Acute decompensation of cirrhosis versus acute-on-chronic liver failure: What are the clinical implications?

It is essential to identify the subgroup of patients who experience poorer outcomes in order to adapt clinical management effectively. In the context of liver disease, the earlier the identification occurs, the greater the range of therapeutic options that can be offered to patients. In the past, patients with acute decompensation (AD) of chronic liver disease were treated as a homogeneous group, with emphasis on identifying those at the highest risk of death. In the last 15 years, a differentiation has emerged between acute-on-chronic liver failure syndrome (ACLF) and AD, primarily due to indications that the latter is linked to a less favorable short-term prognosis. Nevertheless, the definition of ACLF varies among the different knowledge societies, making it challenging to assess its true impact compared with AD. Therefore, the purpose of this review is to provide a detailed analysis emphasizing the critical importance of identifying ACLF in the field of advanced liver disease. We will discuss the differences between Eastern and Western approaches, particularly in relation to the occurrence of liver failure and disease onset. Common characteristics, such as the dynamic nature of the disease course, will be highlighted. Finally, we will focus on two key clinical implications arising from these considerations: the prevention of ACLF before its onset and the clinical management strategies once it develops, including liver transplantation and withdrawal of care.

Whole blood thrombin generation shows a significant hypocoagulable state in patients with decompensated cirrhosis

BACKGROUND

Patients with cirrhosis have a normal to increased thrombin generation (TG) capacity in platelet-poor plasma (PPP). By reflecting the contribution of all circulating blood cells, whole blood (WB) TG may allow a more physiological assessment of coagulation.

OBJECTIVES

We compared WB-TG vs PPP-TG in patients with cirrhosis.

METHODS

Assessment of coagulation included routine tests, factor VIII, natural anticoagulants, PPP-TG, and WB-TG. TG assays were performed with and without thrombomodulin. Twenty-five healthy subjects were included as controls.

RESULTS

We included 108 patients (Child-Pugh A/B/C, 44/24/40). Compared with controls, patients had significantly lower platelet count, longer international normalized ratio, higher FVIII, and lower levels of protein C/S and antithrombin. Regarding thrombomodulin-modified TG assays, in compensated cirrhosis, both PPP-TG and WB-TG indicated an increased TG capacity, as reflected by an endogenous thrombin potential (ETP) significantly higher than controls. In contrast, in decompensated cirrhosis, PPP-TG indicated a hypercoagulable state with increased ETP, higher peak height, and shorter time-to-peak than controls, whereas WB-TG revealed a progressive impairment of TG kinetics and total capacity, ultimately resulting in a profound hypocoagulable state in patients with Child-Pugh C cirrhosis (ie, significant prolongation of lag time and time-to-peak with reduction of both ETP and peak height). In decompensated patients, bacterial infections and severity of anemia were associated with a further reduction of both ETP and peak height.

CONCLUSION

Compensated cirrhosis is associated with an increased TG capacity. In decompensated cirrhosis, contrary to PPP-TG, which indicates hypercoagulability, WB-TG shows a significant hypocoagulable state. The clinical value of these findings deserves further investigation.

Prevention of Venous Thromboembolism in Medical Patients with Thrombocytopenia or with Platelet Dysfunction: The Last 10 Years

Current guideline recommendations for primary prophylaxis of venous thromboembolism (VTE) are based on randomized clinical trials that usually exclude subjects at a potentially high risk of bleeding complications. For this reason, no specific guideline is available for thromboprophylaxis in hospitalized patients with thrombocytopenia and/or platelet dysfunction. However, except in patients with absolute contraindications to anticoagulant drugs, antithrombotic prophylaxis should always be considered, for example, in hospitalized cancer patients with thrombocytopenia, especially in those with multiple VTE risk factors. Low platelet number, platelet dysfunction, and clotting abnormalities are also very common in patients with liver cirrhosis, but these patients have a high incidence of portal venous thrombosis, implying that cirrhotic coagulopathy does not fully protect against thrombosis. These patients may benefit from antithrombotic prophylaxis during hospitalization. Patients hospitalized for COVID-19 need prophylaxis, but frequently experience thrombocytopenia or coagulopathy. In patients with antiphospholipid antibodies, a high thrombotic risk is usually present, even in the presence of thrombocytopenia. VTE prophylaxis in high-risk conditions is thus suggested in these patients. At variance with severe thrombocytopenia (< 50,000/mm3), mild/moderate thrombocytopenia (≥ 50,000/mm3) should not interfere with VTE prevention decisions. In patients with severe thrombocytopenia, pharmacological prophylaxis should be considered on an individual basis. Aspirin is not as effective as heparins in lowering the risk of VTE. Studies in patients with ischemic stroke demonstrated that thromboprophylaxis with heparins is safe in these patients also during antiplatelet treatment. The use of direct oral anticoagulants in the prophylaxis of VTE in internal medicine patients has been recently evaluated, but no specific recommendation exists for patients with thrombocytopenia. The need for VTE prophylaxis in patients on chronic treatment with antiplatelet agents should be evaluated after assessing the individual risk of bleeding complications. Finally, the selection of patients who require post-discharge pharmacological prophylaxis remains debated. New molecules currently under development (such as the inhibitors of factor XI) may contribute to improve the risk/benefit ratio of VTE primary prevention in this setting of patients.

The evolving knowledge on primary hemostasis in patients with cirrhosis: A comprehensive review

Patients with cirrhosis develop complex alterations in primary hemostasis that include both hypocoagulable and hypercoagulable features. This includes thrombocytopenia, multiple alterations of platelet function, and increased plasma levels of von Willebrand factor. Contrary to the historical view that platelet dysfunction in cirrhosis might be responsible for an increased bleeding tendency, the current theory posits a rebalanced hemostasis in patients with cirrhosis. Severe thrombocytopenia is not indicative of the bleeding risk in patients undergoing invasive procedures and does not dictate per se the need for pre-procedural prophylaxis. A more comprehensive and individualized risk assessment should combine hemostatic impairment, the severity of decompensation and systemic inflammation, and the presence of additional factors that may impair platelet function, such as acute kidney injury and bacterial infections. Although there are multiple, complex alterations of platelet function in cirrhosis, their net effect is not yet fully understood. More investigations evaluating the association between alterations of platelet function and bleeding/thrombosis may improve risk stratification in patients with decompensated cirrhosis. Besides hemostasis, the assessment of von Willebrand factor Ag and ADP-induced, whole-blood platelet aggregation normalized by platelet count (VITRO score and PLT ratio) are promising biomarkers to predict the risk of hepatic decompensation and survival in both compensated and decompensated patients. Further investigations into the in vivo interplay between platelets, circulating blood elements, and endothelial cells may help advance our understanding of cirrhotic coagulopathy. Here, we review the complex changes in platelets and primary hemostasis in cirrhosis and their potential clinical implications.

A combination of clot formation abnormalities in thromboelastometry has a high prognostic value in patients with acute-on-chronic liver failure

BACKGROUND

Global coagulation tests offer a better tool to assess procoagulant and anticoagulant pathways, fibrinolysis and clot firmness and evaluate more accurately coagulation defects compared to conventional coagulation tests. Their prognostic role in acute-on-chronic liver disease (ACLF) or acute decompensation (AD) has not been well established.

AIMS

To assess the properties and prognostic value of the coagulation profile measured by rotational thromboelastometry (ROTEM) in ACLF and AD.

METHODS

84 consecutive patients (35 ACLF and 49 AD) were prospectively studied. Twenty healthy persons matched for age and gender were used as controls. 'Hypocoagulable' or 'hypercoagulable' profiles on admission were assessed based on nine ROTEM parameters and mortality was recorded at 30 and 90 days.

RESULTS

Individual ROTEM parameters denoted significantly more hypocoagulability in patients compared to controls. 'Hypocoagulable' profile (defined as a composite of 4 or more ROTEM parameters outside the range) was associated with more severe liver disease assessed either as MELD or Child-Pugh scores ( P  < 0.001 for both) and higher 30-day mortality (Log-rank P  = 0.012). 'Hypocoagulable' profile (HR 3.160, 95% CI 1.003-9.957, P  = 0.049) and ACLF status (HR 23.786, 95% CI 3.115-181.614, P  = 0.002) were independent predictors of 30-day mortality, in multivariate model. A higher early mortality rate was shown in ACLF patients with 'hypocoagulable' phenotype compared to those without (Log-rank P  = 0.017). 'Hypocoagulable' profile was not associated with mortality in AD.

CONCLUSION

'Hypocoagulable' profile was associated with more advanced liver disease and higher short-term mortality in patients with ACLF.

Serial rotational thromboelastometry measurements show worsening hypocoagulability in acute-on-chronic liver failure and are associated with the severity of liver disease

Background

Viscoelastic tests are used to better understand the complex picture of hemostasis in cirrhosis. Limited data exist regarding the clinical relevance of rotational thromboelastometry (ROTEM) in acute-on-chronic liver failure (ACLF) or acute decompensation (AD). We examined the pattern and role of sequential observations of 9 ROTEM components in both ACLF and AD groups.

Method

ROTEM measurements were compared within and between groups at 3 time points: on admission (T1), at 24 h (T2) and 48 h post-admission (T3).

Results

Forty-two consecutive patients (22 ACLF, 20 AD) were included. ROTEM determinants exhibited significant hypocoagulable deterioration in ACLF but not in AD over the 3 time points in clot formation time (CFT)EXTEM (P=0.01), maximum clot firmnessEXTEM (P=0.014), CFTINTEM (P<0.001), and alphaINTEM (P=0.028). The sum of hypocoagulable determinants increased from T1 to T3 in ACLF (P=0.029), but remained stable in AD. Five ROTEM variables showed significant differences towards hypocoagulability in ACLF compared to AD at T3. A "hypocoagulable" profile was associated with more severe liver disease (P<0.001 for model for end-stage liver disease [MELD] or Child-Pugh scores) and higher 30- and 90-day mortality (log-rank P=0.001 and P=0.013, respectively) but no more bleeding episodes or transfusions. Two ROTEM variables displayed strong correlations with MELD at T1 and 7 at T3 (|r coefficient|>0.5).

Conclusions

ROTEM measurements indicated worsening hypocoagulability shortly post-admission compared to baseline in ACLF, but remained stable in AD. The hypocoagulable derangement was mostly correlated with the severity of liver disease and higher short-term mortality, but not more bleeding episodes.

How to assess hemostasis in patients with severe liver disease

Patients with advanced liver diseases frequently acquire profound alterations in their hemostatic system. Simultaneous changes in procoagulant and anticoagulant systems result in a reset in the hemostatic balance with a relatively neutral net effect, although there are notable hypocoagulable and hypercoagulable features in the hemostatic system in patients with liver disease. Laboratory and clinical studies have demonstrated that patients have a relatively well-preserved hemostatic system even though routine diagnostic tests of hemostasis (prothrombin time, platelet count) suggest a bleeding tendency. Routine diagnostic tests of hemostasis are unsuitable to assess the hemostatic status of patients with liver disease, as these tests are insensitive for the concurrent prohemostatic and antihemostatic changes in these patients. These tests are, however, frequently requested in patients with liver disease, as they are well established indicators of severity of liver disease. This paper will discuss commonly used diagnostic and research-type hemostatic tests and will outline how test results should be interpreted in patients with liver disease.

How to manage hemostasis in patients with liver disease during interventions

Patients with advanced chronic liver disease (CLD) often need procedures to both treat and prevent complications of portal hypertension such as ascites or gastrointestinal bleeding. Abnormal results for hemostatic tests, such as prolonged prothrombin time, international normalized ratio, and/or thrombocytopenia, are commonly encountered, raising concerns about increased bleeding risk and leading to transfusion to attempt to correct prior to interventions. However hemostatic markers are poor predictors of bleeding risk in CLD, and routine correction, particularly with fresh frozen plasma and routine platelet transfusions, should be avoided. This narrative review discusses the hemostatic management of patients with CLD using 2 case descriptions.

Review article: Emerging and current management of acute-on-chronic liver failure

BACKGROUND

Acute-on-chronic liver failure (ACLF) is a clinically and pathophysiologically distinct condition from acutely decompensated cirrhosis and is characterised by systemic inflammation, extrahepatic organ failure, and high short-term mortality.

AIMS

To provide a narrative review of the diagnostic criteria, prognosis, epidemiology, and general management principles of ACLF. Four specific interventions that are explored in detail are intravenous albumin, extracorporeal liver assist devices, granulocyte-colony stimulating factor, and liver transplantation.

METHODS

We searched PubMed and Cochrane databases for articles published up to July 2023.

RESULTS

Approximately 35% of hospital inpatients with decompensated cirrhosis have ACLF. There is significant heterogeneity in the criteria used to diagnose ACLF; different definitions identify different phenotypes with varying mortality. Criteria established by the European Association for the Study of the Liver were developed in prospective patient cohorts and are, to-date, the most well validated internationally. Systemic haemodynamic instability, renal dysfunction, coagulopathy, neurological dysfunction, and respiratory failure are key considerations when managing ACLF in the intensive care unit. Apart from liver transplantation, there are no accepted evidence-based treatments for ACLF, but several different approaches are under investigation.

CONCLUSION

The recognition of ACLF as a distinct entity from acutely decompensated cirrhosis has allowed for better patient stratification in clinical settings, facilitating earlier engagement with the intensive care unit and liver transplantation teams. Research priorities over the next decade should focus on exploring novel treatment strategies with a particular focus on which, when, and how patients with ACLF should be treated.

The Clinical Spectrum and Manifestations of Acute-on-Chronic Liver Failure

Acute-on-chronic liver failure (ACLF) is characterized by abrupt decompensation in a patient with chronic liver disease with extrahepatic organ dysfunction and is implicated in an increased risk of mortality. ACLF may be present in approximately 20% to 40% of hospitalized cirrhosis. There are several diagnostic scoring systems for ACLF; one defined by the North American Consortium for Study of End-stage Liver Disease is the presence of acutely decompensated cirrhosis complicated by failure of two or more organ systems: circulatory, renal, neurological, coagulopathy, and/or pulmonary.

To TIPS or Not to TIPS in High Risk of Variceal Rebleeding and Acute-on-Chronic Liver Failure

Variceal bleeding is a consequence of severe portal hypertension in patients with liver cirrhosis. Although the rate of bleeding has decreased over time, variceal bleeding in the presence of acute-on-chronic liver failure (ACLF) carries a high risk of treatment failure and short-term mortality. Treatment and/or removal of precipitating events (mainly bacterial infection and alcoholic hepatitis) and decrease of portal pressure may improve outcome of patients with acute decompensation or ACLF. Transjugular intrahepatic portosystemic shunts (TIPSs), especially in the preemptive situation, have been found to efficiently control bleeding, prevent rebleeding, and reduce short-term mortality. Therefore, TIPS placement should be considered as an option in the management of ACLF patients with variceal bleeding.

Vascular liver diseases: A sex-oriented analysis of the literature

Vascular liver diseases are an heterogenous group of diseases that collectively represent an important health issue in the field of liver diseases. This narrative review was elaborated by the Special Interest Group (SIG) "Gender in Hepatology" of the Italian Association for the Study of the Liver (AISF). We aimed to review the current knowledge regarding the potential role of biological sex in patients with vascular liver diseases such as splanchnic vein thrombosis, hepatic vein thrombosis, porto-sinusoidal vascular disorder, and hereditary hemorrhagic telangiectasia. As vascular liver diseases commonly affect young individuals, including women in childbearing age, we also included a specific section on the management of pregnancy in these challenging patients.

Severity of systemic inflammation is the main predictor of ACLF and bleeding in individuals with acutely decompensated cirrhosis

BACKGROUND & AIMS

Hypercoagulability and hypofibrinolysis in acutely decompensated cirrhosis (AD) may be implicated in disease progression and haemostatic complications. We conducted a prospective study to: (1) characterise haemostatic alterations in AD; (2) evaluate whether such alterations can predict acute-on-chronic liver failure (ACLF) and bleeding/thrombosis.

METHODS

Hospitalised individuals with AD were prospectively recruited and underwent an extensive haemostatic profiling including coagulation factors, thrombomodulin-modified thrombin generation assay with evaluation of endogenous thrombin potential (ETP; marker for plasmatic hypercoagulability), fibrinolytic factors, and plasmin-antiplasmin complex (fibrinolysis activation marker). Inflammation severity was assessed by C-reactive protein (CRP). In part 1 of the study, we compared haemostasis in AD vs. controls (stable decompensated and compensated cirrhosis). In part 2 of the study, we prospectively followed individuals with AD for 1 year and investigated predictors of ACLF and bleeding/thrombosis.

RESULTS

A total of 169 individuals with AD were recruited (median model for end-stage liver disease score 20; CLIF-C AD 54). Compared with controls, AD was associated with more pronounced hypercoagulability (ETP: 871 vs. 750 vs. 605 nmol/L per min; p <0.0001), without differences in fibrinolysis activation. During follow-up, 55 individuals developed ACLF. CLIF-C AD, CRP, and Child-Pugh were independently associated with ACLF. A predictive model combining these variables (Padua model) accurately identified individuals at higher risk of ACLF (AUROC 0.857; 95% CI 0.798-0.915; sensitivity 74.5%, specificity 83.3%). Notably, CRP and progression to ACLF, but not baseline coagulopathy, were associated with bleeding (n = 11); CRP and antifibrinolytic factor PAI-1 >50 ng/ml were associated with thrombosis (n = 14). The prognostic value of the Padua model was validated in an independent, bicentric European cohort (N = 301).

CONCLUSIONS

Inflammation severity, and not coagulopathy, is the most important predictor of ACLF and bleeding in AD. The Padua model can be used to identify individuals with AD at risk of ACLF.

IMPACT AND IMPLICATIONS

A better understanding of haemostasis in individuals with acutely decompensated cirrhosis may help to identify those at higher risk of progression and complications. In this prospective study, we found no significant association between alterations of haemostasis and cirrhosis progression, indicating that the assessment of haemostatic alterations is not useful to identify those at risk. However, we found that C-reactive protein (a simple blood test that reflects severity of inflammation) and severity of chronic liver disease itself (as assessed by specific scores) were associated with cirrhosis progression and development of bleeding complications. Therefore, we developed a simple predictive model - based on C-reactive protein and liver disease scores - that, if validated by independent studies, could be used in clinical practice to assist physicians in identifying individuals with decompensated cirrhosis at higher risk of disease progression and death (i.e. in whom to consider an expedited evaluation for liver transplantation).

Anticoagulant therapy for splanchnic vein thrombosis: recent updates for patients with liver cirrhosis

INTRODUCTION

Liver cirrhosis is accompanied by several hemostatic alterations, which contribute to the current theory of "rebalanced hemostasis." Splanchnic vein thrombosis (SVT) is a frequent complication of liver cirrhosis (17-26% of the cirrhotic patients), and liver cirrhosis is a common risk factor for SVT (24-28% of SVT cases).

AREAS COVERED

This narrative review aims to describe the current state of the art on the anticoagulant treatment of cirrhotic SVT, with a particular focus on the possible role of the direct oral anticoagulants (DOACs) and recent guidelines on this topic.

EXPERT OPINION

Early anticoagulant therapy is recommended in cirrhotic patients with acute SVT, to obtain vessel recanalization and decrease the rates of portal hypertension-related complications. Gastroesophageal varices do not represent a contraindication to anticoagulation, if adequate prophylaxis of variceal bleeding is established, and varices band ligation can be safely performed without the need to stop the anticoagulant treatment. The conventional treatment of cirrhotic SVT consisted of low molecular weight heparin, as initial treatment of choice, eventually followed by vitamin K antagonists, but the DOACs can be considered as a reasonable alternative in patients with compensated liver cirrhosis.

Haemostasis in cirrhosis: Understanding destabilising factors during acute decompensation

Hospitalised patients with decompensated cirrhosis are in a rebalanced haemostatic state due to a parallel decline in both pro- and anti-haemostatic pathways. However, this rebalanced haemostatic state is highly susceptible to perturbations and may easily tilt towards hypocoagulability and bleeding. Acute kidney injury, bacterial infections and sepsis, and progression from acute decompensation to acute-on-chronic liver failure are associated with additional alterations of specific haemostatic pathways and a higher risk of bleeding. Unfortunately, there is no single laboratory method that can accurately stratify an individual patient's bleeding risk and guide pre-procedural prophylaxis. A better understanding of haemostatic alterations during acute illness would lead to more rational and individualised management of hospitalised patients with decompensated cirrhosis. This review will outline the latest findings on haemostatic alterations driven by acute kidney injury, bacterial infections/sepsis, and acute-on-chronic liver failure in these difficult-to-treat patients and provide evidence supporting more tailored management of bleeding risk.

Rational hemostatic management in cirrhosis: from old paradigms to new clinical challenges

INTRODUCTION

Patients with cirrhosis are at risk of both thrombotic and hemorrhagic events. Traditional hemostatic tests are inadequate to assess the complex and fragile balance of hemostasis in this setting, especially in advanced stages of disease such as decompensated cirrhosis or acute on chronic liver failure (ACLF). Furthermore, the indiscriminate use of pro-hemostatic agents for prophylaxis and treatment of bleeding episodes is still debated and often contraindicated. Alongside, splanchnic, and peripheral thrombotic events are frequent in this population and require management that involves a careful balance between risks and benefits of antithrombotic therapy.

AREAS COVERED

This review aims to address the state of the art on the clinical management of the hemostatic balance of cirrhosis in terms of established knowledge and future challenges.

EXPERT OPINION

The old paradigm of cirrhosis as a naturally anticoagulated condition has been challenged by more sophisticated global tests of hemostasis. Integrating this information in the clinical decision-making is still challenging for physicians and experts in hemostasis.

Thromboprophylaxis for venous thromboembolism prevention in hospitalized patients with cirrhosis: Guidance from the SSC of the ISTH

Hospital-associated venous thromboembolism (HA-VTE) is a major cause of morbidity and mortality and is internationally recognized as a significant patient safety issue. While cirrhosis was traditionally considered to predispose to bleeding, these patients are also at an increased risk of VTE, with an associated increase in mortality. Hospitalization rates of patients with cirrhosis are increasing, and decisions regarding thromboprophylaxis are complex due to the uncertain balance between thrombosis and bleeding risk. This is further accentuated by derangements of hemostasis in patients with cirrhosis that are often considered contraindications to pharmacological thromboprophylaxis. Due to the strict inclusion and exclusion criteria of seminal studies of VTE risk assessment and thromboprophylaxis, there is limited data to guide decision making in this patient group. This guidance document reviews the incidence and risk factors for HA-VTE in patients with cirrhosis, outlines evidence to inform the use of thromboprophylaxis, and provides pragmatic recommendations on VTE prevention for hospitalized patients with cirrhosis. In brief, in hospitalized patients with cirrhosis: We suggest inclusion of portal vein thrombosis as a distinct clinically important endpoint for future studies. We recommend against the use of thrombocytopenia and/or prolongation of prothrombin time/international normalized ratio as absolute contraindications to anticoagulant thromboprophylaxis. We suggest anticoagulant thromboprophylaxis in line with local protocols and suggest low molecular weight heparin (LMWH) or fondaparinux over unfractionated heparin (UFH). In renal impairment, we suggest LMWH over UFH. For critically ill patients, we suggest case-by-case consideration of thromboprophylaxis. We recommend research to refine VTE risk stratification, and to establish the optimal dosing and duration of thromboprophylaxis.

Increased platelet aggregation in patients with decompensated cirrhosis indicates higher risk of further decompensation and death

BACKGROUND & AIMS

Studies on platelet aggregation in cirrhosis are controversial because interpretation of platelet function is challenged by thrombocytopenia. We conducted a prospective study to investigate whole blood platelet aggregation in cirrhosis and its association with liver-related outcomes.

METHODS

Platelet aggregation was assessed by whole blood aggregometry (Multiplate®). To overcome the influence of platelet count and compare cirrhosis with thrombocytopenia vs. controls with normal platelet count, we calculated a ratio between platelet aggregation and platelet count (PLT ratio). Then, we prospectively followed patients with cirrhosis and ascertained predictors of decompensation, transplantation, and death.

RESULTS

Two-hundred and three patients with cirrhosis were prospectively recruited (77% decompensated). PLT ratio was significantly higher in cirrhosis than in those with chronic hepatitis and healthy individuals (0.44 vs. 0.25 and 0.26, respectively; p <0.0001). In cirrhosis, the ratio increased with disease severity (Child-Pugh class C>B>A) and was particularly elevated in decompensated patients with severe thrombocytopenia. Among decompensated patients, 65 had further decompensation, underwent transplantation, or died during a 6-month follow-up. On multivariate analysis, PLT ratio (odds ratio 1.87; 95% CI 1.23-2.84; p = 0.003) and MELD score (odds ratio 1.05; 95% CI 1.01-1.08; p = 0.01) were independently associated with outcome. The relative risk of events was 7.5-fold higher in patients with PLT ratio >0.75 vs. patients with PLT ratio <0.25 (95% CI 2.5-21.9; p = 0.003). The increased PLT ratio, its discriminative ability for composite outcome, and the prognostic value of PLT ratio >0.75 were confirmed in an independent cohort of hospitalized patients with decompensated cirrhosis (n = 41).

CONCLUSIONS

Patients with cirrhosis, particularly when decompensated, exhibit significantly increased whole blood platelet aggregation. Decompensated patients with a PLT ratio >0.75 have a >80% probability of further decompensation, transplantation, or liver-related death within 6 months.

LAY SUMMARY

In patients with cirrhosis, previous studies have suggested that platelets (i.e. circulating blood cells that help form clots to stop bleeding) are dysfunctional. In particular, these studies suggested that platelet aggregation (the process by which platelets adhere to each other to form clots) is reduced. Since platelet aggregation is important for clot formation, it has been hypothesized that alterations of platelet aggregation may be responsible for the increased risk of bleeding observed in patients with cirrhosis. Our study demonstrates: i) that platelet aggregation in patients with cirrhosis is higher than in healthy individuals; ii) that platelet aggregation in patients with decompensated cirrhosis (i.e. those who have already experienced some complications of cirrhosis) is particularly elevated and associated with risk of further complications and death.

Global hemostatic profiling in patients with decompensated cirrhosis and bacterial infections

Background & Aims

Bacterial infections in cirrhosis are associated with increased bleeding risk. To assess the factors responsible for bleeding tendency in patients with bacterial infections, we conducted a prospective study comparing all 3 aspects of hemostasis (platelets, coagulation, and fibrinolysis) in hospitalized patients with decompensated cirrhosis with vs. without bacterial infections.

Methods

Primary hemostasis assessment included whole blood platelet aggregation and von Willebrand factor (VWF). Coagulation assessment included procoagulant factors (fibrinogen, factor II, V, VII, VIII, IX, X, XI, XII, XIII), natural anticoagulants (protein C, protein S, antithrombin) and thrombomodulin-modified thrombin generation test. Fibrinolysis assessment included fibrinolytic factors (plasminogen, t-PA, PAI-1, α2-AP, TAFIa/ai) and plasmin-antiplasmin complex (PAP).

Results

Eighty patients with decompensated cirrhosis were included (40 with and 40 without bacterial infections). Severity of cirrhosis and platelet count were comparable between groups. At baseline, patients with cirrhosis and bacterial infections had significantly lower whole blood platelet aggregation, without significant differences in VWF. Regarding coagulation, bacterial infections were associated with reduced procoagulant factors VII and XII, and a significant reduction of all natural anticoagulants. However, thrombomodulin-modified thrombin generation was comparable between the study groups. Finally, although mixed potentially hypo-fibrinolytic (lower plasminogen) and hyper-fibrinolytic (higher t-PA) changes were present in bacterial infections, a comparable level of PAP was detected in both groups. Upon resolution of infection (n = 29/40), platelet aggregation further deteriorated whereas coagulation and fibrinolysis factors returned to levels observed in patients without bacterial infections.

Conclusion

In hospitalized patients with decompensated cirrhosis, bacterial infections are associated with reduced whole blood platelet aggregation and a significant decrease of all natural anticoagulants, which may unbalance hemostasis and potentially increase the risk of both bleeding and thrombosis.

Lay summary

Bacterial infections are a common issue in hospitalized patients with decompensated cirrhosis (i.e. patients hospitalized due to severe complications of advanced chronic liver disease). Patients with decompensated cirrhosis who acquire infections may be at increased risk of bleeding complications following invasive procedures (that is a procedure in which the body is penetrated or entered, for instance by a needle or a tube). As bleeding complications in decompensated cirrhosis are associated with a high risk of further decompensation and death, there is an urgent need to understand the factors responsible for such increased bleeding tendency. Herein, we investigated the alterations of hemostasis (that is the physiological process responsible for clot formation and stability) in patients with decompensated cirrhosis and bacterial infections. We found that development of bacterial infections in these patients is associated with alterations of hemostasis (particularly of platelets and clotting cascade) that may increase the risk of both bleeding and thrombotic complications.

Haemostatic alterations in patients with cirrhosis and hepatocellular carcinoma: laboratory evidence and clinical implications

Venous thrombosis is a frequent complication in cancer and is associated with high morbidity and mortality. Hepatocellular carcinoma (HCC) is the most common primary liver cancer and a leading cause of cancer-related death worldwide, and it is associated with preexisting cirrhosis in 90% of cases. Patients with cirrhosis acquire complex alterations in their haemostatic system that may predispose them to bleed or thrombotic complications. There is growing evidence that HCC may tilt the haemostatic equilibrium in cirrhosis towards hypercoagulability, thus increasing the risk of venous thrombosis. Previously described mechanisms of HCC-driven thrombophilia include thrombocytosis and increased platelet activation/function, increased fibrinogen concentration/polymerization, enhanced thrombin generation, hypofibrinolysis, and release of tissue factor-expressing microvesicles. Nevertheless, there are currently no specific guidelines on risk stratification and management of thromboprophylaxis in patients with cirrhosis and HCC. Our review endeavours to summarize the latest findings on epidemiology, risk factors and pathogenesis of non-malignant venous thrombosis in patients with cirrhosis and HCC, and provide evidence in support of tailored management of thrombotic risk in these patients.

Haemostatic alterations and management of haemostasis in patients with cirrhosis

Patients with cirrhosis frequently acquire complex changes in their haemostatic system including a decreased platelet count and decreased levels of various haemostatic proteins. Although historically patients with cirrhosis were thought to have a haemostasis-related bleeding tendency, it is now widely accepted that the haemostatic system of patients with cirrhosis remains in balance as a result of simultaneous changes in pro- and anti-haemostatic systems. The concept of rebalanced haemostasis has led to changes in clinical management, although firm evidence from well-designed clinical studies is largely lacking. For example, many invasive procedures in patients with cirrhosis and a prolonged prothrombin time are now performed without prophylaxis with fresh frozen plasma. Conversely, clinicians have become more aware of the need for anti-thrombotic therapy, even in those patients with abnormal routine coagulation tests. This paper will outline recent advances in pathogenesis, prevention and treatment of both bleeding and thrombotic complications in patients with cirrhosis. Among other topics, we will discuss the haemostatic status of acutely ill patients with cirrhosis, the various causes of bleeding in patients with cirrhosis, and how best to prevent or treat bleeding. In addition, we will discuss the hypercoagulable features of patients with cirrhosis, new insights into the pathogenesis of portal vein thrombosis, and how best to prevent or treat thromboses.

EASL Clinical Practice Guidelines on prevention and management of bleeding and thrombosis in patients with cirrhosis

The prevention and management of bleeding and thrombosis in patients with cirrhosis poses several difficult clinical questions. These Clinical Practice Guidelines have been developed to provide practical guidance on debated topics, including current views on haemostasis in liver disease, controversy regarding the need to correct thrombocytopenia and abnormalities in the coagulation system in patients undergoing invasive procedures, and the need for thromboprophylaxis in hospitalised patients with haemostatic abnormalities. Multiple recommendations in this document are based on interventions that the panel feels are not useful, even though widely applied in clinical practice.

Pathophysiology and management of bleeding and thrombosis in patients with liver disease

Patients with liver disease often develop complex changes in their haemostatic system. Frequently observed changes include thrombocytopaenia and altered plasma levels of most of the proteins involved in haemostasis. Although liver disease was historically classified as a haemostasis‐related bleeding disorder, it has now been well established that the antihaemostatic changes that promote bleeding are compensated for by prohaemostatic changes. Conventional coagulation tests however do not accurately reflect these prohaemostatic changes, resulting in an underestimation of haemostatic potential. Novel coagulation tests, such as viscoelastic tests (VETs) and thrombin generation assays (TGAs) better reflect the net result of the haemostatic changes in patients with liver disease, and demonstrate a new, “rebalanced” haemostatic status. Although rebalanced, this haemostatic status is more fragile than in patients without liver disease. Patients with liver disease are therefore not only at risk of bleeding but also at risk of thrombosis. Notably, however, many haemostatic complications in liver disease are not related to the haemostatic failure. It is, therefore, crucial to identify the cause of the bleed or thrombotic complication in order to provide adequate treatment. In this paper, we will elaborate on the haemostatic changes that occur in liver disease, reflect on laboratory and clinical studies over the last few years, and explore the pathophysiologies of bleeding and thrombosis in this specific patient group.

Recent Advances in the Management of Acute Variceal Hemorrhage

Gastrointestinal bleeding is one of the most relevant causes of death in patients with cirrhosis and clinically significant portal hypertension, with gastroesophageal varices being the most frequent source of hemorrhage. Despite survival has improved thanks to the standardization on medical treatment aiming to decrease portal hypertension and prevent infections, mortality remains significant. In this review, our goal is to discuss the most recent advances in the management of esophageal variceal hemorrhage in cirrhosis with specific attention to the treatment algorithms involving the use of indirect measurement of portal pressure (HVPG) and transjugular intrahepatic portosystemic shunt (TIPS), which aim to further reduce mortality in high-risk patients after acute variceal hemorrhage and in the setting of secondary prophylaxis.