Safety and efficacy of pharmacological thromboprophylaxis for hospitalized patients with cirrhosis: a single-center retrospective cohort study

Portal Vein Thrombosis: State-of-the-Art Review

Background: Portal vein thrombosis (PVT) is a rare disease with an estimated incidence of 2 to 4 cases per 100,000 inhabitants. The most common predisposing conditions for PVT are chronic liver diseases (cirrhosis), primary or secondary hepatobiliary malignancy, major infectious or inflammatory abdominal disease, or myeloproliferative disorders. Methods: PVT can be classified on the basis of the anatomical site, the degree of venous occlusion, and the timing and type of presentation. The main differential diagnosis of PVT, both acute and chronic, is malignant portal vein invasion, most frequently by hepatocarcinoma, or constriction (typically by pancreatic cancer or cholangiocarcinoma). Results: The management of PVT is based on anticoagulation and the treatment of predisposing conditions. The aim of anticoagulation in acute thrombosis is to prevent the extension of the clot and enable the recanalization of the vein to avoid the development of complications, such as intestinal infarction and portal hypertension. Conclusions: The treatment with anticoagulant therapy favors the reduction of portal hypertension, and this allows for a decrease in the risk of bleeding, especially in patients with esophageal varices. The anticoagulant treatment is generally recommended for at least three to six months. Prosecution of anticoagulation is advised until recanalization or lifelong if the patient has an underlying permanent pro-coagulant condition that cannot be corrected or if there is thrombosis extending to the mesenteric veins.

Trauma Patients With Cirrhosis Have a Similar Risk of Unplanned Operation and Decreased Associated Risk of Mortality With Venous Thromboembolism Chemoprophylaxis

INTRODUCTION

Patients with cirrhosis have an increased risk of complications after trauma, including bleeding, unplanned operations, and death. The benefit of venous thromboembolism (VTE) chemoprophylaxis in trauma patients with cirrhosis (CTPs) is not clear, especially since cirrhotic patients are hypercoagulable. We hypothesized that CTPs receiving VTE chemoprophylaxis (vCP) have a lower risk of death with no increased risk for unplanned operations compared to patients with cirrhosis not receiving vCP.

METHODS

The 2017-2019 TQIP database was queried for patients with cirrhosis. Patients on outpatient anticoagulant therapy or with a history of bleeding diathesis, interhospital transfers, severe head injury, deaths < 72 hours, and hospitalization < 2 days were excluded. A multivariable logistic regression analysis was performed.

RESULTS

From 10,011 CTPs, 6,350 (63.4%) received vCP. Compared to patients without vCP, the vCP group had decreased mortality (4.5% vs. 5.5%, P = 0.03) but a similar rate of unplanned operations (1% vs. 0.6%, P = 0.07). This persisted on multivariable analysis, with a decreased associated risk of mortality (OR 0.54, CI 0.42-0.69, P < 0.001), and a similar risk of unplanned operation (P = 0.85).

CONCLUSION

CTPs received VTE chemoprophylaxis in under two-thirds of cases. On multivariable analysis, vCP was associated with a decreased risk of mortality and a similar risk of unplanned operations. These findings suggest that vCP appears safe. Further investigation is needed to confirm this finding.

Bleeding and Thrombotic Complications in Patients With Cirrhosis: A State-of-the-Art Appraisal

Much has evolved over the past 25 years regarding our understanding of the coagulopathy of liver disease. Paradoxically, this form of coagulopathy is relatively hypercoagulability despite the common clinical impression of a hemorrhagic tendency. The latter is largely driven by portal-mesenteric venous pressure (ie, portal hypertension) and has little to do with hemostatic pathways. It cannot be emphasized enough that the INR does not offer a meaningful measure in this situation and may lead to interventions such as fresh frozen plasma that can actually worsen portal pressure and hence pressure-driven bleeding. With regard to procedure-related bleeding, we point out substantial differences in the definition of high-risk procedures and propose a new operational definition dependent on the applicability of local hemostatic measures, although this requires further investigation. The common occurrence of venous thrombosis in these patients requires careful consideration of hemostatic pathways and overall risk and benefit of intervention. The decision regarding anticoagulation therapy needs to be driven not only by a global assessment including history of non-portal hypertensive-related bleeding, but also by fall risk which can result in head trauma in patients prone to encephalopathy. This is probably best estimated by frailty but has yet to be adequately investigated. In the background of these concerns, several superimposed and complex conditions including infections and renal dysfunction should be taken into account. Inherited forms of thrombophilia in the setting of cirrhosis perhaps do not outweigh the thrombophilia inherent to liver disease but warrant further consideration.

Outcome of pharmacological thromboprophylaxis in hospitalized patients with cirrhosis - a systematic review and meta-analysis

BACKGROUND

Portal hypertension in cirrhosis brings about a complex interplay in the risks of bleeding and thrombosis. It is unclear whether hospitalized patients with cirrhosis need pharmacological prophylaxis for venous thromboembolism (VTE), as it may increase the risk of bleeding. We aimed to compare the outcome of hospitalized patients with cirrhosis with and without pharmacological thromboprophylaxis.

METHODS

A comprehensive search of three databases was conducted from inception to August 2022 for studies comparing the outcome of hospitalized patients with cirrhosis with and without pharmacological prophylaxis for VTE. Odds ratios (OR) with 95% confidence intervals (CIs) were calculated for the outcomes of VTE or bleeding.

RESULTS

Overall, 12 studies were included in the final analysis. The pooled incidence of VTE in patients with and without thromboprophylaxis was 1.9% (95% CI: 0.8-2.9) and 1.9% (95% CI: 0.9-2.9), respectively. The odds of VTE were comparable between the groups with OR 1.11 (95% CI: 0.76-1.62). The pooled incidence of bleeding events in patients with and without thromboprophylaxis was 6.7% (95% CI: 3.6-9.8) and 10.4% (95% CI: 6.6-14.1), respectively. There was no significant difference in the odds of overall bleeding (OR 0.68; 95% CI: 0.30-1.52) or major bleeding (OR 1.18; 95% CI: 0.55-2.56) between the groups. There was no significant difference in the relative effects on sensitivity analysis.

CONCLUSION

The present analysis could not demonstrate the benefit of pharmacological thromboprophylaxis in reducing in-hospital VTE in patients with cirrhosis. Future studies are required to assess the role of risk prediction models in hospitalized patients with cirrhosis.

Red blood cell transfusion is associated with an increased risk of splanchnic vein thrombosis in patients with cirrhosis

BACKGROUND

Haemorrhage and coagulation disorders are common complications in cirrhotic patients, which cause blood products transfusion, and mounting evidence suggested that red blood cells (RBCs) were associated with pathologic thrombosis and RBC transfusion increased the risk of venous thromboembolism (VTE).

AIMS

The aim of the study was to investigate the association of RBC transfusion with splanchnic vein thrombosis (SVT) in cirrhotic patients.

MATERIALS & METHODS

We retrospectively reviewed patients with cirrhosis admitted in the Hunan Provincial People's Hospital between January 2010 and September 2020. Demographic data, the development of SVT, blood transfusion product type and RBC transfusion dose were collected. Multivariate logistic regression analyses and propensity matching analysis (PSM) were performed to identify the association between RBC transfusion and development of SVT.

RESULTS

A total of 4479 patients with cirrhosis were enrolled in the study. SVT occurred in 48 (12.4%) cirrhotic patients in RBC transfusion group, and 233 (5.7%) cirrhotic patients in non-RBC transfusion group. RBC transfusion was significantly associated with an increased risk of SVT (unadjusted odds ratio [OR] 2.345, 95% confidence interval [CI] 1.686-3.262, p < 0.001). Notably, this association remained robust after PSM, and the volume of RBC transfusion was associated with SVT in a dose-dependent manner.

CONCLUSION

This study suggested that RBC transfusion was associated with an increased risk of SVT in cirrhotic patients. High quality clinical study will be needed to further validate the association between RBC transfusion and SVT.

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.

Mastering Core Recommendations during HEPAtology ROUNDS in Patients with Advanced Chronic Liver Disease

Efficient and thorough care of hospitalized patients with advanced chronic liver disease is of utter importance to improve outcomes and optimize quality of life. This requires understanding current evidence and best practices. To facilitate focus on up-to-date knowledge and a practical approach, we have created the HEPA-ROUNDS mnemonic while outlining a practical review of the literature with critical appraisal for the busy clinician. The HEPA-ROUNDS mnemonic provides a structured approach that incorporates critical concepts in terms of prevention, management, and prognostication of the most common complications frequently encountered in patients with advanced chronic liver disease. In addition, implementing the HEPA-ROUNDS mnemonic can facilitate education for trainees and staff caring for patients with advanced chronic liver disease.

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.

Heparins for prevention and treatment of venous thromboembolism in cirrhosis: Research advances

Current evidence suggests that liver cirrhosis may increase the risk of venous thromboembolism (VTE). In cirrhosis, common types of VTE include portal vein thrombosis (PVT), deep vein thrombosis, and pulmonary embolism (PE). Heparins are the most commonly prescribed anticoagulants for the prevention and treatment of VTE. However, the indications, choice, dosage, and monitoring of heparins in cirrhosis remain inconclusive. This paper aims to review the advances in the research of heparins for the prevention and treatment of VTE in cirrhosis to optimize the treatment strategy.

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.

Coagulopathies in Intensive Care Medicine: Balancing Act between Thrombosis and Bleeding

Patient Blood Management advocates an individualized treatment approach, tailored to each patient's needs, in order to reduce unnecessary exposure to allogeneic blood products. The optimization of hemostasis and minimization of blood loss is of high importance when it comes to critical care patients, as coagulopathies are a common phenomenon among them and may significantly impact morbidity and mortality. Treating coagulopathies is complex as thrombotic and hemorrhagic conditions may coexist and the medications at hand to modulate hemostasis can be powerful. The cornerstones of coagulation management are an appropriate patient evaluation, including the individual risk of bleeding weighed against the risk of thrombosis, a proper diagnostic work-up of the coagulopathy's etiology, treatment with targeted therapies, and transfusion of blood product components when clinically indicated in a goal-directed manner. In this article, we will outline various reasons for coagulopathy in critical care patients to highlight the aspects that need special consideration. The treatment options outlined in this article include anticoagulation, anticoagulant reversal, clotting factor concentrates, antifibrinolytic agents, desmopressin, fresh frozen plasma, and platelets. This article outlines concepts with the aim of the minimization of complications associated with coagulopathies in critically ill patients. Hereditary coagulopathies will be omitted in this review.

When and how to use direct oral anticoagulants in patients with advanced chronic liver disease?

Direct oral anticoagulants (DOACs) emerged as effective and safe alternatives to traditional anticoagulants for the prevention and treatment of venous thromboembolic disease and the prevention of stroke in non-valvular atrial fibrillation. Patients with advanced chronic liver disease (ACLD) have a higher risk of thromboembolism and bleeding than patients with normal liver function. Therefore, anticoagulation and, in particular, direct oral anticoagulants play a central role. Portal vein thrombosis is a relatively frequent complication in patients with ACLD, but its treatment remains challenging. DOACs have been introduced in clinical practice and demonstrated similar efficacy and safety profiles compared with vitamin K antagonist and heparins. However, further data about the use of DOACs in patients suffering from ACLD are needed. This review summarizes current knowledge in terms of anticoagulation in patients with ACLD and focuses on the available data about the use of DOACs in this population.

The hemostatic and thrombotic complications of liver disease

Hepatic cirrhosis leads to numerous hematologic derangements resulting in a complex and tenuously rebalanced hemostatic milieu. The utility of common hematologic tests including the INR and aPTT in assessing hemostatic and thrombotic risk in patients with cirrhosis is limited, and consensus on transfusion thresholds and proper management of thrombotic complications continues to evolve. This review summarizes the pathophysiology of key derangements of hemostasis including those of platelets, von Willebrand factor, pro- and anticoagulation factors, and fibrin. Additionally, the pathogenesis, consequences, optimal management, and prevention of major thrombotic and bleeding complications in cirrhosis arte discussed.

Heparins have adequate ex vivo anticoagulant effects in hospitalized patients with cirrhosis

BACKGROUND

Patients with cirrhosis are at risk of venous thromboembolism (VTE), but strategies for thromboprophylaxis have not been defined. Previous in vitro studies suggest an altered anticoagulant effect of heparins in patients with cirrhosis.

OBJECTIVES

To assess the anticoagulant effects of prophylactic low-molecular-weight heparin (LMWH) or unfractionated heparin (UFH) doses in patients with cirrhosis in a real-life clinical setting.

METHODS

We studied patients with cirrhosis (n = 16) and acute-on-chronic liver failure (ACLF) (n = 14), and compared these with patients without underlying liver disease admitted to non-liver general medical wards (n = 18) and non-liver intensive care units (n = 14), respectively. Blood samples were taken before and 4 h after administration of the first dose of LMWH or UFH. We assessed hemostatic status using thrombin generation assays, thrombin-antithrombin complexes (TAT), and conventional coagulation assays, and included healthy controls (n = 20) to establish reference values. Anti-Xa activity was determined to estimate peak heparin levels.

RESULTS

Baseline thrombin generation was similar among all cohorts and healthy controls despite alterations in conventional coagulation assays. On heparin, both absolute and proportional changes of thrombin generation were comparable between all four cohorts (-62% to -85%). TAT levels decreased in all cohorts apart from the ACLF cohort, but did not correlate with the proportional change in thrombin generation. Anti-Xa activity correlated with the proportional change in thrombin generation in patients receiving LMWH, but not in patients receiving UFH.

CONCLUSIONS

These data suggest that current prophylactic heparin doses have comparable anticoagulant effects in patients with cirrhosis compared with patients without underlying liver disease.

The Spectrum of Disease Severity in Cirrhosis and Its Implications for Hemostasis

Bleeding and thrombosis are both common complications that patients with advanced liver disease experience. While hemostatic pathways remain largely intact with cirrhosis, this balance can quickly shift in the direction of bleeding or clotting in an unpredictable manner. A growing body of literature is attempting to shed light on difficult scenarios that clinicians often face, ranging from predicting and mitigating bleeding risk in those who need invasive procedures to determining the best strategies to manage both bleeding and thrombotic complications when they occur. Studies examining hemostasis in those with advanced liver disease, however, often include heterogeneous cohorts with varied methodology. While these studies often select a cohort of all types and degrees of cirrhosis, emerging evidence suggests significant differences in underlying systemic inflammation and hemostatic abnormalities among specific phenotypes of liver disease, ranging from compensated cirrhosis to decompensated cirrhosis and acute-on-chronic liver failure. It is paramount that future studies account for these differing disease severities if we hope to address the many critical knowledge gaps in this field.

Overuse of venous thromboembolism prophylaxis among hospitalized patients with liver disease

INTRODUCTION

Patients with liver disease are at risk of venous thromboembolism (VTE); however, little is understood regarding the safety and efficacy of VTE prophylaxis in patients with cirrhosis. We examined the application of a VTE risk assessment model in VTE prophylaxis decision-making in a closed cohort of hospitalized patients with liver disease.

METHODS

Sequential patients admitted to an inpatient hepatology service at a tertiary care center were evaluated for need for VTE prophylaxis. Risk assessment by IMPROVE was compared with current practice patterns of VTE prophylaxis. Rates of bleeding and clotting events were noted.

RESULTS

98 patient encounters were included in our analysis. 76% of patients received VTE prophylaxis in practice. IMPROVE recommended use of VTE prophylaxis in 19% of patients. Patients who received VTE prophylaxis that was not warranted had significantly lower risk of clotting compared with patients in whom VTE prophylaxis was warranted per IMPROVE.

CONCLUSIONS

Application of IMPROVE risk assessment would significantly reduce VTE prophylaxis use among hospitalized patients with liver disease. Our findings challenge the "one-size-fits-all" current practice pattern of VTE prophylaxis. Future studies are needed in large cohorts of hospitalized patients with liver disease that include clinical outcomes of bleeding and clotting risk.

Bleeding Risk of Therapeutic Unfractionated Heparin and Low Molecular Weight Heparin in Patients with Cirrhosis

BACKGROUND AND OBJECTIVE

Patients with cirrhosis are simultaneously at an increased risk of bleeding and thrombosis. Studies comparing the safety of parenteral anticoagulants in this population are lacking. This study evaluated the safety of therapeutic unfractionated heparin versus low molecular weight heparin in patients with cirrhosis.

METHODS

This system-wide, retrospective cohort study included adults with cirrhosis receiving unfractionated heparin or low molecular weight heparin for the treatment of acute venous thromboembolism. The primary endpoint was the incidence of major bleeding.

RESULTS

Eighty-two patients were included in this study, with 52 receiving unfractionated heparin and 30 receiving low molecular weight heparin. More major bleeding occurred in the unfractionated heparin arm compared to the low molecular weight heparin arm (19.2% vs 0%, p = 0.010).

CONCLUSIONS

Low molecular weight heparin may be a safer option in patients with cirrhosis treated for acute venous thromboembolism, but future studies should confirm these findings.

Transfusion strategies in patients with cirrhosis

Bleeding related to portal hypertension and coagulopathy is a common complication in patients with cirrhosis. Complications and management of bleeding is a significant source of healthcare cost and utilization, as well as morbidity and mortality. Due to the scarcity of evidence surrounding transfusion strategies and hemostatic interventions in patients with cirrhosis, there has been significant debate regarding the best practice. Emerging data suggest that evidence supporting transfusion of packed red blood cells to a hemoglobin threshold of 7-8 g/dL is strong. thrombopoietin (TPO) receptor agonists have shown promise in increasing platelet levels and reducing transfusions preprocedurally, although have not specifically been found to reduce bleeding risk. Data for viscoelastic testing (VET)-guided transfusions appear favorable for reducing blood transfusion requirements prior to minor procedures and during orthotopic liver transplantation. Hemostatic agents such as recombinant factor VIIa, prothrombin complex concentrates, and tranexamic acid have been examined but their role in cirrhotic patients is unclear. Other areas of growing interest include balanced ratio and whole blood transfusion. In the following manuscript, we summarize the most up to date evidence for threshold-guided, VET-guided, balanced-ratio, and whole blood transfusions as well as the use of hemostatic agents in cirrhotic patients to provide practice guidance to clinicians.

Effectiveness of venous thromboembolism prophylaxis in patients with liver disease

BACKGROUND

Patients with liver disease are concomitantly at increased risk of venous thromboembolism (VTE) and bleeding events due to changes in the balance of pro- and anti-hemostatic substances. As such, recommendations for the use of pharmacological VTE prophylaxis are lacking. Recent studies have found no difference in rates of VTE in those receiving and not receiving pharmacological VTE prophylaxis, though most studies have been small. Thus, our study sought to establish if pharmacological VTE prophylaxis is effective and safe in patients with liver disease.

AIM

To determine if there is net clinical benefit to providing pharmacological VTE prophylaxis to cirrhotic patients.

METHODS

In this retrospective study, 1806 patients were propensity matched to assess if pharmacological VTE prophylaxis is effective and safe in patients with cirrhosis. Patients were divided and evaluated based on receipt of pharmacological VTE prophylaxis.

RESULTS

The composite primary outcome of VTE or major bleeding was more common in the no prophylaxis group than the prophylaxis group (8.7% vs 5.1%, P = 0.002), though this outcome was driven by higher rates of major bleeding (6.9% vs 2.9%, P < 0.001) rather than VTE (1.9% vs 2.2%, P = 0.62). There was no difference in length of stay or in-hospital mortality between groups. Pharmacological VTE prophylaxis was independently associated with lower rates of major bleeding (OR = 0.42, 95%CI: 0.25-0.68, P = 0.0005), but was not protective against VTE on multivariable analysis.

CONCLUSION

Pharmacological VTE prophylaxis was not associated with a significant reduction in the rate of VTE in patients with liver disease, though no increase in major bleeding events was observed.

Assessment of bleeding in chronic liver disease and coagulopathy using the IMPROVE bleeding criteria

BACKGROUND

In this study, the authors utilized the IMPROVE (International Medical Prevention Registry on Venous Thromboembolism) bleeding definition to explore the safety profile of pharmacologic venous thromboembolism (VTE) prophylaxis in patients with chronic liver disease (CLD) and concurrent coagulopathy (INR ≥1.5).

METHODS

A retrospective study was conducted on 193 adult patient admissions with a diagnosis of CLD and INR ≥1.5 not due to therapeutic anticoagulation. Patients were stratified based on their receipt of pharmacological thromboprophylaxis or not during hospitalization. The rates of overall bleeding, defined as the composite of major bleeding and clinically relevant non-major bleeding; major bleeding; and clinically relevant non-major bleeding, within 14 days of admission were evaluated. Secondary endpoints included the rates of thrombosis and mortality.

RESULTS

The composite of overall bleeding occurred in 17.6% of the admissions. More patients in the group not receiving pharmacological thromboprophylaxis had overall bleeding (18.5% vs 10%), major bleeding (13.3% vs 10%), and clinically relevant non-major bleeding (14.5% vs 5%), with overlapping 95% CI. When stratified per pharmacological thromboprophylaxis status, IMPROVE bleeding risk score (BRS) ≥ 7 was associated with higher rates of overall bleeding, major bleeding, and clinically relevant non-major bleeding as compared to IMPROVE BRS <7, whether patients received or did not receive pharmacological thromboprophylaxis. The overall incidence of in-hospital mortality among our study population was 15.5%. Receiving pharmacological thromboprophylaxis was markedly associated with higher in-hospital mortality (OR = 16.58, 95% CI = 4.47-61.45).

CONCLUSION

This study shows that the IMPROVE BRS calculated on admission may serve as a guide for omission of thromboprophylaxis in advanced CLD.

Cancer-Associated Thrombosis in Cirrhotic Patients with Hepatocellular Carcinoma

It is common knowledge that cancer patients are more prone to develop venous thromboembolic complications (VTE). It is therefore not surprising that patients with hepatocellular carcinoma (HCC) present with a significant risk of VTE, with the portal vein being the most frequent site (PVT). However, patients with HCC are peculiar as both cancer and liver cirrhosis are conditions that can perturb the hemostatic balance towards a prothrombotic state. Because HCC-related hypercoagulability is not clarified at all, the aim of the present review is to summarize the currently available knowledge on epidemiology and pathogenesis of non-malignant thrombotic complications in patients with liver cirrhosis and HCC. They are at increased risk to develop both PVT and non-splanchnic VTE, indicating that both local and systemic factors can foster the development of site-specific thrombosis. Recent studies have suggested multiple and often interrelated mechanisms through which HCC can tip the hemostatic balance of liver cirrhosis towards hypercoagulability. Described mechanisms include increased fibrinogen concentration/polymerization, thrombocytosis, and release of tissue factor-expressing extracellular vesicles. Currently, there are no specific guidelines on the use of thromboprophylaxis in this unique population. There is the urgent need of prospective studies assessing which patients have the highest prothrombotic profile and would therefore benefit from early thromboprophylaxis.

Venous thrombosis in unusual sites: A practical review for the hematologist

Thrombosis of unusual venous sites encompasses a large part of consultative hematology and is encountered routinely by practicing hematologists. Contrary to the more commonly encountered lower extremity venous thrombosis and common cardiovascular disorders, the various thromboses outlined in this review have unique presentations, pathophysiology, workup, and treatments that all hematologists should be aware of. This review attempts to outline the most up to date literature on cerebral, retinal, upper extremity, hepatic, portal, splenic, mesenteric, and renal vein thrombosis, focusing on the incidence, pathophysiology, provoking factors, and current recommended treatments for each type of unusual thrombosis to provide a useful and practical review for the hematologist.

Hypercoagulability in End-stage Liver Disease: Review of Epidemiology, Etiology, and Management

In this review, we analyze the epidemiology of thromboses related to end-stage liver disease (ESLD), discuss causes of hypercoagulability, describe susceptible populations, and critically evaluate proposed prophylaxis and treatment of thromboses. Classically, ESLD has been regarded as a model for coagulopathy, and patients were deemed to be at high risk for bleeding complications. Patients with ESLD are not auto-anticoagulated, and they do not have a lower risk of portal vein thrombosis, intracardiac thrombus formation, pulmonary embolism or hepatic artery thrombosis. Though the cause of hypercoagulability is multifactorial, endothelial dysfunction likely plays a central role for all patients with ESLD. Some subpopulations, such as patients with nonalcoholic steatohepatitis and autoimmune conditions, are at increased risk of thrombotic events as are patients of Hispanic ethnicity. The science behind prophylaxis of different types of clotting and treatment of thromboses is developing rapidly. A number of medications, including low molecular weight heparin, unfractionated heparin, aspirin, vitamin K antagonists, and direct oral anticoagulants can be used, but clear guidelines are lacking. Acute intraoperative clotting can be associated with high mortality. Routine use of transesophageal echocardiography can be helpful in early recognition and treatment of intraoperative thrombosis. Heparin should be reserved for cases of intracardiac thrombus/pulmonary embolism without hemodynamic instability. In unstable patients, low dose of recombinant tissue plasminogen activator can be used. In this new era of heightened awareness of thrombotic events in ESLD patients, prospective randomized trials are urgently needed to best guide clinical practice.

Clinical effect of enoxaparin on international normalized ratio following hepato-pancreatico-biliary and gastroesophageal resection

BACKGROUND AND OBJECTIVES

Enoxaparin inactivates factor Xa via a complex formed after binding to circulating anti-thrombin III. This mechanism is reported not to alter hemostatic measures such as clotting time, PT, or PTT. To date, no clinical trials have shown a causal relationship between the clinical/pharmacological effects of enoxaparin on international normalized ratio (INR). The aim of our study is to show the clinical effect of enoxaparin on INR.

METHODS

Patients (N = 350) were reviewed from our prospective IRB approved databases undergoing gastroesophageal or hepatobiliary surgeries. INR levels were recorded for 6 days: pre-operative to 5 days after surgery.

RESULTS

Patients (N = 289) received enoxaparin daily starting post-operative day 1, while 61 patients who did not receive enoxaparin were used as controls. The mean post-operative INR in both the 30 and 40 mg groups were both significantly higher than the mean post-operative INR of the control group (P = 0.015 and P = 0.00075, respectively); however postoperative hemoglobin levels were not significantly lower in the enoxaparin versus control.

CONCLUSION

This is the first clinical evidence of the effect of enoxaparin on INR in patients undergoing abdominal surgeries for malignancies. We demonstrate an increase in the INR for patients who received enoxaparin for post-operative VTE prophylaxis.

Coagulopathy Before and After Liver Transplantation: From the Hepatic to the Systemic Circulatory Systems

The hemostatic environment in patients with cirrhosis is a delicate balance between prohemostatic and antihemostatic factors. There is a lack of effective laboratory measures of the hemostatic system in patients with cirrhosis. Many are predisposed to pulmonary embolus, deep vein thrombosis, and portal vein thrombosis in the pretransplantation setting. This pretransplantation hypercoagulable milieu seems to extend for at least several months post-transplantation. Patients with nonalcoholic fatty liver disease, inherited thrombophilia, portal hypertension in the absence of cirrhosis, and hepatocellular carcinoma often require individualized approach to anticoagulation. Early reports suggest a potential role for low-molecular-weight heparins and direct-acting anticoagulants.

Hemostasis, bleeding and thrombosis in liver disease

The presence of cirrhosis poses an increased risk of both thrombosis and bleeding in individuals with chronic liver disease. This duality is a result of a dynamic disequilibrium between procoagulant and anticoagulant states in individuals with cirrhosis. The mechanism of this imbalance in cirrhosis remains unclear. It is known that the progression of cirrhosis leads to decreased synthetic function and a concurrent lack of natural anticoagulants. Other proposed mechanisms contributing to this hemostatic imbalance include decreased platelet production, increased platelet destruction from hypersplenism, decreased synthesis of Vitamin K-dependent and independent clotting factors and anticoagulant factors, and alterations in purinergic signaling pathways.

Given the current state of flux in our understanding of bleeding and thrombophilia in cirrhosis, the recommendations for treatment of these conditions are still evolving.

We provide a current update on the proposed pathophysiology of altered hemostasis and thrombophilia in cirrhosis. We discuss recent studies in portal vein thrombosis (PVT) and venous thromboembolism (VTE), which are the common thrombotic consequences of cirrhosis, resulting in substantive morbidity and mortality. To address these, we discuss new prophylactic interventions and current treatment options to manage the heightened risk of thrombosis in cirrhosis, while limiting hemorrhagic complications.

The efficacy and safety of direct oral anticoagulants vs traditional anticoagulants in cirrhosis

INTRODUCTION

The coagulopathy of cirrhosis is complex, placing patients at risk for both bleeding and thrombosis. Direct oral anticoagulants (DOACs) have equivalent or superior efficacy and safety as compared to vitamin K antagonists (VKAs); however, their efficacy and safety in liver cirrhosis has not been studied. To better define this, we evaluated outcomes of patients with cirrhosis prescribed DOACs compared to other anticoagulants at our center.

METHODS

Retrospective cohort study of patients with cirrhosis prescribed therapeutic anticoagulation over a 3-year period for thrombosis or prevention of stroke in patients with atrial fibrillation. The primary outcomes of interest were bleeding events and recurrent thrombosis or stroke.

RESULTS

During the study period, 27 patients with cirrhosis were prescribed a DOAC and 18 were prescribed VKA or low molecular weight heparin (LMWH). Both groups had similar total bleeding events (8 DOAC vs 10 other, P=.12). There were significantly less major bleeding episodes in the DOAC group (1 [4%] vs 5 [28%], P=.03). Recurrent thrombosis occurred in one patient receiving a DOAC (4%) and one patient (6%) receiving other anticoagulation (P=1.0).

CONCLUSIONS

Direct oral anticoagulant use in patients with cirrhosis may be as safe as traditional anticoagulants. Patients with cirrhosis at our center prescribed DOACs had less major bleeding events, while maintaining efficacy at preventing stroke or thrombosis.

Direct Oral Anticoagulants in Cirrhosis

OPINION STATEMENT

The risk of thrombosis in patients with chronic liver disease is increasingly recognized. As patients with cirrhosis develop indications for anticoagulation therapy (e.g., venous thromboembolism, portal vein thrombosis, or atrial fibrillation), providers are left to make difficult decisions when selecting therapeutics with little evidence to rely on. Current practice supports the use of low molecular weight heparin or vitamin K antagonists in select patients with cirrhosis requiring anticoagulation. While traditional anticoagulants may be safe and effective in select patients with compensated cirrhosis, the use of direct oral anticoagulants (DOAC) is more controversial. DOAC are desirable as they do not require routine monitoring and can be taken orally. Unfortunately, patients with chronic liver disease were excluded from clinical trials that demonstrated efficacy and safety when compared to traditional anticoagulation. Data are now emerging that support the use of DOAC in well-compensated cirrhosis patients. However, further study is needed with all (traditional and DOAC) anticoagulation medications in patients with cirrhosis to better ensure safety and further understand pharmacologic properties in this challenging population.

Anticoagulation in Patients With Cirrhosis: Caught Between a Rock-Liver and a Hard Place

OBJECTIVE

To review current literature for anticoagulation in patients with cirrhosis and provide a summary of the effects of cirrhosis on the coagulation cascade, therapeutic monitoring through interpretation of antifactor Xa (anti-Xa), activated partial thromboplastin time (aPTT), and international normalized ratio (INR) as well as current prophylaxis and treatment recommendations in cirrhotic patients.

METHODS

A systematic electronic literature search was conducted in PubMed using the key termsanticoagulation, warfarin, low-molecular-weight heparin(LMWH),unfractionated heparin(UFH),target-specific oral anticoagulants, deep-vein thrombosis(DVT),pulmonary embolism(PE),portal vein thrombosis(PVT),venous thromboembolism, anti-Xa, activated partial thromboplastin time, anticoagulation therapeutic monitoring, coagulopathy, coagulation cascade, chronic liver disease, cirrhosis, anddecompensated liver disease

STUDY SELECTION

Studies written in the English language from January 2000 to December 2015 were considered for this review article. All search results were reviewed, and the relevance of each article was determined by authors independently.

CONCLUSIONS

Patients with cirrhosis are at higher risk for both bleeding and thrombosis-related complications. Cirrhosis affects production of both procoagulant and anticoagulant factors, thus resulting in increased INR and aPTT levels and decreased anti-Xa levels. LMWH is the treatment of choice for the prevention and treatment of DVT/PE/PVT in patients with cirrhosis, and monitoring with anti-Xa levels for dose adjustment is not recommended. UFH is an alternative in cirrhotic patients for shorter-term use and in cases of severe renal dysfunction and/or hemodynamic instability. Cirrhotic patients on anticoagulation therapy should be monitored closely for signs and symptoms of bleeding and thrombosis.