Whole blood thrombin generation profiles of patients with cirrhosis explored with a near patient assay

Cellular Components Contributing to the Development of Venous Thrombosis in Patients with Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive type of cancer and has a poor prognosis. Patients with PDAC are at high risk of developing thromboembolic events, which is a leading cause of morbidity and mortality following cancer progression. Plasma-derived coagulation is the most studied process in cancer-associated thrombosis. Other blood components, such as platelets, red blood cells, and white blood cells, have been gaining less attention. This narrative review addresses the literature on the role of cellular components in the development of venous thromboembolism (VTE) in patients with PDAC. Blood cells seem to play an important role in the development of VTE. Altered blood cell counts, i.e., leukocytosis, thrombocytosis, and anemia, have been found to associate with VTE risk. Tumor-related activation of leukocytes leads to the release of tissue factor-expressing microvesicles and the formation of neutrophil extracellular traps, initiating coagulation and forming a scaffold for thrombi. Tissue factor-expressing microvesicles are also thought to be released by PDAC cells. PDAC cells have been shown to stimulate platelet activation and aggregation, proposedly via the secretion of podoplanin and mucins. Hypofibrinolysis, partially explained by increased plasminogen activator inhibitor-1 activity, is observed in PDAC. In short, PDAC-associated hypercoagulability is a complex and multifactorial process. A better understanding of cellular contributions to hypercoagulability might lead to the improvement of diagnostic tests to identify PDAC patients at highest risk of VTE.

Altered whole blood thrombin generation and hyperresponsive platelets in patients with pancreatic cancer

BACKGROUND

Thromboembolic disease is a major complication in patients with pancreatic ductal adenocarcinoma (PDAC). Patients with PDAC often have altered blood cell counts, which are associated with venous thromboembolism (VTE) development. The high thrombotic risk in patients with PDAC may be partially caused by procoagulant blood cells.

OBJECTIVES

The aim of this study was to compare blood cell-dependent coagulation between patients with PDAC (n = 18) and healthy controls matched for age and sex (n = 18).

METHODS

Thrombin generation (TG) was measured in whole blood (WB) and plasma. The capacity of platelets to release granules (PGRCs) was measured in WB. We explored the occurrence of thromboembolic events in patients with PDAC during a 6-month follow-up.

RESULTS

Patients showed an increased endogenous thrombin potential in WB compared with controls. This difference was not observed in plasma, indicating a procoagulant effect of blood cells. Both in WB and plasma, the lag time was prolonged in patients compared with controls. Patients had hyperresponsive platelets, with a shorter time to peak granule release. Of the 18 patients with PDAC, 4 developed a venous thromboembolism (22%) and 1 developed an arterial thrombosis (6%). A shorter lag time in WB, but not in plasma, and an increased PGRC were associated with thromboembolic events.

CONCLUSION

Patients with PDAC have an increased and delayed WB TG coagulation profile compared with controls. A shorter lag time in WB TG and increased PGRC are associated with the incidence of thromboembolic events. Platelets appear to be key players in thrombosis development. Measuring hemostasis in WB could improve thrombosis risk estimation in patients with PDAC.

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.

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.

Crucial roles of red blood cells and platelets in whole blood thrombin generation

Red blood cells (RBCs) and platelets contribute to the coagulation capacity in bleeding and thrombotic disorders. The thrombin generation (TG) process is considered to reflect the interactions between plasma coagulation and the various blood cells. Using a new high-throughput method capturing the complete TG curve, we were able to compare TG in whole blood and autologous platelet-rich and platelet-poor plasma to redefine the blood cell contributions to the clotting process. We report a faster and initially higher generation of thrombin and shorter coagulation time in whole blood than in platelet-rich plasma upon low concentrations of coagulant triggers, including tissue factor, Russell viper venom factor X, factor Xa, factor XIa, and thrombin. The TG was accelerated with increased hematocrit and delayed after prior treatment of RBC with phosphatidylserine-blocking annexin A5. RBC treatment with ionomycin increased phosphatidylserine exposure, confirmed by flow cytometry, and increased the TG process. In reconstituted blood samples, the prior selective blockage of phosphatidylserine on RBC with annexin A5 enhanced glycoprotein VI-induced platelet procoagulant activity. For patients with anemia or erythrocytosis, cluster analysis revealed high or low whole-blood TG profiles in specific cases of anemia. The TG profiles lowered upon annexin A5 addition in the presence of RBCs and thus were determined by the extent of phosphatidylserine exposure of blood cells. Profiles for patients with polycythemia vera undergoing treatment were similar to that of control subjects. We concluded that RBC and platelets, in a phosphatidylserine-dependent way, contribute to the TG process. Determination of the whole-blood hypo- or hyper-coagulant activity may help to characterize a bleeding or thrombosis risk.

Molecular Mechanisms Underlying Vascular Liver Diseases: Focus on Thrombosis

Vascular liver disorders (VLDs) comprise a wide spectrum of clinical-pathological entities that primarily affect the hepatic vascular system of both cirrhotic and non-cirrhotic patients. VLDs more frequently involve the portal and the hepatic veins, as well as liver sinusoids, resulting in an imbalance of liver homeostasis with serious consequences, such as the development of portal hypertension and liver fibrosis. Surprisingly, many VLDs are characterized by a prothrombotic phenotype. The molecular mechanisms that cause thrombosis in VLD are only partially explained by the alteration in the Virchow's triad (hypercoagulability, blood stasis, and endothelial damage) and nowadays their pathogenesis is incompletely described and understood. Studies about this topic have been hampered by the low incidence of VLDs in the general population and by the absence of suitable animal models. Recently, the role of coagulation imbalance in liver disease has been postulated as one of the main mechanisms linked to fibrogenesis, so a novel interest in vascular alterations of the liver has been renewed. This review provides a detailed analysis of the current knowledge of molecular mechanisms of VLD. We also focus on the promising role of anticoagulation as a strategy to prevent liver complications and to improve the outcome of these 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).

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.

A multicenter analysis of the role of prophylactic transfusion of blood products in patients with cirrhosis and esophageal varices undergoing endoscopic band ligation

Background & Aims

Prophylactic administration of platelets and fresh frozen plasma (FFP) has been recommended in patients with cirrhosis with low platelets and/or prolonged international normalized ratio (INR) without scientific evidence to support this practice. In this analysis, we evaluated the use of prophylactic administration of blood products in outpatients with cirrhosis undergoing endoscopic band ligation (EBL).

Methods

This is a multicenter retrospective analysis of consecutive EBL procedures in patients with cirrhosis at 4 hospitals in Spain from 01/2010-01/2017. FFP and/or platelet transfusion were given at the discretion of the physician if INR was >1.5 and/or platelet count <50x10⁹/L. Patient demographics, endoscopic findings, bleeding events after EBL, and the use of prophylactic FFP or platelets were recorded.

Results

A total of 536 patients underwent 1,472 EBL procedures: 72% male; main etiology HCV and alcohol (72%); median MELD score 11; Child-Pugh A/B/C (59/33/8%). EBL procedures were performed for primary (51%) or secondary (49%) prophylaxis. A median of 2 procedures per patient were performed.^1-4 FFP and/or platelets were administered in 41 patients (7.6%). The prophylactic transfusion protocol was followed in 16% and 28% of procedures with high INR and/or low platelets, respectively. Post-EBL bleeding occurred in 26 out of 536 patients (4.8%) and in 33 out of 1,472 procedures (2.2%). Bleeding was due to post-EBL ulcers in 21 patients and due to band dislodgment in 5. In 6 patients, bleeding occurred within 24 hours and in the remaining patients it occurred within 2 weeks after EBL. In those that bled, 7 met criteria for transfusion (2 for FFP and 5 for platelets), of whom only 1 received FFP and 4 received platelets; the remaining 19 patients did not meet criteria for transfusion. There was no association between INR or platelet count and bleeding events. Univariate and multivariate analysis revealed that Child-Pugh and MELD scores were risk factors for post-EBL bleeding.

Conclusions

The incidence of post-EBL bleeding is low and is associated with advanced liver disease. Post-EBL bleeding was not related to baseline INR/platelet count and most outpatients with post-EBL bleeding did not meet criteria for prophylactic transfusion.

Lay summary

Patients with chronic liver disease or cirrhosis and enlarged veins (varices) of the esophagus that can potentially bleed commonly need an endoscopy to treat these varices with elastic rubber bands (endoscopic band ligation). Some patients have low platelet counts or prolonged coagulation tests. This analysis of 4 centers evaluated the use of prophylactic administration of blood products in outpatients with cirrhosis undergoing endoscopic band ligation. The results showed that bleeding after band ligation is uncommon and that if bleeding occurs it does not seem to be related with coagulation tests or the administration of blood products to prevent bleeding after band ligation of esophageal varices.

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Multicenter analysis of prophylactic administration of blood products in 536 outpatients with cirrhosis undergoing EBL.

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The prophylactic transfusion protocol was only followed in 16% and 28% of procedures with high INR and/or low platelets, respectively.

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Post EBL-bleeding occurred in 26 patients – 4.8% of patients and in 2.2% of procedures.

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Patients that bled had higher Child-Pugh and MELD scores compared to those that did not bleed.

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There was no clear relationship between post-EBL bleeding and the baseline INR/platelet count before the procedure.

Evaluation of Coagulation, Fibrinolysis and Endothelial Biomarkers in Cirrhotic Patients With or Without Portal Venous Thrombosis

To evaluate variations in coagulation, fibrinolysis and endothelial marker expression in cirrhotic patients and to explore their clinical value and predictive performance in cirrhotic patients with or without portal vein thrombosis (PVT), we performed a case-control study with 175 cirrhotic patients and 50 healthy individuals. 99 patients had PVT and another 76 patients did not. All participants were evaluated for plasma levels of conventional hemostatic markers. Thrombin-antithrombin complex (TAT), plasmin-α2-plasmin inhibitor complex (PIC), thrombomodulin (TM), tissue plasminogen activator inhibitor complex (t-PAIC), von Willebrand factor antigen (vWF: Ag) and coagulation factor Ⅷ (FⅧ: c) were also assessed and the ratio of TAT/t-PAIC was calculated. We analyzed differences in these biomarkers among the three groups and constructed receiver operating characteristic (ROC) curves. Patients with PVT exhibited significantly higher TAT and TAT/t-PAIC than cirrhotic patients without PVT (both P < 0.001). Areas under the curve (AUC) of ROC analyses for TAT and TAT/t-PAIC were 0.68 and 0.66, the cut-off levels were 1.55 ng/ml and 0.46, with sensitivities and specificities of 78.79% and 51.32% regarding TAT, 39.8% and 90.79% regarding TAT/t-PAIC. Levels of FⅧ: c and vWF: Ag in patients with PVT were significantly lower than those without PVT (p = 0.026 and p = 0.027, respectively). The AUC^ROC, cut-off level, sensitivity and specificity of FⅧ: c were 0.64, 111.1%, 66.67% and 60%, respectively. For vWF: Ag they were 0.61, 429%, 89.66% and 38.71%, respectively. Cirrhotic patients have disorders of coagulation, fibrinolysis and the endothelial system. TAT, TAT/t-PAIC, FⅧ: c and vWF: Ag can be used as potential biomarkers for predicting PVT in cirrhotic patients.

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.

Assessment of laboratory tests and intraoperative bleeding in patients with liver cirrhosis undergoing tooth extractions

OBJECTIVES

The objective of this study was to quantify intraoperative bleeding in patients with cirrhosis and correlate it with clinical characteristics and laboratory coagulation tests.

STUDY DESIGN

A case-control study was carried out with 74 patients with cirrhosis who were submitted to preoperative coagulation tests (complete blood count, platelet count, prothrombin time/international normalized ratio, thrombin time, activated partial thrombin time, platelet aggregation, fibrinogen, protein C, protein S, antithrombin, and von Willebrand factor level and activity). The levels of nitrogen compounds that can affect the platelet function were determined in saliva and blood by using automated enzymatic-colorimetric assays.

RESULTS

Patients with cirrhosis had changes in almost all coagulation tests. The average volumes of intraoperative bleeding and blood lost per minute in the study group (5.36 mL/min and 0.19 mL/min, respectively) were greater than those in the control group (3.05 mL/min and 0.11 mL/min, respectively; P < .05). In the control group, ascites (P = .012) and presence of periapical lesion (0.034) were positively correlated with bleeding (mL/min). With regard to coagulation tests and nitrogen compounds, only a positively moderate correlation with the platelet aggregation test was observed.

CONCLUSIONS

No patients had hemorrhagic events and it was not possible to correlate a greater amount of bleeding with coagulation tests or nitrogen compounds in the study group.

Thrombin Generation in Chronic Liver Diseases-A Pilot Study

The knowledge about coagulation disorders in patients with chronic liver disease changed in the last decade. The aim of this study was to analyze the parameters of thrombin generation in patients with chronic liver disease, as they are the most appropriate biomarkers to explore coagulation. (1) Background: The knowledge about coagulation disorders in patients with chronic liver disease changed in the last decade. The study of thrombin generation in patients with chronic liver disease provides a much more accurate assessment of the coagulation cascade; (2) Methods: This study is a prospective observational pilot study on hospitalized patients with chronic liver diseases that analyzed thrombin generation performed from their platelet-poor plasma versus that of control subjects. We analyzed a group of 59 patients with chronic liver disease and 62 control subjects; (3) Results: Thrombin generation was lower in hepatitis and cirrhosis patients compared to controls and decreases as the disease progressed. Lag time was higher in ethanolic etiology compared to the control group. Peak thrombin and endogenous thrombin potential were shorter in all etiologies when compared to the control group. The velocity index was significantly lower in HCV hepatopathies, ethanolic, and mixed etiology when compared with normal individuals; (4) Conclusions: Given the variability of thrombin generation in patients with chronic liver disease, its assay could serve to identify patients with high thrombotic and hemorrhagic risk and establish personalized conduct toward them.

Added Value of Blood Cells in Thrombin Generation Testing

The capacity of blood to form thrombin is a critical determinant of coagulability. Plasma thrombin generation (TG), a test that probes the capacity of plasma to form thrombin, has improved our knowledge of the coagulation system and shows promising utility in coagulation management. Although plasma TG gives comprehensive insights into the function of pro- and anticoagulation drivers, it does not measure the role of blood cells in TG. In this literature review, we discuss currently available continuous TG tests that can reflect the involvement of blood cells in coagulation, in particular the fluorogenic assays that allow continuous measurement in platelet-rich plasma and whole blood. We also provide an overview about the influence of blood cells on blood coagulation, with emphasis on the direct influence of blood cells on TG. Platelets accelerate the initiation and velocity of TG by phosphatidylserine exposure, granule content release and surface receptor interaction with coagulation proteins. Erythrocytes are also major providers of phosphatidylserine, and erythrocyte membranes trigger contact activation. Furthermore, leukocytes and cancer cells may be important players in cell-mediated coagulation because, under certain conditions, they express tissue factor, release procoagulant components and can induce platelet activation. We argue that testing TG in the presence of blood cells may be useful to distinguish blood cell-related coagulation disorders. However, it should also be noted that these blood cell-dependent TG assays are not clinically validated. Further standardization and validation studies are needed to explore their clinical usefulness.

Efficacy of pro- and anticoagulant strategies in plasma of patients undergoing hepatobiliary surgery

BACKGROUND

In vitro efficacy of pro- and antihemostatic drugs is profoundly different in patients with compensated cirrhosis and in those who have cirrhosis and are critically ill.

OBJECTIVES

Here we assessed the efficacy of pro- and anticoagulant drugs in plasma of patients undergoing hepato-pancreato-biliary (HPB) surgery, which is associated with unique hemostatic changes.

METHODS

We performed in vitro analyses on blood samples of 60 patients undergoing HPB surgery and liver transplantation: 20 orthotopic liver transplantations, 20 partial hepatectomies, and 20 pylorus-preserving pancreaticoduodenectomies. We performed thrombin generation experiments before and after in vitro addition of fresh frozen plasma (FFP), prothrombin complex concentrate (PCC), recombinant factor VIIa (rFVIIa), low molecular weight heparin (LMWH), unfractionated heparin, dabigatran, and rivaroxaban.

RESULTS

We showed that patients undergoing HPB surgery are in a hypercoagulable state by thrombin generation testing. FFP and rFVIIa had minimal effects on thrombin generation, whereas PCC had a more pronounced procoagulant effect in patients compared with controls. Dabigatran showed a more pronounced anticoagulant effect in patients compared with controls, whereas rivaroxaban and LMWH had a decreased anticoagulant effect in patients.

CONCLUSION

We demonstrate profoundly altered in vitro efficacy of commonly used anticoagulants, in patients undergoing HPB surgery compared with healthy controls, which may have implications for anticoagulant dosing in the early postoperative period. In the correction of perioperative bleeding complications, PCCs appear much more potent than FFP or rFVIIa, and PCCs may require conservative dosing and caution in use in patients undergoing HPB surgery.

Primary Hemostasis in Chronic Liver Disease and Cirrhosis: What Did We Learn over the Past Decade?

Changes in primary hemostasis have been described in patients with chronic liver disease (CLD) and cirrhosis and are still subject to ongoing debate. Thrombocytopenia is common and multifactorial. Numerous studies also reported platelet dysfunction. In spite of these changes, primary hemostasis seems to be balanced. Patients with CLD and cirrhosis can suffer from both hemorrhagic and thrombotic complications. Variceal bleeding is the major hemorrhagic complication and is mainly determined by high portal pressure. Non portal hypertension-related bleeding due to hemostatic failure is uncommon. Thrombocytopenia can complicate management of invasive procedures in CLD patients. Recently, oral thrombopoietin agonists have been approved to raise platelets before invasive procedures. In this review we aim to bundle literature, published over the past decade, discussing primary hemostasis in CLD and cirrhosis including (1) platelet count and the role of thrombopoietin (TPO) agonists, (2) platelet function tests and markers of platelet activation, (3) von Willebrand factor and (4) global hemostasis tests.

Whole blood thrombin generation profiles of patients with cirrhosis explored with a near patient assay

BACKGROUND AND AIMS

Patients with cirrhosis have a rebalanced hemostasis, often with normal or elevated thrombin-generating (TG) capacity in plasma. Whole blood (WB) TG allows faster determination and, importantly, includes the influence of all circulating blood cells. We aimed to study the TG profile of patients with cirrhosis in WB and in platelet poor plasma.

METHODS

Thrombin-generating capacity in WB and plasma were assessed with a near-patient WB-TG assay and the calibrated automated thrombinography assay, respectively. TG assays were tested in presence and absence of thrombomodulin. Conventional coagulation tests were also performed.

RESULTS

Thirty-four patients with cirrhosis and twenty-two controls were analyzed. Compared with controls, patients had substantially deranged results in conventional coagulation tests. Comparable WB-TG capacity (endogenous thrombin potential until peak, ETPp) but significantly lower peak thrombin were found in patients, and these results persisted when thrombomodulin was present. TG of the patients was more resistant to thrombomodulin than controls in both WB and plasma, although the inhibitory effect of thrombomodulin was drastically weaker in WB than in plasma. The peak of WB-TG in patients correlated moderately with their hematocrit and platelet count. Significant correlations were found between TG results in WB and plasma.

CONCLUSIONS

The WB-TG assay shows a normal to hypocoagulable state in patients with cirrhosis with a decreased anticoagulant activity of TM compared to plasma-TG. The clinical value of this assay needs further validation.