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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.

Recombinant human soluble thrombomodulin (ART-123) is an anticoagulant and anti-inflammatory agent clinically used for treatment of disseminated intravascular coagulation. Preclinical studies have shown that ART-123 reduces hepatic ischemia/reperfusion. Although ART-123 may therefore have clinical benefit in orthotopic liver transplantation, the substantial alterations in the hemostatic system may complicate its use in this setting. Here, we studied the in vitro effect of ART-123 on coagulation of patients with end-stage liver disease undergoing liver transplantation. Ten patients with end-stage liver disease undergoing liver transplantation were included in this study. Plasma samples of 10 healthy individuals were included to establish reference values. Different concentrations of ART-123 were added to plasma samples, and peak thrombin generation and clot lysis times (CLTs) were determined. In patient samples, plasma was profoundly resistant to the anticoagulant action of ART-123, as reflected by significantly higher median inhibitory concentration (IC50 ) values of peak thrombin generation compared with controls. This might be partially explained by low levels of protein C, protein S, and elevated levels of factor VIII during transplantation. Intraoperative levels of thrombin activatable fibrinolysis inhibitor were significantly lower when compared with controls. However, ART-123-dependent prolongation of CLTs was not significantly different from healthy controls. In conclusion, this study suggests that ART-123 is unlikely to provoke bleeding in patients undergoing liver transplantation because proposed clinical dosages have a virtually absent anticoagulant effect in these patients. Clinical studies are required to confirm the safety of ART-123 and efficacy on alleviating ischemia/reperfusion injury during liver transplantation.

BACKGROUND & AIMS: A simultaneous decline in pro- and anticoagulant drivers in patients with liver diseases results in a "rebalanced" haemostatic system, even in acutely ill patients. Nevertheless, both bleeding and thrombotic events are common. Here, we explored efficacy of pro- and antihaemostatic strategies in compensated and acutely ill cirrhotics which may be unpredictable given the profound haemostatic changes.METHODS: We tested the effects in vitro of the addition of clinically relevant doses of commonly used pro- and antihaemostatic strategies in plasma from healthy individuals (n = 30) and patients with compensated (n = 18) and acutely decompensated cirrhosis (n = 18), and acute-on-chronic liver failure (n = 10). We used thrombin generation tests and fibrin clot permeability assays to assess potency of various approaches.RESULTS: Fresh frozen plasma and recombinant factor VIIa modestly increased thrombin generation (10%-20%). Prothrombin complex concentrate increased thrombin generation two-fold in controls and 2-4-fold in patients. Clot permeability decreased after addition of fibrinogen concentrate by 51% in controls and by 50%-60% in patients. Low molecular weight heparin decreased thrombin generation by 18% in controls and by 23%-54% in patients. Similarly, dabigatran decreased thrombin generation by 33% in controls and by 47%-100% in patients. In contrast, rivaroxaban decreased thrombin generation by 55% in controls, but only by 11%-38% in patients.CONCLUSIONS: These in vitro data suggest little prohaemostatic effect of fresh frozen plasma and recombinant factor VIIa in acutely ill cirrhotics, whereas prothrombin complex concentrate and fibrinogen concentrate clearly improved haemostasis. Furthermore, our data suggest the requirement for dose adjustments of commonly used anticoagulants in these patients.

Hepatobiliary surgery is a well-known risk factor for thrombotic complications but is also associated with substantial perioperative blood loss. Given the central role of the liver in hemostasis, hepatobiliary surgery is frequently accompanied by complex changes in the hemostatic system. Increasing knowledge of these changes has resulted in an improved understanding of the etiology of some of the hemostatic complications. In the early postoperative period a prolongation of conventional coagulation test times, such as the prothrombin time, is frequently seen. Together with a decreased platelet count, this suggests a hypocoagulable state. The concomitant decline of anticoagulant factors and development of a von Willebrand factor/ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) imbalance, however, suggest a hypercoagulable state, potentially contributing to the risk of thromboembolism. Postoperative thromboprophylaxis should be initiated early to avoid thrombosis, and intensified prophylaxis might benefit high-risk patients. The risk of hemorrhagic complications during hepatobiliary surgery has diminished over time, mainly due to improved surgical and anesthesiological techniques. However, bleeding can still be profound in individual patients and is difficult to predict using (global) hemostasis tests. A restrictive transfusion and fluid infusion policy to maintain a low central venous pressure is crucial in prevention of perioperative bleeding. However, when active bleeding occurs, proactive prohemostatic management is required.

Background and Aim Patients with cirrhosis may acquire profound changes in haemostasis. Although haemostatic changes in cirrhosis have been extensively studied, most studies were performed in groups of patients with mixed aetiology. As thrombotic events appear more common in some aetiologies of disease, notably non-alcoholic steatohepatitis (NASH) and cholestatic disease, we hypothesized that haemostatic changes might be different across aetiologies. Patients and Methods We studied 109 patients with cirrhosis (31 cholestatic liver disease, 23 NASH, 37 alcoholic liver disease [ALD], 18 viral hepatitis) and 44 healthy controls. Patients with malignancy were excluded. Routine diagnostic tests of haemostasis, thrombin generation assays, fibrin permeability assays and a plasma-based fibrinolytic assay were performed. Results All patients had comparable severity of disease according to their Model for End-Stage Liver Disease score (9 [7–11]). Plasma levels of von Willebrand factor were substantially elevated across all aetiologies, with a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13 levels comparable to controls. Thrombin generation capacity was elevated in all aetiologies, most profoundly in ALD. Fibrin permeability was decreased in all aetiologies, which was accompanied by elevated fibrinogen levels. Clot lysis times were prolonged in NASH and cholestatic disease. Plasma levels of individual proteins were similarly altered in all aetiologies. Conclusion Our in-depth haemostatic profiling of primary, secondary and tertiary haemostasis in a group of patients with Childs–Turcotte–Pugh A/B cirrhosis showed no large differences between aetiologies, and was consistent with a general hypercoagulable profile in patients with mild cirrhosis. These results suggest that patients with cirrhosis have an increased risk of thrombosis, irrespective of their aetiology.

BACKGROUND & AIMS: Patients undergoing liver transplantation have complex changes in their hemostatic system, and the net effect of these changes appears a 'rebalanced' hemostatic profile. Recently, a process called NETosis, in which a neutrophil expels DNA and proteins that form a web-like structure, has been described as a mechanism of pathogen entrapment. Increasing evidence suggests a pivotal role for neutrophil extracellular traps (NETs), and their main component cell-free DNA in activation of coagulation. As liver transplantation is associated with substantial (hepatocyte) cell death and intrahepatic neutrophil accumulation, NETs might play an important role in the hemostatic balance during liver transplantation. Here, we determined markers for NETs in plasma of patients undergoing a liver transplantation and examined their association with activation of coagulation.METHODS: Markers for NETs and markers for activation of coagulation were determined in serial plasma samples taken from patients undergoing a liver transplantation (n=21) and compared with plasma levels in healthy controls.RESULTS: We found perioperative increases of markers for NETs with levels of cell-free DNA and nucleosomes that peaked after reperfusion, and myeloperoxidase-DNA complexes that peaked during the anhepatic phase. Cell-free DNA and nucleosome levels, but not MPO-DNA levels correlated with prothrombin fragment 1+2 and thrombin-antithrombin complex levels, which are established markers for activation of coagulation. Neutrophils undergoing NETosis were observed by immunostainings in post-reperfusion biopsies.CONCLUSIONS: Although NETosis occurs during liver transplantation, the majority of circulating DNA appears to be derived from cell death within the graft. The perioperative increases in cell-free DNA and nucleosomes might contribute to the complex hemostatic rebalance during liver transplantation. This article is protected by copyright. All rights reserved.

BACKGROUND: Vitamin K antagonist (VKA) therapy is safer and more effective when patients have a high time within the therapeutic range and low international normalised ratio variability. The SAMe-TT2R2 score aims to identify those at risk for poor VKA control.OBJECTIVES: To evaluate the predictive value and clinical usefulness of the SAMe-TT2R2 score to identify those at risk for poor VKA control.METHODS: We performed a systematic review in MEDLINE and Embase for original research papers assessing the SAMe-TT2R2's relation to poor TTR. We performed a meta-analysis where scores ≥ 2 and ≥ 3 predicting TTR < 70%. When studies evaluated other cutoffs for TTR or SAMe-TT2R2, they were harmonised by multiple simulations with patient characteristics from the individual studies, if the data were available.RESULTS: 16 studies were identified and used in the meta-analysis: 4 and 2 times directly, 8 and 8 times harmonised for scores ≥ 2 and ≥ 3, respectively (not all studies provided information about both cutoffs). The sensitivities and specificities were too heterogeneous to pool. The positive likelihood ratios were 1.25 (1.14-1.38) for a score ≥ 2, and 1.24 (1.09-1.40) for a score ≥ 3; the negative ones were 0.87 (0.82-0.93) and 0.96 (0.91-1.02), respectively. This shows that the post-test probabilities hardly differ from the prior probability (prevalence).CONCLUSION: The SAMe-TT2R2 score does predict low TTR, but the effect is small. Its effect on individual patients is too limited to be clinically useful.

• In vitro potency of common anticoagulants differs substantially between patients with cirrhosis and controls.

Nephrolithiasis is a frequent problem that can cause serious morbidity. When associated with an underlying metabolic disorder the recurrence rate is higher. Hypocitraturia is estimated to be present in 20-60% of cases. Several secondary causes are known. Potassium citrate is the primary treatment. In the case we present here we emphasise the need for metabolic screening, focussing on hypocitraturia, a less well-known cause of nephrolithiasis.

Background Malignant hypertension is frequently complicated by renal insufficiency. Although the survival of this hypertensive emergency has improved, recent data on renal outcome and its predictors are lacking. We assessed renal outcome and its predictors in patients with malignant hypertension. Methods Retrospective analysis of patients admitted with malignant hypertension in Amsterdam, the Netherlands between August 1992–January 2010. Follow-up data on vital status, renal function and blood pressure (BP) were obtained from the outpatient department and from general practitioners. The primary composite endpoint was end-stage renal disease (ESRD) defined as the start of kidney replacement therapy (KRT) or ≥ 50% decline of estimated glomerular filtration rate (eGFR). The secondary endpoint was all cause mortality. Results A total of 120 patients admitted with malignant hypertension were included. After a median follow-up period of 67 months (IQR 28 to 108 months) the primary endpoint was reached by 37 (31%) patients, whereas 18 patients (15%) reached the secondary endpoint. Twenty-nine (24%) patients started KRT and 8 patients (7%) had an eGFR decline ≥ 50%. After the acute phase (> 3 months after admission), initial serum creatinine and follow-up BP were the main predictors of future ESRD with hazard ratios of 6.1 (95% CI, 2.2–17) for patients with initial serum creatinine ≥ 175 μmol /L and 4.3 (95% CI, 1.4–14) for patients with uncontrolled hypertension. Conclusions Progressive renal function decline leading to ESRD remains a major threat to patients with malignant hypertension. BP control during follow-up was an important modifiable predictor of renal outcome.

This study investigated the relation between alcohol consumption and the risk of cardiovascular disease (CVD) among 10 530-hypertensive women from the EPIC-NL cohort. Alcohol consumption was assessed using a validated food-frequency questionnaire and participants were followed for occurrence of CVD. During 9.4 years follow-up, we documented 580 coronary heart disease (CHD) events and 254 strokes, 165 of which were ischemic. An inverse association (P trend = 0.009) between alcohol consumption and risk of CHD was observed with a multivariate-adjusted hazard ratio of 0.72 (95% confidence interval: 0.52-1.01) for those consuming 70-139.9 g alcohol/week compared to lifetime abstainers. Of different beverages, only red wine consumption was associated with a reduced risk of CHD. A U-shaped relation (P = 0.08) was observed for total stroke with a hazard ratio of 0.65 (0.44-0.95) for consuming 5-69.9 g alcohol/week compared with lifetime abstainers. Similar results were observed for ischemic stroke with a hazard ratio of 0.56 (0.35-0.89) for consuming of 5-69.9 g alcohol/week. We conclude that moderate alcohol consumption is associated with a reduced risk of CHD among hypertensive women. Light alcohol consumption tended to be related to a lower risk of stroke. Current guidelines for alcohol consumption in the general population also apply to hypertensive women.