Coagulation defects in liver disease

Recognizing skin conditions in patients with cirrhosis: a narrative review

Background: The skin is a major target organ for extrahepatic manifestations of liver diseases, and dermatologic abnormalities are common in patients with hepatic disorders. Clinical examination of the skin, nails and hair can allow for appropriate recognition, early diagnosis and treatment of liver diseases, and improvement in the quality of life and life expectancy of affected patients.Methods: We searched 3 databases (Pubmed,Medline and Embase) and selected studies about cirrhosis related skin manifestations and their pathophysiology.Results: A total of 73 articles were included in the review. Studies displayed the spectrum of cutaneous manifestations related to hormonal and vascular changes as well as nail and hair changes in patients with cirrhosis and/or portal hypertension.Conclusion: Cutaneous alterations are important clues or potential indications in the diagnosis of liver cirrhosis. Familiarity with skin conditions can be promptly diagnosed and appropriate management initiated.KEY MESSAGESManifestations of the liver and skin disorders are interrelated in various ways. Cutaneous changes may be the first clue that a patient has liver disease.The skin is a major target organ for extrahepatic manifestations of liver diseases. A broad range of cutaneous alterations can be present in patients with cirrhosis, such as vascular, nail, hair, hormonal changes, etc.Recognizing these signs is crucial so that potential underlying diseases including liver disease can be promptly diagnosed and appropriate management timely initiated.

Endothelium, Platelets, and Coagulation Factors as the Three Vital Components for Diagnosing Bleeding Disorders: A Simplified Perspective with Clinical Relevance

Bleeding disorders are a major group of hematological disorders, which are highly prevalent in the world. Excessive bleeding can result in serious consequences including hypoperfusion and cardiac arrest. The body has its selfmechanism to control excessive bleeding which is termed hemostasis. Hemostasis is achieved in two major steps, the formation of the primary and secondary hemostatic plugs. Endothelium, platelets, and coagulation factors are three components involved in hemostasis. Endothelium and platelets have a major role in forming the primary hemostatic plug. Consequently, the first step in investigating a bleeding disorder is platelet count. Despite normal platelet count, abnormality in the primary hemostatic plug may arise due to functional defects of the platelets including adhesion, activation, and aggregation. Von Willebrand disease (VWD) is an endothelial defect and the most prevalent inherited defect in coagulation. Abnormalities in the secondary hemostatic plug are largely due to coagulation factor deficiencies, and, to a lesser extent, the presence of inhibitors. Techniques involving viscoelastics have been aiding in rapid diagnosis and are useful in point-of-care testing. This article discusses the investigation of bleeding disorders from the perspective of the endothelium, platelet, and coagulation factor physiology. These three components should be properly investigated to achieve the definitive diagnosis of bleeding disorders.

Spontaneous Bilateral Subdural Hematomas in a Patient With Cryptogenic Liver Cirrhosis

Spontaneous subdural hematoma (SDH) in cirrhotic patients is a rarely described condition in the literature and carries a high mortality rate. Several factors can potentially contribute to SDH development in cirrhosis, including coagulation cascade defects, thrombocytopenia, arteriovenous malformations, and cerebral atrophy. Clinicians should always keep spontaneous development of SDH in the differential diagnosis of acute encephalopathy in patients with end-stage liver disease, and prompt head imaging should be considered. We report a unique case of a 64-year-old patient with cryptogenic liver cirrhosis who was found to have spontaneous, bilateral SDHs while undergoing workup for acute encephalopathy.

Interference of Monoclonal Gammopathy with Fibrinogen Assay Producing Spurious Dysfibrinogenemia

Abnormal coagulation properties indicative of a dysfibrinogenemia were found in the plasma of an asymptomatic 65-year-old male. An immunoglobulin k light chain was found to interfere with Fg functional assay and coagulation tests (activated partial thromboplastin time, prothrombin time, and thrombin time). Steroid therapy reduced the inhibitory effect (after dexamethasone treatment coagulation test and functional Fg value normalized). Spurious dysfibrinogenemia associated with light chain monoclonal gammopathy of undetermined significance was diagnosed.

Increased risk of subdural hematoma in patients with liver cirrhosis

BACKGROUND

Subdural hematoma (SDH) is associated with a high mortality rate. The risk of SDH in cirrhotic patients has not been well studied.

AIM

The aim of the study was to examine the risk of SDH in cirrhotic patients.

DESIGN

A retrospective study from a universal insurance claims database of Taiwan.

METHODS

A cohort of 9455 liver cirrhotic patients from 2000 to 2011 and an age-and sex-matched control cohort of 35992 subjects without cirrhosis were identified. The severity of liver cirrhosis was classified into uncomplicated and complicated according to presence of complications or not. The incidence and hazard ratio of SDH were measured by the end of 2011.

RESULTS

The mean follow-up years were 4.34 ± 3.45 years in the cirrhosis cohort and 6.36 ± 3.28 years in the non-cirrhosis cohort. The incidence of SDH was 2.73-fold higher in the cirrhosis cohort than in the control cohort (29.3 vs. 10.9 per 10 000 person-years), with an adjusted hazard ratio of 2.73 (95% CI = 2.19-3.42), 2.42 (95% CI = 1.89-3.08), and 5.07 (95% CI = 3.38-7.60) in the all liver cirrhosis, the uncomplicated liver cirrhosis, and the complicated liver cirrhosis patients compared to the control cohort. The adjusted hazard ratios were 2.65 (95% CI = 2.06-3.41) for traumatic SDH and 3.09 (95% CI 1.91-5.02) for non-traumatic SDH in liver cirrhosis patients, compared to the controls.

CONCLUSIONS

This study demonstrates that patients with cirrhosis are at higher risk of both traumatic and non-traumatic SDH than individuals without cirrhosis. The risk increases further in patients with complicated liver cirrhosis.

Use of recombinant factor VII for tooth extractions in a patient with severe congenital factor VII deficiency: a case report

BACKGROUND AND OVERVIEW

Patients with factor VII deficiency have an increased risk of prolonged perioperative hemorrhage. In this article, the authors present a case of severe factor VII deficiency in a patient who required tooth extraction.

CASE DESCRIPTION

A 44-year-old woman with severe congenital factor VII deficiency sought care for a symptomatic, carious, and nonrestorable maxillary right second molar that required extraction. The authors obtained hematologic consultation, and the patient underwent the extraction under general anesthesia in the inpatient setting. Perioperative management included performing relevant laboratory studies, preoperative recombinant factor VII infusion, and postoperative intravenous aminocaproic acid administration. No hemorrhagic complications occurred throughout the perioperative course.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

The degree of factor VII deficiency correlates poorly with bleeding risk. Perioperative management is variable, requiring preoperative consultation with a hematologist.

Review of anesthesia in liver transplantation

Liver transplantation (LT) is a well-accepted treatment modality of many end-stage liver diseases. The main issue in LT is the shortage of deceased donors to accommodate the needs of patients waiting for such transplants. Live donors have tremendously increased the pool of available liver grafts, especially in countries where deceased donors are not common. The main ethical concern of this procedure is the safety of healthy donors, who undergo a major abdominal surgery not for their own health, but to help cure others. The first part of the review concentrates on live donor selection, preanesthetic evaluation, and intraoperative anesthetic care for living liver donors. The second part reviews patient evaluation, intraoperative anesthesia monitoring, and fluid management of the recipient. This review provides up-to-date information to help improve the quality of anesthesia, and contribute to the success of LT and increase the long-term survival of the recipients.

Impact of sustained virus elimination on natural anticoagulant activity in patients with chronic viral hepatitis C

Previous studies have reported reduced synthesis of various hemostatic factors in patients with chronic liver disease. Whether changes in plasma levels of these proteins reflect recovered liver synthetic function following virological eradication therapy has not been approved yet. The aim of the study was to determine the impact of sustained viral suppression achieved with pegylated interferon alpha and ribavirin on hemostatic parameters including natural anticoagulants in patients with chronic hepatitis C. The following coagulation screening tests were obtained in thirty patients with chronic viral hepatitis C before and after completion of antiviral treatment: activated partial thromboplastin time, prothrombin time, plasma fibrinogen and natural anticoagulant proteins antithrombin III, protein C (PC) and total protein S (PS) activity. Only patients who achieved durable virus suppression were included. The mean PC and PS levels were significantly lower in patients with chronic viral hepatitis C before antiviral therapy than in healthy controls (79.04 ± 16.19 % vs. 109.92 ± 21.33% and 54.04 ± 16.11% vs. 87.60 ± 8.15%, respectively; (p<0.001). Mean levels of PC exhibited a significant increase by 14.69 % after the completion of antiviral treatment (93.73 ± 14.18%, p<0.001) as well as PS levels, which significantly increased by 21.46% (75.50 ± 15.43, p<0.001) when compared with pre-treatment values. No remarkable fluctuations in other hemostatic parameters were noted. Protein C and protein S are sensitive markers of hepatocyte synthetic impairment and are valuable markers in monitoring the efficacy of antiviral treatment in chronic hepatitis C patients. Larger studies are needed to confirm our results.

Higher prognostic value of soluble fibrin complexes than D-dimer and fibrin degradation product for disseminated intravascular coagulation in patients with liver cirrhosis

Fibrin-related markers may help differentiate disseminated intravascular coagulation (DIC) from liver cirrhosis-associated dysfunctional coagulation. We investigated the significance of three fibrin-related markers [D-dimer, fibrin degradation product (FDP), and soluble fibrin complexes (sFC)] for the assessment of DIC status and prognosis. We classified 235 patients with suspected DIC into two groups according to their condition: the liver cirrhosis group (n = 47) and the no liver cirrhosis group (n = 188). Prothrombin time (PT), and fibrinogen, sFC, D-dimer, antithrombin, and protein C concentrations were measured and DIC scores were calculated using four parameters: platelet count, D-dimer, fibrinogen, and PT. In the liver cirrhosis group, the sFC concentration increased significantly in accordance with DIC score compared with the no liver cirrhosis group, and this increase was more prominent than D-dimer and FDP concentration increases. For the diagnosis of overt DIC in patients with liver cirrhosis, the area under the concentration curve (AUC) was larger for sFC (0.746) than for D-dimer (0.733) and FDP (0.687). Cox analysis also indicated that an elevated sFC concentration is a more significant prognostic factor of DIC than D-dimer or FDP (hazard ratio: 10.78; P = 0.036) in liver cirrhosis group; however, it was not a prognostic factor in the no liver cirrhosis group. sFC is a powerful diagnostic and prognostic marker of DIC in patient with liver cirrhosis. The use of sFC is expected to enhance the diagnosis and prognosis of DIC, particularly in patients with liver cirrhosis.

Recombinant Activated Factor VII in Patients at High Risk of Bleeding

Currently, recombinant activated factor VII (rFVIIa) (NovoSeven) is indicated for the treatment of spontaneous and surgical bleeding in congenital haemophilia A and B patients with inhibitors to factors VIII (FVIII) and IX (FIX) >5 Bethesda units (BU) worldwide, and in patients with acquired haemophilia, congenital FVII deficiency and Glanzmann's thrombasthenia in Europe. Until April 2003, almost three-quarters of a milion doses of rFVIIa have been administered proving its efficacy and excellent safety record. According to results from initial clinical trials and a large number of case reports, the rFVIIa may be effective not only in treating haemophilia patients but also in treatment of bleeding in patients on oral anticoagulation or heparin, patients with liver diseases, von Willebrand disease (vWD), thrombocytopenia, various platelet defects, congenital or acquired deficiency of FVII, and in subjects without any pre-existing coagulopathy with diffuse life-threatening bleeding triggered by surgery or trauma. This review will briefly summarize rFVIIa mode of action in haemostasis, the current clinical experience with rFVIIa and focus on the alternative use of rFVIIa in patients at the high risk of bleeding in both spontaneous cases and clinical trials reports.

Pharmacokinetics of Long-Acting Naltrexone in Subjects With Mild to Moderate Hepatic Impairment

Long-acting naltrexone is an extended-release formulation developed with the goal of continuous naltrexone exposure for 1 month for the treatment of alcohol dependence. The influence of mild and moderate hepatic impairment on naltrexone pharmacokinetics following long-acting naltrexone 190-mg administration was assessed. Subjects with mild (Child-Pugh grade A) and moderate (Child-Pugh grade B) hepatic impairment (n = 6 per group) and matched control subjects (n = 13) were enrolled. Naltrexone and 6beta-naltrexol concentrations were determined over a period of 63 days following a single intramuscular dose. Naltrexone and 6beta-naltrexol concentrations were detected in all subjects through 28 days. Total exposure (AUC(0-infinity)) of naltrexone and 6beta-naltrexol was similar across all groups. The long apparent half-lives of naltrexone and 6beta-naltrexol (5-8 days) were attributed to the slow release of naltrexone (long-acting naltrexone exhibits absorption rate-limited elimination or "flip-flop" kinetics); elimination was not altered in subjects with hepatic impairment. Based on pharmacokinetic considerations, the dose of long-acting naltrexone does not need to be adjusted in patients with mild or moderate hepatic impairment.

Hemostatic defects in liver and renal dysfunction

Multiple and complex abnormalities of hemostasis are revealed by laboratory tests in such common diseases as cirrhosis and end-stage renal insufficiency. Because these abnormalities are associated with a bleeding tendency, a causal relationship is plausible. Accordingly, an array of transfusional and nontransfusional medications that improve or correct these abnormalities is used to prevent or stop hemorrhage. However, recent data indicate that the use of hemostatic drugs is scarcely justified mechanistically or clinically. In patients with uremia, the bleeding tendency (mainly expressed by gastrointestinal bleeding and hematoma formation at kidney biopsy) is reduced dramatically by the improvement of anemia obtained with the regular use of erythropoietin. In cirrhosis, the most severe and frequent hemorrhagic symptom (acute bleeding from esophageal varices) is not explained by abnormalities in such coagulation screening tests as the prothrombin and partial thromboplastin times, because formation of thrombin the final coagulation enzyme is rebalanced by low naturally occurring anticoagulant factors in plasma that compensate for the concomitant decrease of procoagulants. Rebalance also occurs for hyperfibrinolysis and platelet abnormalities. These findings are consistent with clinical observations that transfusional and nontransfusional hemostatic medications are of little value as adjuvants to control bleeding in advanced liver disease. Particularly in uremia, but also in cirrhosis, thrombosis is becoming a cogent problem.

Normal to increased thrombin generation in patients undergoing liver transplantation despite prolonged conventional coagulation tests

BACKGROUND & AIMS

Patients with liver disease often show substantial changes in their hemostatic system, which may aggravate further during liver transplantation. Recently, thrombin generation in patients with stable disease was shown to be indistinguishable from controls provided thrombomodulin, the natural activator of the anticoagulant protein C system, was added to the plasma. These results indicated that the hemostatic balance is preserved in patients with liver disease, despite conventional coagulation tests suggest otherwise.

METHODS

Here we examined thrombin generation profiles in serial plasma samples taken from ten consecutive patients undergoing liver transplantation.

RESULTS

At all time points, the endogenous thrombin potential (ETP) was slightly lower compared to healthy volunteers, despite substantially prolonged PT and APTT values. However, when thrombin generation was tested in the presence of thrombomodulin, the ETP was equal to or even higher than that in healthy subjects. In fact, thrombin generation was hardly affected by thrombomodulin, while thrombin generation in healthy subjects decreased profoundly upon the addition of thrombomodulin. In patients undergoing liver transplantation, efficient thrombin generation in the presence of thrombomodulin may be explained by decreased levels of protein C, S, and antithrombin, and by elevated levels of FVIII.

CONCLUSIONS

Thrombin generation in patients undergoing liver transplantation is equal or even superior to thrombin generation in healthy volunteers when tested in the presence of exogenous thrombomodulin. These results support the recently advocated restrictive use of plasma during liver transplantation and warrants further study of the prophylactic use of anticoagulants to reduce thromboembolic complications after transplantation.

The effect of hepatectomy on coagulation: an evaluation by thromboelastography

OBJECTIVES

Liver has a major role in coagulation. The hemostatic derangements measured by the mostly used coagulation parameters as prothrombin time, activated partial thromboplastin time, and thrombocyte count do not always correlate with the bleeding associated with liver diseases and these factors do not measure the thrombotic risks. So, thromboelastography is used in new clinical and laboratory research. The aim of this study is to study the effect of different levels of hepatectomy on coagulation.

METHODS

Laparatomy, 40% hepatectomy, and 70% hepatectomy was performed in three different groups of rats. Prothrombin time, international normalized ratio, activated partial thromboplastin time, thrombocyte count, fibrinogen levels, and thromboelastography parameters were obtained at the 0, 6, and 24th hour of the study.

RESULTS

Fibrinogen level at the 24th hour was greater than the early hours in both of the hepatectomy groups. Prothrombin time and international normalized ratio values were significantly higher in hepatectomy groups than in the sham group. There were no statistically significant difference in the clotting time, clot formation time, alpha-angle, and maximum clot firmness values in any of the thromboelastography channels, in any of the study times, in between the sham, 40% hepatectomy, and 70% hepatectomy groups.

CONCLUSION

There is no difference between 40 and 70% hepatectomy when the coagulopathy is evaluated. The coagulation derangements as reflected by the increase in fibrinogen and prolongation of prothrombin time and activated partial thromboplastin time after hepatectomy were not supported by thromboelastography parameters in this study.

Thrombotic risk factors in patients with liver cirrhosis: correlation with MELD scoring system and portal vein thrombosis development

BACKGROUND/AIMS

Prognostic scores currently used in cirrhotic patients do not include thrombotic risk factors (TRFs). Predicting factors of portal vein thrombosis (PVT) development are still unknown. We wanted to describe TRFs as a function of liver disease severity using the MELD score and assess the role of local and systemic TRFs as predictors of PVT development in cirrhotic patients.

METHODS

One hundred consecutive patients with liver cirrhosis were included in the study. TRFs, D-dimers, MELD score, portal vein patency and flow velocity were evaluated in all subjects at baseline and every 6 months thereafter. Variables able to predict PVT development within 1 year were identified by means of multiple logistic regression.

RESULTS

The plasma levels of protein C and antithrombin were lower and the concentration of D-dimers was higher in patients with advanced disease. Plasma levels of antithrombin, protein C and protein S resulted significantly lower in PVT group at univariate analysis, but reduced portal vein flow velocity was the only variable independently associated with PVT development.

CONCLUSIONS

Lower concentrations of natural coagulation inhibitors are frequently detected in patients with liver cirrhosis. A reduced portal flow velocity seems to be the most important predictive variable for PVT development in patients with cirrhosis.

Management of Life-Threatening Hemorrhages and Unsafe Interventions in Nonhemophiliac Children by Recombinant Factor VIIa

The literature on the use of recombinant factor VIIa (rFVIIa), which was initially used in hemophiliac patients with inhibitors, for hemorrhages that cannot be managed with conventional methods or operations that cannot be performed safely is increasingly growing. This study presents a group of nonhemophiliac patients with hemorrhagic problems or hemorrhage risk for some interventions that were successfully resolved with the use of rFVIIa. The patient group was composed of 20 patients with different disorders resulting in similar results as hemorrhage or hemorrhage risk. Most of the patients were diagnosed with liver disorders primary or secondary to other diseases. The remaining cases were patients with leukemia, sepsis, intracranial hemorrhage, and burn. Some of the patients had multiple problems like a patient with liver disorder and intracranial hemorrhage or a leukemia patient with sepsis and disseminated intravascular coagulation. rFVIIa had been administered to the patients at dosages between 70 and 150 μg/kg up to 6 doses with 2-hour to 3-hour intervals. All the patients had benefited from the use of rFVIIa even though some of them died because of primary disease. This study shows that rFVIIa can be safely used in high-risk patients with a history of recurrent hemorrhage, for whom no improvement can be achieved in the hemostasis tests.

Spontaneous rupture of the lateral thoracic artery in patients with liver cirrhosis

Bleeding in patients with liver cirrhosis is primarily caused by gastroesophageal varix in association with extensive collateral circulation, portal hypertensive gastropathy, a Mallory-Weiss tear and peptic ulcer disease. The spontaneous rupture of an artery, as a result of coagulopathy, is extremely rare in patients with liver cirrhosis; however, we recently observed a case of a spontaneous rupture of the lateral thoracic artery in a 47 year-old male patient with alcoholic liver cirrhosis. The patient expired despite repeated transcatheter arterial embolization of the lateral thoracic artery and best supportive care. This is, to our knowledge, the first documented case of the spontaneous rupture of the lateral thoracic artery in a patient with liver cirrhosis.

Avoiding pitfalls: what an endoscopist should know in liver transplantation--part 1

Cirrhosis is associated with global homodynamic changes, but the majority of the complications are usually manifested through the gastrointestinal tract. Therefore, Gastrointestinal Endoscopy has become an important tool in the multidisciplinary approach in the management of these patients. With the ever growing number of cirrhotic patients requiring pre-transplant endoscopic management, it is imperative that the community endoscopists are well aware of the pathologies that can be potentially noted on Gastrointestinal Endoscopy. Their timely management is also considered to have the utmost importance in being able to stabilize the patient until their transfer to a Liver Transplant Center. The aim of this manuscript is to give a comprehensive update and review of various endoscopic findings that a non-transplant endoscopist will encounter in the pre-transplant setting.

Yeast and mammalian two-hybrid systems for studying protein-protein interactions

An important step in the analysis of protein function is identification of the interaction partners of each protein. The two-hybrid system has been widely used to identify and explore protein-protein interactions. By using various two-hybrid systems, numerous protein interactions that regulate apoptosis signaling have been discovered that reveal unexpected functions of cancer-relevant proteins. Methods for performing two-hybrid experiments using either yeast or mammalian cells will be described in this chapter.

Hemostasis and global fibrinolytic capacity in chronic liver disease

Accelerated fibrinolysis associated with liver disease can be demonstrated by various tests that are either nonspecific in liver disease or that demonstrate only an extrinsic pathway. In the present study we used a new method to assess the global fibrinolytic capacity (GFC) of both the intrinsic and extrinsic pathways in patients with chronic liver disease. Forty patients with the diagnosis of chronic liver disease were included in the study. Seventeen age-matched and gender-matched healthy control individuals were enrolled as a control group. The GFC was studied with semiquantitative macrolatex agglutination. The study population consisted of 40 patients with chronic liver disease (group 1, patients with chronic hepatitis; group 2, patients with cirrhosis; group 3, patients with hepatocellular carcinoma), mean age 53.3 +/- 13 years, and a control group (group 4) consisting of 17 healthy individuals (mean age 55 +/- 12.2 years). The GFC was significantly higher in patients than in control individuals (13.8 +/- 9 microg/ml, 13.6 +/- 11 microg/ml, 14.1 +/- 14 microg/ml, 1.9 +/- 2.2 microg/ml, respectively; P < 0.05). There was no difference between the patient groups (P > 0.05). There was a significant positive relationship between the GFC and the prothrombin time and activated partial thromboplastin time values (P < 0.05). A negative correlation was also observed between the GFC and thrombocyte counts (P < 0.05). In conclusion, our results suggest that patients with chronic liver disease have hyperfibrinolysis, as reflected by the increased GFC. Elucidation of the GFC in chronic liver disease can reflect the net fibrinolytic capacity of those patients who are prone to hyperfibrinolysis resulting in bleeding tendencies and hemorrhages.

Prophylactic and therapeutic use of recombinant activated factor VII in patients with cirrhosis and coagulation impairment

Patients with cirrhosis and impaired coagulation often pose major therapeutic problems during bleeding episodes or invasive procedures. Recombinant activated factor VII (rFVIIa), which has been licensed for the treatment of haemophilia patients with factor VIII or IX inhibitors, has been occasionally used in cirrhotic patients. We present five patients with cirrhosis and coagulopathy who received 1-4 recombinant activated factor VII infusions either prophylactically in order to safely undergo an invasive procedure or therapeutically in order to control a severe bleeding episode which did not respond to standard supportive care. In particular, recombinant activated factor VII infusions were given in two patients before a percutaneous liver biopsy, in one patient before teeth extraction and in two patients with haemoperitoneum after an invasive procedure. Infusions of recombinant activated factor VII achieved rapid correction of prothrombin time in all cases allowing the safe performance of invasive procedures or resulting in efficient control of the bleeding episode. In conclusion, recombinant activated factor VII seems to be a rather promising agent for the prevention or treatment of complications of haemostasis impairment in cirrhotic patients. However, its exact role in this setting needs to be evaluated within well-designed, controlled clinical trials.

Coagulation abnormalities in patients who have liver disease

The liver plays a central role in the maintenance of normal hemostatic function. Because liver disease alters pathways of coagulation and anticoagulation, patients who have advanced disease can experience severe bleeding or thrombotic complications. Complications of advanced liver disease may also contribute to bleeding or thrombosis. This article reviews and discusses the management of the most common coagulation problems encountered in patients who have end-stage liver disease, which are thrombocytopenia and impaired humoral coagulation as measured by prolongation of the prothrombin time and international normalized ratio.

Coagulopathy does not fully protect hospitalized cirrhosis patients from peripheral venous thromboembolism

OBJECTIVE

Despite the endogenous coagulopathy of cirrhosis, some patients with cirrhosis experience thrombophilic states. This study aims to determine the incidence and predictors of venous thromboembolism (VTE), such as deep vein thrombosis (DVT) and pulmonary embolism, in hospitalized patients with cirrhosis.

METHODS

A retrospective case-control study was performed in a tertiary-care teaching hospital over an 8-yr period. A total of 113 hospitalized patients with cirrhosis with a documented new VTE were compared to controls. Risk factors for VTE were determined using univariate and multivariate statistical analyses.

RESULTS

Approximately 0.5% of all hospitalized patients with cirrhosis had a VTE. Traditional markers of coagulation such as INR and platelet count were not predictive of VTE. In the univariate analysis, serum albumin level was significantly lower in cases than controls (2.85 vs. 3.10 g/dL, respectively, p = 0.01). In the multivariate analysis, serum albumin remained independently predictive of VTE, with an odds ratio of 0.25 (95% CI 0.10-0.56).

CONCLUSIONS

Approximately 0.5% of admissions involving cirrhosis patients resulted in a new thromboembolic event. Low serum albumin was strongly predictive of increased risk for developing VTE, independent of international normalized ratio or platelet count. Serum albumin deficiency may indicate low levels of endogenous anticoagulants.

Safety and hemostatic effect of recombinant activated factor VII in cirrhotic patients undergoing partial hepatectomy: a multicenter, randomized, double-blind, placebo-controlled trial

BACKGROUND

Coagulopathy caused by cirrhosis may contribute to excessive bleeding during hepatectomy. We evaluated the hemostatic effect and safety of recombinant factor VIIa (rFVIIa) in cirrhotic patients undergoing partial hepatectomy.

METHODS

Patients were randomized to rFVIIa 50 or 100 mug/kg or placebo, administered intravenously 10 minutes before surgery and every second hour during surgery. The primary efficacy end points were the proportion of patients receiving red blood cell (RBC) transfusions and the amount of RBCs transfused. The RBC transfusion trigger was blood loss of 500 mL. Safety end points included thromboembolic and adverse events.

RESULTS

No statistically significant effect of rFVIIa treatment on efficacy end points was observed. Serious and thromboembolic adverse events occurred at similar incidences in the study groups.

CONCLUSIONS

Using blood loss as a transfusion trigger, the efficacy of rFVIIa in reducing the requirement for RBC transfusion was not established in this study. No safety concerns were identified.

Emerging Off-Label Uses for Recombinant Activated Factor VII: Grading the Evidence

Recombinant activated factor VII (rFVIIa) is currently licensed in the United States for treatment of bleeding episodes in patients with deficiencies of factor VIII (FVIII) or IX (FIX) who are refractory to factor replacement because of circulating inhibitors. A 1999 report of its successful use to stop what was deemed to be lethal hemorrhage after an abdominal gunshot wound in a young soldier without pre-existing coagulopathy has prompted exploration of other uses for rFVIIa. The virtual explosion of proposed uses of rFVIIa raises issues not only regarding our understanding of the coagulation system, but also regarding its efficacy, cost-effectiveness, and safety.

Haemostatic abnormalities in liver disease: could some haemostatic tests be useful as liver function tests?

The liver plays a central role in haemostasis, being the site of synthesis of most of the clotting factors, coagulation inhibitors and fibrinolytic parameters, in addition to its clearance of activated clotting and fibrinolytic factors. Nonetheless, no haemostatic test(s) is included among the routine liver function tests and this study aims to probe this possibility. The liver disease group (n=258) included acute hepatitis (n=25), chronic viral hepatitis (n=128), hepatitis B (HB) carriers (n=25), liver cirrhosis (n=67), and hepatocellular carcinoma (HCC) (n=13). The prothrombin time was significantly prolonged in acute hepatitis, liver cirrhosis and HCC. However, the reptilase time was prolonged in all the groups except in HB carriers, while the thrombin time was prolonged only in the HCC group. Antithrombin III and protein C levels exhibited significant reduction in acute hepatitis, liver cirrhosis and HCC. On the other hand, protein S levels (total and free) were reduced significantly in all the patients groups, including HB carriers when compared with healthy controls. Derangement of haemostatic tests is a common feature in liver disease, being most significant in acute hepatitis, liver cirrhosis and hepatocellular carcinoma. The most sensitive markers of hepatocyte malfunction are protein S (total and free) and the reptilase time as they were abnormal, in the mildest liver affections, when other biochemical tests as well as other haemostatic tests were normal. Further studies are needed to see whether these two tests qualify for inclusion among the routine liver function tests.

The management of coagulopathy and blood loss in liver surgery

Liver surgery has long been associated with massive perioperative blood loss and high rates of postsurgery morbidity and mortality. Recent advances in our knowledge of hepatic segmental anatomy have led to the evolution of liver resection, and a growing awareness of the coagulopathy present in cirrhotic patients has produced a greater understanding of the factors influencing surgical hemostasis. This review will examine the risk factors for perioperative hemorrhage in liver disease patients, and will describe current pharmacological, surgical, and radiological methods available for controlling bleeding and achieving effective hemostasis during liver resection and orthotopic liver transplantation (OLT). The potential role of recombinant factor VIIa (rFVIIa) in providing safe hemostasis during such procedures will also be explored. Today, due to careful monitoring and correction of coagulopathy, improved surgical techniques, and judicious patient selection, liver surgery is no longer a high-risk specialty with an unfavorable risk profile, but a safe and widely practiced procedure.

Recombinant activated factor VII (rFVIIa) as a hemostatic agent in liver disease: a break from convention in need of controlled trials

The management of coagulopathy in patients with acute and chronic liver disease has undergone little change in many years despite advances in our understanding of the pathogenesis of this problem. In general, deficiency of clotting factors as a result of poor hepatic synthetic function accounts for most of the coagulopathy. However, other processes such as disseminated intravascular coagulation (DIC), hyperfibrinolysis, dysfibrinogenemia, hemolysis, and a decrease in number or function of platelets may be present and thus add to the complexity of the problem. Coexisting portal hypertension and the associated risks of volume expansion, renal failure, and endothelial dysfunction add even more difficulty to the management of these patients. The clinician's despair is only exacerbated by uncertainty regarding the significance of laboratory indices of coagulation and the lack of agreement between health care providers regarding how to use these indices. Simple, conventional interventions such as vitamin K or plasma administration often produce only limited amelioration, and the latter carries the potential disadvantage of volume overexpansion as well as the risk of infection and transfusion reactions. Into this complex and uncertain clinical situation has arrived the antihemophilic agent recombinant activated factor VII (rFVIIa). Its development has led to a fundamental re-evaluation of the classic understanding of the normal clotting cascade. Moreover, use of this product in liver disease patients is increasing despite the lack of definitive studies or literature to guide therapy. Herein we review the mechanism of action of this agent, report the clinical applications in patients with liver disease, address the limitations and risks associated with the drug, and discuss the issue of its cost-effectiveness.

Profound imbalance of pro-fibrinolytic and anti-fibrinolytic factors (tissue plasminogen activator and plasminogen activator inhibitor type 1) and severe bleeding diathesis in a patient with cirrhosis

A 49-year-old male with alcoholic cirrhosis suffered several spontaneous, life-threatening, deep muscle bleeding episodes. Laboratory evaluation indicated excessive fibrinolysis with low plasminogen, low alpha2-antiplasmin, undetectable plasminogen activator inhibitor type 1 (PAI-1) activity, high tissue plasminogen activator (t-PA) activity and high t-PA antigen. Treatment with oral anti-fibrinolytic agents prevented further bleeding episodes. Decompensated cirrhosis eventually necessitated orthotopic liver transplantation. Post-operatively, the patient did not require oral anti-fibrinolytic agents, and there were no significant bleeding events. Circulating PAI-1 activity, t-PA activity and antigen normalized by 3 months post transplant. In short, the profound bleeding diathesis, as well as the imbalance in t-PA and PAI-1 levels, corrected after liver transplantation. Recognition of such patients is important, because the bleeding diathesis is an indication rather than a contraindication for orthotopic liver transplantation.

Cryoprecipitate for the correction of coagulopathy associated with liver disease

In patients with liver disease at risk of pulmonary oedema, cryoprecipitate (small volume) might be a viable alternative to fresh frozen plasma (FFP, large volume) in the correction of coagulopathy. However, the efficacy of cryoprecipitate in these patients has not been tested. We evaluated the role of cryoprecipitate in the correction of the coagulopathy of liver disease. To establish initial evidence of efficacy, six consecutive patients with hepatic failure and coagulopathy received five units of cryoprecipitate. Then, using a crossover design, 11 consecutive patients were randomized to receive either four units of FFP or five units of cryoprecipitate. Pre and post infusion International Normalized Ratio (INR), activated Partial Thromboplastin Time (aPTT), fibrinogen D-dimers, Factors V and IX, and reptilase time were measured. In the first six patients, cryoprecipitate improved the INR, aPTT and fibrinogen concentration (P = 0.03). In the crossover study, FFP administration produced a greater improvement in INR (P = 0.007) and aPTT (P = 0.005) than cryoprecipitate. However, there were no differences in any of the other measured variables. One patient developed acute pulmonary oedema while receiving FFP. Cryoprecipitate improves the coagulopathy of liver disease. Four units of FFP are more efficacious than five units of cryoprecipitate. Cryoprecipitate may have a role in correction of the coagulopathy associated with liver disease where concerns about pulmonary oedema exist.

Role of fresh frozen plasma infusion in correction of coagulopathy of chronic liver disease: a dual phase study

OBJECTIVE

Fresh frozen plasma infusions are commonly used to correct the prolonged prothrombin time in patients with advanced chronic liver disease. The aim of this study was to establish how frequently this treatment is effective in correcting this coagulopathy.

METHODS

A split retrospective-prospective study design was employed. In the retrospective series, 80 patients were identified with prolongation of the prothrombin time who received fresh frozen plasma infusions. In the prospective arm, 20 patients were included. All patients had confirmed chronic liver disease and showed no response to vitamin K injections. None of the patients had evidence of disseminated intravascular coagulation. The indications for infusion of fresh frozen plasma, number of units administered, complications, and percentage of patients who corrected their prothrombin time to less than 3 s longer than control time were recorded.

RESULTS

The majority of patients (75%) received 2-4 units of fresh frozen plasma. The mean prothrombin time was numerically improved by the infusion of 2-6 units of fresh frozen plasma. However, using correction to less than 3 s longer than control time as an endpoint, only 12.5% of the retrospective and 10% of the prospective study groups respectively had correction of their coagulopathy. Only one complication of infusion of plasma was noted during the course of the study.

CONCLUSIONS

Our results reiterate previous observations made more than 45 yr ago, that fresh frozen plasma infusions using the number of units commonly employed in clinical practice infrequently correct the coagulopathy of patients with chronic liver disease. Higher volumes (6 or more units) may be more effective but are rarely employed.

Effects of recombinant activated factor VII on coagulation measured by thromboelastography in liver transplantation

Besides the conventional laboratory tests, thromboelastography (TEG) is used to monitor hemostasis during liver transplantation. A previous pilot study suggested a beneficial effect of recombinant activated factor VII (rFVIIa) on transfusion requirements in liver transplantation. In the present study, we assess the effects of rFVIIa on coagulation variables and TEG. In six study patients, the prothrombin time (PT), the activated partial thromboplastin time (aPTT) and TEG variables [reaction time (r), kinetic time (k), or clot formation time, alpha angle (alpha), and maximal amplitude (MA)] were recorded before and after the administration of a bolus of 80 microg/kg rFVIIa. These patients were compared with six controls who did not receive rFVIIa. In contrast with the control group, a significant shortening of PT (P = 0.028) and aPTT (P = 0.028), r (P = 0.046) and k (P = 0.043) values, and a significant incline of the alpha angle (P = 0.028) were noticed after injection of rFVIIa, whereas MA increased not significantly (P = 0.075). rFVIIa rapidly improved coagulation variables in liver transplant patients including PT and aPTT. Of the TEG variables, r, k and alpha angle significantly improved, and MA showed a trend to increase. These data suggest that rFVIIa not only influences the speed of clot formation, but also the physical properties of the clot, which cannot be detected by routine coagulation tests.

Laboratory diagnosis of dysfibrinogenemia

Dysfibrinogenemia is a coagulation disorder caused by a variety of structural abnormalities in the fibrinogen molecule that result in abnormal fibrinogen function. It can be inherited or acquired. The inherited form is associated with increased risk of bleeding, thrombosis, or both in the same patient or family. Traditionally, dysfibrinogenemia is diagnosed by abnormal tests of fibrin clot formation; the thrombin time and reptilase time are the screening tests, and the fibrinogen clotting activity-antigen ratio is the confirmatory test. The inherited form is diagnosed by demonstrating similar laboratory test abnormalities in family members, and if necessary by analysis of the fibrinogen protein or fibrinogen genes in the patient. The acquired form is diagnosed by demonstrating abnormal liver function tests and by ruling out dysfibrinogenemia in family members. This article reviews the laboratory testing of dysfibrinogenemia and presents an algorithm for sequential test selection that can be used for diagnosis.

Acquired factor VII deficiency in hematopoietic stem cell transplant recipients

Acquired factor VII (FVII) deficiency in the absence of vitamin K deficiency, oral anticoagulant therapy, synthetic liver dysfunction, or DIC is rare, with only a handful of cases thus far reported. In the period from 1990 to 1996 we identified eight patients with acquired FVII deficiency, all of whom presented with prolongation of the prothrombin time (PT) in the first 2 weeks following stem cell transplantation (SCT). The mean plasma FVII clotting activity (FVII:c) was 22% (range 8-35%) with an approximately equivalent reduction in FVII antigen (FVII:Ag) level. Mean plasma levels of fibrinogen and factors II, V, IX, and X were normal. Protein C activity was significantly depressed in only one of the three patients in whom it was measured. Several patients experienced bleeding complications, and hemorrhage directly accounted for death in two cases. Veno-occlusive disease of the liver developed in three patients. We conclude that FVII deficiency should be considered in the differential diagnosis of prolonged PT in patients who have recently undergone SCT. The mechanism of this acquired deficiency state remains to be defined.

Recombinant factor VIIa improves clot formation but not fibrolytic potential in patients with cirrhosis and during liver transplantation

Cirrhosis is associated with a bleeding tendency, which is particularly pronounced during orthotopic liver transplantation (OLT). A novel approach to treating the bleeding diathesis of patients with cirrhosis is administration of recombinant factor VIIa (rFVIIa). This study examined whether the efficacy of rFVIIa in cirrhosis might be explained in part by enhanced down-regulation of fibrinolysis by thrombin-activatable fibrinolysis inhibitor (TAFI). Addition of therapeutic or supratherapeutic doses of rFVIIa to plasma of 12 patients with stable cirrhosis did not result in a prolongation of clot lysis time, though clotting times were significantly reduced. Also, clot lysis assays of plasma samples taken during and after OLT, which was performed with or without a single bolus dose of rFVIIa, did not show any effect of rFVIIa on plasma fibrinolytic potential. In conclusion, this study shows no evidence for an antifibrinolytic effect of rFVIIa in cirrhotic patients or in patients undergoing OLT.

The significance of heparin-coated veno-venous bypass circuits in liver transplantation

We studied the effects of veno-venous bypass (VVBP) circuit surface heparinization on the activation of the plasma defence systems (coagulation, fibrinolysis, kallikrein-kinin and complement) and leukocyte activation in a prospective randomized study in 20 patients during and 1 day after liver transplantation (OLT). To our knowledge, this is the first study of this kind where the possible benefits of surface heparinization of the VVBP circuit in OLT have been investigated. Twenty patients were randomized to either heparin-coated (HC) VVBP equipment or to otherwise identical noncoated (NC) circuits. Five blood samples were drawn during the OLT procedure: one just before VVBP, three during VVBP and one 5 min after portal venous reperfusion (PVR). A further sample was taken 1 day after the operation. Components of the blood coagulation, fibrinolytic and kallikrein-kinin systems were analysed using functional assays (chromogenic peptide substrate assays) or enzyme immunoassays (EIA). Complement system factors and granulocyte activation, represented by myeloperoxidase (MPO) release, were analyzed by EIA. Activation of the plasma defence systems occurred in both groups at an early stage during OLT and a further activation occurred 5 min after PVR. MPO levels were slightly elevated 5 min after PVR. However, no significant differences between the two groups were observed. Significant activation of the humoral defense systems was found in both groups during OLT. A considerably larger study, including at least 330 patients, is necessary to fully assess the possible benefits of surface heparinization of the VVBP circuit.

Expression of factor VII in the liver of patients with liver disease: correlations with the disease severity and impairment in the hemostasis

Factor VII (FVII) plasma levels in patients with liver disease may be below the normal range. However, no data are available on FVII expression in liver biopsies from patients with liver diseases other than cirrhosis. We have analyzed the expression of FVII by in situ hybridization in liver biopsies from 50 patients in comparison with the procoagulant activity of FVII, and with the plasma levels as activated FVII (FVIIa) and FVII antigen. The level of FVIIa was significantly lower in stage 4 liver fibrosis patients than in the remaining ones (P < 0.05). The percentage of hepatocytes expressing FVII was significantly lower in stage 4 liver fibrosis patients (4.1+/-1.3%) than in stage 3 (22.7+/-6.1%), stage 2 (31.5+/-6.1%), stage 1 (43.7+/-8.2%) and stage 0 patients (63.8+/-4.4%) (P < 0.001). These percentages correlated inversely in a statistically significant way with the histological activity index and the liver function tests. We have demonstrated that the FVIIa plasma levels in patients with chronic liver disease other than cirrhosis may be below the normal range in the absence of blood coagulation impairment. The percentage of hepatocytes expressing FVII decreases as the severity of liver damage increases.