Effect of therapeutic paracentesis on plasma volume and transvascular escape rate of albumin in patients with cirrhosis

Liver kidney crosstalk: Hepatorenal syndrome

The dying liver causes the suffocation of the kidneys, which is a simplified way of describing the pathophysiology of hepatorenal syndrome (HRS). HRS is characterized by reversible functional renal impairment due to reduced blood supply and glomerular filtration rate, secondary to increased vasodilators. Over the years, HRS has gained much attention and focus among hepatologists and nephrologists. HRS is a diagnosis of exclusion, and in some cases, it carries a poor prognosis. Different classifications have emerged to better understand, diagnose, and promptly treat this condition. This targeted review aims to provide substantial insight into the epidemiology, pathophysiology, diagnosis, and management of HRS, shed light on the various milestones of this condition, and add to our current understanding.

Role of Terlipressin in Cirrhotic Patients with Ascites and without Hepatorenal Syndrome: A Systematic Review of Current Evidence

Ascites, a common complication in cirrhosis, is prone to the development of acute kidney injury or hepatorenal syndrome and can be complicated by circulatory dysfunction after paracentesis. Terlipressin has not been considered as the mainstay treatment option for ascites in cirrhosis yet. The present work aimed to systematically review the current evidence regarding the use of terlipressin in cirrhosis with ascites and without hepatorenal syndrome. PubMed, EMBASE, and Cochrane Library databases were searched for relevant studies. Twelve studies were eligible. In 3 studies (1 randomized controlled trial and 2 single-arm studies without controls) involving 32 patients who received terlipressin for nonrefractory ascites, terlipressin improved hemodynamics by decreasing the heart rate and cardiac output and increasing the mean arterial pressure and systemic vascular resistance. In 5 studies (1 randomized controlled trial, 2 single-arm studies without controls, and 2 comparative studies with controls) involving 67 patients who received terlipressin for refractory ascites, terlipressin improved renal function by increasing the glomerular filtration rate, renal blood flow, urinary sodium, and urine output and decreasing serum creatinine. In 4 studies (4 randomized controlled trials) involving 71 patients who received terlipressin for preventing from paracentesis-induced circulatory dysfunction, terlipressin prevented from paracentesis-induced circulatory dysfunction by increasing the mean arterial pressure and systemic vascular resistance and decreasing plasma renin. Terlipressin may improve hemodynamics, severity of ascites, and renal function and prevent from paracentesis-induced circulatory dysfunction in cirrhosis with ascites and without hepatorenal syndrome. However, no study has evaluated the effect of terlipressin for prevention of acute kidney injury.

Plasma expanders for people with cirrhosis and large ascites treated with abdominal paracentesis

BACKGROUND

Plasma volume expanders are used in connection to paracentesis in people with cirrhosis to prevent reduction of effective plasma volume, which may trigger deleterious effect on haemodynamic balance, and increase morbidity and mortality. Albumin is considered the standard product against which no plasma expansion or other plasma expanders, e.g. other colloids (polygeline , dextrans, hydroxyethyl starch solutions, fresh frozen plasma), intravenous infusion of ascitic fluid, crystalloids, or mannitol have been compared. However, the benefits and harms of these plasma expanders are not fully clear.

OBJECTIVES

To assess the benefits and harms of any plasma volume expanders such as albumin, other colloids (polygeline, dextrans, hydroxyethyl starch solutions, fresh frozen plasma), intravenous infusion of ascitic fluid, crystalloids, or mannitol versus no plasma volume expander or versus another plasma volume expander for paracentesis in people with cirrhosis and large ascites.

SEARCH METHODS

We searched the Cochrane Hepato-Biliary Group Controlled Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, LILACS, CNKI, VIP, Wanfang, Science Citation Index Expanded, and Conference Proceedings Citation Index until January 2019. Furthermore, we searched FDA, EMA, WHO (last search January 2019), www.clinicaltrials.gov/, and www.controlled-trials.com/ for ongoing trials.

SELECTION CRITERIA

Randomised clinical trials, no matter their design or year of publication, publication status, and language, assessing the use of any type of plasma expander versus placebo, no intervention, or a different plasma expander in connection with paracentesis for ascites in people with cirrhosis. We considered quasi-randomised, retrieved with the searches for randomised clinical trials only, for reports on harms.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. We calculated the risk ratio (RR) or mean difference (MD) using the fixed-effect model and the random-effects model meta-analyses, based on the intention-to-treat principle, whenever possible. If the fixed-effect and random-effects models showed different results, then we made our conclusions based on the analysis with the highest P value (the more conservative result). We assessed risks of bias of the individual trials using predefined bias risk domains. We assessed the certainty of the evidence at an outcome level, using GRADE, and constructed 'Summary of Findings' tables for seven of our review outcomes.

MAIN RESULTS

We identified 27 randomised clinical trials for inclusion in this review (24 published as full-text articles and 3 as abstracts). Five of the trials, with 271 participants, assessed plasma expanders (albumin in four trials and ascitic fluid in one trial) versus no plasma expander. The remaining 22 trials, with 1321 participants, assessed one type of plasma expander, i.e. dextran, hydroxyethyl starch, polygeline, intravenous infusion of ascitic fluid, crystalloids, or mannitol versus another type of plasma expander, i.e. albumin in 20 of these trials and polygeline in one trial. Twenty-five trials provided data for quantitative meta-analysis. According to the Child-Pugh classification, most participants were at an intermediate to advanced stage of liver disease in the absence of hepatocellular carcinoma, recent gastrointestinal bleeding, infections, and hepatic encephalopathy. All trials were assessed as at overall high risk of bias. Ten trials seemed not to have been funded by industry; twelve trials were considered unclear about funding; and five trials were considered funded by industry or a for-profit institution.We found no evidence of a difference in effect between plasma expansion versus no plasma expansion on mortality (RR 0.52, 95% CI 0.06 to 4.83; 248 participants; 4 trials; very low certainty); renal impairment (RR 0.32, 95% CI 0.02 to 5.88; 181 participants; 4 trials; very low certainty); other liver-related complications (RR 1.61, 95% CI 0.79 to 3.27; 248 participants; 4 trials; very low certainty); and non-serious adverse events (RR 1.04, 95% CI 0.32 to 3.40; 158 participants; 3 trials; very low certainty). Two of the trials stated that no serious adverse events occurred while the remaining trials did not report on this outcome. No trial reported data on health-related quality of life.We found no evidence of a difference in effect between experimental plasma expanders versus albumin on mortality (RR 1.03, 95% CI 0.82 to 1.30; 1014 participants; 14 trials; very low certainty); serious adverse events (RR 0.89, 95% CI 0.10 to 8.30; 118 participants; 2 trials; very low certainty); renal impairment (RR 1.17, 95% CI 0.71 to 1.91; 1107 participants; 17 trials; very low certainty); other liver-related complications (RR 1.10, 95% CI 0.82 to 1.48; 1083 participants; 16 trials; very low certainty); and non-serious adverse events (RR 1.37, 95% CI 0.66 to 2.85; 977 participants; 14 trials; very low certainty). We found no data on heath-related quality of life and refractory ascites.

AUTHORS' CONCLUSIONS

Our systematic review and meta-analysis did not find any benefits or harms of plasma expanders versus no plasma expander or of one plasma expander such as polygeline, dextrans, hydroxyethyl starch, intravenous infusion of ascitic fluid, crystalloids, or mannitol versus albumin on primary or secondary outcomes. The data originated from few, small, mostly short-term trials at high risks of systematic errors (bias) and high risks of random errors (play of chance). GRADE assessments concluded that the evidence was of very low certainty. Therefore, we can neither demonstrate or discard any benefit of plasma expansion versus no plasma expansion, and differences between one plasma expander versus another plasma expander.Larger trials at low risks of bias are needed to assess the role of plasma expanders in connection with paracentesis. Such trials should be conducted according to the SPIRIT guidelines and reported according to the CONSORT guidelines.

Approach and management of dysnatremias in cirrhosis

Hypervolemic (dilutional) hyponatremia is the most common dysnatremia in cirrhosis, with a prevalence close to 50% in patients with ascites, while hypovolemic hyponatremia occurs in a minority of cases. Hyponatremia carries a poor prognosis, being associated with increased mortality and reduced survival after liver transplantation. Hypernatremia is rarer and is also associated with an adverse prognosis. Increased non-osmotic secretion of arginine vasopressin and altered renal tubular sodium handling due to impaired free water generation are the mechanisms leading to hypervolemic hyponatremia, while diuretic-induced fluid loss is the main cause of hypovolemic hyponatremia. Hypernatremia usually follows hypotonic fluid losses due to osmotic diuresis (glycosuria) or lactulose-induced diarrhea. The main clinical manifestations of dysnatremias are due to their effects on the central nervous system: astroglial cell hyperhydration follows hyponatremia-an abnormality that exacerbates ammonia neurotoxicity-while the opposite abnormality occurs with hypernatremia. Asymptomatic or mildly symptomatic hypervolemic hyponatremia is mainly managed by correcting of precipitating factors and non-osmotic fluid restriction. Severe, life-threatening hyponatremia requires hypertonic saline infusion, avoiding rapid and complete correction of serum sodium concentration to prevent neurological sequelae such as osmotic demyelination. V₂ receptor blockade by vaptans may be considered in patients with sustained hyponatremia waitlisted for liver transplantation. Diuretic withdrawal and plasma volume expansion are required in hypovolemic hypernatremia. Prompt recognition, removal of the precipitating factor(s) and non-osmotic fluid administration represent the mainstays of hypernatremia management. Rapid correction of long-standing hypernatremia can lead to cerebral edema and has to be avoided.

New Insights About Albumin and Liver Disease

Decompensated liver cirrhosis has a dismal prognosis, with an overall survival of 2-4 years, which is worse than for many oncological diseases. Albumin is an important tool in the management of patients with cirrhosis, since it decreases for less than half the risk for post-paracentesis cardiocirculatory dysfunction and mortality associated with spontaneous bacterial infection, as well as, it triplicates the response to terlipressin in patients with hepatorenal syndrome. Recently, research on albumin has been a hot topic, with important new insights such as the characterization of the pleiotropic effects of albumin (which surpass its oncotic properties) and the concept of effective albumin concentration. In fact, patients with liver cirrhosis present posttranslational modifications on albumin that compromises its function. Those modified albumin forms were proved to have prognostic value and its knowledge may change the paradigm of albumin treatment. In this review, we critically summarize the latest evidence on the potential benefits of albumin in patients with end-stage liver disease.

Abdominal Circulatory Interactions

The abdominal compartment is separated from the thoracic compartment by the diaphragm. Under normal circumstances, a large portion of the venous return crosses the splanchnic and nonsplanchnic abdominal regions before entering the thorax and the right side of the heart. Mechanical ventilation may affect abdominal venous return independent of its interactions at the thoracic level. Changes in pressure in the intra-abdominal compartment may have important implications for organ function within the thorax, particularly if there is a sustained rise in intra-abdominal pressure. It is important to understand the consequences of abdominal pressure changes on respiratory and circulatory physiology. This article elucidates important abdominal-respiratory-circulatory interactions and their clinical effects.

Role of albumin in diseases associated with severe systemic inflammation: Pathophysiologic and clinical evidence in sepsis and in decompensated cirrhosis

The metabolism of albumin in inflammatory states such as sepsis or major surgery is complex and still not well characterized. Nevertheless, in inflammatory states, albumin synthesis has been observed to increase. By contrast, in decompensated cirrhosis, a disease characterized by systemic inflammation, albumin synthesis by the liver may decrease to 30% to 50% of normal values. Furthermore, in these conditions, there are high capillary leakage and altered albumin kinetics. The discussion regarding the effect of exogenous albumin administration on intravascular volume in inflammatory states should therefore address albumin turnover. To add complexity to our understanding of the effects of albumin, there are many data indicating that the therapeutic action of albumin is mediated not only through the impact on plasma volume expansion but also through a modulatory effect on inflammation and oxidative stress. All these characteristics are relevant to diseases associated with systemic inflammation including sepsis and decompensated cirrhosis.

Albumin in chronic liver disease: structure, functions and therapeutic implications

Human serum albumin is a critical plasma protein produced by the liver with a number of accepted clinical indications in chronic liver disease including management of circulatory and renal dysfunction in patients with ascites. Advanced cirrhosis is characterised by reduced albumin concentration as well as impaired albumin function as a result of specific structural changes and oxidative damage. Traditionally, the biologic and therapeutic role of albumin in liver disease was attributed to its oncotic effects but it is now understood that albumin has a wide range of other important physiologic functions such as immunomodulation, endothelial stabilisation, antioxidant effects and binding multiple drugs, toxins and other molecules. This review discusses the multifunctional properties of albumin and, in particular, the biologic and clinical implications of structural and functional changes of albumin that are associated with cirrhosis. Based on these insights, we explore the current and potential future therapeutic uses of albumin in liver disease.

Hyponatremia in Patients with Cirrhosis of the Liver

Hyponatremia is common in cirrhosis. It mostly occurs in an advanced stage of the disease and is associated with complications and increased mortality. Either hypovolemic or, more commonly, hypervolemic hyponatremia can be seen in cirrhosis. Impaired renal sodium handling due to renal hypoperfusion and increased arginine-vasopressin secretion secondary to reduced effective volemia due to peripheral arterial vasodilation represent the main mechanisms leading to dilutional hyponatremia in this setting. Patients with cirrhosis usually develop slowly progressing hyponatremia. In different clinical contexts, it is associated with neurological manifestations due to increased brain water content, where the intensity is often magnified by concomitant hyperammonemia leading to hepatic encephalopathy. Severe hyponatremia requiring hypertonic saline infusion is rare in cirrhosis. The management of asymptomatic or mildly symptomatic hyponatremia mainly rely on the identification and treatment of precipitating factors. However, sustained resolution of hyponatremia is often difficult to achieve. V2 receptor blockade by Vaptans is certainly effective, but their long-term safety, especially when associated to diuretics given to control ascites, has not been established as yet. As in other conditions, a rapid correction of long-standing hyponatremia can lead to irreversible brain damage. The liver transplant setting represents a condition at high risk for the occurrence of such complications.

Acute kidney injury in schistosomiasis: a retrospective cohort of 60 patients in Brazil

The aim of this study is to investigate renal involvement in schistosomiasis. This is a retrospective cohort of 60 consecutive patients with schistosomiasis admitted to a university hospital in Maceió, Brazil. The patients were divided into 2 groups: patients with and without acute kidney injury (AKI) according to the RIFLE criteria. We compared the groups for differences in clinical manifestations and laboratory tests. Patients' mean age was 58 ± 16 yr, and 56.7% were female. The average length of hospital stay was 16.4 ± 12.1 days. Patients with hypertension and diabetes were 35% and 21.7% respectively. The main clinical symptoms and signs presented were ascites (86.7%), splenomegaly (80%), and hepatomegaly (63.3%). Current or previous history of upper gastrointestinal bleeding was found in 45% of patients, esophageal varices on endoscopy were present in 92%, and periportal fibrosis on ultrasound examination in 81% of patients. AKI incidence was 43.3% during hospital stay. Mean age and length of hospitalization were higher in the AKI group. Diuretic use, such as furosemide and spironolactone, ascites, and AST levels were also associated with AKI. Death occurred in 5 cases (8.5%), 4 of them in the AKI group. The classifications Child-Pugh score (CHILD) and Model for End-Stage Liver Disease (MELD), used to assess the severity and prognosis of chronic liver disease, presented higher scores among patients with AKI (CHILD: 9.5 ± 1.5 vs. 8.4 ± 1.7, P = 0.02; MELD: 19 ± 5.8 vs. 13 ± 3.9, P < 0.001). Renal dysfunction is an important feature of schistosomiasis, which is associated with significant morbidity and possible increased mortality. Further studies are necessary to establish the mechanisms through which schistosomiasis can lead to renal dysfunction.

Paracentesis-induced circulatory dysfunction: a primer for the interventional radiologist

Paracentesis-induced circulatory dysfunction is a complication of large volume paracentesis that leads to faster reaccumulation of ascites, hyponatremia, renal impairment, and shorter survival. Knowledge of the pathophysiology, clinical presentation, diagnosis, and prevention of this condition is vital to the interventional radiologist as a valued team member in the treatment of ascites.

Human serum albumin, systemic inflammation, and cirrhosis

Human serum albumin (HSA) is one of the most frequent treatments in patients with decompensated cirrhosis. Prevention of paracentesis-induced circulatory dysfunction, prevention of type-1 HRS associated with bacterial infections, and treatment of type-1 hepatorenal syndrome are the main indications. In these indications treatment with HSA is associated with improvement in survival. Albumin is a stable and very flexible molecule with a heart shape, 585 residues, and three domains of similar size, each one containing two sub-domains. Many of the physiological functions of HSA rely on its ability to bind an extremely wide range of endogenous and exogenous ligands, to increase their solubility in plasma, to transport them to specific tissues and organs, or to dispose of them when they are toxic. The chemical structure of albumin can be altered by some specific processes (oxidation, glycation) leading to rapid clearance and catabolism. An outstanding feature of HSA is its capacity to bind lipopolysaccharide and other bacterial products (lipoteichoic acid and peptidoglycan), reactive oxygen species, nitric oxide and other nitrogen reactive species, and prostaglandins. Binding to NO and prostaglandins are reversible, so they can be transferred to other molecules at different sites from their synthesis. Through these functions, HSA modulates the inflammatory reaction. Decompensated cirrhosis is a disease associated systemic inflammation, which plays an important role in the pathogenesis of organ or system dysfunction/failure. Although, the beneficial effects of HAS have been traditionally attributed to plasma volume expansion, they could also relate to its effects modulating systemic and organ inflammation.

NT-proBNP Changes in Patients with Ascites during Large Volume Paracentesis

Background. N-terminal probrain natriuretic peptide (NT-proBNP) is a hormone involved in the regulation of cardiovascular homeostasis. Changes in serum NT-proBNP during large volume paracentesis (LVP) in patients with ascites have never before been examined. Aims. To determine if significant changes in serum NT-proBNP occur in patients undergoing LVP and the associated clinical correlates in patients with cirrhosis. Method. A total of 45 patients with ascites were prospectively recruited. Serum NT-proBNP, biochemistry, and haemodynamics were determined at baseline and at key time points during and after paracentesis. Results. 34 patients were analysed; 19 had ascites due to cirrhosis and 15 from malignancy. In those with cirrhosis, NT-proBNP decreased by 77.3 pg/mL at 2 L of drainage and 94.3 pg/mL at the end of paracentesis, compared with an increase of 10.5 pg/mL and 77.2 pg/mL in cancer patients at the same time points (P = 0.05 and P = 0.03). Only congestive cardiac failure (CCF) was an independent predictor of significant NT-proBNP changes at the end of drainage in cirrhotic patients (P < 0.01). There were no significant changes in haemodynamics or renal biochemistry for either group. Conclusion. Significant reductions in serum NT-proBNP during LVP occur in patients with cirrhosis but not malignancy, and only comorbid CCF appeared to predict such changes.

Kidneys in chronic liver diseases

Acute kidney injury (AKI), defined as an abrupt increase in the serum creatinine level by at least 0.3 mg/dL, occurs in about 20% of patients hospitalized for decompensating liver cirrhosis. Patients with cirrhosis are susceptible to developing AKI because of the progressive vasodilatory state, reduced effective blood volume and stimulation of vasoconstrictor hormones. The most common causes of AKI in cirrhosis are pre-renal azotemia, hepatorenal syndrome and acute tubular necrosis. Differential diagnosis is based on analysis of circumstances of AKI development, natriuresis, urine osmolality, response to withdrawal of diuretics and volume repletion, and rarely on renal biopsy. Chronic glomerulonephritis and obstructive uropathy are rare causes of azotemia in cirrhotic patients. AKI is one of the last events in the natural history of chronic liver disease, therefore, such patients should have an expedited referral for liver transplantation. Hepatorenal syndrome (HRS) is initiated by progressive portal hypertension, and may be prematurely triggered by bacterial infections, nonbacterial systemic inflammatory reactions, excessive diuresis, gastrointestinal hemorrhage, diarrhea or nephrotoxic agents. Each type of renal disease has a specific treatment approach ranging from repletion of the vascular system to renal replacement therapy. The treatment of choice in type 1 hepatorenal syndrome is a combination of vasoconstrictor with albumin infusion, which is effective in about 50% of patients. The second-line treatment of HRS involves a transjugular intrahepatic portosystemic shunt, renal vasoprotection or systems of artificial liver support.

Albumin infusion in patients undergoing large-volume paracentesis: a meta-analysis of randomized trials

Albumin infusion reduces the incidence of postparacentesis circulatory dysfunction among patients with cirrhosis and tense ascites, as compared with no treatment. Treatment alternatives to albumin, such as artificial colloids and vasoconstrictors, have been widely investigated. The aim of this meta-analysis was to determine whether morbidity and mortality differ between patients receiving albumin versus alternative treatments. The meta-analysis included randomized trials evaluating albumin infusion in patients with tense ascites. Primary endpoints were postparacentesis circulatory dysfunction, hyponatremia, and mortality. Eligible trials were sought by multiple methods, including computer searches of bibliographic and abstract databases and the Cochrane Library. Results were quantitatively combined under a fixed-effects model. Seventeen trials with 1,225 total patients were included. There was no evidence of heterogeneity or publication bias. Compared with alternative treatments, albumin reduced the incidence of postparacentesis circulatory dysfunction (odds ratio [OR], 0.39; 95% confidence interval [CI], 0.27-0.55). Significant reductions in that complication by albumin were also shown in subgroup analyses versus each of the other volume expanders tested (e.g., dextran, gelatin, hydroxyethyl starch, and hypertonic saline). The occurrence of hyponatremia was also decreased by albumin, compared with alternative treatments (OR, 0.58; 95% CI, 0.39-0.87). In addition, mortality was lower in patients receiving albumin than alternative treatments (OR, 0.64; 95% CI, 0.41-0.98).

CONCLUSIONS

This meta-analysis provides evidence that albumin reduces morbidity and mortality among patients with tense ascites undergoing large-volume paracentesis, as compared with alternative treatments investigated thus far.

Critical care management of patients with end-stage liver disease

OBJECTIVES

To review the management of complications related to end-stage liver disease in the intensive care unit. The goal of this review is to address topics important to the practicing physician.

DATA SOURCES

We performed an organ system-based PubMed literature review focusing on the diagnosis and treatment of critical complications of end-stage liver disease. DATA SYNTHESIS AND FINDINGS: When available, preferential consideration was given to randomized controlled trials. In the absence of trials, observational and retrospective studies and consensus opinions were included. We present our recommendations for the neurologic, cardiovascular, pulmonary, gastrointestinal, renal, and infectious complications of end-stage liver disease.

CONCLUSIONS

Complications related to end-stage liver disease have significant morbidity and mortality. Management of these complications in the intensive care unit requires awareness and expertise among physicians from a wide variety of fields.

Diagnosis and therapy of ascites in liver cirrhosis

Ascites is one of the major complications of liver cirrhosis and is associated with a poor prognosis. It is important to distinguish noncirrhotic from cirrhotic causes of ascites to guide therapy in patients with noncirrhotic ascites. Mild to moderate ascites is treated by salt restriction and diuretic therapy. The diuretic of choice is spironolactone. A combination treatment with furosemide might be necessary in patients who do not respond to spironolactone alone. Tense ascites is treated by paracentesis, followed by albumin infusion and diuretic therapy. Treatment options for refractory ascites include repeated paracentesis and transjugular intrahepatic portosystemic shunt placement in patients with a preserved liver function. Potential complications of ascites are spontaneous bacterial peritonitis (SBP) and hepatorenal syndrome (HRS). SBP is diagnosed by an ascitic neutrophil count > 250 cells/mm³ and is treated with antibiotics. Patients who survive a first episode of SBP or with a low protein concentration in the ascitic fluid require an antibiotic prophylaxis. The prognosis of untreated HRS type 1 is grave. Treatment consists of a combination of terlipressin and albumin. Hemodialysis might serve in selected patients as a bridging therapy to liver transplantation. Liver transplantation should be considered in all patients with ascites and liver cirrhosis.

[Ascites, hepatorenal syndrome and spontaneous bacterial peritonitis in patients with portal hypertension]

Ascites, hepatic encephalopathy and variceal hemorrhage are three major complications of portal hypertension. The diagnostic evaluation of ascites involves an assessment of its etiology by determining the serum-ascites albumin gradient and the exclusion of spontaneous bacterial peritonitis. Ascites is primarily related to an inability to excrete an adequate amount of sodium into urine, leading to a positive sodium balance. Sodium restriction and diuretic therapy are keys of ascites control. But, with the case of refractory ascites, large volume paracentesis and transjugular portosystemic shunts are required. In hepatorenal syndrome, splanchnic vasodilatation with reduction in effective arterial volume causes intense renal vasoconstriction. Splanchnic and/or peripheral vasoconstrictors with albumin infusion, and renal replacement therapy are only bridging therapy. Liver transplantation is the only definitive modality of improving the long term prognosis.

Evaluation and management of patients with refractory ascites

Some patients with ascites due to liver cirrhosis become no longer responsive to diuretics. Once other causes of ascites such as portal vein thrombosis, malignancy or infection and non-compliance with medications and low sodium diet have been excluded, the diagnosis of refractory ascites can be made based on strict criteria. Patients with refractory ascites have very poor prognosis and therefore referral for consideration for liver transplantation should be initiated. Search for reversible components of the underlying liver pathology should be undertaken and targeted therapy, when available, should be considered. Currently, serial large volume paracentesis (LVP) and transjugular intrahepatic portasystemic stent-shunt (TIPS) are the two mainstay treatment options for refractory ascites. Other treatment options are available but not widely used either because they carry high morbidity and mortality (most surgical options) rates, or are new interventions that have shown promise but still need further evaluation. In this comprehensive review, we describe the evaluation and management of patients with refractory ascites from the prospective of the practicing physician.

Renal dysfunction in liver cirrhosis

Liver cirrhosis is an escalating health problem attributed to numerous causes, including an increase in alcohol consumption, morbid obesity and chronic viral hepatitis. The circulatory disturbances seen in advanced cirrhosis lead to the development of ascites, which often lead to progressive renal impairment or the development of hepatorenal syndrome. Furthermore, cirrhotic patients commonly experience clinical situations that predispose them to the development of pre-renal failure, such as dehydration, hypovolaemia, septic shock, or exposure to nephrotoxic drugs. This article provides an overview of the main causes of acute renal failure in liver cirrhosis and describes the current medical and nursing management.

Systemic hemodynamics, vasoactive systems, and plasma volume in patients with severe Budd-Chiari syndrome

Budd-Chiari syndrome (BCS) causes postsinusoidal portal hypertension, which leads to complications similar to those observed in cirrhosis. However, no studies have investigated whether patients with BCS develop the hyperdynamic circulatory syndrome present in patients with cirrhosis who have portal hypertension. We evaluated systemic and cardiopulmonary hemodynamics, plasma renin activity, aldosterone and norepinephrine levels, and plasma volume in patients with BCS admitted for complications of portal hypertension. BCS patients had mean systemic and cardiopulmonary pressures and cardiac indices that were within the normal range but were significantly different from those of a group of patients with cirrhosis matched by sex, body surface, and liver function (cardiac index 3.1 +/- 0.7 vs. 4.9 +/- 1.2 L.min(-1).m(-2); P < .001; systemic vascular resistance [SVR] index, 2,189 +/- 736 vs. 1,377 +/- 422 dyne.s.cm(-5).m(-2), P < .001). Despite normal systemic vascular resistance, BCS patients had activation of the neurohumoral vasoactive systems, as evidenced by increased plasma renin activity, aldosterone and norepinephrine levels (15.0 +/- 21.5 ng/mL . h, 76.7 +/- 106.8 ng/dL, 586 +/- 868 pg/mL; respectively) and plasma volume expansion. The analysis of individual BCS patients identified that 7 of the 21 patients actually had reduced SVR index. These patients had the greatest plasma volume expansion. A significant inverse correlation between plasma volume and SVR index was observed. In conclusion, patients with BCS had activation of vasoactive neurohumoral systems and expanded plasma volume. This outcome was observed even though most of these patients did not exhibit systemic vasodilation and cardiac output was not increased, in marked contrast with what is observed in patients with cirrhosis.

Le syndrome hépatorénal chez le patient cirrhotique

Hepatorenal syndrome is a particular form of functional renal failure which may develop in patients with liver cirrhosis. On a clinical standpoint, precise diagnostic criteria have been established to clearly define this entity, whereas recent advances in the understanding of the biology of vasoactive mediators and the physiology of microcirculation have allowed to better anticipate its pathophysiological mechanisms. During the course of cirrhosis, sinusoidal portal hypertension leads to splanchnic and systemic vasodilation, responsible for a reduction of effective arterial blood volume. As a result, a state of intense renal vasoconstriction develops, leading to renal failure in the absence of any organic renal disease. At this stage, liver transplantation is the only definitive therapy able to reverse renal dysfunction. In recent years, innovative therapies have shown promise to prolong survival in patients with hepatorenal syndrome, including the administration of analogs of vasopressin (mainly terlipressin), the insertion of transjugular intrahepatic portosystemic shunts and the use of novel techniques of dialysis. On a preventive viewpoint, several simple measures have been shown to reduce the risk of hepatorenal syndrome in cirrhotic patients, including the appropriate use of diuretics, the avoidance of nephrotoxic drugs, the prophylaxis of spontaneous bacterial peritonitis and optimal fluid management in patients undergoing large volume paracentesis.

Volume adaptation in chronic liver disease: on the static and dynamic location of water, salt, protein and red cells in cirrhosis

Adequate size and distribution of the circulating medium are important for cardiovascular function, tissue oxygenation and fluid homoeostasis. Patients with cirrhosis have an abnormal distribution of increased blood volume, increased total vascular compliance and increased arterial compliance. The pattern and temporal relations of plasma and blood volume expansion are important for pathophysiological, diagnostic and therapeutic purposes and depend highly on the type of load (water, saline, oncotic material, red blood cells). In some aspects patients with cirrhosis respond differently from healthy subjects. Thus the reaction during volume expansion may be somewhat blunted, and in advanced cirrhosis, the non-central parts of the circulation in particular, including the splanchnic blood volume, are expanded by a volume load. The use of vasoactive drugs has provided important information on the changes in haemodynamic and homoeostatic mechanisms in patients with cirrhosis. Infusion of oncotic material (preferably albumin) may prevent circulatory dysfunction during certain types of stress. Volume expansion in advanced cirrhosis is qualitatively and quantitively different from that of healthy subjects and those with early cirrhosis. Timely volume handling is essential, but difficult as it is a balance between hypovolaemia and excess extravascular volume loading with further circulatory dysfunction in these patients with a hyperdynamic, but hyporeactive circulation.

Hyponatremia in liver cirrhosis: pathophysiological principles of management

Hyponatremia is common in cirrhosis, where it impairs encephalopathy. It could be either due to excess water, or reduced Na, or a combination of both. The diagnosis can be established with clinical skills aided by simple data like weight, blood pressure and plasma electrolytes. The quantitative estimates of the water surfeit or solute deficit, easily performed with simple formulas and measurements, guide accurate and programmed treatment procedures, avoiding the occurrence of the ominous central pontine myelinolysis.

Plasma volume expansion by albumin in cirrhosis. Relation to blood volume distribution, arterial compliance and severity of disease

BACKGROUND/AIMS

The aim of the study was to investigate the effect of a standard albumin load on blood volume distribution, arterial compliance, and the renin-angiotensin-aldosterone system in patients with different degrees of cirrhosis.

METHODS

31 patients with cirrhosis (Child classes A/B/C=8/14/9) received an intravenous infusion of 40 g human serum albumin during a haemodynamic investigation.

RESULTS

Whereas plasma- and blood volume increased by 23 and 15%, respectively (P<0.001), a significant increase in central blood volume was found only in class A patients (+8%, P<0.05), but not in class B or class C patients (+2.7%, not significant (n.s.)). In contrast, arterial compliance only increased significantly in class C patients (+18%, P<0.05), but not in class A or class B patients (+6%, n.s.). Plasma renin activity (PRA) decreased significantly in class C patients (-31%, P<0.05). When all patients were compared, the change in arterial compliance was inversely correlated to the change in PRA (r=-0.50, P<0.01).

CONCLUSIONS

Although infusion of albumin does not expand the central blood volume in patients with advanced cirrhosis, the results indicate a significant improvement in the low effective arterial blood volume of such patients, which may be important in the prevention of circulatory dysfunction.

Erythropoiesis regulation during the development of ascites syndrome in broiler chickens: a possible role of corticosterone

The ascites syndrome in broiler chickens is attributed to metabolic burdening, which results from intensive genetic selection for rapid growth coupled with exposure to extreme environmental conditions, such as low ambient temperature. These conditions impose on the broilers difficulties in fulfilling tissue demands for oxygen, and the birds exhibit a decrease in blood oxygen saturation and high hematocrit values. It is unknown whether the increase in hematocrit results from alteration in erythropoiesis or from fluid exudation out of the blood system to the abdominal cavity. The present study was conducted to examine the association between abnormal stress response and erythropoiesis process in ascitic broilers. Ascitic chickens revealed a uniquely continuous stress response: expressing an increase (P < or = 0.05) in plasma corticosterone concentration 2 to 3 wk before death. At 5 wk of age, ascitic broilers exhibited an increase (P < 0.05) in hematocrit, blood cell count, and packed cells and blood volumes, with no significant change in plasma volume. These results confirm an accelerated erythropoiesis process in ascitic birds. Increased blood cell production in ascitic birds was matched by an increase (P < 0.05) in the proportion of immature red blood cells (23%) in comparison with broilers that remained healthy (7%), and by decreased (P < 0.05) hemoglobin content relative to red blood cells. We conclude that continually increased corticosterone concentrations, as an inducer of erythropoiesis proliferation and differentiation arrest, in ascitic chickens, resulted in increased production of red blood cells (partially immature) with decreased hemoglobin content; this decrease in hemoglobin might have contributed to enhanced development of hypoxemia and to aggravation of the syndrome.

Review article: volume expansion in patients with cirrhosis

Adequate size and distribution of the circulating medium are important for cardiovascular function, tissue oxygenation, and fluid homoeostasis. Patients with cirrhosis have cardiovascular dysfunction with a hyperkinetic systemic circulation, abnormal distribution of the blood volume, vasodilation with low systemic vascular resistance, increased whole-body vascular compliance, and increased arterial compliance. The effectiveness and temporal relations of plasma/blood volume expansion depend highly on the type of load (water, saline, oncotic material, red blood cells). Patients with cirrhosis respond in some aspects differently from healthy subjects, owing to their disturbed circulatory function and neurohormonal activation. Thus the increase in cardiac output and suppression of the renin-angiotensin-aldosterone system and sympathetic nervous system during volume expansion may be somewhat blunted, and in advanced cirrhosis, especially the non-central parts of the circulation, including the splanchnic blood volume, are expanded by a volume load. Infusion of oncotic material (preferably albumin) is important in the prevention of post-paracentesis circulatory dysfunction. In conclusion, volume expansion in advanced cirrhosis is qualitatively and quantitatively different from that of healthy subjects, and in those with early cirrhosis. Timely handling is essential, but difficult as it is a balance between the risks of excess extravascular volume loading and further circulatory dysfunction in these patients with a hyperdynamic, but hyporeactive, circulation.

Review article: albumin for circulatory support in patients with cirrhosis

Renal function abnormalities and ascites in cirrhosis are the final consequence of a circulatory dysfunction characterized by marked splanchnic arterial vasodilation. This causes a reduction in effective arterial blood volume and the homoeostatic activation of vasoconstrictor and sodium-retaining systems. Albumin is very effective in preventing renal failure associated with large-volume paracentesis and spontaneous bacterial peritonitis, conditions that are known to cause an impairment of circulatory function in patients with cirrhosis and ascites. Moreover, albumin administration improves survival in patients with spontaneous bacterial peritonitis. In patients with hepatorenal syndrome the administration of vasoconstrictor drugs in combination with albumin improves circulatory and renal function markedly and survival slightly. By contrast, the administration of albumin without vasoconstrictors has marginal or no effects on renal function in this setting.

Blood volume distribution in patients with cirrhosis: aspects of the dual-head gamma-camera technique

BACKGROUND/AIMS

Patients with cirrhosis have increased total blood volume (TBV). The size of the "effective" blood volume has been closely investigated, whereas the distribution of the blood volume outside the thorax has not been examined. The aim was to estimate the blood volume distribution in patients with cirrhosis and portal hypertension, using a dual-head gamma-camera technique (DHGCT) and to validate this technique.

METHODS

Twenty-three patients with cirrhosis, 11 non-cirrhotic control patients, and six healthy controls had their blood volume distribution determined by the DHGCT.

RESULTS

The close relation between the estimated blood volume in the thorax region and the central and arterial blood volume, obtained by the dynamic indicator dilution technique (r=0.87, P<0.001), indicates validity of the DHGCT. Whole-body scintigraphy showed altered blood volume distribution in the cirrhotic patients with increased splanchnic blood volume (SpBV: 25.0 vs. 18.2% of TBV in controls, P<0.001), and all but one patient with hepatic venous pressure gradient above 12 mmHg had SpBV above 20% of TBV, but the blood volumes in the liver region were similar.

CONCLUSIONS

DHGCT is a valid method of estimating the blood volume distribution. Patients with cirrhosis and portal hypertension have grossly increased blood pooling in the splanchnic region, indicating splanchnic congestion.

Abdominal decompression plays a major role in early postparacentesis haemodynamic changes in cirrhotic patients with tense ascites

BACKGROUND

Some cirrhotic patients with tense ascites who undergo paracentesis develop a circulatory dysfunction syndrome, manifested by an increase in plasma renin activity. Recently, a significant inverse correlation between postparacentesis changes in plasma renin activity and systemic vascular resistance has been demonstrated in these patients, suggesting that peripheral arterial vasodilatation could be responsible for this circulatory dysfunction, but the mechanisms by which tense ascites removal induces such changes are unknown

AIM

To investigate the role of a decrease in intra-abdominal pressure (IAP) in the development of early postparacentesis haemodynamic changes

METHODS

Eleven cirrhotic patients with tense ascites received a large volume paracentesis. A specially designed pneumatic girdle was used to compress the abdomen to avoid a decrease in IAP during ascites removal. Haemodynamic studies were performed before paracentesis, one hour after ascites flow stopped, and 30 minutes after pneumatic girdle deflation

RESULTS

When IAP was maintained at its original level, no haemodynamic changes were observed, despite large volume paracentesis. However, a significant decrease in systemic vascular resistance was seen immediately after pneumatic girdle deflation

CONCLUSIONS

Early haemodynamic changes after paracentesis are avoided if IAP is maintained at its original level. The abrupt decrease in IAP could be the trigger for the development of the initial haemodynamic changes that eventually produce postparacentesis circulatory dysfunction.

Dynamics of albumin in plasma and ascitic fluid in patients with cirrhosis

BACKGROUND/AIMS

To determine dynamics of albumin in plasma and ascitic fluid of patients with cirrhosis.

METHODS

Forty-seven patients were classified in four groups: I--patients without fluid retention; II--patients with ascites not resistant to subsequent diuretic treatment; III--recompensated patients during diuretic treatment; and IV--patients with diuretic-resistant ascites. Transvascular and transperitoneal albumin transports were quantified by 131I-/125I-labelled human albumin.

RESULTS

TER(P) (i.e. the fraction of intravascular albumin (IVM) passing from plasma into the interstitial space per hour) was increased in all groups. In group IV patients the transport rate of albumin from plasma into the ascitic fluid (TER(PA)) was significantly higher than the transport rate from the ascitic fluid back into the plasma: TER(AP) (0.45 vs. 0.26% IVM/h, P < 0.002). In group II patients TER(PA) was similar to TER(AP) (0.27 vs. 0.25% IVM/h, ns). A direct correlation was found between TER(PA) and TER(AP) in both groups of patients (r = 0.78, P < 0.001).

CONCLUSION

In non-resistant ascites, there is a steady state between the transport of albumin into the peritoneal cavity and back into the plasma, but in resistant ascites the former transport is elevated. Thus, local factors may be important to treatment of ascites.

Ascites

This article reviews the progress made during the last century in understanding and managing ascites. The list of known causes of ascites has lengthened considerably. There is improved understanding of the mechanism of ascites formation and the pathophysiology of the renal sodium retention that accompanies portal hypertensive ascites. Management of ascites has become substantially easier with the advent of new diuretics, and new procedures such as peritoneovenous shunting, transjugular intrahepatic portosystemic stent placement, and liver transplantation.

Tumor necrosis factor and interleukin-6 in spontaneous bacterial peritonitis in cirrhosis: relationship with the development of renal impairment and mortality

Spontaneous bacterial peritonitis (SBP) is associated with an important production of inflammatory mediators. However, it is unknown whether there is a relationship between the abdominal production of these mediators and the development of renal impairment, one of the most important prognostic parameters in spontaneous bacterial peritonitis. We studied 52 cirrhotic patients at diagnosis and resolution of the infection, by measuring endotoxin, tumor necrosis factor (TNF), and interleukin-6 (IL-6) levels in plasma and ascitic fluid. Thirteen patients (25%) developed renal impairment. Patients developing renal impairment showed significantly higher plasma and ascitic fluid cytokine levels at diagnosis of infection than patients who did not (plasma TNF-alpha: 96.0+/-38.7 vs. 39.1+/-3.6 pg/mL, P=.0209; ascitic fluid TNF-alpha: 474.5+/-118.1 vs. 160.8+/-42.7 pg/mL, P=.0173; plasma IL-6: 6,635+/-2,897 vs. 458+/-109 pg/mL, P=.0004; ascitic fluid IL-6: 182,559+/-47,328 vs. 39,250+/-10,803 pg/mL, P=.0001). Independent predictors of development of renal impairment at diagnosis were: renal failure (blood urea nitrogen > 30 mg/dL or serum creatinine > 1.5 mg/dL) (P < .001), IL-6 levels in ascitic fluid (P < .001), and mean arterial pressure (P < .05). Ten of the 13 (77%) patients who developed renal impairment died during hospitalization, but only 2 of the 39 (5%) patients who did not (P=.0001). In addition, renal failure at diagnosis of the infection was the only independent predictor of hospital mortality (P < .001). In conclusion, the inflammatory response to the infection may be an important mechanism of renal impairment and the associated mortality in SBP.

Hemodynamic changes in patients developing effective hypovolemia after total paracentesis

BACKGROUND/AIMS

In many centers paracentesis is considered the treatment of choice for tense ascites. However, the mechanism of effective hypovolemia after paracentesis, the main complication associated with this procedure, remains unknown. In the current study, systemic hemodynamics was sequentially studied before and after total paracentesis in 46 patients with cirrhosis and tense ascites. The aim of the study was to assess the mechanism of effective hypovolemia after paracentesis.

METHODS

Plasma renin activity and aldosterone, mean arterial pressure, cardiac output (ECO-Doppler) and systemic vascular resistance were measured before, and 3 h, 6 h and 6 days after total paracentesis associated with plasma volume expansion.

RESULTS

Effective hypovolemia after paracentesis (defined as 50% increase in plasma renin activity up to a level over 4 ng x m(-1) x h(-1) at the 6th day after paracentesis) occurred in 20 cases [plasma renin activity increased from 8+/-17 to 19+/-2.7 ng x m(-1) x h(-1)]. In the remaining 26 cases no changes in plasma renin activity [8.5+/-2.4 vs. 8.7+/-2.2 ng x m(-1) x h(-1)] were observed. The amounts of ascitic fluid volume removed were similar. Effective hypovolemia after paracentesis was associated with a significant decrease in mean arterial pressure (89+/-2 vs. 81+/-3 mmHg) and systemic vascular resistance [1263+/-67 vs. 1014+/-80 dyn x s(-1) x cm(-5)] 6 days after treatment. In contrast, no significant changes in these parameters were observed in patients not developing this complication. In the whole group of patients a significant inverse relation was observed between changes in plasma renin activity and in systemic vascular resistance (r=0.74;p< 0.001).

CONCLUSIONS

These results indicate that effective hypovolemia after paracentesis in cirrhosis is predominantly due to an accentuation of the arteriolar vasodilation already present in these patients.