Plasma renin activity and urinary sodium excretion as prognostic indicators in nonazotemic cirrhosis with ascites

Evidence-based hyponatremia management in liver disease

Hyponatremia is primarily a water balance disorder associated with high morbidity and mortality. The pathophysiological mechanisms behind hyponatremia are multifactorial, and diagnosing and treating this disorder remains challenging. In this review, the classification, pathogenesis, and step-by-step management approaches for hyponatremia in patients with liver disease are described based on recent evidence. We summarize the five sequential steps of the traditional diagnostic approach: 1) confirm true hypotonic hyponatremia, 2) assess the severity of hyponatremia symptoms, 3) measure urine osmolality, 4) classify hyponatremia based on the urine sodium concentration and extracellular fluid status, and 5) rule out any coexisting endocrine disorder and renal failure. Distinct treatment strategies for hyponatremia in liver disease should be applied according to the symptoms, duration, and etiology of disease. Symptomatic hyponatremia requires immediate correction with 3% saline. Asymptomatic chronic hyponatremia in liver disease is prevalent and treatment plans should be individualized based on diagnosis. Treatment options for correcting hyponatremia in advanced liver disease may include water restriction; hypokalemia correction; and administration of vasopressin antagonists, albumin, and 3% saline. Safety concerns for patients with liver disease include a higher risk of osmotic demyelination syndrome.

Heart rate variability is associated with disease severity and portal hypertension in cirrhosis

INTRODUCTION

Autonomic nervous system activity in cirrhotic portal hypertension is linked to hyperdynamic circulation. Heart rate variability (HRV) is a validated noninvasive method to assess the sympathovagal balance. To investigate the correlation between HRV parameters and degree of portal hypertension, we studied a cohort of patients with cirrhosis accounting for etiology and treatments.

PATIENTS AND METHODS

In this cross-sectional, observational cohort study, 157 outpatients of both sex with nonalcoholic cirrhosis were assessed by upper gastrointestinal endoscopy to search for esophagogastric varices. Twenty-four-hour electrocardiogram Holter monitoring with 3 HRV parameters measurement [SD of the NN intervals, root mean square successive difference of NN intervals, and SD of the averages of NN intervals (SDANN)] according to time-domain analysis were performed in all patients. Sixteen patients with large esophagogastric varices underwent measurements of the HVPG and assessment of HRV parameters at baseline and after 45 days on carvedilol.

RESULTS

The liver dysfunction, expressed by Child-Pugh class or MELD score, was directly related to root mean square successive difference of NN intervals and inversely related to SDANN. Presence of ascites was inversely related to SDANN and to SD of the NN intervals. Treatment with carvedilol had an inverse relation with SDANN. Presence and size of esophagogastric varices had an inverse relation to SDANN and SD of the NN intervals. Upon multivariate analysis the associations between SDANN and Child-Pugh class, size of varices and ascites were confirmed. In the subgroup of 16 patients undergoing HVPG measurement, pressure gradient was unrelated to heart rate and HRV parameters.

CONCLUSIONS

Time-domain HRV parameters in patients with cirrhosis, confirm the autonomic nervous system alteration, and their correlation to the degree of portal hypertension suggesting a role of the ANS in hepatic decompensation.

Exploration of sodium homeostasis and pharmacokinetics in bile duct-ligated rats treated by anti-cirrhosis herbal formula plus spironolactone

Renal sodium retention is an essential indicator that is used for the prognosis of cirrhosis with ascites that requires diuretic treatment to restore sodium homeostasis. The diuretic effects of Yin-Chen-Hao-Tang (YCHT) alone or in combination with diuretics for sodium retention in patients with cirrhosis have not been investigated. This study aimed to investigate the diuretic effects and sodium retention caused by YCHT with spironolactone, from both the pharmacokinetic and pharmacodynamic perspective, in bile duct-ligated rats. The HPLC method was validated and utilized for the pharmacokinetic analysis of rat urine. Urine samples were collected and analyzed every 4 hours for 32 h after oral administration of YCHT at 1 or 3 g/kg daily for 5 days in bile duct-ligated rats. A dose of 20 mg/kg spironolactone was also administered to pretreat the YCHT 1 g/kg or the 3 g/kg group on the 5th day to explore the interaction of the two treatments. Urine sodium, potassium, weight, volume, and spironolactone and canrenone levels were measured to investigate fluid homeostasis after the coadministration. The linearity, precision, and accuracy of the HPLC method were suitable for subsequent urinary pharmacokinetic analyses. The pharmacokinetic parameters in the 1 g/kg YCHT with spironolactone group revealed that the elimination half-life of the spironolactone metabolite, canrenone, was prolonged. In addition, the cumulative excretion amount, the area under the rate curve (AURC), and the maximum rate of excretion (Rmax) were significantly decreased when the spironolactone group was pretreated with 3 g/kg YCHT. Urinary sodium excretion elicited by spironolactone was suppressed by pretreatment with 1 or 3 g/kg YCHT. The 32-hour urine output was not altered by the administration of YCHT alone, but it was significantly decreased by 64.9% after the coadministration of YCHT with spironolactone. The interaction of spironolactone and YCHT was found to decrease urine sodium-potassium and water excretion, and this change was attributed to the decreased level of spironolactone metabolites and possibly the regulation of the renin-angiotensin-aldosterone system by obstructed cirrhosis. The dose adjustment of YCHT or diuresis monitoring should be noted when co-administering YCHT and spironolactone to treat hepatic diseases clinically.

The differential activation of cardiovascular hormones across distinct stages of portal hypertension predicts clinical outcomes

Background and aims

The cardiovascular hormones renin/angiotensin/aldosterone (RAA), brain-type natriuretic peptide (BNP)and arginine-vasopressin (AVP) are key regulators of systemic circulatory homeostasis in portal hypertension (PH). We assessed (i) the activation of renin, BNP and AVP across distinct stages of PH and (ii) whether activation of these hormones correlates with clinical outcomes.

Methods

Plasma levels of renin, proBNP and copeptin (AVP biomarker) were determined in 663 patients with advanced chronic liver disease (ACLD) undergoing hepatic venous pressure gradient (HVPG) measurement at the Vienna General Hospital between 11/2011 and 02/2019. We stratified for Child stage (A–C), HVPG (6–9 mmHg, 10–15 mmHg, ≥ 16 mmHg) and compensated vs. decompensated ACLD.

Results

With increasing PH, hyperdynamic state was indicated by higher heart rates (6–9 mmHg: median 71.0 [IQR 18.0] bpm, 10–15 mmHg: 76.0 [19.0] bpm, ≥ 16 mmHg: 80.0 [22.0] bpm; p < 0.001), lower mean arterial pressure (6–9 mmHg: 103.0 [13.5] mmHg, 10–15 mmHg: 101.0 [19.5] mmHg, ≥ 16 mmHg: 99.0 [21.0] mmHg; p = 0.032) and lower serum sodium (6–9 mmHg: 139.0 [3.0] mmol/L, 10–15 mmHg: 138.0 [4.0] mmol/L, ≥ 16 mmHg: 138.0 [5.0] mmol/L; p < 0.001). Across HVPG strata (6–9 mmHg vs. 10–15 mmHg vs ≥ 16 mmHg), median plasma levels of renin (21.0 [50.5] vs. 25.1 [70.9] vs. 65.4 [219.6] µIU/mL; p < 0.001), proBNP (86.1 [134.0] vs. 63.6 [118.0], vs. 132.2 [208.9] pg/mL; p = 0.002) and copeptin (7.8 [7.7] vs. 5.6 [8.0] vs. 10.7 [18.6] pmol/L; p = 0.024) increased with severity of PH. Elevated renin levels independently predicted first hepatic decompensation (adjusted hazard ratio [aHR]: 1.69; 95% confidence interval [95% CI] 1.07–2.68; p = 0.025) and mortality in compensated patients (aHR: 3.15; 95% CI 1.70–5.84; p < 0.001) and the overall cohort aHR: 1.42; 95% CI 1.01–2.01; p = 0.046). Elevated copeptin levels predicted mortality in decompensated patients (aHR: 5.77; 95% CI 1.27–26.33; p = 0.024) and in the overall cohort (aHR: 3.29; 95% CI 1.36–7.95; p = 0.008). ProBNP levels did not predict clinical outcomes.

Conclusions

The cardiovascular hormones renin, proBNP and AVP are activated with progression of ACLD and PH. Renin activation is a risk factor for hepatic decompensation and mortality, especially in compensated patients. Increased plasma copeptin is a risk factor for mortality, in particular in decompensated patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12072-021-10203-9.

Analysis of factors predicting the response to tolvaptan in patients with liver cirrhosis and hepatic edema

BACKGROUND AND AIM

This study aimed to clarify the factors predictive of treatment response to tolvaptan (V2-receptor antagonist) for cirrhotic patients with hepatic edema in a real-world setting.

METHODS

In this retrospective, multicenter study, tolvaptan was orally administered at a dose of 7.5 mg once a day. Patients with a decrease in body weight of 1.5 kg or greater from baseline were characterized as responders at day 7.

RESULTS

Of 229 patients, 210 were subjected to this analysis. Patients consisted of 133 men and 77 women, with the median age of 67 years (range, 40-89 years). According to the Child-Pugh classification, five patients were classified as class A, 90 as class B, and 115 as class C. The frequencies of responders and nonresponders were 55.2% and 44.8%, respectively. Blood urea nitrogen (BUN) level was significantly lower in responders compared with nonresponders (P = 3.77 × 10^-3 ). Using the receiver operating characteristic curve, the cutoff value of 28.2 mg/dL was the most useful in discriminating responders from nonresponders. Among 154 patients with BUN level of less than 28.2 mg/dL, 95 (61.7%) were responders. By contrast, among 56 patients with BUN level of 28.2 mg/dL or more, 21 (37.5%) were nonresponders (P = 2.70 × 10^-3 ). On multivariate analysis, BUN level of <28.2 mg/dL and urine sodium >51 mEq/day were found to be independent factors associated with the response to tolvaptan.

CONCLUSIONS

This study suggests that BUN level and urinary sodium excretion are closely associated with the response to tolvaptan in cirrhotic patients with hepatic edema.

Clinical Features of Refractory Ascites in Outpatients

OBJECTIVES:

To present the clinical features and outcomes of outpatients who suffer from refractory ascites.

METHODS:

This prospective observational study consecutively enrolled patients with cirrhotic ascites who submitted to a clinical evaluation, a sodium restriction diet, biochemical blood tests, 24 hour urine tests and an ascitic fluid analysis. All patients received a multidisciplinary evaluation and diuretic treatment. Patients who did not respond to the diuretic treatment were controlled by therapeutic serial paracentesis, and a transjugular intrahepatic portosystemic shunt was indicated for patients who required therapeutic serial paracentesis up to twice a month.

RESULTS:

The most common etiology of cirrhosis in both groups was alcoholism [49 refractory (R) and 11 non-refractory ascites (NR)]. The majority of patients in the refractory group had Child-Pugh class B cirrhosis (p=0.034). The nutritional assessment showed protein-energy malnutrition in 81.6% of the patients in the R group and 35.5% of the patients in the NR group, while hepatic encephalopathy, hernia, spontaneous bacterial peritonitis, upper digestive hemorrhage and type 2 hepatorenal syndrome were present in 51%, 44.9%, 38.8%, 38.8% and 26.5% of the patients in the R group and 9.1%, 18.2%, 0%, 0% and 0% of the patients in the NR group, respectively (p=0.016, p=0.173, p=0.012, p=0.012, and p=0.100, respectively). Mortality occurred in 28.6% of the patients in the R group and in 9.1% of the patients in the NR group (p=0.262).

CONCLUSION:

Patients with refractory ascites were malnourished, suffered from hernias, had a high prevalence of complications and had a high postoperative death frequency, which was mostly due to infectious processes.

Transjugular Intrahepatic Portosystemic Shunts With Covered Stents Increase Transplant-Free Survival of Patients With Cirrhosis and Recurrent Ascites

BACKGROUND & AIMS

There is controversy over the ability of transjugular intrahepatic portosystemic shunts (TIPS) to increase survival times of patients with cirrhosis and refractory ascites. The high rate of shunt dysfunction with the use of uncovered stents counteracts the benefits of TIPS. We performed a randomized controlled trial to determine the effects of TIPS with stents covered with polytetrafluoroethylene in these patients.

METHODS

We performed a prospective study of 62 patients with cirrhosis and at least 2 large-volume paracenteses within a period of at least 3 weeks; the study was performed at 4 tertiary care centers in France from August 2005 through December 2012. Patients were randomly assigned to groups that received covered TIPS (n = 29) or large-volume paracenteses and albumin as necessary (LVP+A, n = 33). All patients maintained a low-salt diet and were examined at 1 month after the procedure then every 3 months until 1 year. At each visit, liver disease-related complications, treatment modifications, and clinical and biochemical variables needed to calculate Child-Pugh and Model for End-Stage Liver Disease scores were recorded. Doppler ultrasonography was performed at the start of the study and then at 6 and 12 months after the procedure. The primary study end point was survival without a liver transplant for 1 year after the procedure.

RESULTS

A higher proportion of patients in the TIPS group (93%) met the primary end point than in the LVP+A group (52%) (P = .003). The total number of paracenteses was 32 in the TIPS group vs 320 in the LVP+A group. Higher proportions of patients in the LVP+A group had portal hypertension-related bleeding (18% vs 0%; P = .01) or hernia-related complications (18% vs 0%; P = .01) than in the TIPS group. Patients in LVP+A group had twice as many days of hospitalization (35 days) as the TIPS group (17 days) (P = .04). The 1-year probability of remaining free of encephalopathy was 65% for each group.

CONCLUSIONS

In a randomized trial, we found covered stents for TIPS to increase the proportion of patients with cirrhosis and recurrent ascites who survive transplantation-free for 1 year, compared with patients given repeated LVP+A. These findings support TIPS as the first-line intervention in such patients. ClinicalTrials.gov ID: NCT00222014.

Plasma renin concentration represents an independent risk factor for mortality and is associated with liver dysfunction in patients with cirrhosis

BACKGROUND AND AIM

Plasma renin concentration (PRC) is increased in patients with cirrhosis. The aims of this study were to evaluate the relation of PRC to (i) portal hypertension, (ii) degree of liver dysfunction, and (iii) survival.

METHODS

Plasma renin concentration (range 2.8-39.9 μU/mL) was measured after 30 min in supine position. Also, hepatic venous pressure gradient (HVPG), Child-Pugh (CPS), model for end-stage liver disease scores and transient elastography values (TE, Fibroscan) were evaluated at this time. Mortality was recorded during follow-up.

RESULTS

One hundred fifty cirrhotic patients (age 55 ± 11 years; 73% male; CPS A 41.3%/B 41.3%/C 17.3%) were included. Mean HVPG was 16.6 ± 6.5 mmHg. Median PRC according to CPS was A 15.45 μU/mL (95%CI 1.56-261.5), B 37.3 μU/mL (95%CI 4.29-1317.65), and C 175.3 μU/mL (95%CI 5.3-5684; P < 0.001). In patients with clinical significant portal hypertension (HVPG ≥ 10 mmHg, n = 123) median PRC was 31.2 μU/mL (95%CI 2.76-1345.4), in those without was 13.7 μU/mL (95%CI 2.7-428.2; P = 0.009). Significantly higher TE values (33.2 [13-75] vs 59.65 kPa [14.5-75]; P = 0.014) were found in patients with elevated PRC. Median follow up was 711 days (95%CI 24-1152). Twenty-two (36.1%) of the 61 patients with elevated PRC and 11 of the 89 (12.4%) with normal PRC died (P = 0.001). Median PRC was significantly higher in patients that died (83.6 μU/mL [3.39-4451.9] vs 21.5 μU/mL [2.6-1197.9]; P = 0.001). Elevated PRC (P = 0.005; HR 3.36; 95%CI 1.46-7.85), hepatocellular carcinoma (P < 0.001; HR 10.68; 95%CI 3.64-31.3), CPS B (P = 0.013; HR 3.69; 95%CI 1.31-10.4) and CPS C (P = 0.008; HR 5.36; 95%CI 1.54-18.62) emerged as independent risk factors for mortality.

CONCLUSIONS

In cirrhotic patients PRC correlates with the severity of portal hypertension and liver dysfunction. Moreover, elevated PRC represents an independent risk factor for mortality.

Rifaximin and midodrine improve clinical outcome in refractory ascites including renal function, weight loss, and short-term survival

BACKGROUNDS AND AIMS

The occurrence of refractory ascites in nearly 17% of patients with decompensated cirrhosis is an unresolved issue. Advanced liver disease, functional renal impairment, and vascular insensitivity to vasopressors are the main causes of its refractoriness. Therefore, the aim of this study was to evaluate the impact on diuresis, weight loss, and short-term survival if midodrine and rifaximin were added to the diuretic therapy (DT).

MATERIALS AND METHODS

The study evaluated the eligibility of 650 patients with cirrhosis and refractory ascites who were selected during the period from November 2011 to May 2015. A total of 50 patients were excluded and finally 600 were selected and divided into the following groups: patients exposed to DT (n=200) as a control group, or DT with midodrine and rifaximin group (n=400). Body weight, mean arterial pressure, and glomerular filtration rate were determined. Plasma renin and aldosterone were also determined. Follow-up was performed after 2, 6, and 12 weeks, and then every 2 months for 24 months.

RESULTS

The mean arterial pressure was significantly higher in the midodrine and rifaximin group (P=0.000), and there was a highly significant weight loss after 12 weeks (12.5 kg) (P=0.000), a highly significant increase in serum sodium, urine output, and urinary sodium excretion (P=0.000), and creatinine clearance was more reduced in the control group. With rifaximin and midodrine, a complete response occurred in 310 (78%) patients, a partial response in 72 (18%), and no response in 18 (4%) versus 30 (15%), 110 (55%), and 60 (30%) in the control group, respectively (P=0.000). Midodrine and rifaximin significantly reduced paracentesis needs when compared with the controls (18 study patients vs. 75 DT-only patients, P=0.000).

CONCLUSION

Adding rifaximin and midodrine to DT enhanced diuresis in refractory ascites with improved systemic, renal hemodynamics and short-term survival.

Mineralocorticoid receptor antagonists as diuretics: Can congestive heart failure learn from liver failure?

Despite significant improvements in diagnosis, understanding the pathophysiology and management of the patients with acute decompensated heart failure (ADHF), diuretic resistance, yet to be clearly defined, is a major hurdle. Secondary hyperaldosteronism is a pivotal factor in pathogenesis of sodium retention, refractory congestion in heart failure (HF) as well as diuretic resistance. In patients with decompensated cirrhosis who suffer from ascites, similar pathophysiological complications have been recognized. Administration of natriuretic doses of mineralocorticoid receptor antagonists (MRAs) has been well established in management of cirrhotic patients. However, this strategy in patients with ADHF has not been well studied. This article will discuss the potential use of natriuretic doses of MRAs to overcome the secondary hyperaldosteronism as an alternative diuretic regimen in patients with HF.

Hyponatremia in Cirrhosis--Pathogenesis, Treatment, and Prognostic Significance

Cirrhosis is characterized by systemic and splanchnic vasodilation that leads to excessive nonosmotic secretion of vasopressin (antidiuretic hormone). Hyponatremia is a common electrolyte abnormality in advanced liver disease that results from the impaired ability of the kidney to excrete solute-free water that leads to "dilutional" hyponatremia-water retention disproportionate to the retention of sodium. Hyponatremia in liver diseases carries the prognostic burden, correlates with the severity of cirrhosis, and, in recent studies, has also been implicated in the pathogenesis of hepatic encephalopathy. The current treatment options are limited to conventional therapies like fluid restriction, and the outcomes are unsatisfactory. Although currently available vasopressin (V2 receptors) antagonists have been shown to increase serum sodium concentrations and improve ascites control, their role in the treatment of hyponatremia in liver disease patients remains questionable because of adverse effect profiles, high cost, and poor data on long-term mortality benefits. More information is needed to argue the benefits vs risks of short-term use of vaptans for correction of hyponatremia especially just hours-to-days before liver transplant.

The Kidney in Pediatric Liver Disease

There is an intricate relationship between the liver and the kidney, with renal physiology and function intimately involved in many primary disorders of pediatric liver disease. The hemodynamic changes of progressive cirrhosis affect and are directly affected by changes in renal blood flow and renal handling of sodium and free water excretion. Resulting complications of worsening ascites, hyponatremia, and acute kidney injury frequently complicate the care of children with advanced liver disease and contribute significant morbidity and mortality. While liver transplantation may restore hemodynamic stability, nearly 40% of pediatric liver transplant recipients develop chronic kidney disease post-transplant and approximately 25% are left with clinical hypertension. This review seeks to provide a basic understanding of this relationship to enable the provision of optimal care to children with liver disease.

Hyponatremia in cirrhosis: Pathophysiology and management

Hyponatremia is frequently seen in patients with ascites secondary to advanced cirrhosis and portal hypertension. The development of ascites in patients with cirrhosis is multi-factorial. Portal hypertension and the associated systemic vasodilation lead to activation of the sodium-retaining neurohumoral mechanisms which include the renin-angiotensin-aldosterone system, sympathetic nervous system and antidiuretic hormone (ADH). The net effect is the avid retention of sodium and water to compensate for the low effective circulatory volume resulting in the development of ascites. Although not apparent in the early stages of cirrhosis, the progression of cirrhosis and ascites leads to impairment of the kidneys to eliminate solute- free water. This leads to additional compensatory mechanisms including non-osmotic secretion of ADH, also known as arginine vasopressin, further worsening excess water retention and thereby hyponatremia. Hyponatremia is associated with increased morbidity and mortality in patients with cirrhosis, and is an important prognostic marker both before and after liver transplant. The management of hyponatremia in this setting is a challenge as conventional therapy for hyponatremia including fluid restriction and loop diuretics are frequently inefficacious. In this review, we discuss the pathophysiology and various treatment modalities, including selective vasopressin receptor antagonists, for the management of hyponatremia in patients with cirrhosis.

Systemic vascular resistance in cirrhosis: a predictor of severity?

Background

The aim of this study was to investigate whether systemic vascular resistance (SVR) correlates with validated prospective scoring systems such as Model for End-stage Liver Disease (MELD) and its modifications.

Methods

Patients with cirrhosis, who were admitted to hospital with decompensation (as defined by development of ascites, hepatic encephalopathy, and variceal bleeding) and underwent echocardiography were included in this study. Laboratory data required for computing MELD score, serum bilirubin, serum creatinine, international normalized ratio, and serum sodium were collected for every patient. We tabulated hemodynamic and echocardiography parameters that enabled calculation of SVR. We analyzed the correlation between SVR and each of the individual prognostic scores.

Results

A total of 771 patients with a diagnosis of decompensated cirrhosis were included in the study. Two hundred and sixty-two patients were found to have a low sodium level (<135 mEq/L) and 509 were found to have a normal sodium level (>135 mEq/L). In the patients with hyponatremia, we found statistically significant inverse correlations between SVR and validated liver severity models. However, these correlations were not seen in patients with normonatremia.

Conclusion

We observed a statistically significant inverse correlation between SVR and all the validated liver disease severity models used in this study among patients with hyponatremia but not in those with normonatremia.

Review article: advances in the management of patients with cirrhosis and portal hypertension-related renal dysfunction

BACKGROUND

In cirrhosis, portal hypertension is associated with a spectrum of renal dysfunction that has significant implications for morbidity and mortality.

AIM

To discuss recent progress in the patho-physiological mechanisms and therapeutic options for portal hypertension-related renal dysfunction.

METHODS

A literature search using Pubmed was performed.

RESULTS

Portal hypertension-related renal dysfunction occurs in the setting of marked neuro-humoral and circulatory derangement. A systemic inflammatory response is a pathogenetic factor in advanced disease. Such physiological changes render the individual vulnerable to further deterioration of renal function. Patients are primed to develop acute kidney injury when exposed to additional 'hits', such as sepsis. Recent progress has been made regarding our understanding of the aetiopathogenesis. However, treatment options once hepatorenal syndrome develops are limited, and prognosis remains poor. Various strategies to prevent acute kidney injury are suggested.

CONCLUSION

Prevention of acute kidney injury in high risk patients with cirrhosis and portal hypertension-related renal dysfunction should be a clinical priority.

A fascinating presentation of hepatic hydrothorax

We report this case of a 43-year-old woman with hepatitis-C cirrhosis who presented with a large right sided pleural effusion complicated by hypoxic respiratory failure and altered mentation necessitating dependence on mechanical ventilation. The pleural effusion spontaneously resolved upon initiation of mechanical positive pressure ventilation and recurred almost immediately after weaning the patient off the ventilator. The pre-ventilation, ventilation and post-ventilation chest X-ray films in chronological order present a striking visual demonstration of fluid dynamics and pathophysiology of hepatic hydrothorax, thereby obviating the need for a dedicated diagnostic test. We also report this case to highlight the treatment strategies for this often intractable complication.

Management of refractory ascites

Ascites that does not respond or recurs after high-dose diuresis and sodium restriction should be considered refractory ascites. As cirrhosis advances, the escaping fluid overwhelms the lymphatic return. Decrease in renal plasma flow leads to increased sodium reabsorption at the proximal tubule leading to decreased responsiveness to loop diuretics and mineralocorticoid antagonists, which work distally. These complex hemodynamic alterations lead to refractory ascites. In refractory ascites, high-dose diuresis (400 mg of spironolactone and 160 mg of furosemide) and sodium restriction (<90 mmol/d) result in inadequate weight loss and sub optimal sodium excretion (<78 mmol/d). Further use of diuretics is limited by complications such as encephalopathy, azotemia, renal insufficiency, hyponatremia, and hyperkalemia. Therapy for refractory ascites is limited. The available therapies are repeated large volume paracentesis (LVP), transjugular intrahepatic portosystemic shunts, peritoneovenous shunts, investigational medical therapies, and liver transplantation. LVP with concomitant volume expanders is the initial treatment of choice. Transjugular intrahepatic portosystemic seems to be superior to LVP in reducing the need for repeated paracentesis and improves the quality of life. Several treatments that act at different steps in the pathogenesis of ascites are investigational, and some show promising results. Splanchnic and peripheral vasoconstrictors (Octreotide, Midodrine, and Terlipressin) increase effective arterial volume and decrease activation of the renin-angiotensin system with resultant increase in renal sodium excretion. Clonidine when given with spironolactone has been shown to cause rapid mobilization of ascites by significantly decreasing the sympathetic activity and renin-aldosterone levels. Natural aquaretics and synthetic V2 receptor antagonists (satavaptan) are being evaluated for mobilization of ascites by increasing the excretion of solute-free water. Liver transplantation remains the only definitive therapy for refractory ascites. Because refractory ascites is a poor prognostic sign, liver transplantation should be considered and incorporated early in the treatment plan.

Use of diuretics in heart failure and cirrhosis

Sodium and water retention in cardiac failure and cirrhosis is pivotal in the morbidity and mortality of patients with these disorders. Moreover, the pathophysiology of these edematous disorders is quite similar. Both disorders have activation of the renin-angiotensin-aldosterone system, increased sympathetic activity, and nonosmotic stimulation of arginine vasopressin, which is initiated by unloading of the arterial baroreceptors; this occurs secondary to diminished cardiac output with heart failure and primary systemic arterial vasodilation with cirrhosis. With this common pathophysiology causing pulmonary congestion, ascites, and peripheral edema, diuretics are pivotal in the therapy of patients with heart failure and cirrhosis. Advanced cardiac failure and cirrhosis both show secondary hyperaldosteronism and impaired renal escape from the sodium-retaining effect of aldosterone. However, currently there are contradictory uses of mineralocorticoid-receptor antagonists in cardiac failure (non-natriuretic doses) versus cirrhosis (natriuretic doses). This disparity relates to the greater potential of hyperkalemia in cardiac failure patients receiving inhibitors of the renin-angiotensin-aldosterone system. This review discusses the beneficial and potentially deleterious effects of diuretic use in patients with cardiac failure and cirrhosis.

Relationship of 24-hour ambulatory blood pressure and heart rate with markers of hepatic function in cirrhotic patients

Background

There is evidence that in cirrhotic patients, certain hemodynamic parameters, such as blood pressure and heart rate, are related to the severity of liver disease. This study investigated whether non-invasive 24-hour ambulatory blood pressure and heart rate are more closely associated with markers of liver disease severity than conventional office measurements.

Methods

Ambulatory patients with cirrhosis underwent office blood pressure and heart rate measurements, 24-hour ambulatory blood pressure monitoring and blood laboratory tests.

Results

Fifty-one patients (32 men, mean age 57.4 ± 11.3 years) completed the study. Twenty six patients had compensated liver cirrhosis (group A) and 25 patients had more advanced liver disease (group B). Group A and B patients differed significantly both in ambulatory asleep diastolic blood pressure (p < 0.05) and office diastolic blood pressure (p < 0.01), which were lower in more advanced liver disease. Office blood pressure and heart rate correlations were similar to or even stronger than ambulatory ones. Ambulatory blood pressure and heart rate awake-asleep variation (dipping) showed a relatively flat pattern as markers of liver dysfunction were deteriorating. The strongest correlations were found with both ambulatory and office heart rate, which increased as indicators of severity of liver disease were worsening.

Conclusions

Heart rate seems to be a more reliable marker of ongoing liver dysfunction than blood pressure. Evaluation of blood pressure and heart rate with 24-hour ambulatory measurement does not seem to offer more information than conventional office measurements.

Spot urinary sodium for assessing dietary sodium restriction in cirrhotic ascites

AIM: To evaluate the accuracy of spot urinary Na/K and Na/creatinine (Cr) ratios as an alternative to 24-h urinary sodium in monitoring dietary compliance in patients with liver cirrhosis and ascites treated with diuretics.

METHODS: The study was carried on 40 patients with liver cirrhosis and ascites treated with diuretic therapy. Patients were divided into two groups according to 24-h urinary sodium. We measured spot urine Na/K ratio, Na/Cr ratio and 24-h urinary sodium. Student’s t test was used to compare the interval variables and χ² test to compare the nominal variables between the two groups. Receiver operator characteristic curve was used to identify the best cutoff point for Na/K and Na/Cr ratio.

RESULTS: The best cutoff point for Na/K ratio was 2.5 (P < 0.001) and area under the curve (AUC) was 0.9, and for Na/Cr ratio, the best cutoff point was 35 (P < 0.001) and AUC was 0.885. Na/K ratio showed higher sensitivity and accuracy compared to Na/Cr ratio (87.5% and 87% for Na/K ratio; 81% and 85% for Na/Cr ratio, respectively).

CONCLUSION: Spot urine Na/K ratio has adequate accuracy for assessment of dietary sodium restriction compared with 24-h urinary sodium in patients with liver cirrhosis and ascites.

Renal failure in patients with cirrhosis

Renal failure in cirrhosis poses unique diagnostic and therapeutic challenges. Laboratory values and predictive equations grossly overestimate renal function in patients with cirrhosis. Development of renal failure connotes a worse prognosis; mortality is especially high with hepatorenal syndrome. Classification of the causes of renal failure in patients with cirrhosis is provided with more extensive discussion of selected causes. Finally, a suggested diagnostic approach to renal failure in cirrhosis is given.

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.

Hepatic venous pressure in practice: how, when, and why

Hepatic venous pressure gradient (HVPG) measurement has evolved into an extremely useful procedure for the assessment of portal hypertensive patients and in the prediction and management of portal hypertension-related events. Although invasive and not widely available, its safety and reproducibility can be warranted when performed in referral centers and following accepted guidelines. Well-established manometric HVPG cut off are reliable targets in the therapy of portal hypertension. When adequately indicated and performed, HVPG measurement provides valuable information allowing to establish diagnosis, elaborate prognosis, evaluate therapy and, most importantly, to make therapeutic decisions in portal hypertensive patients.

The transjugular route: the key hole to the liver world

Portal hypertensive complications are major causes of morbidity and mortality in patients with liver cirrhosis. The advent of the transjugular route with its minimal access allows non-surgical management of portal hypertension, therapy of venous complications of liver transplantation, monitoring of therapy for portal hypertension, hepatic venous pressure gradient and is also the major route to treat hepatic venous obstruction syndromes. In addition, the transjugular route is a safe route to perform a liver biopsy (transjugular liver biopsy) and allows retrograde evaluation of the portal vein. All these procedures can be combined in the same session. These hepatic interventional radiological skills should be incorporated into the expertise of the liver team in specialised hepatological centres, particularly in liver transplant centres as they are especially useful in improving outcomes of cirrhotic patients on the liver transplantation waiting list. A limitation in achieving this goal, could be the number of experienced radiologists, but hepatologists can be trained, at least for the most simple procedures (transjugular liver biopsy and hepatic venous pressure gradient). This would allow wider applicability and use of these diagnostic and therapeutic techniques, all through a 2 mm hole in the neck--the key hole to the liver world.

Management of ascites and hepatic hydrothorax

The natural course of patients with cirrhosis is frequently complicated by the accumulation of fluid in the peritoneal or pleural cavities and interstitial tissue. Functional renal abnormalities that occur as a consequence of decreased effective arterial blood volume are responsible for fluid accumulation in the form of ascites and hepatic hydrothorax. Ascites is the most common complication of cirrhosis and poses an increased risk for infections, renal failure and mortality. Patients have a poor prognosis and it is estimated that nearly half will die in approximately 2 years without liver transplantation. Hepatic hydrothorax is defined as a pleural effusion greater than 500 mL (mostly right-sided) in patients with cirrhosis without cardiopulmonary disease; the estimated prevalence is approximately 5-10%. Liver transplantation is the most definitive cure for both conditions in those patients that are suitable candidates. However, the mainstay of therapy for minimizing fluid accumulation in both conditions includes sodium restriction and administration of diuretics. This article reviews the most current concepts of pathogenesis, clinical findings, diagnosis, and treatment of these complications of cirrhosis.

Prognosis in patients with cirrhosis and mild portal hypertension

OBJECTIVE

Sixty to 70% of upper gastrointestinal bleeding episodes in patients with cirrhosis are caused by oesophageal varices. Prophylaxis is indicated in patients with varices and a hepatic venous pressure gradient (HVPG) above 12 mmHg. The study of the natural history of patients with lower HVPG has been sparse. In this study, long-term survival and the risk of complications in mild portal hypertension were analysed.

MATERIAL AND METHODS

Sixty-one patients with cirrhosis and HVPG below 10 mmHg were included in the study. Data were collected from medical files and National Patient Registries. Variceal bleeding, hepatic encephalopathy and death related to cirrhosis were registered. Thirty-nine patients were graded as Child class A, 19 as class B and 3 as class C. Median survival time was 11 years.

RESULTS

Twenty-eight patients (46%) developed one or more complications: variceal bleeding in 10 (16%) and hepatic encephalopathy in 18 patients (30%). Twenty-three patients (38%) died from complications of cirrhosis. Two patients (3%) died from variceal bleeding, another two (3%) from gastrointestinal bleeding of unidentified source. Survival rate was significantly decreased compared with that in the background population.

CONCLUSIONS

The frequency of complications in patients with mild portal hypertension is considerable, and guidelines for follow-up or medical prophylaxis are warranted. The risk of bleeding from oesophageal varices is low and bleeding-related deaths rare.

Volumenüberladung bei Herzinsuffizienz, nephrotischem Syndrom und Leberzirrhose

Volume retention in heart failure, nephrotic syndrome, and liver cirrhosis reflects pathological changes in homeostatic mechanisms that regulate the extracellular volume (sympathetic activity, renin-angiotensin-aldosterone system [RAAS], natriuretic peptides) and plasma osmolality (antidiuretic hormone [ADH]). In heart failure and liver cirrhosis, these changes are induced by a reduction of the effective circulating volume, which is the part of the extracellular fluid that is within the arterial system and effectively perfusing the tissues. This reduction in the effective circulating volume is caused by reduced cardiac output (heart failure), or by splanchnic vasodilatation with arterial underfilling (liver cirrhosis). In both cases, baroreceptors in both the carotid sinuses and in the glomerular afferent arterioles upregulate RAAS- and sympathetic activity, resulting in systemic vasoconstriction and renal sodium (and volume) retention. More severe reductions in the effective circulating volume may additionally stimulate ADH release, thus increasing the reabsorption of free water with subsequent hyponatriemia. In nephrotic syndrome, volume retention results either directly from the primary renal disease, which induces renal sodium and volume retention ("overfilling"), or indirectly from the reduced plasma oncotic pressure due to hypoalbuminemia, which induces a fluid shift from the intravascular to the interstitial space ("underfilling") with subsequent acitivation of baroreceptors and secondary sodium and volume retention.

Measurement of portal pressure: when, how, and why to do it

Many of the clinical complications of cirrhosis are the direct consequences of the evaluation of portal venous pressure (PVP). The degree of portal hypertension has been shown to correlate with the severity of liver disease, both functionally and histologically. Direct measurement of PVP, however, is invasive and cannot be routinely performed. As a surrogate, the hepatic venous pressure gradient (HVPG) has been widely accepted as a measurement of PVP. The ease, accuracy, and safety of HVPG measurement has made it a valuable tool in the research arena and, increasingly, in clinical practice.

Peritoneovenous shunt as a bridge to liver transplantation

Intractable ascites carries great morbidity. The aim of this study was to determine the efficacy of peritoneovenous shunt (PVS) in patients listed for liver transplantation (LT). Between January 1999 and January 2004, PVS was inserted in 36 (30 males and 6 females) cirrhotic patients, 50.3 years of median age (range: 30-66), who failed multiple large-volume paracenteses and diuretic therapy, when listed for LT. Data were collected until LT or the present time, and were compared to an historical cohort (1997-1998) as control. No operative death occurred. Four patients died before LT in a median delay of 9 months after PVS insertion. PVS provided palliation for intractable ascites in 30 patients (83%). Renal function significantly improved (glomerular filtration rate (GFR) improved from 0.642 to 0.987 mL/s, p<0.05). Eighteen patients were transplanted in a median delay of 6 months (range: 3-12 months) after PVS insertion. When compared to the historical cohort of 18 patients, the occurrence of post-LT acute renal failure was significantly lower in the PVS group (3/18 vs. 13/18, p<0.05). Our results suggest that PVS might be beneficial in patients with refractory ascites waiting for LT and could prevent postoperative acute renal failure.

MELD score and clinical type predict prognosis in hepatorenal syndrome: relevance to liver transplantation

Important progress has been made recently regarding the pathogenesis and treatment of hepatorenal syndrome (HRS). However, scant information exists about factors predicting outcome in patients with cirrhosis and HRS. Moreover, the prognostic value of the model of end-stage liver disease (MELD) score has not been validated in the setting of HRS. The current study was designed to assess the prognostic factors and outcome of patients with cirrhosis and HRS. The study included 105 consecutive patients with HRS. Forty-one patients had type 1 HRS, while 64 patients had type 2 HRS. Patients with type 1 HRS not only had more severe liver and renal failure than type 2 patients, they also had greater impairment of circulatory function, as indicated by lower arterial pressure and higher activation of vasoconstrictor factors. In the whole series, the median survival was 3.3 months. In a multivariate analysis of survival, only HRS type and MELD score were associated with an independent prognostic value. All patients with type 1 HRS had a high MELD score (> or =20) and showed an extremely poor outcome (median survival: 1 mo). By contrast, the survival of patients with type 2 HRS was longer and dependent on MELD score (> or =20, median survival 3 mo; <20, median survival 11 mo; P < .002). In conclusion, the outcome of patients with cirrhosis and HRS can be estimated by using two easily available variables, HRS type and MELD score. These data can be useful in the management of patients with HRS, particularly for patients who are candidates for liver transplantation.

Persistent ascites and low serum sodium identify patients with cirrhosis and low MELD scores who are at high risk for early death

Despite the adoption of "sickest first" liver transplantation, pretransplant death remains common, and many early deaths occur despite initially low Model for End-stage Liver Disease (MELD) scores. From 1997-2003, we studied 507 cirrhotic United States veterans referred for consideration of liver transplantation to identify additional predictors of early mortality. Most of the patients were male (98%) with cirrhosis caused by hepatitis C and/or alcohol (88%). Data for 296 patients referred prior to February 27, 2002 (training group), were analyzed; findings were validated in 211 patients referred subsequently (validation group). In the training group, 61 patients (21%) died within 180 days without transplantation; their median initial MELD score was 21. MELD score, persistent ascites, and low serum sodium (<135 meq/L) were independent predictors of early mortality. In patients with a MELD score of less than 21, only low serum sodium and persistent ascites were independent predictors of mortality; for MELD scores above 21, only MELD was independently predictive. Prognostic significance of persistent ascites and low serum sodium for low MELD score patients was confirmed in the validation group. Risk varied continuously with worsening hyponatremia. Modifying MELD, by including points for persistent ascites and low serum sodium, improved prediction of early pretransplant mortality in low MELD score patients. In conclusion, persistent ascites and low serum sodium identify patients with cirrhosis with high mortality risk despite low MELD scores. Ascites, hyponatremia, and other findings indicative of hemodynamic decompensation merit further prospective study as prognostic indicators in patients awaiting liver transplantation, and should be considered in setting minimal listing criteria.

Persistent ascites and low serum sodium identify patients with cirrhosis and low MELD scores who are at high risk for early death

Despite the adoption of "sickest first" liver transplantation, pretransplant death remains common, and many early deaths occur despite initially low Model for End-stage Liver Disease (MELD) scores. From 1997-2003, we studied 507 cirrhotic United States veterans referred for consideration of liver transplantation to identify additional predictors of early mortality. Most of the patients were male (98%) with cirrhosis caused by hepatitis C and/or alcohol (88%). Data for 296 patients referred prior to February 27, 2002 (training group), were analyzed; findings were validated in 211 patients referred subsequently (validation group). In the training group, 61 patients (21%) died within 180 days without transplantation; their median initial MELD score was 21. MELD score, persistent ascites, and low serum sodium (<135 meq/L) were independent predictors of early mortality. In patients with a MELD score of less than 21, only low serum sodium and persistent ascites were independent predictors of mortality; for MELD scores above 21, only MELD was independently predictive. Prognostic significance of persistent ascites and low serum sodium for low MELD score patients was confirmed in the validation group. Risk varied continuously with worsening hyponatremia. Modifying MELD, by including points for persistent ascites and low serum sodium, improved prediction of early pretransplant mortality in low MELD score patients. In conclusion, persistent ascites and low serum sodium identify patients with cirrhosis with high mortality risk despite low MELD scores. Ascites, hyponatremia, and other findings indicative of hemodynamic decompensation merit further prospective study as prognostic indicators in patients awaiting liver transplantation, and should be considered in setting minimal listing criteria.

Organ allocation: model for end-stage liver disease, Child-Turcotte-Pugh, Mayo risk score, or something else

The discovery of a single test of liver function has been a goal of hepatologists for many years. The great complexity of the liver and its many diverse functions, however, has prevented such an accomplishment. An analogy can be made with the way one currently uses liver tests where several individual tests are combined into a profile. This article presents evidence that confirms the same concept: Only by combining several clinical and laboratory measures can we predict the prognosis of liver disease patients. End-stage liver disease and pediatric end-stage liver disease models are valuable additions to the prognostic armamentarium; however, these models are not perfect and some important indications for liver transplant today cannot be included because their main issue is not disease severity.

Update on ascites and hepatorenal syndrome

Ascites is the most common complication occurring during liver cirrhosis. Even if a significant decrease in renal clearance may be observed in the first step of chronic active liver disease, renal impairment, at times complicated by the typical signs of hepatorenal syndrome, occurs only in patients with ascites, especially when tense and refractory. Experimental and clinical data seem to suggest a primary sodium and water retention in the pathogenesis of ascites, in the presence of an intrahepatic increase of hydrostatic pressure, which, by itself, physiologically occurs during digestion. Abnormal sodium and water handling leads to plasma volume expansion, followed by decreased peripheral vascular resistance and increased cardiac output. This second step is in agreement with the peripheral arterial vasodilation hypothesis, depicted by an increase in total blood volume, but with a decreased effective arterial blood volume. This discrepancy leads to the activation of the sympathetic nervous and renin-angiotensin-aldosterone systems associated with the progressive activation of the renal autacoid systems, especially, that of the arachidonic acid. During advanced cirrhosis, renal impairment becomes more sustained and renal autacoid vasodilating substances are less available, possibly due to a progressive exhaustion of these systems. At the same time ascites becomes refractory inasmuch as it is no longer responsive to diuretic treatment. Various pathogenetic mechanisms leading to refractory ascites are mentioned. Finally, several treatment approaches to overcome the reduced effectiveness of diuretic therapy are cited. Paracentesis, together with simultaneous administration of human albumin or other plasma expanders is the main common approach to treat refractory ascites and to avoid a further decrease in renal failure. Other effective tools are: administration of terlipressin together with albumin, implantation of the Le Veen shunt, surgical porto-systemic shunting or transjugular intrahepatic portosystemic stent-shunt, or orthotopic liver transplantation, according to the conditions of the individual patient.

Lack of prognostic usefulness of hepatic venous pressures and hemodynamic values in a select group of patients with severe alcoholic cirrhosis

OBJECTIVE

Prognostic assessment of patients with alcoholic cirrhosis is still controversial. A prospective study was performed to evaluate hemodynamic values as prognostic factors of death in a group of patients with severe alcoholic cirrhosis.

METHODS

From January, 1991 to February, 1993, a total of 87 admitted patients were prospectively studied. Measurements of the hepatic venous pressure gradient and cardiac output were performed in all patients. The mean follow-up was 35 months (range 1-76 months).

RESULTS

During this period, 56 patients (63% at 5 yr) died. The hepatic venous pressure gradient and cardiac output were not significantly different between the two groups. Using univariate analysis, only age and bilirubin concentration were different between those patients who lived and those who died. Cox regression analysis showed that age, encephalopathy, bilirubin concentration. prothrombin time, and Child-Pugh score were the only prognostic factors.

CONCLUSION

Measurement of the hepatic venous pressure gradient is not helpful in the prognostic assessment in a select group of patients with severe alcoholic cirrhosis.

Fluid and electrolyte abnormalities

Patients with cancer are at risk for developing a variety of fluid and electrolyte disturbances caused by the disease process or by complications from therapy. An understanding of the pathophysiology of these potential abnormalities allows the clinician to manage patients expectantly and to avoid severe metabolic disarray by correcting imbalances promptly.

[Renal Doppler ultrasonography and its relationship with the renal function in patients with liver cirrhosis]

BACKGROUND

To relate the renal hemodynamic changes, as assessed by Doppler ultrasonography,with the development of ascites, renal function, and endogenous vasoactive systems in patients with liver cirrhosis.

PATIENTS AND METHODS

60 cirrhotic patients were studied prospectively, 31 of these compensated and 29 with ascites. The renal resistive index, renal function and plasmatic levels of renin, aldosterone, noradrenaline and ADH activity were determined.

RESULTS

The renal resistive index was significantly higher in the cirrhotic patients with ascites (0.68) than in the compensated cirrhotics (0.63) and was significantly correlated with the serum levels of creatinine,urinary excretion of sodium, plasmatic renin activity and plasmatic concentration of aldosterone.

CONCLUSIONS

The renal resistive index, study by means of Doppler ultrasonography, shows progressively increased levels with the evolution of the disease, with the deterioration of the renal function and with the activation of the endogenous vasoactive systems.

A prognostic model for predicting survival in cirrhosis with ascites

BACKGROUND/AIMS

Parameters evaluating renal function and systemic hemodynamics are of prognostic significance in cirrhosis with ascites but are rarely used in the evaluation of survival of these patients. The aim of the current study was to develop a prognostic model to estimate survival of patients with cirrhosis and ascites.

METHODS

216 Cirrhotic patients admitted to hospital for the treatment of ascites were evaluated. Thirty-two demographic, clinical and laboratory variables, including parameters assessing liver and renal function and systemic hemodynamics, were analyzed as predictive factors of survival by using a Cox regression model.

RESULTS

Four variables had independent prognostic value: renal water excretion, as assessed by measuring diuresis after water load, mean arterial pressure, Child-Pugh class, and serum creatinine. According to these features a prognostic index was calculated that allows to estimate survival in patients with cirrhosis and ascites. The model accurately predicted survival in an independent series of 84 patients with cirrhosis and ascites.

CONCLUSION

A prognostic model that uses four easily available variables and predicts prognosis in cirrhotic patients with ascites has been developed. This model may be useful in the evaluation of patients with ascites for liver transplantation.

Pathophysiology and management of renal insufficiency in the perioperative and critically ill patient

Acute renal failure remains a common, devastating complication of the postoperative period and in the critically ill patient. The most common cause is the progression of prerenal insufficiency to ATN. Despite improved understanding of the pathogenic mechanisms, including impaired hemodynamic autoregulation, medullary hypoxia, and proximal tubular obstruction and transtubular backleak, the treatment, to date, remains largely supportive. Avoidance by ensuring hemodynamic stability, with provision of adequate renal perfusion, provides the best means for minimizing the complications of this organ dysfunction.

Portal hypertension induces sodium channel expression in colonocytes from the distal colon of the rat

Cellular mechanisms for Na(+) retention in portal hypertension are undefined, but epithelial Na(+) channels (ENaC) may be involved. Under high-salt diet, ENaC are absent from distal colon of rat but can be induced by mineralocorticoids such as aldosterone. Presence of rat ENaC was determined by amiloride inhibition of (22)Na(+) uptake in surface colonocytes 7 and 14 days after partial portal vein ligation (PVL) or sham surgery. At both times, uptake inhibition was significantly increased in PVL rats. Presence of mRNA transcripts, determined by RT-PCR, demonstrated that channel alpha- and gamma-subunits were similarly expressed in both groups but that beta-subunit mRNA was increased in PVL rats. This confirms that there was induction of rat ENaC and indicates that beta-subunit has a regulatory role. Urinary Na(+) was decreased for 3 days after PVL but was not different at other times, and serum aldosterone levels were elevated at 7 days, at a time when urinary Na(+) output was similar to that of sham-operated rats. We conclude that PVL leads to induction of ENaC in rat distal colon. An increase in aldosterone levels may prevent natiuresis and is probably one of several control mechanisms involved in Na(+) retention in portal hypertension.

Early effects of total paracentesis and albumin infusion on muscle sympathetic nerve activity in cirrhotic patients with tense ascites

BACKGROUND/AIMS

Cirrhotic patients with ascites are characterized by a marked activation of the sympathetic and the renin-angiotensin-aldosterone system. Total paracentesis is associated with a short-lived suppression of the renin-angiotensin-aldosterone system. Little information exists as to whether this favourable effect is parallelled by sympathoinhibition.

METHODS

In 16 Child C cirrhotic patients (age: 57.1+/-6.2 years, mean+/-SEM) with tense ascites we assessed the time course of the effects of total paracentesis followed by intravenous albumin (6-8 g/l of ascites) on beat-to-beat mean arterial pressure (Finapres), heart rate, plasma norepinephrine, epinephrine (high performance liquid chromatography) and muscle sympathetic nerve activity (microneurography, peroneal nerve). Measurements were obtained under baseline conditions, during staged removal of ascitic fluid (250 ml/min) and 24 h later. The patient remained supine throughout the study period.

RESULTS

Total paracentesis (10.6+/-1.3 l) induced a decrease in mean arterial pressure (from 95.0+/-2.6 mmHg to 88.2+/-3.2 mmHg, p<0.01), in heart rate (from 82.5+/-3.3 beats/min to 77.1+/-2.8 beats/min, p<0.01) and a reduction in plasma norepinephrine values (from 782+/-133 pg/ml to 624+/-103 pg/ml, p<0.01), which were substantially maintained 24 h later. In eight patients muscle sympathetic nerve activity did not change during paracentesis (from 65+/-7.1 bursts/min to 65+/-7.4 bursts/min, p=NS), but a marked reduction was observed 24 h later (48.4+/-5.6 bursts/min, p<0.01).

CONCLUSIONS

These data provide the first evidence that total paracentesis exerts an acute marked sympathoinhibitory effect. Whether this is a long-lasting phenomenon and to what extent plasma expansion with albumin contributes to this effects need to be further addressed.

Management of ascites in cirrhosis

Ascites is one of the earliest and most common complications of patients with cirrhosis. A typical circulatory dysfunction characterized by arterial vasodilation, high cardiac output and stimulation of vasoactive systems is commonly present in these patients and is associated with a poor prognosis. The treatment of ascites has been based on the combination of a low-sodium diet and the administration of diuretics. The reintroduction of paracentesis and the recent introduction of the transjugular intrahepatic portosystemic shunt (TIPS) are the most relevant innovations in the treatment of ascites during the past two decades, although controlled trials in large series of patients are needed to delineate whether TIPS is a safe and useful treatment for these patients.

Diagnosis of functional kidney failure of cirrhosis with Doppler sonography: prognostic value of resistive index

Time-velocity wave-form analysis of Doppler signals from small intrarenal arteries allows estimation of intrarenal arteriolar vascular resistance. Among the various indexes proposed, the resistive index is the most widely used for this estimation. To investigate whether the resistive index is useful in the diagnosis of functional kidney failure and prediction of survival in cirrhotic patients with ascites, we measured resistive index, kidney and liver function and plasma levels of renin, aldosterone and antidiuretic hormone in 10 healthy subjects, 12 patients with compensated cirrhosis and 32 patients with cirrhosis and ascites (17 with kidney failure). A total of 28 clinical and laboratory variables were analyzed for prognostic value. Resistive index was significantly increased in patients with kidney failure (0.74 +/- 0.01) compared with those in the other three groups (0.64 +/- 0.01, 0.64 +/- 0.02 and 0.67 +/- 0.01) and correlated significantly with glomerular filtration rate, arterial pressure, plasma renin activity and free water clearance in the cirrhotic patients. The sensitivity and specificity of the resistive index in detecting kidney failure in patients with ascites were 71% and 80%, respectively. Nine variables were correlated with survival in the univariate analysis, including resistive index, age, hepatomegaly, blood urea nitrogen, serum creatinine, plasma sodium concentration, glomerular filtration rate, plasma renin activity and plasma concentration of antidiuretic hormone. Multivariate analysis disclosed only three independent predictors of survival: plasma renin activity, plasma concentration of antidiuretic hormone and serum sodium concentration. In conclusion, resistive index is a sensitive method to assess intrarenal hemodynamics in patients with cirrhosis and ascites. It also has predictive value for survival in these patients.

Portal pressure, renal function and hormonal profile after acute and chronic captopril treatment in cirrhosis

The acute effects of captopril in cirrhosis are well known but there are few descriptions of the pattern of response to chronic administration of captopril in this disease. Nine nonuraemic cirrhotic patients with ascites and portal hypertension were studied after 1 week on fixed sodium and water intake (balance diet) and following acute and chronic treatment with captopril (three doses of 25 mg every 30 min and 75 mg.day-1 for three weeks, respectively). Whilst on the balance diet, 7/9 patients were unable to excrete the amount of sodium ingested. After the acute administration of captopril, a significant reduction was seen in arterial blood pressure (86.9 vs 77 mm Hg), with no change in the intra-hepatic pressures (free suprahepatic pressure, FSHP: 15.0 vs 12.1 mm Hg and wedged suprahepatic pressure, WSHP: 22.9 vs 20.7 mm Hg). After chronic captopril treatment, a drop was observed in portal pressure (FSHP: 9.4 mm Hg and WSHP 18.8 mm Hg, NS) and the arterial pressure returned to its basal level. The plasma aldosterone concentration decreased, whilst noradrenaline and dopamine increased significantly, the latter more than the former, leading to a reduction in the noradrenaline/dopamine ratio (14.5 vs 5.0). Seven out of nine patients showed enhanced natriuresis and the remaining two, who previously had had a positive sodium balance failed to do so. These haemodynamic, hormonal and renal changes were interpreted as evidence of blockade of angiotensin II generation by captopril, and also as a homoeostatic response by the sympathetic nervous system.

Assessment of the renin-angiotensin system in cirrhotic patients. Comparison between plasma renin activity and direct measurement of immunoreactive renin

The renin-angiotensin system plays an important physiological role and has prognostic significance in cirrhotics with ascites. The degree of stimulation of this system is usually estimated by measuring plasma renin activity after incubation periods of 2-3 h. Recent investigations showed that the direct measurement of immunoreactive renin also estimates the degree of activity of the system. In this study, immunoreactive renin and plasma renin activity (measured at incubation periods of 10, 20, 50 and 180 min) were determined in ten healthy subjects, five hyperreninemic non-hepatic patients and 47 cirrhotics with ascites. Cirrhotic patients showed significantly higher plasma renin activity (5.1 +/- 0.9 ng/ml per h, p less than 0.05) and immunoreactive renin (145.4 +/- 24.4 pg/ml, p less than 0.01) than healthy subjects (1.2 +/- 0.15 ng/ml per h and 25.1 +/- 1.1 pg/ml, respectively). The angiotensin I generation rate was constant during the 3-h incubation in 22 cirrhotics and a close relationship (r = 0.956, p less than 0.001) between plasma renin activity (3.5 +/- 1.6 ng/ml per h) and immunoreactive renin (71 +/- 25 pg/ml) was observed in these patients. In the remaining 25 cirrhotics the generation rate of angiotensin I declined with time and the calculated plasma renin activity at 180 min was lower than the activity calculated at 10 min by 50.7%.(ABSTRACT TRUNCATED AT 250 WORDS)