Effect of side to side portacaval shunt on intractable ascites, sodium excretion, and aldosterone metabolism in man

Renal dysfunction in cirrhosis: acute kidney injury and the hepatorenal syndrome

Renal dysfunction is a common complication of liver cirrhosis and of utmost clinical and prognostic relevance. Patients with cirrhosis are more prone to developing acute kidney injury (AKI) than the non-cirrhotic population. Pre-renal AKI, the hepatorenal syndrome type of AKI (HRS-AKI, formerly known as 'type 1') and acute tubular necrosis represent the most common causes of AKI in cirrhosis. Correct differentiation is imperative, as treatment differs substantially. While pre-renal AKI usually responds well to plasma volume expansion, HRS-AKI and ATN require different specific approaches and are associated with substantial mortality. Several paradigms, such as the threshold of 2.5 mg/dL for diagnosis of HRS-AKI, have recently been abolished and novel urinary biomarkers are being investigated in order to facilitate early and correct diagnosis and treatment of HRS-AKI and other forms of AKI in patients with cirrhosis. This review summarizes the current diagnostic criteria, as well as pathophysiologic and therapeutic concepts for AKI and HRS-AKI in cirrhosis.

Maintenance of hemodynamic response to treatment for portal hypertension and influence on complications of cirrhosis

BACKGROUND/AIMS

Following treatment with beta blockers in patients with cirrhosis and portal hypertension, reduction of hepatic venous pressure gradient (HVPG) to <12 mmHg or by >20% of baseline induces an extremely low risk of variceal bleeding. However, several factors such as compliance to therapy or alcohol abstinence may change the initial response after a long follow-up, and the effect of response on other complications of cirrhosis is less clear. The aim of this study was to assess the long-term maintenance of hemodynamic response and its influence on complications of cirrhosis.

METHODS

One hundred and thirty two cirrhotic patients received nadolol and isosorbide mononitrate to prevent variceal rebleeding. HVPG was measured at baseline, after 1 to 3 months under treatment and again 12 to 18 months later.

RESULTS

Sixty four patients were responders. After a longer follow-up, earlier response did not change in 81% of cases. Changes of response were mainly related to modifications in medication dose or in alcohol intake. As compared with poor-responders, responders had a lower probability of developing ascites (P<0.001) and related conditions, a greater improvement of Child-Pugh score (P=0.03), and a lower likelihood of developing encephalopathy (P=0.001) and of requiring liver transplantation (P=0.002). Eleven responders and 22 poor-responders died (P=0.029).

CONCLUSIONS

Hemodynamic response to treatment of portal hypertension is usually sustained after a long-term follow-up. Response decreases the probability of developing complications of cirrhosis and the need for liver transplantation, and significantly improves survival.

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.

The treatment of refractory ascites by the LeVeen shunt. A multi-centre controlled trial (57 patients)

A multi-centre random trial of 57 cases of alcoholic cirrhosis with refractory ascites was carried out; 29 patients received a LeVeen shunt and 28 were treated by conventional medical therapy. The effectiveness of the LeVeen shunt in reducing ascites was good in the first month, but was not different from conventional medical therapy by the end of one year. Complications were significantly more frequent in the surgical group. Of the 29 patients fitted with a LeVeen shunt, 25 developed one or more complications. Of the 28 patients in the medical control group, only 8 developed complications. The mortality rate of the two groups also differed significantly. Twelve patients in the surgical group (41%) died in the course of the first month against only 5 (18%) in the medical control group. By the end of one year, the mortality rate of the two groups was almost identical: 23 (79%) and 21 (75%) respectively. These observations confirm the poor prognosis for refractory ascites in cases of alcoholic cirrhosis and the inadvisability of attempting to treat it by implanting a LeVeen shunt.

Resistant ascites in alcoholic liver cirrhosis: course and prognosis

A group of 29 patients with decompensated cirrhosis of the liver who retained a large amount of ascites under a hospital regimen during two months or longer was identified. The prognosis for this selected group of patients, while grave [during continuous hospitalization 11 out of 29 patients (= 38%) died], is not without hope: 18 patients (62%) improved and could be discharged from the hospital. Their further course was influenced by resumption of alcohol usage. Five of 11 (45.4%) who resumed drinking died due to hepatic causes within 10 months. Of the remaining six only one lost his ascites. Those who abstained (7 patients) remained alive for an average follow-up of 33 months and all lost their ascites. Alcohol resumption significantly decreased both survival (P less than 0.05) and ascites resorption (P less than 0.0015). Continued abstinence from alcohol may thus obviate the need for surgical measures to relieve ascites in these patients.

Natriuretic hormone--its possible role in fluid and electrolyte disturbances in chronic liver disease

Besides intrarenal physical factors and aldosterone, a natriuretic hormone has been postulated to modulate renal tubular sodium resorption in order to maintain body fluid homeostasis. To investigate the possible role of a natriuretic activity in sodium retention of chronic liver disease, the effects of plasma and plasma fraction IV from patients with cirrhosis of the liver and ascites on sodium transport of the isolated frog skin and on renal sodium excretion in the rat were compared to the antinatriferic and natriuretic effects of plasma from healthy subjects. While plasma from healthy individuals obtained following acute expansion of the extracellular fluid volume (ECV) significantly inhibited potential difference (PD) by -43·8 ± 5·5% and short circuit current (SCC) by -41·3 ± 1·7% when applied to the inner skin surface, control plasma and plasma from patients with liver cirrhosis and ascites affected PD by -3·8 ± 4·7% and -5·2 ± 3·7% and SCC by -7·3 ± 4·6% and -11·7 ± 2·5% respectively.

Similar effects on PD and SCC were observed with plasma fractions IV.

In contrast to fraction IV from ECV-expanded individuals, which caused marked diuresis and natriuresis when injected in the rat, fraction IV of plasma from cirrhotic patients failed to affect urinary flow rate, free-water clearance or renal sodium excretion. The results suggest that at least some patients with cirrhosis of the liver and sodium retention may lack an adequate humoral natriuretic activity sufficiently to promote renal sodium excretion.

The hepatorenal syndrome: recovery after portacaval shunt

Reversal of the morbid hepato-renal syndrome has been achieved in a cirrhotic patient with ascites following successful side-to-side portacaval shunt. The hepatorenal syndrome is defined as progressive unresponsive renal failure with previously normal kidneys in the presence of impaired hepatic function. Although the etiologic mechanism has not been defined, it is suggested the relationship of increased intrahepatic sinusoidal pressure on the thoracic duct and subsequent decreased lymph flow are interrelated to increased levels of aldosterone and manifested by (chylous) ascites. Laboratory and clinical evidence suggest that cirrhotics with ascites have remarkably high levels of aldosterone secretion via the rennin-angiotensin-adrenal cortex mechanism. This is the group that develops hepatorenal syndrome. Reduction of the intrahepatic pressure and decompression of the portal hypertension can be successfully achieved with a side-to-side shunt which should return the aldosterone-rennin-angiotensin axis to normal and subsequently reverse the hepatorenal syndrome.

Portal decompression: clinical experience with the "H" graft

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