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At least 163 records · Page 9Linked to original sources
PubMed1983

Effect of dietary protein manipulation in subclinical portal-systemic encephalopathy.

Eight stable cirrhotic patients with mild or subclinical portal-systemic encephalopathy (PSE) were studied after shunt surgery when they were off all antiencephalopathic therapy. Equal amounts of mixed proteins were alternated with animal or vegetable protein in a crossover protocol under metabolic conditions for five consecutive, one week periods. The different dietary periods were not associated with either a change in the neurological impairment score or the Trailmaking Tests, which showed a learning effect. The peak frequencies of the computer analysed EEG (CAEEG) were lower during the animal (6.58 +/- 0.42 Hz) than the vegetable (7.10 +/- 0.44 Hz) diet (p 0.01). Neither arterial ammonia levels nor plasma amino acid ratios changed with the diets, whereas urinary 3-methyl-histidine excretion increased during the animal diet. During the vegetable diet the apparent nitrogen balance tended to be more positive than during either the mixed or animal diets associated with decrease in the urinary nitrogen excretion. The peak frequency of the CAEEG is the most sensitive test to monitor methods of treatment in portal-systemic encephalopathy. A vegetable protein diet, rather than overall protein restriction, should be considered in the management of this disorder, particularly when the nutritional state is poor.

Adult↗
PubMed1989

Successful long-term treatment of portal-systemic encephalopathy by the benzodiazepine antagonist flumazenil.

A patient with portal-systemic encephalopathy refractory to standard therapy (40-g protein diet, oral neomycin and lactulose, supplementation of diet with branched chain amino acids) following extensive liver resection and construction of a portacaval shunt was treated with 25 mg of flumazenil twice daily by mouth. Before treatment with flumazenil she was encephalopathic and experienced 12 attacks of coma within 2 yr. When treated with flumazenil all signs of encephalopathy abated in spite of an unrestricted dietary intake of protein. Two days after discontinuation of flumazenil treatment she became comatose again. She remained chronically encephalopathic and had four further episodes of coma during the subsequent 3 mo. Since reinstitution of flumazenil treatment she has been well for 14 mo during follow-up without any signs of encephalopathy while on an unrestricted protein diet. Furthermore, flumazenil therapy reversed abnormalities of recordings of multimodality evoked potentials that were associated with hepatic encephalopathy. The striking remission of encephalopathy by treatment with flumazenil suggests that this benzodiazepine antagonist may be valuable in the long-term management of portal-systemic encephalopathy.

Adult↗
PubMedDate not supplied

Evaluation of extrahepatic portal hypertension and surgical portal systemic shunts by intravenous CT portography.

The purpose of this study was to evaluate the splenoportal (SP) axis and patency of portal systemic shunts in extrahepatic portal venous obstruction (EHO) by intravenous CT portography (CTP). Fifty-five patients of preshunt EHO, and 21 patients of postshunt (surgical portal systemic shunts) EHO, were subjected to intravenous CTP on a subsecond helical CT scanner. Thin, axial sections and three dimensional (3-D) reconstructions, including maximum intensity projection (MIP) and shaded surface display (SSD), were obtained. The findings were correlated with Color Doppler Flow Imaging (CDFI). In the EHO preshunt group, the site of the block demonstrated on CTP correlated with CDFI in 53 of 55 cases. In the postshunt group, shunt patency evaluation by CTP was in agreement with CDFI in 19 of 21 patients (8 patent; 13 blocked). Two patients in each group could not be evaluated on CDFI, while CTP could provide the appropriate information. There was no false positivity or negativity with CTP in patients evaluated on both modalities. The etiology of EHO, the global view of collaterals, and the 3-D anatomy of SP axis could be well depicted and was well accepted by the surgeons. We conclude that CTP is an impressive new technique that can effectively evaluate pre- and postshunt cases of EHO.

Adult↗
PubMed1989

[Measurement of blood flow of the portal system in liver cirrhosis using the Doppler method].

Portal and splenchnic blood flow was studied in a group of 31 patients with hepatic cirrhosis and splenic veins. The authors used Acuson 128 with sector head 3,5 MHz enabling a simultaneous Doppler examination by means of impulse wave. A control group consisted of 50 healthy volunteers. Two patients had regressive flux in the portal vein, one patient had a reflux in the splenic vein. It was found that portal blood flow was significantly lower in the group examined than in the control group, and the splenic one was significantly higher. The sensitivity and specificity of the method of measuring the blood flow in the portal vein was 80%, and 88.2% respectively. 67.7% of patients had a different shape of the Doppler spectrum in the portal vein. That spectrum did not show the normally seen waves due to the heart beats. The authors' examinations show that the measurement of blood flow in the portal and splenic veins by means of the method using Doppler phenomenon provides valuable information on the haemodynamics of the portal system.

Adult↗
PubMed1996

[Lactilol (Importal, 10g in powder made by ZYMA) in the treatment of portal systemic encephalopathy].

In a group of 15 patients with portal systemic encephalopathy (PSE) associated with cirrhosis of the liver with portal hypertension and spontaneous systemic shunt of the portal circulation the authors administered Lactitol (Importal, powder à 10 g Zyma), in amounts up to 40 g/day for a period of 56 days. In the course of treatment every patient was repeatedly examined before the onset of treatment and three times during treatment. The grade of PSE was assessed on the basis of the score of the neuropsychiatric examination from which the PSE index was worked out. In the investigated group of patients with PSE the authors found a significant improvement of the PSE index during treatment with Importal Zyma. The mental condition of the patients improved, the NCT period was reduced, asterixis receded, on the EEG the delta and theta activity receded and normal alpha activity developed. The serum ammonia levels declined but did not reach statistical significance. During treatment the authors did not record changes of normal values of glucose, sodium and potassium in serum and did not detect any adverse side effects. Based on the assembled results the authors conclude that lactitol treatment extends possibilities of PSE treatment.

Adult↗
PubMed2004

Spontaneous intrahepatic portal-systemic venous shunt in the adult: case report and review of the literature.

Intrahepatic portal-systemic venous shunt is defined as a communication between the portal and the systemic-venous circulation, measuring more than 1 mm in diameter and at least partially located inside the liver. This is a rare condition, and the etiopathogenesis is unclear. Of the various types, Type I, with patent paraumbilical veins, located in the liver, is commonly encountered in portal hypertension. Other types are much less common. Only 47 cases have been reported in the entire French and English literature. Shunts may be congenital or acquired. This report describes a case of portal-systemic encephalopathy due to a spontaneous large-caliber portal-hepatic venous shunt in the right lobe of the liver confirmed by percutaneous transhepatic portography and hepatic venous angiogram. The treatment with coil embolization was successful, and hepatic encephalopathy resolved postoperatively with normalization of ammonia level. The etiology of the shunt was unclear. Given the age of the patient, the shunt was thought to have developed spontaneously.

Aged↗
PubMed1988

Model for the study of portal-systemic collateral vascular resistance in the conscious rat.

In order to obtain a model for the study of portal-systemic collateral vascular resistance, total portal vein occlusion was performed in rats 48 hr or 3 wk after partial obstruction. Four groups of conscious restrained rats were studied: a) sham-operated, b) partial portal vein ligated, c) 48 hr-total portal vein occluded, and d) 3 wk-total portal vein occluded. In comparison with the sham group, the three portal vein ligated groups had significantly higher cardiac output, portal tributary blood flow, portal pressure (7.7 +/- 0.4 versus 13.5 +/- 0.5, 13.6 +/- 0.8, and 17.7 +/- 1.1 mmHg, mean +/- SE, respectively) and hepatic arterial blood flow (5.8 +/- 0.6 versus 9.5 +/- 0.7, 8.3 +/- 0.5, and 13.9 +/- 1.9 ml/min, respectively). Cardiac output and portal tributary blood flow did not differ between the portal vein ligated groups, but portal pressure and hepatic arterial blood flow were significantly higher in the 3 wk-total portal vein occlusion group. The 3 wk-total portal vein occlusion group showed 99.1 +/- 0.3% shunting, different from the partial (29.7 +/- 16.9%, p less than 0.01) and 48 hr-total portal vein occlusion (46.5 +/- 14.7%, p less than 0.05) groups. Portography confirmed absence of portal-portal collaterals in the 3 wk-total portal vein occlusion group. It is suggested that rats with 3 wk-total portal vein occlusion are useful for the study of acute modifications of portal-systemic collateral circulation, as shunting is total and consistent in this model.

Animals↗
PubMed1982

Noninvasive assessment of portal-systemic shunting: evaluation of a method to investigate systemic availability of oral glyceryl trinitrate by digital plethysmography.

The systemic availability of oral glyceryl trinitrate may be a measure of the fraction of portal blood bypassing the hepatocytes through portal-systemic shunts. In order to test this hypothesis without the need for blood sampling, measurements of drug concentrations in plasma were replaced by assessments of pharmacologic effects by using digital plethysmography. Dose-response curves resulting from graded intravenous infusions of glyceryl trinitrate (8 and 25 microgram/min) were used as standard of comparison for the pharmacologic response resulting from an oral dose of 800 microgram. In 9 normal volunteers, systemic availability of oral glyceryl trinitrate was 2 +/- 4% SD. In 7 patients with end-to-side portacaval shunts it was 94 +/- 18%, in 3 patients with distal splenorenal shunts 57 +/- 11%, and in 10 patients with cirrhosis of the liver it varied between 15% and 85%. Systemic availability of glyceryl trinitrate was negatively correlated with the initial plasma disappearance rate of sulfobromophthalein (r = -0.72, p less than 0.01). No significant correlation was found with the galactose elimination capacity (r = -0.12, n = 17). The lack of systemic availability of glyceryl trinitrate in healthy volunteers together with an availability close to 100% after end-to-side shunts is compatible with a very high hepatic extraction of the test compound by the normal liver, and with the idea that the systemic availability of of oral glyceryl trinitrate comes close to representing portal-systemic shunting. The procedure is rapid, essentially noninvasive, and well tolerated by patients.

Administration, Oral↗
PubMed1990

Taking the tension out of the portal system. An approach to the management of portal hypertension in the 1990s.

The past decade saw the emergence of sclerotherapy and vasoactive pharmacologic agents as alternatives to surgery in the prevention and treatment of variceal haemorrhage. Despite encouraging results from clinical trials with regard to the prevention of rebleeding, these modalities of therapy have made no major impact on survival. This failure to alter radically the clinical outcome results from the fact that in many patients with cirrhosis death is primarily related to the degree of hepatic decompensation rather than the prevention or control of variceal bleeding. Advances in our knowledge of vasoactive mediators, receptor function, and altered vascular reactivity have provided increased insight into the circulatory disturbances that characterise cirrhosis and portal hypertension. Earlier and more aggressive pharmacologic intervention with single or combination drug therapy may inhibit fibrogenesis, reduce portal vascular resistance, and improve liver function and therefore provide effective prophylaxis against variceal haemorrhage. The emergence of reliable prognostic indices for variceal bleeding should help identify patients at risk who would benefit from prophylaxis with either drugs or sclerotherapy. Transplantation will be increasingly considered in the patient at high risk of recurrent bleeding before the stage of severe hepatic decompensation (the risks of the transplant then become very much greater), as the definitive means for reducing mortality in cirrhosis and portal hypertension.

Adrenergic beta-Antagonists↗
PubMed1975

Effect of hypokinesia and the combined action of gravitational load and hypokinesia on the structure of the hepatic portal system.

General hypokinesia during 1--6 weeks resulted in dilatation of the interlobular veins. sinusoids and central veins. The sequence of alterations corresponded to terms of hypokinesia. After exposure to "gravitation stress--hypokinesia for 1--6 weeks" stagnation in the portal system of the liver was less than after exposure to hypokinesia alone, but unevenness of lumens in the interlobular veins and sinusoids was more pronounced. The foci of the vessel spasm were determined. The signs of stagnation in the system of the portal vein and unevenness of the width of all the links of the portal bed were most pronounced after combination "hypokinesia for 1--6 weeks-- gravitation stress".

Adaptation, Physiological↗
PubMed1986

Thallium scintigraphy in the evaluation of portal systemic shunting. The problem of rectal absorption.

Thallium-201 scintigraphy is an attractive method for studying the portal systemic shunting. However, the technique is sometimes hampered by a low rectal absorption. The present work shows that cirrhotic patients present a significantly lower activity in the regions of interest in relation to the low absorption of the tracer as compared with non-cirrhotic subjects (p less than 0.01). This study also demonstrates that the dilution of the tracer in a large volume cannot be envisaged in order to increase the surface contact and secondarily the absorption, because part of the tracer can reach the inferior vena cava via portal systemic communications in the lower part of the rectum. Oral administration of the thallium was also attempted but this route cannot be used in relation to its poor absorption and due to the difficulty in separating liver from intestinal activity. The study also shows that even in the case of low activity in the regions of interest, the interpretation of the test in cirrhotic patients is usually possible on the condition that the curves of radioactivity in the liver and cardiac areas are ascending. Using these criteria, only 6.7% of the tests were in fact not interpretable in this study.

Female↗
PubMed1976

Angiographic documentation of systemic-portal venous shunting as a cause of a liver scan ""hot spot'' in superior vena caval obstruction.

Four patients with superior vena caval obstruction were evaluated with contrast venography and radiocolloid liver scans to investigate systemic-portal venous shunting as a cause of a liver scan "hot spot". In two of the cases a hot spot due to systemic-portal venous shunting was documented by angiography. The venous anatomy and pathophysiology related to hot spot formation on the liver scan is discussed. To develop a liver scan hot spot it appears necessary to have considerable systemic-portal venous flow through anterior parietal and periumbilical venous channels.

Angiography↗
PubMed1997

Elevated brain 5-hydroxytryptophol levels in experimental portal-systemic encephalopathy.

Brain tissue levels of the two serotonin metabolites 5-hydroxytryptophol and 5-hydroxyindole-3-acetic acid (5-HIAA) were measured in porta-caval shunted rats, an in vivo model of portal-systemic encephalopathy. An intraperitoneal challenge of L-tryptophan (280 mg/kg body weight) to sham-operated rats was also instituted to increase the brain serotonin metabolism in these rats. The results revealed significant increases in 5-hydroxytryptophol (by 31% and 5-HIAA (by 87%) brain levels in porta-caval shunted rats as compared to sham-operated controls. The brain 5-hydroxytryptophol-to-5-HIAA ratio was lower in the porta-caval shunted rats. The 5-hydroxytryptophol levels in sham rats after the L-tryptophan challenge were intermediate between the porta-caval shunted and sham rats but not statistically significant for either group. These results suggest that increased brain 5-hydroxytryptophol levels might be associated with the pathogenesis of portal-systemic encephalopathy. Further, the elevated brain 5-hydroxytryptophol levels in experimental portal-systemic encephalopathy are probably a result of the increased brain serotonin metabolism prevailing in this condition rather than changes in the brain redox potential.

Animals↗
PubMed1983

Effects of intra- and extrahepatic portal systemic shunts on insulin metabolism.

To study the effects of intra- and extrahepatic portal-systemic shunts on insulin degradation, 11 patients with liver cirrhosis and 7 noncirrhotic patients with liver disease were studied with percutaneous transhepatic catheterization. Insulin levels in portal and peripheral blood were measured simultaneously for 1-2 hr after intravenous administration of glucose. The degrees of intra- and extrahepatic portal-systemic shunting were measured with this technique using 131I-macroaggregated albumin and 99mTc-macroaggregated albumin. The amount of insulin secreted and insulin degraded were assessed from the areas under blood concentration curves for portal and peripheral blood. Insulin degradation was significantly reduced in cirrhotics compared to noncirrhotics with liver disease, although there was no difference in the amount of insulin secreted between these two groups. It was also correlated significantly with the degree of intrahepatic shunting but not with the degree of extrahepatic shunting. These results suggest that intrahepatic shunting plays an important role in the reduction of insulin degradation in cirrhosis.

Glucose Tolerance Test↗
PubMed2000

Portal systemic encephalopathy presenting with dressing and constructional apraxia.

We report a case with portal systemic encephalopathy who presented with dressing and constructional apraxia and subtle weakness of the left hand. We initially suspected a cerebrovascular attack in the right cerebral hemisphere, but brain T1-weighted magnetic resonance (MR) imaging revealed high intensity in the basal ganglia and hyperammonemia was detected. We performed abdominal MR angiography, which visualized an intrahepatic portal systemic shunt. Cerebral blood flow, measured by xenon-enhanced computed tomography, was decreased in the bilateral, but more dominantly right-sided, parietal watershed regions. We speculate that these boundary territories might be susceptible to damage by toxic metabolites of hepatic encephalopathy.

Aged↗
PubMed2000

Effects of portal-systemic shunt following 90% partial hepatectomy in rats.

We studied the effects of portal-systemic shunt after massive hepatectomy. Male Wistar rats were divided into two groups: one group underwent laparotomy alone (C group) and in the other group a portal-systemic shunt was placed through laparotomy (S group). After 90% hepatectomy was performed, 3-day and 1-week survival rates and histopathology were examined, and hepatic hemodynamics during the early stage after hepatectomy were measured using dye-containing microspheres. The 3-day survival rate in the S group was significantly higher, and the 1-week survival rate was slightly higher, than those in C group. Sinusoidal dilation 7 days after hepatectomy in the S group was significantly milder than that in the C group. Fatty degeneration of hepatocytes in the S group was significantly milder than that in the C group. With respect to hepatic hemodynamics during the early stage after hepatectomy, the rate of shunt (26.3%) in the S group was significantly higher than that (9.5%) in the C group. Portal pressure, total hepatic blood flow, and total hepatic blood flow per gram of liver in the S group were significantly lower than those in the C group. These results suggest that approximately 26% shunt after 90% hepatectomy in rats increases the early survival rate and improves histological changes in surviving rats 7 days after resection.

Animals↗
PubMed1991

Plasma glucagon concentration in cirrhosis is related to liver function but not to portal-systemic shunting, systemic vascular resistance, or urinary sodium excretion.

We tested the hypothesis that increased plasma glucagon concentration resulting from portal-systemic shunting or liver dysfunction causes arterial vasodilation and thereby stimulates sodium retention in cirrhosis. Twenty-seven studies were performed in patients with alcoholic liver disease, 11 of whom had ascites. Liver function was quantitated as the elimination rate of antipyrine, caffeine, and stable isotopes of cholic acid administered both orally (2,2,4,4-2H) and intravenously (24-13C). Portal-systemic shunt fraction was calculated as the ratio of the intravenous and oral clearances of the isotopes of cholic acid. Cardiac output was measured by using Doppler echocardiography. Plasma glucagon concentration was increased in patients with ascites when compared with that in patients without ascites (474 +/- 180 pg/ml vs 245 +/- 120 pg/ml, p = 0.0007) but was unrelated to urinary sodium excretion, heart rate, mean arterial pressure, cardiac output, and systemic vascular resistance (r = -0.48, 0.35, -0.13, 0.18, and 0.22, respectively). Plasma glucagon concentration correlated with the half-lives of all model compounds (r = 0.58, p = 0.002; r = 0.62, p = 0.0008; r = 0.62, p = 0.001; and r = 0.64, p = 0.0005; for caffeine, antipyrine, oral and intravenous cholic acid, respectively) but not with shunt fraction (r = 0.14). Increased plasma glucagon concentration in cirrhosis is probably a result of diminished hepatic clearance. However, increased plasma concentration of glucagon does not appear to cause a hyperdynamic circulatory state or sodium retention.

Glucagon↗