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Query: UNIPROT:P61278 (
somatostatin
)
22,083
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The therapy of
portal hypertension
depends to a significant extent on its clinical manifestation. In cases of acute haemorrhage from oesophageal varices in patients with
portal hypertension
, the objective of the therapy is to stop the haemorrhage (endoscopically, or by compression by means of a balloon probe) and to decrease the pressure and the reflux within the portal vascular bed. Urgent sclerotisation under the simultanous pharmacologic decrease of
portal hypertension
is successful in 93-95%. There is an alternative procedure residing in introducing a balloon probe for several hours and subsequent repeated sclerotisation until a complete eradication of varices is achieved regarding the prevention of haemorrhage exacerbation. Urgent surgical solution is on the basis of the results of various investigated studies reserved for patients in whom endoscopic sclerotisation was not successful. Indication of surgical therapy must be also deliberated in candidates for liver transplantation, regarding the possible consequent technical problems after some types of interventions. Endoscopic sclerotisation of oesophageal varices is also an appropriate preparation for transplantation of the liver in patients with liver cirrhosis included into the transplantation programme. TIPS is a perspective new method in the therapy of
portal hypertension
of both, non-bleeding varices, as well as in other indications. It is also a certain intermediating link in therapy in some patients with liver cirrhosis on the waiting list of candidates for liver transplantation. Pharmacotherapy is a significant part of the
portal hypertension
therapy. It is appropriate to combine the endoscopic treatment with pharmacotherapy of
portal hypertension
in both, cases of acute haemorrhage, as well as in the prevention of haemorrhage exacerbation. In cases of acute haemorrhage, the combination of glypressin with nitroglycerin is justified, as well as the therapy by
somatostatin
. The prevention of haemorrhage exacerbations uses a whole series of vasoactive substances, especially nitrates, beta-blockers and ACE inhibitors. The prevention of the first bleeding includes the prophylactic therapy (endoscopic, pharmacologic, or surgical) recommended only in a selected group of patients under high risk of bleeding. The possible perspective option will reside especially in the combined pharmacological therapy, the fact of which will have to be proven in the future. (Fig. 1, Ref. 25.)
...
PMID:[Treatment of portal hypertension]. 958 83
Early detection of bleeding site by immediate endoscopy is the key of effective treatment in massive upper gastrointestinal (GI) bleeding. Upper GI endoscopy gives useful information about the risk, re-bleeding and mortality. Algorithm of treatment is also based on findings upon early endoscopy. Meta-analysis of prospective, randomized, multicenter clinical trials assessing H2-receptor antagonists and proton pump-inhibitors in the treatment of peptic ulcers suggest that these drugs cannot be justified for stopping bleeding or prevent re-bleeding. Other drugs, such as
somatostatin
, might be effective, but further studies are needed to prove their effectiveness. Both vasopressin and
somatostatin
are also successfully employed the treatment of bleeding related to
portal hypertension
, and a recent meta-analysis found significant benefit for beta-blockade in the prevention of recurrent bleeding. Although beta-blocker therapy does not improve survival, it reduces re-bleeding rate, therefore, it can be used as prophylactic therapy for esophageal varices. As for the treatment of erosions, none of the drugs currently employed are effective in reducing or preventing clinically significant bleeding.
...
PMID:[Possibilities of drug therapy of acute hemorrhage of the upper digestive system]. 967 6
The medical treatment of
portal hypertension
has experienced marked progress in the past decade due to the production of effective
portal hypertension
therapy. This has been possible because of the better understanding of the pathophysiological mechanisms leading to
portal hypertension
. A major step forward was the introduction of beta-blockers for the prevention of bleeding and rebleeding from gastroesophageal varices. Effective therapy requires the reduction of the hepatic venous pressure gradient (HVPG) to 12 mm Hg or below, or at least by 20% of baseline values. Unfortunately, this is only achieved in 1/3-1/2 of patients. The combination therapy associated with isosorbide-5-mononitrate and propranolol or nadolol administration enhances the fall in portal pressure and increases the number of patients in whom HVPG decreases more than 20% and below 12 mm Hg. Randomized trials (RCTs) support the fact that combination therapy is more effective than propranolol or nadolol alone and better than sclerotherapy. In the treatment of acute variceal bleeding, pharmalogical therapy offers the unique advantage of permitting the provision of specific therapy immediately after arrival to hospital, or even during transferral to hospital by ambulance, since it does not require sophisticated personnel. Terlipressin has proved to be effective and to decrease mortality from bleeding. RCTs have shown that this drug is as effective and safer than emergency sclerotherapy. Therapy should be maintained for five days to prevent early rebleeding.
Somatostatin
is probably as effective as terlipressin.
...
PMID:Medical treatment of portal hypertension. 970 38
Spontaneous bacterial peritonitis (SBP) and varices bleeding are the most dangerous complications of liver cirrhosis. Symptoms of SBP are often nonspecific. SBP is diagnosed in the presence of more than 250 granulocytes/ml ascites and/or positive ascites cultures. Antibiotic prophylactic therapy is indicated after the first episode of SBP or primarily if ascites proteins is low (< 10 g/l). The varices bleeding should by treated endoscopically. In case of bleeding portal venous pressure can be lowered by infusion of
somatostatin
or vasopressin long-active analogues. In long-term therapy of
portal hypertension
non-selective betablockers or nitrates are effective.
...
PMID:[Therapy of acute variceal hemorrhage and spontaneous bacterial peritonitis in liver cirrhosis]. 978 69
In healthy subjects octreotide is largely metabolised by the liver suggesting that the plasma half-life of the
somatostatin
analogue may be prolonged in patients with hepatic dysfunction. The aim of this study was therefore (a) to determine the pharmacokinetics of octreotide following its subcutaneous injection in 6 patients with cirrhosis and
portal hypertension
and (b) compare the magnitude and duration of the effects of intravenous administration of 250 micrograms
somatostatin
and 50 micrograms octreotide on corrected wedged hepatic venous pressure (WHVP) and to relate the findings to the plasma levels of the analogue 1 h after administration in 13 patients with cirrhosis and
portal hypertension
. Following subcutaneous administration of 50 micrograms octreotide the circulating half life (range 2.4 to 4.79 h) was prolonged whereas the clearance (range 2.101 to 4.775 L/h) was decreased compared to healthy controls. Intravenous bolus administration of 250 micrograms
somatostatin
or 50 micrograms octreotide resulted in a reduction in WHVP of approximately the same magnitude and duration despite appreciable quantities of the analogue in the blood 1 h after administration (1944 +/- 226 pg/ml). These results indicate that the circulating half-life of octreotide is prolonged in cirrhotics suggesting that the dosage regimens should be modified in such patients to avoid accumulation of the analogue in the blood which may result in undesirable side-effects or toxicity. Furthermore, since the magnitude and duration of the reduction in WHVP elicited by IV octreotide is similar to that observed with
somatostatin
, the analogue, like the native hormone, must be administered by continuous IV infusion to produce a sustained response and hence a therapeutic effect in the management of acute variceal bleeding.
...
PMID:Pharmacokinetics of octreotide in patients with cirrhosis and portal hypertension; relationship between the plasma levels of the analogue and the magnitude and duration of the reduction in corrected wedged hepatic venous pressure. 983 May 76
Bleeding oesophageal varices (BOV), resulting from
portal hypertension
, can prove fatal. Not only is it important to stop the initial bleeding, which may lead to hypovolaemic shock, but also to treat this condition in the longer term, and, consequently, the prevention of rebleeding needs to be addressed. This review highlights the current findings on the haemostatic drug, terlipressin, focusing particular attention on the potential for longer-term treatment strategies in the prevention of rebleeding. The efficacy of terlipressin in treating acute BOV, its low incidence of severe side-effects (comparable to those of
somatostatin
) and its favourable comparison with sclerotherapy in the prevention of early rebleeds, all indicate the potential for terlipressin administration to be extended to 5 days in the longer-term treatment of BOV. In addition, terlipressin administration, in conjunction with sclerotherapy, can significantly reduce the likelihood of rebleeding compared with sclerotherapy alone and further supports its potential use in the longer-term treatment of BOV.
...
PMID:Longer treatment with vasoactive drugs to prevent early variceal rebleeding in cirrhosis. 989 51
In the last decade, the knowledge of the pathogenesis of
portal hypertension
has increased dramatically. Indeed, apart from the well-known pathogenetic importance of structural factors, the role of vasoactive factors, which enhance the increase in intrahepatic resistance, has been highlighted. The two pathogenetic factors of
portal hypertension
are: the increase in portal outflow resistance and an increase in splanchnic blood flow, which worsens and maintains the increased pressure in the portal vein. The increase in portal inflow is part of the hyperdynamic circulatory syndrome, which is a haemodynamic characteristic of cirrhotic patients. In portal hypertensive patients, almost all the known vasoactive systems/substances are activated or increased and the most recent studies have stressed the importance of the endothelial factors, such as endothelins, nitric oxide and prostaglandins. Knowledge of the haemodynamic mechanisms allows a pathogenetic approach to the treatment of
portal hypertension
, particularly as far as medical therapy is concerned. The main categories of drugs used are: the vasoconstrictors (i.e., vasopressin, glypressin,
somatostatin
, non-selective beta-blockers), which act by decreasing portal inflow, and the vasodilators (i.e., nitroderivatives), which act mainly by decreasing intrahepatic portal resistance. Moreover, technological developments have introduced new tools for diagnosis, such as echo-colour-Doppler, and therapy, like variceal banding and transjugular intrahepatic porto-systemic shunt.
...
PMID:Portal hypertension: state of the art. 1042 79
Recent advances in the knowledge of the pathophysiology of
portal hypertension
has opened new indications for the pharmacologic treatment of acute variceal bleeding. Treatment with vasoactive agents is immediately available, easy to use and can be considered as definitive or adjunctive to endoscopic therapy. The data from randomised trials of vasoactive drug treatment for acute variceal bleeding are reviewed, using meta-analysis where applicable. The use of vasopressin has been decreased as a consequence of its questionable efficacy and its high incidence of side effects. Terlipressin is the only drug that has been shown to improve survival, albeit in small trials and there are insufficient data of its use over 5 days.
Somatostatin
has been shown to have similar efficacy with terlipressin with significantly less side effects. The demonstrated efficacy of octreotide in acute variceal bleeding is less than terlipressin and
somatostatin
and it cannot be considered as drug of first choice.
Somatostatin
combined with sclerotherapy represents the optimal therapy today as this combination has been shown to be more effective than sclerotherapy alone and it is safe given over 5 days.
...
PMID:Role of vasoactive drugs in the treatment of bleeding oesophageal varices. 1056 86
Peripheral vasodilation initiates the hyperdynamic circulation in cirrhosis.
Somatostatin
and its analogues, such as octreotide, have a vasoconstrictive effect in cirrhotic patients and experimental animals with
portal hypertension
. The exact mechanism of octreotide-induced vasoconstriction remains unknown. To investigate whether octreotide produces vasoconstriction through suppression of vasodilatory peptides, such as glucagon, or through a local effect, we evaluated the effect of an intra-arterial dose on forearm blood flow (FBF), while measuring systemic glucagon levels. FBF was measured in 10 cirrhotic patients by venous occlusion plethysmography. The brachial artery of the nondominant arm was catheterized, and vasoactive drugs were administered: methacholine 4 microg/min; octreotide 20 microg/h, and octreotide 20 microg/h + methacholine 4 microg/min. Each infusion, lasting 5 minutes, was followed by saline for washout. FBF was measured in both arms during the last minute of each infusion and at the end of washout, with the uninfused arm acting as the control. Nitrates and nitrites, octreotide, and glucagon blood levels were determined at baseline and after each infusion. Percent change in flow (%triangle up) was obtained by comparing the flow during drug administration to that during the preceding saline infusion. Saline infusion did not alter FBF, but octreotide infusion resulted in a 34% +/- 7.7 (P <.005) reduction in FBF in the infused arm. FBF in the control arm was unchanged despite a significant decrease in systemic glucagon levels. Methacholine infusion increased FBF around 300%, which was not altered by the concomitant infusion of octreotide. Octreotide has a local vasoconstrictive effect that seems nitric oxide (NO)-independent. Octreotide probably has a facilitating effect over vasoconstrictors increased in chronic liver diseases.
...
PMID:Local arterial vasoconstriction induced by octreotide in patients with cirrhosis. 1070 44
Increased resistance to portal blood flow is the primary factor in the pathophysiology of
portal hypertension
, and is mainly determined by the morphological changes occurring in chronic liver diseases. This is aggravated by a dynamic component, due to the active-reversible- contraction of different elements of the porto-hepatic bed. A decreased synthesis of NO in the intrahepatic circulation is the main determinant of this dynamic component. This provides a rationale for the use of vasodilators to reduce intrahepatic resistance and portal pressure. Another factor contributing to aggravate the
portal hypertension
is a significant increase in portal blood flow, caused by arteriolar splanchnic vasodilation and hyperkinetic circulation. Splanchnic arteriolar vasodilation is a multifactorial phenomenon, which may involve local (endothelial) mechanisms as well as neurogenic and humoral pathways. Most pharmacological treatments have been aimed at correcting the increased portal blood inflow by the use of splanchnic vasoconstrictors, such as beta-blockers, vasopressin derivatives and
somatostatin
. Several studies have demonstrated that changes in the hepatic venous pressure gradient (HVPG) during maintenance therapy are useful to identify those patients who are going to have a variceal bleeding or rebleeding. The wide individual variation in the HVPG response to pharmacological treatment makes it desirable to schedule follow-up measurements of HVPG during pharmacological therapy. A priority for research in the forthcoming years is to develop accurate non-invasive methods to assess prognosis, which can be used to substitute or as surrogate indicators of the HVPG response. In the clinical management of
portal hypertension
, beta-blockers are at present the only accepted treatment for the prevention of variceal bleeding. Whether the association of isosorbide-5-mononitrate will improve the high efficacy of beta-blockers is questionable. The efficacy of more aggressive techniques, such as endoscopic band ligation, should be further tested against beta-blockers in patients with a high risk of bleeding. In the treatment of acute variceal bleeding, administration of
somatostatin
or terlipressin is an established therapy. It may be used alone or, preferably, as an initial treatment before sclerotherapy or endoscopic band ligation. No more than two sessions of endoscopic treatment should be used to control the bleeding. If the bleeding is not easily controlled, other alternatives such as transjugular intrahepatic portosystemic shunts (TIPS) or derivative surgery should be considered, the former being the best in patients with poor liver function. Recent studies suggest that early measurement of HVPG during variceal bleeding may be used as a guide for therapeutic decisions in the treatment of patients with acute variceal bleeding. Those patients with a high HVPG have a high risk of poor evolution, and may be candidates for more intensive and aggressive therapy, such as surgery or TIPS. Those with lower HVPG have a very high probability of an uneventful evolution, and may thus be managed more conservatively using medical and endoscopic treatments. Pharmacological agents (propranolol or nadolol), endoscopic treatment (preferably banding ligation) or surgery can be used to prevent rebleeding. A pending task for the new millennium is to assess whether the early treatment of asymptomatic, compensated cirrhotic patients with portal pressure reducing agents can prevent the development of esophageal varices and of other complications of
portal hypertension
.
...
PMID:Complications of cirrhosis. I. Portal hypertension. 1072 1
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