Controlled trial of vasopressin plus nitroglycerin vs. vasopressin alone in the treatment of bleeding esophageal varices

Treatment for bleeding oesophageal varices in people with decompensated liver cirrhosis: a network meta-analysis

BACKGROUND

Approximately 40% to 95% of people with liver cirrhosis have oesophageal varices. About 15% to 20% of oesophageal varices bleed within about one to three years after diagnosis. Several different treatments are available, including, among others, endoscopic sclerotherapy, variceal band ligation, somatostatin analogues, vasopressin analogues, and balloon tamponade. However, there is uncertainty surrounding the individual and relative benefits and harms of these treatments.

OBJECTIVES

To compare the benefits and harms of different initial treatments for variceal bleeding from oesophageal varices in adults with decompensated liver cirrhosis, through a network meta-analysis; and to generate rankings of the different treatments for acute bleeding oesophageal varices, according to their benefits and harms.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, Science Citation Index Expanded, World Health Organization International Clinical Trials Registry Platform, and trials registers until 17 December 2019, to identify randomised clinical trials (RCTs) in people with cirrhosis and acute bleeding from oesophageal varices.

SELECTION CRITERIA

We included only RCTs (irrespective of language, blinding, or status) in adults with cirrhosis and acutely bleeding oesophageal varices. We excluded RCTs in which participants had bleeding only from gastric varices, those who failed previous treatment (refractory bleeding), those in whom initial haemostasis was achieved before inclusion into the trial, and those who had previously undergone liver transplantation.

DATA COLLECTION AND ANALYSIS

We performed a network meta-analysis with OpenBUGS software, using Bayesian methods, and calculated the differences in treatments using odds ratios (OR) and rate ratios with 95% credible intervals (CrI) based on an available-case analysis, according to National Institute of Health and Care Excellence Decision Support Unit guidance. We performed also the direct comparisons from RCTs using the same codes and the same technical details.

MAIN RESULTS

We included a total of 52 RCTs (4580 participants) in the review. Forty-eight trials (4042 participants) were included in one or more comparisons in the review. The trials that provided the information included people with cirrhosis due to varied aetiologies and those with and without a previous history of bleeding. We included outcomes assessed up to six weeks. All trials were at high risk of bias. A total of 19 interventions were compared in the trials (sclerotherapy, somatostatin analogues, vasopressin analogues, sclerotherapy plus somatostatin analogues, variceal band ligation, balloon tamponade, somatostatin analogues plus variceal band ligation, nitrates plus vasopressin analogues, no active intervention, sclerotherapy plus variceal band ligation, balloon tamponade plus sclerotherapy, balloon tamponade plus somatostatin analogues, balloon tamponade plus vasopressin analogues, variceal band ligation plus vasopressin analogues, balloon tamponade plus nitrates plus vasopressin analogues, balloon tamponade plus variceal band ligation, portocaval shunt, sclerotherapy plus transjugular intrahepatic portosystemic shunt (TIPS), and sclerotherapy plus vasopressin analogues). We have reported the effect estimates for the primary and secondary outcomes when there was evidence of differences between the interventions against the reference treatment of sclerotherapy, but reported the other results of the primary and secondary outcomes versus the reference treatment of sclerotherapy without the effect estimates when there was no evidence of differences in order to provide a concise summary of the results. Overall, 15.8% of the trial participants who received the reference treatment of sclerotherapy (chosen because this was the commonest treatment compared in the trials) died during the follow-up periods, which ranged from three days to six weeks. Based on moderate-certainty evidence, somatostatin analogues alone had higher mortality than sclerotherapy (OR 1.57, 95% CrI 1.04 to 2.41; network estimate; direct comparison: 4 trials; 353 participants) and vasopressin analogues alone had higher mortality than sclerotherapy (OR 1.70, 95% CrI 1.13 to 2.62; network estimate; direct comparison: 2 trials; 438 participants). None of the trials reported health-related quality of life. Based on low-certainty evidence, a higher proportion of people receiving balloon tamponade plus sclerotherapy had more serious adverse events than those receiving only sclerotherapy (OR 4.23, 95% CrI 1.22 to 17.80; direct estimate; 1 RCT; 60 participants). Based on moderate-certainty evidence, people receiving vasopressin analogues alone and those receiving variceal band ligation had fewer adverse events than those receiving only sclerotherapy (rate ratio 0.59, 95% CrI 0.35 to 0.96; network estimate; direct comparison: 1 RCT; 219 participants; and rate ratio 0.40, 95% CrI 0.21 to 0.74; network estimate; direct comparison: 1 RCT; 77 participants; respectively). Based on low-certainty evidence, the proportion of people who developed symptomatic rebleed was smaller in people who received sclerotherapy plus somatostatin analogues than those receiving only sclerotherapy (OR 0.21, 95% CrI 0.03 to 0.94; direct estimate; 1 RCT; 105 participants). The evidence suggests considerable uncertainty about the effect of the interventions in the remaining comparisons where sclerotherapy was the control intervention.

AUTHORS' CONCLUSIONS

Based on moderate-certainty evidence, somatostatin analogues alone and vasopressin analogues alone (with supportive therapy) probably result in increased mortality, compared to endoscopic sclerotherapy. Based on moderate-certainty evidence, vasopressin analogues alone and band ligation alone probably result in fewer adverse events compared to endoscopic sclerotherapy. Based on low-certainty evidence, balloon tamponade plus sclerotherapy may result in large increases in serious adverse events compared to sclerotherapy. Based on low-certainty evidence, sclerotherapy plus somatostatin analogues may result in large decreases in symptomatic rebleed compared to sclerotherapy. In the remaining comparisons, the evidence indicates considerable uncertainty about the effects of the interventions, compared to sclerotherapy.

Gastrointestinal Issues in Liver Disease

Gastrointestinal (GI) complications of cirrhosis are frequent in patients who require intensive care support and are often the primary indication for intensive care unit (ICU) admission. Perhaps the most worrisome GI complication for the intensivist is variceal hemorrhage. Bleeding from esophageal or gastric varices represents a life-threatening event for cirrhotic patients and provides management challenges for the ICU team. Nonvariceal GI bleeding, impaired GI motility, and malnutrition also provide significant challenges for the intensivist. This article reviews GI issues that present in critically ill cirrhotic patients and their management in the acute setting.

Nonendoscopic management strategies for acute esophagogastric variceal bleeding

Acute variceal bleeding is a potentially life-threatening complication of portal hypertension. Management consists of emergent hemostasis, therapy directed at hemodynamic resuscitation, protection of the airway, and prevention and treatment of complications including prophylactic use of antibiotics. Endoscopic treatment remains the mainstay in the management of acute variceal bleeding in combination with pharmacotherapy aimed at reducing portal pressure. This article intends to highlight only the current nonendoscopic treatment approaches for control of acute variceal bleeding.

Medical management of variceal hemorrhage

Gastroesophageal variceal hemorrhage is a major complication of portal hypertension in 50% to 60% of patients with liver cirrhosis and is a frequent cause of mortality in these patients. The prevalence of variceal hemorrhage is approximately 5% to 15% yearly, and early variceal rebleeding has a rate of occurrence of 30% to 40% within the first 6 weeks. More than 50% of patients who survive after the first bleeding episode will experience recurrent bleeding within 1 year. Management of gastroesophageal varices should include prevention of initial and recurrent bleeding episodes and control of active hemorrhage. Therapies used in the management of gastroesophageal variceal hemorrhage may include pharmacologic therapy (vasoactive agents, nonselective b-blockers, and antibiotic prophylaxis), endoscopic therapy, transjugular intrahepatic portosystemic shunt, and shunt surgery. This article focuses primarily on pharmacologic management of acute variceal hemorrhage.

Management of acute esophageal variceal hemorrhage

Acute esophageal variceal hemorrhage (AEVH) is a severe complication of portal hypertension. Its management has rapidly evolved in recent years. Traditional methods included vasoconstrictor and balloon tamponade. Vasoconstrictors were shown to control approximately 80% of the bleeding episodes and are generally used as a first-line therapy. Following the use of vasoconstrictors, endoscopic therapy is often used to arrest the bleeding varices and prevent early rebleeding. A meta-analysis showed that the combination of vasoconstrictor and endoscopic therapy is superior to endoscopic therapy alone for controlling AEVH. Balloon tamponade may be used to achieve temporary control of the hemorrhage in case of severe bleeding. A transjugular intrahepatic portosystemic stent shunt may be needed in patients with refractory acute variceal hemorrhage. Surgical intervention is now widely contraindicated during acute variceal hemorrhage, except for patients with good liver reserve. Conversely, apart from the control of acute variceal hemorrhage, prophylactic antibiotics were shown to be helpful in the prevention of bacterial infection and to prevent early variceal rebleeding. With the introduction of new treatment modalities and the measures taken to manage patients with AEVH, the mortality due to AEVH has significantly decreased in recent years.

Portal hypertension and variceal hemorrhage

Portal hypertension is a progressively debilitating complication of cirrhosis and a principal cause of mortality in patients who have hepatic decompensation. This article describes the classification system and pathophysiology of portal hypertension. It also discusses a practical approach to prevention of first variceal hemorrhage, general management of the acute bleeding episode, and secondary prophylaxis to prevent rebleeding. Pharmacologic, endoscopic, radiologic, and surgical modalities are all described in detail.

Chronic thalidomide administration enhances vascular responsiveness to vasopressin in portal-systemic collaterals of bile duct-ligated rats

BACKGROUND

Arginine vasopressin (AVP) controls gastroesophageal variceal bleeding, partly due to its vasoconstrictive effect on portal-systemic collaterals. It has been shown that chronic thalidomide treatment decreases portal pressure, attenuates hyperdynamic circulation and inhibits vascular endothelial growth factor (VEGF) and tumor necrosis factor (TNF)-alpha in partially portal vein-ligated rats. This study investigated the effects of chronic thalidomide treatment on portal-systemic collateral vascular responsiveness to AVP in common bile duct-ligated (CBDL) cirrhotic rats.

METHODS

In the first series, CBDL-induced cirrhotic rats received thalidomide (50 mg/kg/day orally) or distilled water (control) from the 35th to 42nd day after ligation. On the 43rd day after ligation, the body weight, mean arterial pressure, portal pressure, and heart rate were measured. An in situ collateral vascular perfusion model was used to obtain the cumulative concentration-response curves of collateral vessels to AVP (10(-10) to 3 x 10(-7) M). Plasma levels of VEGF and TNF-alpha were measured, and expressions of VEGF and TNF-alpha mRNA in the left adrenal veins were also determined. In the second series, the cumulative concentration-response curves of collateral vessels to AVP in CBDL rats with or without thalidomide (10(-5) M) preincubation in the perfusate were obtained.

RESULTS

The thalidomide and control groups were not significantly different in terms of heart rate, mean arterial pressure and portal pressure (p > 0.05). The collateral vascular perfusion pressure change to AVP was significantly enhanced at 10(-8) M after thalidomide treatment (p = 0.041). Compared with the control group, thalidomide-treated rats had significantly lower plasma VEGF levels (p < 0.001), accompanied by an insignificant reduction in plasma TNF-alpha levels (p > 0.05). The expressions of VEGF and TNF-alpha mRNA in the left adrenal veins of thalidomide-treated CBDL rats were not significantly changed compared with those of the control group. In addition, thalidomide did not significantly elicit changes in vascular responsiveness to AVP in collateral vessels of CBDL rats when it was added into the perfusate.

CONCLUSION

In cirrhotic rats, chronic thalidomide treatment improves the portal-systemic collateral vascular responsiveness to AVP, which was partly related to VEGF inhibition.

Acute variceal hemorrhage

Variceal bleeding is a frequent and life-threatening complication of portal hypertension. The first episode of variceal bleeding is associated not only with a high mortality, but also with a high recurrence rate in those who survive. Therefore, management should focus on different therapeutic strategies aiming to prevent the first episode of variceal bleeding (primary prophylaxis), to control hemorrhage during the acute bleeding episode (emergency treatment), and to prevent rebleeding (secondary prophylaxis). These strategies involve pharmacological, endoscopic, surgical, and interventional radiological modalities. This article reviews management of acute variceal bleeding.

Emergency management of bleeding esophageal varices: drugs, bands or sleep?

Variceal bleeding is a severe complication of cirrhosis leading to significant morbidity and mortality. Treatment of acute variceal bleeding has improved dramatically since the era of the mechanical balloon tamponade. These advances include endoscopic band ligation or sclerotherapy, and vasoactive pharmacological options such as somatostatin, octreotide, vasopressin and terlipressin. Evidence from a multitude of clinical trials and meta-analyses comparing endoscopic and pharmacological treatments suggests near equivalence in efficacy for initial hemostasis, mortality and rate of rebleeding. This raises the question of whether on-call gastroenterologists should be performing emergency endoscopic treatment in the middle of the night or start pharmacological treatment and delay endoscopy until optimal patient and working conditions the next morning. The present review analyzes the available comparative data between endoscopic and pharmacological treatment options. Although the literature cannot yet definitively answer the question posed, the authors suggest that delaying endoscopic treatment until the next morning may be the most reasonable practical approach.

Endoscopic variceal ligation versus propranolol in prophylaxis of first variceal bleeding in patients with cirrhosis

BACKGROUND AND AIM

To compare the efficacy and safety of endoscopic variceal ligation (EVL) with propranolol in prophylaxis on the rate of first esophageal variceal bleeding in patients with cirrhosis.

METHODS

A prospective, randomized trial was conducted in 100 cirrhotic patients with no history of previous upper gastrointestinal bleeding and with esophageal varices endoscopically judged to be at high risk of hemorrhage. The end-points of the study were bleeding and death.

RESULTS

Life-table curves showed that prophylactic EVL and propranolol were similarly effective for primary prophylaxis of variceal bleeding (11/50 [22%]vs 12/50 [24%]; P = 0.68) and overall mortality (14/50 [28%]vs 12/50 [24%]; P = 0.49). The 2-year cumulative bleeding rate was 18% (9/50) in the EVL group and 16% (8/50) in the propranolol group. The 2-year cumulative mortality rate was 28% (14/50) in the EVL group and 24% (12/50) in the propranolol group. Comparison of Kaplan-Meier estimates of the time to death of both groups showed no significant difference in mortality in both groups (P = 0.86). Patients undergoing EVL had few treatment failures and died mainly of hepatic failure. In the propranolol group, the mean daily dosage of the drug was 68.2 +/- 32.8 mg, which was sufficient to reduce the pulse rate by 25%. 20% of patients withdrew from propranolol treatment due to adverse events.

CONCLUSIONS

Prophylaxis EVL is as effective and as safe as treatment with propranolol in decreasing the incidence of first variceal bleeding and death in cirrhotic patients with high-risk esophageal varices.

Bleeding caused by portal hypertension

Variceal bleeding is one of the dreaded complications of portal hypertension. Patients who have suspected or proven cirrhosis should undergo diagnostic upper endoscopy to detect medium and large gastro-esophageal varices. Patients with medium and large gastro-esophageal varices should be treated with non-selective beta-blockers (propranolol or nadolol), and these agents should be titrated to a heart rate of 55 beats per minute or adverse effects. If there are contraindications to or if patients are intolerant to beta-blockers, it is appropriate to consider prophylactic banding therapy for individuals with medium-to-large esophageal varices. When patients who have cirrhosis present with GI bleeding, they should be resuscitated and receive octreotide or other vasoactive agents. Endoscopy should be performed promptly to diagnose the source of bleeding and to provide endoscopic therapy (preferably banding). The currently available treatment for acute variceal bleeding provides hemostasis in most patients. These patients, however, are at significant risk for rebleeding unless secondary prophylaxis is provided. Although various pharmacological, endoscopic, radiological, and surgical options are available, combined pharmacological and endoscopic therapy is the most common form of secondary prophylaxis. TIPS is a radiologically placed portasystemic shunt, and if placed in suitable patients, it can provide effective treatment for patients with variceal bleeding that is refractory to medical and endoscopic therapy.

Transcatheter treatment for lower gastrointestinal hemorrhage

Modern transcatheter embolization has emerged as a viable option for the treatment of lower gastrointestinal (LGI) hemorrhage. Over the last decade, steady data has accumulated showing the safety and effectiveness of superselective microcoil embolization within the colon. In light of such results, the application of microcatheter-based skills has become more important in an algorithm for managing LGI bleeding. The purpose of this article is to discuss the modern embolization technique while also reviewing traditional and experimental transcatheter methods that may prove useful in the appropriate clinical settings. While recognizing that transcatheter therapy continues to evolve, the proposed indications for these current treatments are reviewed.

Review article: the management of acute variceal bleeding

Variceal haemorrhage is a common medical emergency with a high mortality (30-50%). Adequate resuscitation is vital, and once stabilised the patient should be moved to a high-dependency area. Antibiotics reduce mortality, and the vasoactive drug terlipressin should be administered if early endoscopy is unavailable. Early endoscopy is essential both to make the diagnosis and to allow therapeutic measures to be performed. The evidence suggests that variceal band ligation is the most effective therapy for oesophageal varices. If gastric varices are found at the index endoscopy the evidence at present is inadequate to be certain which is the best treatment, but both endoscopic therapy with cyanoacrylate or thrombin and transjugular intrahepatic portosystemic stent shunt (TIPSS) have been reported to be of benefit. When initial treatments fail, rescue therapy should be initiated. Most authorities agree that TIPSS is the rescue therapy of choice. Many questions remain concerning the treatment of acute variceal bleeding, particularly the ideal therapy for gastric varices and the role of combination vasoactive and endoscopic therapy. Randomised controlled trials are required to answer these important issues.

Effects of long-term octreotide treatment on the response of portal-systemic collaterals to vasopressin in portal hypertensive rats

BACKGROUND

Chronic portal hypertension is associated with the development of portal-systemic collaterals. Long-term octreotide treatment has been shown to enhance the constrictive response to vasopressin in the mesenteric arteries of portal hypertensive rats. This study investigated the effects of long-term octreotide treatment on the response of portal-systemic collaterals to vasopressin in portal hypertensive rats.

METHODS

Partially portal vein-ligated rats were divided into two groups to receive subcutaneous injection of either placebo (5% dextrose in water) or octreotide (30 microg kg(-1)) twice daily for 7 days. Two series of experiments were performed to measure: (a) the systemic and portal hemodynamics and cumulative concentration-response curves of collateral vessels to vasopressin (10(-10) to 10(-7 )M) and (b) the slopes of the flow-pressure curves of collaterals (an index of portal-systemic shunting). The cumulative concentration-response curves and flow pressure curves were determined by the in situ collateral perfusion.

RESULTS

Long-term octreotide treatment significantly lowered the portal pressure without changes in the mean arterial pressure. Vasopressin significantly and similarly increased the perfusion pressure of collateral vessels in both the placebo- and octreotide-treated groups. In addition, long-term octreotide treatment exerted no effect on the EC(50) of vasopressin (-8.25 +/- 0.19 vs. -8.20 +/- 0.10, P > 0.05) and the slopes of flow-pressure curves (0.97 +/- 0.02 vs. 0.94 +/- 0.04, P > 0.05) in the collaterals.

CONCLUSION

Despite lowering the portal pressure, long-term octreotide treatment did not enhance the vasoconstrictive effect of vasopressin in the collateral vessels of portal hypertensive rats and ameliorate the degree of portal-systemic shunting.

Management of portal hypertension after variceal hemorrhage

Each variceal bleed is associated with 20% to 30% risk of dying. Management of portal hypertension after a bleed consists of (1) control of bleeding and (2) prevention of rebleeding. Effective control of bleeding can be achieved either pharmacologically by administering somatostatin or octreotide or endoscopically via sclerotherapy or variceal band ligation. In practice, both pharmacologic and endoscopic therapy are used concomitantly. Rebleeding can be prevented by endoscopic obliteration of varices. In this setting, variceal ligation is the preferred endoscopic modality. B-blockade is as effective as endoscopic therapy and, in combination, the two modalities may be additive.

Management of acute variceal haemorrhage

Endoscopic therapy and in particular endoscopic variceal banding ligation, in experienced hands, is the treatment of choice for acute variceal bleeding which remains a major cause of death in patients with cirrhosis and portal hypertension. Pharmacological therapy with Glypressin or somatostatin can be useful to gain time when the endoscopic expertise is not available or to help to obtain a clearer endoscopic view. Transjugular intrahepatic porto-systemic stent shunt is currently used for endoscopic failures, producing similar results with the surgical portacaval shunts. Which one of the two should be preferred, since they both work best in relatively compensated patients, should be a balance between the available surgical and radiological expertise, the urgency of the situation and the expected course of the disease.

Acute gastrointestinal bleeding

Acute gastrointestinal bleeding is a significant worldwide medical problem. Despite modern measures for diagnosis and treatment, morbidity and mortality rates associated with gastrointestinal bleeding remain largely unchanged. Aggressive medical resuscitation while initiating an evaluation to localize the site of blood loss remains the key to successful management of acute gastrointestinal bleeding. A multidisciplinary approach with early involvement of a gastroenterologist, surgeon, and radiologist can be extremely helpful in the management of these patients. With the logical and direct approach to the evaluation of patients with gastrointestinal bleeding described in this article, most episodes can be managed successfully.

Drug treatment for bleeding oesophageal varices

At the time of diagnosis of cirrhosis, varices are present in about 60% of decompensated and 30% of compensated patients. The risk factors for the first episode of variceal bleeding in cirrhotic patients are the severity of liver dysfunction, a large size of the varices and the presence of endoscopic red colour signs, but only a third of patients who suffer variceal haemorrhage demonstrate the above risk factors. The only treatment that does not require sophisticated equipment or the skills of a specialist, and is immediately available, is vasoactive drug therapy. Hence, drug therapy should be considered to be the initial treatment of choice and can be administered while the patient is transferred to hospital, as has been done in one recent study. Moreover, drug therapy is no longer considered to be only a 'stop-gap' therapy until definitive endoscopic therapy is performed. Several recent trials have reported an efficacy similar to that of emergency sclerotherapy in the control of variceal bleeding. Furthermore, recent evidence suggests that those patients with high variceal or portal pressure are likely to continue to bleed or re-bleed early, implying that prolonged therapy lowering the portal pressure over several days may be the optimal treatment. Pharmacological treatment with beta-blockers is safe, effective and the standard long-term treatment for the prevention of recurrence of variceal bleeding. The combination of beta-blockers with isosorbide-5-mononitrate needs further testing in randomized controlled trials. The use of haemodynamic targets for the reduction of the HVPG response needs further study, and surrogate markers of the pressure response need evaluation. Ligation has recently been compared with beta-blockers for primary prophylaxis, but there is as yet no good evidence to recommend banding for primary prophylaxis if beta-blockers can be given.

Esophageal varices. I. Clinical presentation, medical therapy, and endoscopic therapy

The last half century has witnessed great advances in the understanding of the pathogenesis and natural history of portal hypertension in cirrhotics. Several pharmacologic and endoscopic techniques have been developed for the treatment of portal hypertension. The use of these agents in a given patient must be based on an understanding of the stage in the natural history of the disease and the relative efficacy and safety of the available treatment options.

Management of gastrointestinal bleeding induced by gastrointestinal endoscopy

Therapeutic gastrointestinal endoscopy has a much greater risk of inducing gastrointestinal hemorrhage than diagnostic endoscopy. For example, colonoscopic polypectomy has a risk of approximately 1.6% of inducing bleeding, compared with a risk of approximately 0.02% for diagnostic colonoscopy. Higher-risk procedures include colonoscopic polypectomy, endoscopic biliary sphincterotomy, endoscopic dilatation, endoscopic variceal therapy, percutaneous endoscopic gastrostomy, and endoscopic sharp foreign body retrieval. The risk of inducing hemorrhage is decreased by meticulous endoscopic technique. Hemorrhage from endoscopy may be immediate or delayed. Immediate hemorrhage should be immediately treated by endoscopic hemostatic therapy, including injection therapy, thermocoagulation, or electrocoagulation. Delayed hemorrhage generally requires repeat endoscopy for diagnosis and for therapy, using the same hemostatic techniques.

Beneficial effects of combined terlipressin and tetramethylpyrazine administration on portal hypertensive rats

The purpose of this study was to investigate the therapeutic effects of terlipressin (TP) alone or in combination with tetramethylpyrazine (TMP) on anesthetized portal hypertensive rats. Portal hypertension was induced by either partial portal vein ligation (PVL, without cirrhosis) or bile duct ligation (BDL, with cirrhosis) in Sprague-Dawley rats. Each PVL or BDL rat received only one of the two regimens: vehicle for 3 min followed by TP (0.017 mg·kg-1·min-1 for 3 min) or TMP (10 mg·kg-1·min-1 for 3 min) followed by TP. In PVL rats, infusion of vehicle followed by TP induced significant reduction of portal venous pressure (PVP, -15.0 ± 1.0%) and prominent elevation of mean arterial pressure (MAP, 57.3 ± 8.1%) as well as total peripheral resistance (TPR, 113 ± 11%) from baseline, and there was a cardiodepressant response (cardiac index, CI, -26.3 ± 1.1%). Infusion of TMP followed by TP induced significant reduction of PVP (-20.3 ± 0.4%) and CI (-9.9 ± 1.2%) and significant elevation of MAP (31.3 ± 2.5%) and TPR (46.0 ± 4.1%) from baseline. In BDL rats, infusion of vehicle followed by TP also induced significant reduction of PVP (-13.8 ± 1.7%) but an increase in MAP (57.1 ± 2.2%) and TPR (101 ± 6%) from baseline, and there also was a cardiodepressant response (CI, -21.4 ± 2.3%). Infusion of TMP followed by TP induced significant reduction of PVP (-18.9 ± 1.4%) and CI (-11.9 ± 2.1%), but an increase in MAP (36.2 ± 2.5%) and TPR (55.0 ± 5.2%). Compared with vehicle followed by TP, TMP not only significantly enhanced portal hypotensive (PVP reduction) effects of TP but also attenuated the systemic pressor (MAP and TPR elevation) and cardiodepressant (CI reduction) effects of TP in both PVL and BDL rats. Our results suggest that TP, alone or in combination with TMP, induced portal hypotensive effects in two models of portal hypertensive rats. Combination of TP and TMP was beneficial in enhancing portal hypotensive effects of TP and ameliorating the systemic pressor and cardiodepressant effects of TP.Key words: terlipressin, tetramethylpyrazine, cirrhosis, portal hypertension, hemodynamics.

Portal hypotensive effects of combined terlipressin and DL-028, a synthetic alpha 1 adrenoceptor antagonist administration on anesthetized portal hypertensive rats

AIMS/BACKGROUND

The purpose of this study was to investigate the therapeutic effects of terlipressin, alone or in combination with DL-028, a synthetic alpha 1-adrenoceptor antagonist on anesthetized portal hypertensive rats.

METHODS

Portal hypertension was induced by either partial portal vein ligation (PVL) or bile duct ligation (BDL) in Sprague-Dawley rats. Each portal hypertensive rat received only one of the two regimens: vehicle plus terlipressin or DL-028 plus terlipressin. Terlipressin dosage was 0.017 mg/kg/min infused for 3 min, while vehicle or DL-028 (0.50 microgram/kg/min) was continuously infused for 40 min, starting 10 min before terlipressin infusion.

RESULTS

In PVL rats, infusions of vehicle plus terlipressin induced significant, maximum reduction of portal venous pressure (PVP, -11.0 +/- 1.8%) and prominent elevation of mean arterial pressure (MAP, 50.3 +/- 9.0%) from baseline. Infusions of DL-028 plus terlipressin induced maximum PVP reduction (-17.5 +/- 2.8%) and MAP elevation (39.8 +/- 7.4%). In BDL rats, infusion of vehicle plus terlipressin also induced significant, maximum reduction of PVP (-6.8 +/- 2.1%) and prominent elevation of MAP (61.4 +/- 7.8%) from baseline. Infusions of DL-028 plus terlipressin induced maximum PVP reduction (-17.9 +/- 2.2%) and MAP elevation (47.9 +/- 7.4%). Compared to vehicle plus terlipressin, DL-028 significantly enhanced portal hypotensive effects of and attenuated systemic pressor effects of terlipressin in both PVL and BDL rats.

CONCLUSIONS

Our results suggest that terlipressin, alone or in combination with DL-028, induced portal hypotensive effects in portal hypertensive rats. The combination of terlipressin with DL-028 was beneficial in enhancing the portal hypotensive effects and ameliorating the systemic pressor effects of terlipressin.

Haemodynamic effects of 8-day octreotide and prazosin administration in portal hypertensive rats

BACKGROUND

Octreotide and prazosin are both effective portal hypotensive drugs in the control or prevention of variceal bleeding. The present study was undertaken to investigate the haemodynamic effects of octreotide and prazosin, alone or in combination, in portal hypertensive rats.

METHODS

Portal hypertension was induced by partial portal vein ligation. Portal hypertensive rats were allocated into one of the four groups-vehicle group (saline, 0.5 mL 12 h-1), octreotide group (30 micrograms kg-1 12 h-1), prazosin group (0.4 mg kg-1 12 h-1), and octreotide (30 micrograms kg-1 12 h-1) plus prazosin (0.4 mg kg-1 12 h-1) group-with eight rats in each group. Prazosin or saline was administered by gavage, whereas octreotide was administered by subcutaneous injection. The drug was given on the day of ligation and continued for 8 consecutive days. Systemic as well as splanchnic haemodynamic parameters were measured thereafter.

RESULTS

Portal vein-ligated rats exhibited typical hyperdynamic state compared with sham-operated rats. The portal venous pressure, portal tributary blood flow and cardiac index were significantly reduced by treatment of octreotide, prazosin or octreotide plus prazosin in portal hypertensive rats. Hyperdynamic parameters of systemic, renal and portal territory vascular resistances, and renal as well as hepatic arterial blood flow were ameliorated by treatment of octreotide or octreotide plus prazosin in portal hypertensive rats. Overall, octreotide treatment exerted more beneficial haemodynamic effects than prazosin treatment. The combination of octreotide and prazosin exerted better haemodynamic effects in cardiac index but worse effects in systemic as well as portal territory vascular resistance than octreotide treatment alone.

Advances in drug therapy for acute variceal haemorrhage

Recent advances in the pharmacology of portal hypertension are reviewed, against the background of existing knowledge and current clinical research. The most recent trials are analysed, and conclusions made about the use of drugs in acute variceal haemorrhage, as well as directions for further clinical trials and research.

Review article: the role of pharmaco-therapy for acute variceal haemorrhage in the era of endoscopic haemostasis

In the last decade, endoscopic haemostasis, including injection sclerotherapy and variceal ligation has become the standard method for the treatment of variceal haemorrhage. While the use of vasopressin has been hampered by severe side effects, the development of new vasoactive agents such as terlipressin, somatostatin and octreotide has opened new indications for these pharmacological therapies. These agents are effective, safe and easy to use. They could be recommended as stop-gap treatment before endoscopy can be arranged. They can also be used as adjunct therapy for endoscopic haemostasis in acute variceal haemorrhage.

Haemodynamic effects of combined treatment with molsidomine and propranolol on portal hypertension in conscious and unrestrained cirrhotic rats

We investigated the systemic and splanchnic haemodynamic effects of combined treatment with molsidomine and propranolol on cirrhotic rats. Liver cirrhosis was produced by repeated intraperitoneal injections of thioacetamide. The blood flow of each organ was measured serially using the radioactive microsphere method in the awake state before and after the administration of each agent. Cirrhotic rats received molsidomine (0-.5 mg/kg), propranolol (0.1 or 0.2 mg/min), both agents or placebo. Combination treatment with molsidomine and 0.1 mg/min propranolol significantly reduced portal pressure compared with molsidomine or propranolol alone (21 +/- 4 vs 15 +/- 3 or 11 +/- 2% P < 0.05). Systemic haemodynamic changes with this combined treatment were mild. This combined treatment slightly inhibited the molsidomine-induced decrease in portal vascular resistance (27 +/- 9 vs 31 +/- 6; NS) and markedly inhibited the molsidomine-induced decrease in splanchnic arterial resistance (7 +/- 6 vs 27 +/- 5% P < 0.05). Compared with low-dose propranolol administration, the combined treatment was associated with a significant decrease in portal vascular resistance (27 +/- 9% decrease vs 2 +/- 2% increase; P < 0.001) and a significant decrease in splanchnic arterial resistance (7 +/- 6% decrease vs 5 +/- 4% increase P < 0.05). The combination of molsidomine and high-dose propranolol (0.2 mg/min) caused a marked reduction in portal venous inflow, mean arterial pressure and cardiac index. We conclude that propranolol enhances the molsidomine-induced decrease in portal pressure by splanchnic vasoconstriction in association with a slight decrease in portal vascular resistance. The combination therapy with molsidomine and low-dose propranolol combination had more beneficial and less harmful effects on systemic and splanchnic haemodynamics and thus appears to be a superior method for treating portal hypertension.

Upper gastrointestinal tract bleeding

Upper GI bleeding is a serious and common emergency. Most upper GI bleeding will stop spontaneously but determining which patients will continue to bleed or rebleed is very difficult in the ED. Resuscitation and stabilization are the primary goals of the emergency physician. Hemorrhage control with pharmacotherapy or balloon tamponade may be necessary until urgent or emergent consultation with a gastroenterologist or surgeon is obtained. Early detection and treatment of H. pylori and the development of safer NSAIDs should alter the future of upper GI bleeding dramatically.

A meta-analysis of somatostatin versus vasopressin in the management of acute esophageal variceal hemorrhage

BACKGROUND & AIMS

Although sclerotherapy is the current standard therapy for bleeding esophageal varices, the best method for initial control is unclear. The aim of this meta-analysis was to compare the efficacy and toxicity of somatostatin and vasopressin in short-term treatment of hemorrhage from esophageal varices.

METHODS

Using MEDLINE, all randomized trials comparing somatostatin with vasopressin in subjects with endoscopically documented acute esophageal variceal bleeding were identified. The quality of each study was critically and independently evaluated, and quantitative data for initial cessation of bleeding, sustained control of bleeding, and major adverse effects were abstracted. The relative risk (RR) and number needed to be treated were calculated.

RESULTS

The RR or likelihood of achieving initial control of bleeding with somatostatin vs. vasopressin was 1.62 (95% confidence interval [CI], 1.37-1.93), and the number needed to be treated was 3.7, i.e., between 3 and 4 patients would have to be treated with somatostatin for 1 patient to derive additional benefit over vasopressin. For trials that measured sustained control of bleeding, somatostatin was superior to vasopressin (RR, 1.28 [95% CI, 1.00-1.65]; number needed to be treated, 8.8). The risk of adverse effects was greater for subjects given vasopressin (10% vs. 0%; P = 0.00007).

CONCLUSIONS

This meta-analysis suggests that somatostatin is more efficacious in controlling acute hemorrhage from esophageal varices and has a lower risk of adverse effects than vasopressin.

Current management of oesophageal varices

Patients with chronic liver disease and large varices with endoscopic features which put them at high risk of bleeding, especially if they have a HVPG of more than 12 mmHg, should be treated with beta-blockers at a dose which lowers their pulse by 25%, as prophylaxis against future bleeding. Once a patient bleeds from oesophageal varices, emergency treatment with octreotide should be commenced until endoscopic sclero- or ligation therapy is performed. If these treatments are not readily available, or if bleeding continues in spite of treatment, balloon tamponade is employed to arrest bleeding. In the event of recurrent bleeding, further sclero- or ligation therapy should be attempted, but continued bleeding would dictate surgical therapy or insertion of a TIPS. What operation is performed would depend on the local expertise. In a suitable candidate, liver transplantation would be considered. If bleeding is controlled by sclero- or ligation therapy, chronic sclerotherapy should be continued until the varices are obliterated, and beta-blockers commenced. Regular follow-up should be arranged to encourage abstinence from alcohol if appropriate, and to decide the most opportune time for transplantation if indicated.

Haemodynamic effects of enalaprilat on portal hypertension in patients with HBsAg-positive cirrhosis

It has been suggested that enalaprilat inhibits the renin-angiotensin-aldosterone system in plasma and tissue; it may therefore reduce portal vascular pressure owing to secondary hyperaldosteronism in patients with liver cirrhosis. In order to evaluate this concept, 20 patients with hepatitis B surface antigen (HBsAg)-positive liver cirrhosis and portal hypertension received an intravenous infusion of 2.5 mg of enalaprilat. Wedged hepatic venous pressure, free hepatic venous pressure and cardiac index were measured before, immediately after, and then 15 min, 30 min and 1 h after intravenous enalaprilat infusion. The mean pressure gradient between wedged hepatic venous pressure and free hepatic venous pressure was significantly decreased, by 13% immediately after, 18% at 15 min, 23% at 30 min and 13% at 1 h after infusion of enalaprilat. Thirteen patients experienced a decrease of hepatic venous pressure gradient (HVPG) greater than 5 mmHg, another three 3-5 mmHg and the remaining four patients exhibited no significant change in HVPG. Systemic haemodynamic indices, including pulmonary arterial pressure, pulmonary capillary wedge pressure and central venous pressure, decreased significantly at 15 and 30 min after enalaprilat infusion (P < 0.01). Liver function, renal function and blood routine before and after enalaprilat infusion showed no significant change. There were no adverse effects during or after enalaprilat infusion. We conclude that enalaprilat infusion can quickly and safely reduce the hepatic venous pressure gradient in patients with HBsAg-positive cirrhosis.

Vasoconstrictors in the management of bleeding from oesophageal varices. A clinico-economic appraisal in the UK

BACKGROUND

Bleeding from oesophageal varices is an uncommon but potentially fatal condition that often leads to expensive hospitalizations in intensive care or high-dependency units.

METHODS

To assess the clinical and economic impact of this condition, we have devised a management plan illustrating current clinical practice in the UK.

RESULTS

Approximately 6.1 million pounds of NHS resources are devoted to the treatment of 3000 acute hospital admissions for variceal bleeding every year. Vasoconstrictors like vasopressin may save approximately 36 lives per annum for an additional 145 thousand pounds. However, current clinical practice requires vasopressin to be concurrently administered with intravenous glyceryl trinitrate, increasing overall costs by 582 thousand pounds to a total of 6.7 million pounds. The additional cost for each extra life saved is estimated at 16,180 pounds.

CONCLUSION

The efficacy of current vasoconstrictors requires further confirmation. In particular, new agents like octreotide (Sandostatin) should be carefully assessed to determine their potential clinical and economic benefits.

Acute effects of sublingual nitroglycerin on hepatic blood flow in healthy volunteers

Duplex sonography was used to assess the effects on hepatic blood flow after administering 0.6 mg nitroglycerin (NTG) sublingually to ten healthy volunteers. The study was a randomized, placebo-controlled, cross-over study in which subjects were studied on three separate occasions. Each visit involved administering either placebo or NTG followed by estimation of blood flow through a particular branch of the hepatic artery, portal vein, and hepatic vein every minute for 15 minutes after NTG and placebo administration. Two hours later, subjects were crossed over to the other treatment and the same vessel branch was again examined for 15 minutes. Total blood flow increased 7% in the portal vein and 27% in the hepatic vein during NTG treatment, but did not change significantly in the hepatic artery. Vascular resistance was increased in the hepatic artery and decreased in the portal and hepatic veins after NTG. Qualitatively, flow changed dramatically in the hepatic vein after NTG with the disappearance of normal retrograde flow. The results indicate that nitroglycerin effects hepatic blood flow through the portal and hepatic veins with a decrease in vascular resistance in the portal and hepatic veins and an increase in resistance in the hepatic artery.

Hemodynamic effects of combined treatment with somatostatin analogue (SMS 201-995) and low-dose isosorbide dinitrate on portal hypertension in conscious cirrhotic rats

The authors investigated whether combined treatment with the somatostatin analogue, SMS 201-995, and low-dose isosorbide dinitrate enhanced the hemodynamic effects of the individual agents on rats with thioacetamide-induced cirrhosis. Four groups of cirrhotic rats received SMS 201-995 (0.1 microgram.min-1.kg-1), isosorbide dinitrate (10 micrograms.min-1.kg-1), both agents, or placebo, respectively. Hemodynamics were measured serially in conscious rats, using a radioactive microsphere method. SMS 201-995 reduced portal venous inflow 21 +/- 4% and portal pressure 17 +/- 3%. Isosorbide dinitrate decreased portal venous inflow 20 +/- 4%, by inducing splanchnic vasoconstriction mediated by low pressure baroreflexes, and this agent also decreased portal pressure, by 14 +/- 2%. Portal venous resistance rose 7.6 +/- 3% with isosorbide dinitrate alone, but decreased 18 +/- 4% with combination therapy. This effect may have been induced by the pronounced vasodilatory effect of isosorbide dinitrate on the venous vasculature, since the reflex splanchnic vasoconstriction that occurs with low-dose isosorbide dinitrate disappears when this agent is combined with SMS 201-995. The decrease in portal pressure was more marked (22 +/- 4%) and changes in systemic hemodynamics were milder with the combined treatment. It was concluded that combination therapy with SMS 201-995 and low-dose isosorbide dinitrate may be beneficial for portal hypertension in liver cirrhosis.

Terlipressin or vasopressin plus transdermal nitroglycerin in a treatment strategy for digestive bleeding in cirrhosis. A randomized clinical trial. Liver Study Group of V. Cervello Hospital

Between 1988 and 1990 an unblinded, randomized trial of terlipressin or vasopressin plus transdermal nitroglycerin, as part of a treatment strategy including emergency sclerotherapy for actively bleeding varices, was conducted during 165 admissions in 137 patients with cirrhosis and upper digestive bleeding. Eighty-four patient admissions were assigned to terlipressin (2 mg every 6 h) and 81 to vasopressin (0.4 to 0.8 unit per min) plus transdermal nitroglycerin (20 to 80 mg). The two groups were comparable for relevant clinical data, but there were slightly more patients with hepatocellular carcinoma or terminal conditions in the terlipressin group. After the 24-h study period, failure to control bleeding was 20/84 (25%) in the vasopressin and 14/81 (17%) in the terlipressin group (p = 0.19). Corresponding figures for patients bleeding from varices (emergency sclerotherapy in 43 and 45, respectively) were 13/55 (24%) and 5/56 (9%; p = 0.035), from other sources 5/16 (31%) and 2/15 (13%; p = 0.23), from undefined sources 2/10 (20%) and 7/13 (54%; p = 0.1). In a logistic multivariate regression model the odds ratio for terlipressin adjusted for prognostic factors was 0.45 (p = 0.07). There were seven major side effects requiring treatment discontinuation in the vasopressin and one in the terlipressin group. These results suggest that terlipressin alone is as effective as vasopressin plus transdermal nitroglycerin, with less severe side effects, in 24-h control of upper gastrointestinal bleeding in patients with cirrhosis.

Effects of vasopressin and nicardipine on hemodynamics and liver function in patients with cirrhosis: comparison with vasopressin alone

The effects of a combination of vasopressin and a calcium channel blocker (nicardipine) on portohepatic hemodynamics and liver function were compared with the effects of vasopressin alone in 18 patients with portal hypertension. Nine patients received 0.4 units/min of vasopressin and 9 patients received the same dose of vasopressin plus 0.3 mg/min of nicardipine for 40 min. Vasopressin plus nicardipine induced a significant reduction in both free portal venous pressure and the portal venous pressure gradient. These effects were similar to the changes with vasopressin alone (-14% vs. -16% in free portal venous pressure; -29% vs. -31% in portal venous pressure gradient). Vasopressin decreased both hepatic blood flow (-34%, P < 0.01) and intrinsic clearance of indocyanine green (-22%, P < 0.05). In contrast, these two parameters did not significantly change after vasopressin plus nicardipine (-8% and -3%, respectively). These results suggest that the addition of nicardipine improves hepatic impairment induced by vasopressin but causes no further reduction on portal pressure.

Comparison of the effects of various vasodilators on the rat portal vein and mesenteric artery

The effects of various vasodilators on isolated helical strips of rat portal vein and mesenteric artery were examined. Dilazep, ibudilast, nifedipine, verapamil and papaverine relaxed the KCl- and norepinephrine-induced contractions of the portal vein to a greater extent than they relaxed those of mesenteric artery. Dibutyryl cyclic AMP and NKH477 did not show any significant difference in terms of the concentrations that produced 50% inhibition (IC50) of the KCl-induced contraction of the portal vein and mesenteric artery. The relaxant effects of nitroprusside and isosorbide dinitrate on the KCl- and norepinephrine-induced contractions of the portal vein were less potent than their effects on contractions of the mesenteric artery. The agents that inhibited the contractions of the portal vein more potently than those of the mesenteric artery were associated with parallel shifts to the right of the concentration-response curves for CaCl2 in both preparations. These results suggest that drugs with a Ca2+ channel blocking action may be preferable to those that cause a decrease in portal pressure for treatment of portal hypertension.

Treatment of acute gastroesophageal variceal hemorrhage

About 30% to 35% of patients with portal hypertension bleed from gastroesophageal varices and mortality remains high reflecting the challenges of effectively dealing with the bleeding event itself and the problems of underlying liver disease. Careful resuscitation and control of risk of complications is the most essential element of medical therapy (Fig. 2). Use of newer, more effective drug combinations with vasopressin or somatostatin permit control of hemorrhage in the majority of patients with fewer drug-induced complications. Endoscopic sclerotherapy and, more recently, banding therapy provide immediate control of hemorrhage and eradication of varices and rebleeding in up to 90% of patients. Persistent, recurrent bleeding in the small number of remaining patients can be effectively managed by "portacaval shunt rescue" or orthotopic liver transplantation in selected cases with acceptable surgical morbidity and mortality. The contribution and role of the TIPS procedure is unknown but very promising; at least as a bridge procedure in patients awaiting transplantation. Until appropriate prospective, comparative trials are performed, the role of TIPS as a long-term alternative to portacaval shunt surgery or other endoscopic or surgical options remains unknown.

Hepatic hemodynamic features in patients with esophageal or gastric varices

One hundred and fifty cirrhotic patients with or without esophageal varices and/or gastric varices were investigated by endoscopy and hepatic venous catheterization to evaluate differences in the degree of portal hypertension, main portal venous diameter and frequency of portal systemic encephalopathy. Hemodynamic values were correlated with varices size as assessed by endoscopy. Patients with large gastric varices had wedged hepatic venous pressures and hepatic venous pressure gradients which were lower than patients with esophageal varices only, but similar to patients without varices. In addition, in patients with large gastric varices, a decrease in the diameter of the main portal vein and an increase in the incidence of chronic portal systemic encephalopathy were noted. Our results implied that patients with large gastric varices presented different hemodynamic features including the degree of portal hypertension and the incidence of portal systemic encephalopathy from patients with esophageal varices only.

Does propranolol maintain post-sclerotherapy variceal obliteration? A prospective randomized study

Variceal recurrence and rebleeding are common after initial obliteration by injection sclerotherapy. To investigate whether propranolol can maintain variceal obliteration by sclerotherapy, 59 patients with oesophageal variceal bleeding after sclerotherapy were enrolled. Patients were allocated to propranolol treatment (30 patients) or served as controls (29 patients). After a mean follow up of 2 years and 4 months, 53 patients completed the study. Fifty-eight per cent of the propranolol group versus 77% of the control group experienced recurrent varices (P = 0.20). Fifteen per cent of the propranolol group versus 11% of the control group developed cardiac varices. Recurrent variceal bleeding was encountered in 27% of the propranolol group and 19% of the control group. Three patients in the propranolol group, compared with two patients in the control group, died of massive variceal bleeding. Eighty per cent of them bled from cardiac varices. Both groups had similar survival rates. We therefore concluded that the use of propranolol after variceal obliteration by sclerotherapy can neither prevent oesophagogastric variceal recurrence nor prevent further rebleeding.

The management of active variceal bleeding

A systematic review of available treatments for controlling active variceal bleeding provides important guidelines for choosing an overall strategy. The initial prerequisite of a diagnostic endoscopy provides the opportunity for early intervention with local endoscopic techniques, such as injection sclerotherapy, direct intravariceal injection of tissue adhesives and banding ligation of varices. This approach currently represents the optimal strategy. If the endoscopic expertise is not available, the use of vasoactive drugs may provide temporary control of bleeding while allowing time for more definitive treatment. Vasopressin and its analogues are the most widely used vasoactive drugs, but somatostatin holds promise. In view of the systemic haemodynamic complications associated with vasopressin (and probably glypressin), these drugs should be given in combination with nitrates. Balloon tamponade remains an important alternative for patients in whom massive, life-threatening haemorrhage has occurred. Surgical techniques, such as shunting and devascularisation, are increasingly reserved for the management of variceal bleeding that endoscopic therapy has failed to control.

Portal hypertension and bleeding esophageal varices

Bleeding from esophageal varices exacts a high mortality and extraordinary societal costs. Prophylaxis--medication, sclerotherapy, or shunt surgery to prevent an initial bleeding episode--is ineffective. In patients who have bled from varices, endoscopic injection sclerotherapy can control acute bleeding in more than 90% of patients. Because recurrent bleeding frequently occurs and survival without definitive therapy is dismal, selection of a permanently effective treatment is mandatory once variceal bleeding has been controlled. Long-term injection sclerotherapy can be performed in compliant patients; it is relatively safe but is associated with a 30-50% rebleeding rate. Beta-blockers significantly reduce portal pressure and recurrent bleeding but have not been shown to diminish mortality from BEV. Portal decompressive surgery permanently halts bleeding in more than 90% of patients; the risk of operative mortality is high in decompensated cirrhotics, and long-term complications of encephalopathy and accelerated liver failure may limit indications for shunt surgery to good-risk cirrhotics who are not liver transplant candidates. Devascularization procedures have a low operative mortality and encephalopathy rate but unacceptably high rates of recurrent bleeding. Liver transplantation is curative therapy for bleeding esophageal varices and the associated underlying hepatic dysfunction; cost and availability of donor organs generally limit its use in this setting to variceal bleeders with end-stage liver disease not associated with active alcoholism.

A randomized controlled trial comparing octreotide and vasopressin in the control of acute esophageal variceal bleeding

This randomized controlled trial was conducted to compare the efficacy of intravenous infusion of octreotide (a synthetic long-acting somatostatin analogue) with vasopressin in 48 cirrhotic patients with endoscopically proven bleeding esophageal varices. Twenty-four patients received a continuous infusion of octreotide 25 micrograms/h for 24 h after an initial bolus of 100 micrograms and another 24 patients received a continuous infusion of vasopressin 0.4 U/min for 24 h. Bleeding was initially controlled after 6 h of drug infusion in 88% (21/24) and 54% (13/24) of the patients treated with octreotide and vasopressin respectively (p = 0.03). Complete control of bleeding after 24 h of drug infusion was achieved in 15 (63%) patients receiving octreotide and in 11 (46%) patients receiving vasopressin (p > 0.05). Side effects during drug infusion such as headache, chest pain and abdominal pain were significantly lower in the octreotide group (3/24) than in the vasopressin group (11/24). Serum gastrin and insulin levels fell significantly following octreotide infusion, but plasma glucose levels remained unchanged. Mortality related to bleeding esophageal varices was no different between the two groups. This report showed that octreotide infusion was more effective and had fewer side effects than vasopressin in initial controlling of acute esophageal variceal bleeding until an elective endoscopic sclerotherapy could be performed.

Review article: the pathophysiology and pharmacological treatment of portal hypertension

The pathogenesis of portal hypertension remains poorly understood. Similarly, pharmacological manipulation for the prevention and treatment of variceal haemorrhage has not fulfilled the promise of the 1980s. This article reviews current concepts in the pathophysiology of portal hypertension and considers pharmacotherapy for the treatment of variceal bleeding.

A prospective randomised controlled trial comparing the efficacy of somatostatin with injection sclerotherapy in the control of bleeding oesophageal varices

Since previous reports have suggested that somatostatin may be of value in the control of acute variceal haemorrhage, we compared its efficacy with that of injection sclerotherapy in a randomised controlled clinical trial. Eighty consecutive patients with endoscopically-proven severe variceal bleeding were randomised to injection sclerotherapy (n = 41) or somatostatin (n = 39) given as a continuous infusion of 250 micrograms/h for 5 days plus daily bolus administration of 250 micrograms. The efficacy of injection sclerotherapy and somatostatin infusion in controlling haemorrhage and preventing rebleeding (censored at 5 days), mortality (censored at 28 days) and complications was compared. The aetiology of the portal hypertension and transfusion requirements was similar between the two groups, but there were more patients with severe liver disease (Child's C) in the somatostatin group. There was no significant difference between the two treatments in the initial (p = 1.0) or overall control of bleeding (p = 0.58). Furthermore, somatostatin was as effective as injection sclerotherapy in controlling bleeding in patients with severe liver disease or in those actively bleeding at the time of their endoscopy. The relative risk of rebleeding whilst receiving somatostatin compared to injection sclerotherapy was 1.39 [95% Confidence Interval (CI) 3.73; 0.52], but this was reduced to 0.98 (95% CI 0.37; 2.67) when readjusted for Child's grading, the only prognostic factor shown to be of significance. Mortality was not significantly different between the two groups of patients (p = 0.31). The relative risk of dying whilst receiving somatostatin compared to injection sclerotherapy was 1.6 (95% CI 3.93; 0.66) but was reduced to 1.03 (95% CI 0.47; 2.47) when adjusted for Child's grading, the only significant prognostic factor. Complications in the somatostatin group were minor and less frequent than after injection sclerotherapy. The results of this study indicate that somatostatin is a safe treatment, which is as effective an endoscopic injection sclerotherapy for acute variceal bleeding.