Review article: a critical comparison of drug therapies in currently used therapeutic strategies for variceal haemorrhage

Variceal bleeding: consensus meeting report from the Brazilian Society of Hepatology

In the last decades, several improvements in the management of variceal bleeding have resulted in a significant decrease in morbidity and mortality of patients with cirrhosis and bleeding varices. Progress in the multidisciplinary approach to these patients has led to a better management of this disease by critical care physicians, hepatologists, gastroenterologists, endoscopists, radiologists and surgeons. In this respect, the Brazilian Society of Hepatology has, recently, sponsored a consensus meeting in order to draw evidence-based recommendations on the management of these difficult-to-treat subjects. An organizing committee comprised of four people was elected by the Governing Board and was responsible to invite 27 researchers from distinct regions of the country to make a systematic review of the subject and to present topics related to variceal bleeding, including prevention, diagnosis, management and treatment, according to evidence-based medicine. After the meeting, all participants met together for discussion of the topics and the elaboration of the aforementioned recommendations. The organizing committee was responsible for writing the final document. The meeting was held at Salvador, May 6th, 2009 and the present manuscript is the summary of the systematic review that was presented during the meeting, organized in topics, followed by the recommendations of the Brazilian Society of Hepatology.

Management of Cirrhosis and Associated Complications

Liver cirrhosis is the encapsulation or replacement of injured tissue by collagen, resulting in end-stage liver disease and portal hypertension. The consequences of cirrhosis are impaired hepatocyte function, increase intrahepatic circulatory resistance, portal hypertension, and the development of hepatocellular carcinoma. Complications include encephalopathy, coagulopathy, varices, ascites, spontaneous bacterial peritonitis, epatorenal syndrome, and hepatopulmonary syndrome. Managing patients with acute or chronic liver failure is challenging, and liver failure may have profound effects on other organ systems. Most therapies are directed at managing the complications and bridging patients to liver transplantation. The clinician must be aware of the pathologic presentations and the appropriate management, including pharmacologic and nonpharmacologic therapies, goals and end points of therapy, and monitoring of therapy. This review focuses on the management of the complications directly associated with liver dysfunction (encephalopathy and coagulopathy) and portal hypertension (varices, ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, hepatopulmonary syndrome).

Effects of ocreotide on intestinal mucosa in rats with portal hypertensive enteropathy

To clarify the effects of long-term ocreotide (a long-acting somatostatin analogue) treatment on mucosal changes in a rat model of portal hypertensive enteropathy, groups of male Swiss albino rats (n=15 each) were randomly assigned to one of three treatment arms. These were: sham laparotomy+twice daily subcutaneous saline 0.5 mL (Group 1); portal hypertension induction+twice daily subcutaneous saline 0.5 mL (Group 2); and portal hypertension induction+subcutaneous ocreotide 100 microg/kg/12h (Group 3). After 12 weeks of treatment, jejunal and ileal tissue specimens were obtained and evaluated histopathologically (villus/crypt ratio, mean diameter of dilated vessels, mucosal edema, and fibromuscular proliferation in the lamina propria) and immunohistochemically (vascular endothelial growth factor (VEGF), von Willebrand factor (F8), and cluster of differentiation 34 (CD34) labelling). In jejunal specimens, the villus/crypt ratio was markedly lower in Group 2 (2.38+/-0.46 microm) than in Group 1 (5.07+/-2.25 microm) or Group 3 (4.97+/-2.19 microm); mean diameter of dilated vessels was markedly higher in Group 2 (43.30+/-5.71 microm) than in Group 1 (33.53+/-4.00 microm) or Group 3 (36.76+/-3.96 microm); mucosal edema and fibromuscular proliferation were universally absent in Group 1 when compared with the other groups. There were statistically significant differences (p<0.05) between Groups 1 and 2 for villus/crypt ratio, mean diameter of dilated vessels, VEGF immunolabelling intensity, and CD34 immunolabelling intensity; between Groups 1 and 3 for mean diameter of dilated vessels, VEGF immunolabelling intensity, and CD34 immunolabelling intensity; and between Groups 2 and 3 for villus/crypt ratio, mean diameter of dilated vessels, and VEGF immunolabelling intensity. In ileal tissue specimens, the villus/crypt ratio was markedly lower in Group 2 (5.51+/-0.67 microm) than in either Group 1 (7.19+/-2.18 microm) or Group 3 (7.62+/-2.58 microm); mean diameter of dilated vessels was markedly higher in Group 2 (46.36+/-4.77 microm) than in either Group 1 (36.43+/-4.57 microm) or Group 3 (41.31+/-4.70 microm); while mucosal edema was absent in Group 1, it was present in Group 2 and Group 3; and fibromuscular proliferation was universally absent. There were statistically significant differences (p<0.05) between Groups 1 and 2 for villus/crypt ratio and mean diameter of dilated vessels; between Groups 1 and 3 for mean diameter of dilated vessels; and between Groups 2 and 3 for villus/crypt ratio, mean diameter of dilated vessels, and VEGF immunolabelling intensity. Together, these findings indicate that ocreotide treatment ameliorates histomorphological changes in a rat model of portal hypertensive enteropathy.

Pharmacologic Interventions for the Management of Critical Bleeding

Hospital pharmacists are often consulted for their knowledge about coagulation and therapeutic interventions for the management of critical bleeding. Many pharmacotherapies are available for this purpose, both systemic and topical, and others are in development. These agents and their mechanisms of action are reviewed, and perspectives are provided regarding their use in various clinical settings. Also provided are associated precautions to promote safe use. Current controversies surrounding pharmacotherapeutic agents used to control serious bleeding (e.g., in various types of surgery, trauma, obstetrics, and intracranial hemorrhage) are also discussed.

An economic evaluation of vasoactive agents used in the United Kingdom for acute bleeding oesophageal varices in patients with liver cirrhosis

OBJECTIVE

To conduct an economic evaluation of terlipressin, octreotide and placebo in the treatment of bleeding oesophageal varices (BOV) where endotherapy could be used concomitantly.

METHODS

A discrete event simulation model was created with transition states: bleeding, no bleeding, no bleeding post transjugular intrahepatic portosystemic shunt, post-salvage surgery, and death. Efficacy data on survival, re-bleeding and control of bleeding were obtained from high quality studies reported in Cochrane meta-analyses. Baseline outcomes related to the course of disease and health-state utilities were derived from published sources. Vasoactive treatment costs and all related BOV costs were obtained from published UK sources.

RESULTS

The average aggregated treatment cost per person for all medical interventions at 1 year was lower for terlipressin-treated patients (2623 pounds sterling) compared with those treated using octreotide (2758 pounds sterling) or placebo (2890 pounds sterling). The incremental analysis comparing terlipressin with octreotide and placebo using a cost per quality adjusted life year (QALY) and cost per life year gained (LYG) approach indicated that terlipressin was the dominant BOV treatment option (i.e. it cost less and it was more effective). Based on a maximum willingness to pay of 20,000 pounds sterling/QALY terlipressin was more effective and cost-saving compared to octreotide and placebo for simulations ranging from 42 days to 2 years. In point estimation analyses octreotide was dominant compared to placebo; however, probabilistic sensitivity analysis indicated that octreotide was unlikely to be cost-effective compared to placebo.

CONCLUSIONS

The findings indicated that vasoactive treatment in BOV was cost-saving compared to no vasoactive treatment. Furthermore, terlipressin was the more cost-effective vasoactive treatment for BOV in cirrhotic patients.

Current management of the complications of portal hypertension: variceal bleeding and ascites

Portal hypertension is one of the main consequences of cirrhosis. It results from a combination of increased intrahepatic vascular resistance and increased blood flow through the portal venous system. The condition leads to the formation of portosystemic collateral veins. Esophagogastric varices have the greatest clinical impact, with a risk of bleeding as high as 30% within 2 years of medium or large varices developing. Ascites, another important complication of advanced cirrhosis and severe portal hypertension, is sometimes refractory to treatment and is complicated by spontaneous bacterial peritonitis and hepatorenal syndrome. We describe the pathophysiology of portal hypertension and the current management of its complications, with emphasis on the prophylaxis and treatment of variceal bleeding and ascites.

Severe ischemia of the lower limb and of the intestine associated with systemic vasoconstrictor therapy and femoral arterial catheterization

OBJECTIVE

To report a case of peripheral and intestinal ischemia associated with arterial catheterization and terlipressin treatment in a child.

DESIGN

Case report.

SETTING

Pediatric intensive care unit of a university hospital.

PATIENT

The patient was a 2-month-old female infant with shock refractory to treatment with catecholamines, who received treatment with terlipressin (20 microg/kg/4 hrs). In order to monitor her cardiac output, the right femoral artery was catheterized with a 4-Fr PiCCO catheter. At 60 hrs, the patient presented progressive ischemia of the right lower limb and intestinal ischemia. The ischemia did not improve despite withdrawal of the catheter and interruption of the terlipressin administration; it progressed to massive intestinal ischemia, and the patient died.

CONCLUSIONS

Arterial catheterization combined with the administration of vasoconstrictor drugs, particularly vasopressin or terlipressin, can lead to local ischemic complications and severe intestinal ischemia in infants in shock.

Pro/con debate: octreotide has an important role in the treatment of gastrointestinal bleeding of unknown origin?

Whether it is the primary reason for admission or a complication of critical illness, upper gastrointestinal bleeding is commonly encountered in the intensive care unit. In this setting, in the absence of endoscopy, intensivists generally provide supportive care (transfusion of blood products) and acid suppression (such as proton pump inhibitors). More recently, octreotide (a somatostatin analogue) has been used in such patients. However, its precise role in patients with upper gastrointestinal bleeding is not necessarily clear and the drug is associated with significant costs. In this issue of Critical Care, two expert teams debate the merits of using octreotide in non-variceal upper gastrointestinal bleeding.

Portal hypertension: from pathophysiology to clinical practice

Portal hypertension (PHT) is responsible for the more severe and often lethal complications of cirrhosis such as bleeding oesophageal varices, ascites, renal dysfunction and hepatic encephalopathy. Because of the combined impact of these complications, PHT remains the most important cause of morbidity and mortality in patients with cirrhosis. Over the years, it has become clear that a decrease in portal pressure is not only protective against the risk of variceal (re)bleeding but is also associated with a lower long-term risk of developing complications and an improved long-term survival. A milestone in therapy was the introduction of non-selective beta-blockers for the prevention of bleeding and rebleeding of gastro-esophageal varices. However, in practice, less than half the patients under beta-blockade are protected from these risks, supporting the overall demand for innovation and expansion of our therapeutic armamentarium. Recent advances in the knowledge of the pathophysiology of cirrhotic PHT have directed future therapy towards the increased intrahepatic vascular resistance, which, in part, is determined by an increased hepatic vascular tone. This increased vasculogenic component provides the rationale for the potential use of therapies aimed at increasing intrahepatic vasorelaxing capacity via gene therapy, liver-selective nitric oxide donors and statines on the one hand, and at antagonizing excessive intrahepatic vasoconstrictor force through the use of endothelin antagonists, angiotensin blockers, alpha(1) adrenergic antagonists or combined alpha(1)- and non-selective beta-blockers or somatostatin analogues on the other. The focus of this review is to give an update on the pathophysiology of PHT in order to elucidate these potential novel strategies subsequently.

Octreotide exerts only acute, but no sustained, effects on MRI enhancement of liver metastases in carcinoid syndrome

We have investigated the acute and sustained hemodynamic effects of octreotide on hepatic metastases of midgut carcinoids using contrast-enhanced dynamic magnetic resonance imaging (MRI). Seven patients with the carcinoid syndrome and metastasized midgut carcinoid tumors underwent functional dynamic multi-phase gadolinium-enhanced MRI of selected liver metastases at baseline and 60 min after the subcutaneous (s.c.) administration of 100 microg octreotide, and also after 3 months with three times daily (t.i.d.) 100 microg octreotide s.c. Baseline MRIs showed the typical aspect of carcinoid liver metastases with a very bright signal on the T2-weighted sequences and intense enhancement in the arterial phase after injection of gadolinium-diethylenetriaminepentaacetate. MRIs 60 min after the s.c. administration of 100 microg octreotide showed a 34.9 +/- 6.2% (mean +/- SD) reduction in relative enhancement in the selected liver metastases as compared to baseline. In 2 patients, however, there was no (significant) reduction in the relative enhancement in the selected liver metastases 60 min after the s.c. administration of 100 microg octreotide as compared to baseline. Only in 2 patients did the MRIs at 3 months show a decrease in relative enhancement in one of the selected liver metastases. At 3 months, with 100 microg octreotide s.c. t.i.d., there was no correlation between the change in relative enhancement on MRI and the change in 24-hour 5-HIAA excretion. There is thus only an acute effect of octreotide on the perfusion of liver metastases. This study further shows that contrast-enhanced dynamic MRI can be a very useful tool for studying hemodynamic effects of medical therapies on liver metastases in patients with metastatic midgut carcinoids.