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Portal hypertension http://www.indiasurgeons.com/port_ht.htm 1: varices J E J Krige, I J Beckingham.  The portal vein carries about 1500 ml/min of blood from the small and large bowel, spleen, and stomach to the liver at a pressure of 5-10 mm Hg. Any obstruction or increased resistance to flow or, rarely, pathological increases in portal blood flow may lead to portal hypertension with portal pressures over 12 mm Hg. Although the differential diagnosis is extensive, alcoholic and viral cirrhosis are the leading causes of portal hypertension in Western countries, whereas liver disease due to schistosomiasis is the main cause in other areas of the world. Portal vein thrombosis is the commonest cause in children. Increases in portal pressure cause development of a portosystemic collateral circulation with resultant compensatory portosystemic shunting and disturbed intrahepatic circulation. These factors are partly responsible for the important complications of chronic liver disease, including variceal bleeding, hepatic encephalopathy, ascites, hepatorenal syndrome, recurrent infection, and abnormalities in coagulation. Variceal bleeding is the most serious complication and is an important cause of death in patients with cirrhotic liver disease. Causes of portal hypertension Increased resistance to flow Prehepatic (portal vein obstruction) Congenital atresia or stenosis Thrombosis of portal vein Thrombosis of splenic vein Extrinsic compression (for example, tumours) Hepatic Cirrhosis Acute alcoholic liver disease Congenital hepatic fibrosis Idiopathic portal hypertension (hepatoportal sclerosis) Schistosomiasis Posthepatic Budd-Chiari syndrome Constrictive pericarditis Increased portal blood flow Arterial-portal venous fistula Increased splenic flow Varices In Western countries variceal bleeding accounts for about 7% of episodes of gastrointestinal bleeding, although this varies according to the prevalence of alcohol related liver disease (11% in the United States, 5% in the United Kingdom). Patients with varices have a 30% lifetime risk of bleeding, and a third of those who bleed will die. Patients who have bled once from oesophageal varices have a 70% chance of bleeding again, and about a third of further bleeding episodes are fatal. Several important considerations influence choice of treatment and prognosis. These include the natural course of the disease causing portal hypertension, location of the bleeding varices, residual hepatic function, presence of associated systemic disease, continuing drug or alcohol misuse, and response to specific treatment. The modified Child-Pugh classification identifies three risk categories that correlate well with survival. Initial measures Prompt resuscitation and restoration of circulating blood volume is vital and should precede any diagnostic studies. While their blood is being cross matched, patients should receive a rapid infusion of 5% dextrose and colloid solution until blood pressure is restored and urine output is adequate. Saline infusions may aggravate ascites and must be avoided. Patients who are haemodynamically unstable, elderly, or have concomitant cardiac or pulmonary disease should be monitored by using a pulmonary artery catheter as injudicious administration of crystalloids, combined with vasoactive drugs, can lead to the rapid onset of oedema, ascites, and hyponatraemia. Concentrations of clotting factors are often low, and fresh blood, fresh frozen plasma, and vitamin K1 (phytomenadione) should be given. Platelet transfusions may be necessary. Sedatives should be avoided, although haloperidol is useful in patients with symptoms of alcohol withdrawal. Child-Pugh classification of liver failure       No of points   1 2 3 Bilirubin (µmol/l) <34 34-51 >51 Albumin (g/l) >35 28-35 <28 Prothrombin time <3 3-10 >10 Ascites None Slight Moderate to severe Encephalopathy None Slight Moderate to severe Grade A=5-6 points, grade B=7-9 points, grade C=10-15 points. Pharmacological control Drug treatment, aimed at controlling the acute bleed and facilitating diagnostic endoscopy and emergency sclerotherapy, may be useful when variceal bleeding is rapid. Octreotide, a synthetic somatostatin analogue, reduces splanchnic blood flow when given intravenously as a constant infusion (50 µg/h) and can be used before endoscopy in patients with active bleeding. Vasopressin (0.4 units/min), or the long acting synthetic analogue terlipressin, combined with glyceryl trinitrate administered intravenously or transdermally through a skin patch is also effective but has more side effects than octreotide. Glyceryl trinitrate reduces the peripheral vasoconstriction caused by vasopressin and has an additive effect in lowering portal pressure. Emergency Endoscopy Emergency diagnostic fibreoptic endoscopy is essential to confirm that oesophageal varices are present and are the source of bleeding. Most patients will have stopped bleeding spontaneously before endoscopy (60% of bleeds) or after drug treatment. Endotracheal intubation may be necessary during endoscopy, especially in patients who are bleeding heavily, encephalopathic, or unstable despite vigorous resuscitation. In 90% of patients variceal bleeding originates from oesophageal varices. These are treated by injection with sclerosant or by banding. Sclerotherapy In sclerotherapy a sclerosant solution (ethanolamine oleate or sodium tetradecyl sulphate) is injected into the bleeding varix or the overlying submucosa. Injection into the varix obliterates the lumen by thrombosis whereas injection into the submucosa produces inflammation followed by fibrosis. The first injection controls bleeding in 80% of cases. If bleeding recurs, the injection is repeated. Complications are related to toxicity of the sclerosant and include transient fever, dysphagia and chest pain, ulceration, stricture, and (rarely) perforation. Band ligation Band ligation is achieved by a banding device attached to the tip of the endoscope. The varix is aspirated into the banding chamber, and a trip wire dislodges a rubber band carried on the banding chamber, ligating the entrapped varix. One to three bands are applied to each varix, resulting in thrombosis. Band ligation eradicates oesophageal varices with fewer treatment sessions and complications than sclerotherapy. Balloon tube tamponade The balloon tube tamponade may be life saving in patients with active variceal bleeding if emergency sclerotherapy or banding is unavailable or not technically possible because visibility is obscured. In patients with active bleeding, an endotracheal tube should be inserted to protect the airway before attempting to place the oesophageal balloon tube. The Minnesota balloon tube has four lumens, one for gastric aspiration, two to inflate the gastric and oesophageal balloons, and one above the oesophageal balloon for suction of secretions to prevent aspiration. The tube is inserted through the mouth, and correct siting within the stomach is checked by auscultation while injecting air through the gastric lumen. The gastric balloon is then inflated with 200 ml of air. Once fully inflated, the gastric balloon is pulled up against the oesophagogastric junction, compressing the submucosal varices. The tension is maintained by strapping a split tennis ball to the tube at the patient's mouth. The oesophageal balloon is rarely required. The main complications are gastric and oesophageal ulceration, aspiration pneumonia, and oesophageal perforation. Continued bleeding during balloon tamponade indicates an incorrectly positioned tube or bleeding from another source. After resuscitation, and within 12 hours, the tube is removed and endoscopic treatment repeated. Transjugular intrahepatic portosystemic shunt Transjugular intrahepatic portosystemic shunt is the best procedure for patients whose bleeding is not controlled by endoscopy. It is effective only in portal hypertension of hepatic origin. The procedure is performed via the internal jugular vein under local anaesthesia with sedation. The hepatic vein is cannulated and a tract created through the liver parenchyma from the hepatic to the portal vein, with a needle under ultrasonographic and fluoroscopic guidance. The tract is dilated and an expandable metal stent inserted to create an intrahepatic portosystemic shunt. The success rate is excellent. Haemodynamic effects are similar to those found with surgical shunts, with a lower procedural morbidity and mortality. Transjugular intrahepatic portosystemic shunting is an effective salvage procedure for stopping acute variceal haemorrhage, controlling bleeding from gastric varices, and congestive gastropathy after failure of medical and endoscopic treatment. However, because encephalopathy occurs in up to 25% of cases and up to 50% of shunts may occlude by one year, its primary role is to rescue failed endoscopy or as a bridge to subsequent liver transplantation. Long term management After the acute variceal haemorrhage has been controlled, treatment should be initiated to prevent rebleeding, which occurs in most patients. Repeated endoscopic treatment Repeated endoscopic treatment eradicates oesophageal varices in most patients, and provided that follow up is adequate serious recurrent variceal bleeding is uncommon. Because the underlying portal hypertension persists, patients remain at risk of developing recurrent varices and therefore require lifelong regular surveillance endoscopy. Options for long term management Repeated endoscopic treatment Long term beta blockers Surgical shunt Liver transplantation Long term drug treatment The use of  blockers after variceal bleeding has been shown to reduce portal blood pressures and lower the risk of further variceal bleeding. All patients should take  blockers unless they have contraindications. Best results are obtained when portal blood pressure is reduced by more than 20% of baseline or to below 12 mm Hg. Surgical procedures Patients with good liver function in whom endoscopic management fails or who live far from centres where endoscopic sclerotherapy services are available are candidates for surgical shunt procedures. A successful portosystemic shunt prevents recurrent variceal bleeding but is a major operation that may cause further impairment of liver function. Partial portacaval shunts with 8 mm interposition grafts are equally effective to other shunts in preventing rebleeding and have a low rate of encephalopathy. Oesophageal transection and gastric devascularisation are now rarely performed but have a role in patients with portal and splenic vein thrombosis who are unsuitable for shunt procedures and continue to have serious variceal bleeding despite endoscopic and drug treatment. Liver transplantation is the treatment of choice in advanced liver disease. Hepatic decompensation is the ultimate decompressive shunt for portal hypertension and also restores liver function. Transplantation treats other complications of portal hypertension and has one year and five year survival rates of 80% and 60% respectively. Prophylaxis Most patients with portal hypertension never bleed, and it is difficult to predict who will. Attempts at identifying patients at high risk of variceal haemorrhage by measuring the size or appearance of varices have been largely unsuccessful. Beta blockers have been shown to reduce the risk of bleeding, and all patients with varices should take them unless contraindicated. Summary points Variceal bleeding is an important cause of death in cirrhotic patients Acute management consists of resuscitation and control of bleeding by sclerotherapy or balloon tamponade After a bleed patients require treatment to eradicate varices and lifelong surveillance to prevent further bleeds All patients with varices should take Beta blockers to reduce the risk of bleeding unless contraindicated by coexisting medical conditions Surgery is now rarely required for acute or chronic control of variceal bleeding Gastirc varices Gastric varices are the source of bleeding in 5-10% of patients with variceal haemorrhage. Higher rates are reported in patients with left sided portal hypertension due to thrombosis of the splenic vein. Endoscopic control of gastric varices is difficult unless they are located on the proximal lesser curve in continuation with oesophageal varices. Endoscopic administration of cyanoacrylate monomer (superglue) is useful for gastric varices. The transjugular intrahepatic portosystemic shunt is increasingly used to control bleeding in this group. Bleeding from portal hypertensive gastropathy accounts for 2-3% of bleeding episodes in cirrhosis. Although serious bleeding from these sources is uncommon, when it occurs its diffuse nature precludes the use of endoscopic treatment, and optimal management is with a combination of terlipressin and Beta blockers. Variceal Bleeding Management Procedures What is portal hypertension and variceal bleeding? The variceal bleeding you have had is caused by portal hypertension. Portal hypertension is an increase in the pressure within the portal vein (the vein that carries blood from the digestive organs to the liver). This increase in pressure is caused by a blockage in the blood flow throughout the liver. Increased pressure in the portal vein causes large veins (varices) to develop across the esophagus and stomach to bypass the blockage. The varices become fragile and can bleed easily. Symptoms of portal hypertension include: Bleeding -- black stools and/or vomiting of blood due to the spontaneous rupture and hemorrhage from varices Ascites -- an accumulation of fluid in the abdomen Encephalopathy -- confusion and forgetfulness caused by poor liver function and the diversion of blood flow away from your liver Endoscopy, X-ray studies and lab work confirm that you have variceal bleeding. Further treatment is necessary to reduce the risk of rebleeding. How is variceal bleeding treated? Once the bleeding episode has been stabilized, treatment options are prescribed based on the severity of your symptoms and how well your liver is functioning. First level of treatment When you were first diagnosed with variceal bleeding, you may have been treated with endoscopic therapy and/or medications. Endoscopic therapy consists of either sclerotherapy or banding. Medications such as beta blockers or nitrates may have been prescribed alone or in combination with endoscopic therapy to reduce the pressure in your varices and further reduce the risk of rebleeding. Because the first level of treatment has not successfully controlled your variceal bleeding, you now require decompression (reducing the pressure) of your varices. Second level of treatment Two procedures for decompression are: Transjugular Intrahepatic Porto systemic Shunt (TIPS) -- a radiological procedure in which a stent (a tubular device) is placed in the middle of the liver to reroute the blood flow Distal Splenorenal Shunt (DSRS) -- a surgical procedure that connects the splenic vein to the left kidney vein NIH study comparing the TIPS and DSRS procedures By decreasing the pressure (decompression) in your veins, either the TIPS or DSRS procedure can provide control of your bleeding. There are advantages and disadvantages of both procedures. Neither procedure has been proven to be a better treatment for long-term control of bleeding, or for the overall management of patients with cirrhosis and portal hypertension. A study directly comparing both procedures is now being funded by the National Institute of Health (NIH). This study is being conducted at several medical facilities. Since endoscopic therapy and medications are no longer controlling your bleeding, we encourage you to participate in this study. What is the TIPS procedure? During the TIPS procedure, a radiologist makes a tunnel through the liver with a needle, connecting the portal vein (the vein that carries blood from the digestive organs to the liver) to one of the hepatic veins (the three veins that carry blood from the liver). A metal stent is placed in this tunnel to keep the track open. The TIPS procedure reroutes blood flow in the liver and reduces pressure in all abnormal veins, not only in the stomach and esophagus, but also in the bowel and the liver. The TIPS procedure is not a surgical procedure -- the radiologist performs the procedure within the vessels in the X-ray room under X-ray guidance. The procedure lasts 1 to 3 hours. You should expect to stay in the hospital 2 to 3 days after the procedure. The TIPS procedure controls bleeding immediately in over 90% of patients, but has a late rebleeding rate of about 20% because the shunt may narrow. What are the potential complications of the TIPS procedure? Shunt narrowing or occlusion (blockage) -- this could happen within the first year after the procedure. Follow-up ultrasounds are performed frequently after the TIPS procedure to detect these complications. The signs of occlusion include increased ascites or rebleeding. This condition can be treated by a radiologist who re-expands the shunt with a balloon or repeats the procedure to place a new stent. Encephalopathy -- mental changes caused by abnormal functioning of the brain that occur with severe liver disease. Encephalopathy can be worse when blood flow to the liver is reduced by TIPS, which may result in toxic substances reaching the brain without being metabolized first by the liver. This condition can be treated with medications, diet or by revising the shunt. What is the DSRS procedure? The DSRS is a surgical procedure. During the surgery, the vein from the spleen (called the splenic vein) is detached from the portal vein and reattached to the left kidney (renal) vein. This surgery selectively reduces the pressure in your varices and controls the bleeding. Figure 3 illustrates the distal splenorenal shunt procedure. A general anesthetic is given to you before the surgery. The surgery lasts about 4 hours. You should expect to stay in the hospital from 7 to 10 days. DSRS controls bleeding in over 90% of patients, with the highest risk of any rebleeding in the first month. However, the DSRS procedure provides good long-term control of bleeding. What is the potential complication of the DSRS surgery? Ascites -- an accumulation of fluid in the abdomen. This condition can be treated with medications called diuretics and restricted sodium intake. What tests are required before the TIPS and DSRS procedures? Before these procedures, you will have had the following tests to determine the extent and severity of your portal hypertension condition: Evaluation of your medical history A physical examination Blood tests Galactose liver function test Angiogram Ultrasound Endoscopy Before either the TIPS or DSRS procedure, your physician may ask you to come to the Clinic for pre-operative tests. The tests may include an electrocardiogram (also called an EKG), chest x-ray or additional blood tests. If your physician thinks you will need additional blood products (such as plasma), they will be ordered at this time. Follow-up medical care for both procedures Ten days after your hospital discharge date, you will meet with the surgeon or hepatologist and nurse coordinator to evaluate your progress. Lab work will be done at this time. Six weeks after the TIPS procedure (and again 3 months after the procedure), you will have an ultrasound so your physician can check that the shunt is functioning properly. You will have an angiogram only if the ultrasound indicates that there is a problem. You will also have lab work done at these times and visit the surgeon or hepatologist and nurse coordinator. Six weeks after the DSRS procedure (and again 3 months after the procedure), you will meet with the surgeon and nurse coordinator to evaluate your progress. Lab work will be done at this time. Six months after either the TIPS or DSRS procedure, you will have an ultrasound to make sure the shunt is working properly. You will also visit the surgeon or hepatologist and nurse coordinator to evaluate your progress. Lab work and a galactose liver function test will also be done at this time. Twelve months after either procedure, you will have another ultrasound of the shunt. You will also have an angiogram so your physician can check the pressure within your veins across the shunt. You will meet with the surgeon or hepatologist and the nurse coordinator. Lab work and a galactose liver function test will be done at this time. If the shunt is working well, every 6 months after the first year of follow-up appointments you will have an ultrasound, lab work and you will visit with your physician and nurse coordinator. More frequent follow-up visits may be necessary, depending on your condition. What do I need to do to maintain my health after these procedures? Attend all follow-up appointments, as scheduled, to ensure that the shunt is properly functioning. Be sure to follow the dietary recommendations provided by your health care providers.