A portacaval shunt, portocaval shunt, or portal-caval shunt is a treatment for portal hypertension. A connection (a shunt) is made between the portal vein, which supplies 75% of the liver's blood, and the inferior vena cava, the vein that drains blood from the lower two-thirds of the body. The most common causes of liver disease resulting in portal hypertension are Budd–Chiari syndrome or cirrhosis. Budd–Chiari syndrome should not be mistaken for cirrhosis.
Less common causes include diseases such as hemochromatosis, primary biliary cirrhosis (PBC), and portal vein thrombosis.[ citation needed ]
Cirrhotic patients often develop hepatic encephalopathy (HE) following the procedure, [1] sometimes resulting in coma. [2] The high risk of developing HE may be a consequence of increased intestinal absorption of encephalopathogenic substances in combination with the reduced hepatic blood flow. [1]
A portacaval anastomosis is analogous in that it diverts circulation; as with shunts and anastomoses generally, the terms are often used to refer to either the naturally occurring forms or the surgically created forms.
Ascites is the abnormal build-up of fluid in the abdomen. Technically, it is more than 25 ml of fluid in the peritoneal cavity, although volumes greater than one liter may occur. Symptoms may include increased abdominal size, increased weight, abdominal discomfort, and shortness of breath. Complications can include spontaneous bacterial peritonitis.
The portal vein or hepatic portal vein (HPV) is a blood vessel that carries blood from the gastrointestinal tract, gallbladder, pancreas and spleen to the liver. This blood contains nutrients and toxins extracted from digested contents. Approximately 75% of total liver blood flow is through the portal vein, with the remainder coming from the hepatic artery proper. The blood leaves the liver to the heart in the hepatic veins.
Budd–Chiari syndrome is a very rare condition, affecting one in a million adults. The condition is caused by occlusion of the hepatic veins that drain the liver. It presents with the classical triad of abdominal pain, ascites, and liver enlargement. The formation of a blood clot within the hepatic veins can lead to Budd–Chiari syndrome. The syndrome can be fulminant, acute, chronic, or asymptomatic. Subacute presentation is the most common form.
Esophageal varices are extremely dilated sub-mucosal veins in the lower third of the esophagus. They are most often a consequence of portal hypertension, commonly due to cirrhosis. People with esophageal varices have a strong tendency to develop severe bleeding which left untreated can be fatal. Esophageal varices are typically diagnosed through an esophagogastroduodenoscopy.
Portal hypertension is abnormally increased portal venous pressure – blood pressure in the portal vein and its branches, that drain from most of the intestine to the liver. Portal hypertension is defined as a hepatic venous pressure gradient greater than 5 mmHg. Cirrhosis is the most common cause of portal hypertension; other, less frequent causes are therefore grouped as non-cirrhotic portal hypertension. When it becomes severe enough to cause symptoms or complications, treatment may be given to decrease portal hypertension itself or to manage its complications.
Liver disease, or hepatic disease, is any of many diseases of the liver. If long-lasting it is termed chronic liver disease. Although the diseases differ in detail, liver diseases often have features in common.
Hepatic encephalopathy (HE) is an altered level of consciousness as a result of liver failure. Its onset may be gradual or sudden. Other symptoms may include movement problems, changes in mood, or changes in personality. In the advanced stages it can result in a coma.
Hepatorenal syndrome is a life-threatening medical condition that consists of rapid deterioration in kidney function in individuals with cirrhosis or fulminant liver failure. HRS is usually fatal unless a liver transplant is performed, although various treatments, such as dialysis, can prevent advancement of the condition.
Transjugular intrahepatic portosystemic shunt is an artificial channel within the liver that establishes communication between the inflow portal vein and the outflow hepatic vein. It is used to treat portal hypertension which frequently leads to intestinal bleeding, life-threatening esophageal bleeding and the buildup of fluid within the abdomen (ascites).
Portal vein thrombosis (PVT) is a vascular disease of the liver that occurs when a blood clot occurs in the hepatic portal vein, which can lead to increased pressure in the portal vein system and reduced blood supply to the liver. The mortality rate is approximately 1 in 10.
Gastric antral vascular ectasia (GAVE) is an uncommon cause of chronic gastrointestinal bleeding or iron deficiency anemia. The condition is associated with dilated small blood vessels in the pyloric antrum, which is a distal part of the stomach. The dilated vessels result in intestinal bleeding. It is also called watermelon stomach because streaky long red areas that are present in the stomach may resemble the markings on watermelon.
A portosystemic shunt or portasystemic shunt, also known as a liver shunt, is a bypass of the liver by the body's circulatory system. It can be either a congenital or acquired condition and occurs in humans as well as in other species of animals. Congenital PSS are extremely rare in humans but are relatively common in dogs. Thus a large part of medical and scientific literature on the subject is grounded in veterinary medicine.
In medicine, a distal splenorenal shunt procedure (DSRS), also splenorenal shunt procedure and Warren shunt, is a surgical procedure in which the distal splenic vein is attached to the left renal vein. It is used to treat portal hypertension and its main complication. It was developed by W. Dean Warren.
A portacaval anastomosis or portocaval anastomosis is a specific type of circulatory anastomosis that occurs between the veins of the portal circulation and the vena cava, thus forming one of the principal types of portasystemic anastomosis or portosystemic anastomosis, as it connects the portal circulation to the systemic circulation, providing an alternative pathway for the blood. When there is a blockage of the portal system, portocaval anastomosis enables the blood to still reach the systemic venous circulation. The inferior end of the esophagus and the superior part of the rectum are potential sites of a harmful portocaval anastomosis.
The serum-ascites albumin gradient or gap (SAAG) is a calculation used in medicine to help determine the cause of ascites. The SAAG may be a better discriminant than the older method of classifying ascites fluid as a transudate versus exudate.
Hepatic veno-occlusive disease (VOD) or veno-occlusive disease with immunodeficiency is a potentially life-threatening condition in which some of the small veins in the liver are obstructed. It is a complication of high-dose chemotherapy given before a bone marrow transplant and/or excessive exposure to hepatotoxic pyrrolizidine alkaloids. It is classically marked by weight gain due to fluid retention, increased liver size, and raised levels of bilirubin in the blood. The name sinusoidal obstruction syndrome (SOS) is preferred if hepatic veno-occlusive disease happens as a result of chemotherapy or bone marrow transplantation.
Cirrhosis, also known as liver cirrhosis or hepatic cirrhosis, and end-stage liver disease, is the impaired liver function caused by the formation of scar tissue known as fibrosis due to damage caused by liver disease. Damage causes tissue repair and subsequent formation of scar tissue, which over time can replace normal functioning tissue, leading to the impaired liver function of cirrhosis. The disease typically develops slowly over months or years. Early symptoms may include tiredness, weakness, loss of appetite, unexplained weight loss, nausea and vomiting, and discomfort in the right upper quadrant of the abdomen. As the disease worsens, symptoms may include itchiness, swelling in the lower legs, fluid build-up in the abdomen, jaundice, bruising easily, and the development of spider-like blood vessels in the skin. The fluid build-up in the abdomen may become spontaneously infected. More serious complications include hepatic encephalopathy, bleeding from dilated veins in the esophagus, stomach, or intestines, and liver cancer.
Hepatic hydrothorax is a rare form of pleural effusion that occurs in people with liver cirrhosis. It is defined as an effusion of over 500 mL in people with liver cirrhosis that is not caused by heart, lung, or pleural disease. It is found in 5-10% of people with liver cirrhosis and 2-3% of people with pleural effusions. It is much more common on the right side, with 85% of cases occurring on the right, 13% on the left, and 2% in both. Although it is most common in people with severe ascites, cases have been reported where people only had mild or no ascites. Symptoms are not specific, and mostly involve the respiratory system.
Congenital portosystemic shunts (PSS) is a hereditary condition in dogs and cats, its frequency varying depending on the breed. The shunts found mainly in small dog breeds such as Shih Tzus, Tibetan Spaniels, Miniature Schnauzers and Yorkshire Terriers, and in cats such as Persians, British Shorthairs, Himalayans, and mixed breeds are usually extrahepatic, while the shunts found in large dog breeds such as Irish Wolfhounds and Labrador Retrievers tend to be intrahepatic.