Portacaval shunt

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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.

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<span class="mw-page-title-main">Budd–Chiari syndrome</span> Medical condition

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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.

<span class="mw-page-title-main">Cirrhosis</span> Chronic disease of the liver, characterized by fibrosis

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.

<span class="mw-page-title-main">Hepatic hydrothorax</span> Medical condition

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.

References

  1. 1 2 Iwatsuki S (September 1974). "A case of hepatic encephalopathy after portacaval shunt". The Japanese Journal of Surgery. 4 (3): 183–188. doi:10.1007/bf02468624. PMID   4464374. S2CID   10001207.
  2. Sarfeh IJ, Rypins EB (April 1994). "Partial versus total portacaval shunt in alcoholic cirrhosis. Results of a prospective, randomized clinical trial". Annals of Surgery. 219 (4): 353–61. doi:10.1097/00000658-199404000-00005. PMC   1243151 . PMID   8161260.