Portal hypertension

The joining of the splenic and superior mesenteric vein forms the portal vein. The upper limit of portal venous pressure is 10mmHg with normal portal venous pressure being between 4-8 mmHg. Chronic liver disease leads to the obstruction of intrahepatic veins and raises portal venous pressure. Causes, as with most organ obstruction, can be classified as prehepatic, hepatic and post hepatic.

Prehepatic

• Splenic or portal vein thrombosis
• Splenic AV fistula
• Massive splenomegaly

Hepatic

• Alcoholic liver disease
• Chronic viral hepatitis, usually B, C or D
• Cirrhosis
• Early primary biliary cirrhosis
• Myeloproliferative disorders
• Sarcoidosis
• Schistosomiasis

Post-hepatic

• Right heart failure
• Budd-Chiari (hepatic vein thrombosis and in 10-20% the portal vein is thrombosed)
• Constrictive pericarditis

Child's classification

AKA Child-Pugh and Child-Turcotte-Pugh score. Originally a score to predict mortality after surgery. Now used to determine prognosis, treatment and need for liver transplantation. Each item has a score of 1-3 so a score of 5-15 is obtained.

1. Serum bilirubin (ranges adjusted in primary sclerosing cholangitis and primary biliary cirrhosis to account for higher levels seen)
2. Serum albumin
3. Ascites
4. Hepatic encephalopathy
5. Prothrombin time (Pugh). INR now more commonly used

Patients are graded into three classes.

Varices

Distension of portasystemic venous anastomosis that are pre-existing and normally microscopic. They occur in a number of sites but probably the most serious are the lower oesophageal wall ones i.e. the communications between the left gastric (portal system) and the azygous (systemic) veins.

Others: