Portal Hypertension

Question 1

What is the normal pressure of the hepatic portal vein and how does this change with portal hypertension?

Answer 1

Normal os between 5 and 8 mmHg

Portal hypertension occurs when the pressure rises above 10mmHg

Question 2

What are the three major complications which result from portal hypertension?

Answer 2

Varices (oesophageal)
Ascites
Splenomegaly

Question 3

What are some possible prehepatic causes if portal hypertension?

Answer 3

Portal vein thrombosis
Splenic vein thrombosis
Increased blood flow due to splenomegaly

Question 4

What are some common hepatic causes of portal hypertension?

Answer 4

Hepatitis

Cirrhosis

Question 5

What are some posthepatic causes of portal hypertension?

Answer 5

Right sided heart failure

Hepatic vein outflow obstruction

Question 6

Describe the consequences of the opening of shunt vessels in portal hypertension

Answer 6

Large collateral vessels open due to the increase in pressure in the hepatic portal vein. Some of these shunts develop between the portal vein and systemic veins in the lower rectum and oesophagus. The collaterals which form in the rectum can lead to haemorrhoids. In some people veins on the surface of the abdomen can be affected - this is called caput medusae. The most important of these shunts however are the ones at the oesophagus as varices here are particularly susceptible to rupture and cause severe and potentially fatal haemorrhage.

Question 7

How are oesophageal varices treated?

Answer 7

Pharmacological treatment to reduce blood flow such as beta blockers
Sclerotheraoy via an endoscope injects sclerosant into the varix to protect from rupture
More commonly banding (again by endoscopy) is used - a band is placed around the varix causing it to thrombose. The band then drops off.

Question 8

Balloon tamponade can be used in the management if acute haemorrhage of oesophageal varices. T/F?

Answer 8

True

Question 9

What is transjugular intrahepatic porotsystemic shunting?

Answer 9

TIPS is a long term management solution of portal hypertension whereby a stent is inserted between a branch of the hepatic vein and the hepatic portal vein using a catheter inserted via the internal jugular vein

Question 10

Splenomegaly occurs with portal hypertension due to the backing up of the flow of blood. How does this lead to thrombocytopaenia and leukaemia?

Answer 10

Splenomegaly leads to an increased rate of removal of these elements from the blood due to the prolonged transit time through the enlarged spleen and this causes a decrease in the lifespan of these cells and hence results in thrombocytopaenia and leukaemia.

Question 11

How does ascites develop?

Answer 11

An increase in hydrostatic pressure due to portal hypertension, salt and water retention by the kidney and decreased colloidal pressure by impaired synthesis of albumin in the liver all leads to the formation of ascites

Question 12

Spontaneous bacterial peritonitis and hepatic encephalopathy are rarer complications of portal hypertension. T/F?

Answer 12

True

Question 13

How is ascites managed?

Answer 13

Dietary restriction of sodium
Administration if diuretics
Restriction of water intake