Portal Hypertension

Question 1

What is portal hypertension

Answer 1

It refers to elevated pressures in the portal venous system
It occurs when pressure in the venous system is 5 mmhggreater than pressure in the inferior vend cava
It results from a functional obstruction to blood flow from any point in portal system’s origin (in the splanchnic bed ) through the hepatic veins (exit into the systemic circulation) or from an increase in blood flow in the system

Question 2

What are the causes of PH

Answer 2

1. Suprahepatic= obstruction of low beyond the liver
2. hepatic= obstruction of flow within the liver
3. infrahepatio = obstruction of flow prior to entrance into the liver

Question 3

Causes of supralhepatic hypertension

Answer 3

Cardiac disease
Hepatic vein ethology
Inferior vena cava thrombosis
Hepatic vein thrombosis or budd-chiari syndrome, has multiple etiologies but is generally related to a hypercoagulable state

Question 4

Causes of hepatic portal hypertension

Answer 4

1. Cirrhosis is the most common (which is caused by chronic viral hepatitis C ) other causes of cirrhosis are alcohol induced liver disease and cholestatic liver diseases
2. Hemochromatosis
3. Alpha1 antitrypsin deficiency
4. Hepatitis B

Question 5

Causes of infrahepatic causes

Answer 5

1. Alterations of portal venous blood flow
2. Arteriovencus malformation of the splenic vasculature
3. Splenomegaly
4. Portal vein thrombosis

Question 6

The effects of cytokines

Answer 6

Cytokines such as tumour necrosis factor alpha (tne-alpha) and others may play a role In stimulating endothelial vasodilator such as nitric oxide and prostacyclin as well as non endothelial vasodialators like glucagon
These molecules may affect pressure and flow in splanchnic vasculature