Portal hypertension

Portal hypertension
Classification and external resources
The portal vein and its tributaries.
ICD-10	K76.6
ICD-9	572.3
DiseasesDB	10388
eMedicine	radio/570 med/1889
MeSH	D006975

In medicine, portal hypertension is hypertension (high blood pressure) in the portal vein and its tributaries.

It is often defined as a portal pressure gradient (the difference in pressure between the portal vein and the hepatic veins) of 5 mm Hg or greater.

Causes

Causes can be divided into prehepatic, intrahepatic, and posthepatic. Intrahepatic causes include liver cirrhosis, and hepatic fibrosis (e.g. due to Wilson's disease, hemochromatosis, or congenital fibrosis). Prehepatic causes include portal vein thrombosis or congenital atresia. Posthepatic obstruction occur at any level between liver and right heart, including hepatic vein thrombosis, IVC thrombosis, IVC congenital malformation, and constrictive pericarditis.

Signs and symptoms

Consequences of portal hypertension are caused by blood being forced down alternate channels by the increased resistance to flow through the portal system. They include:

• Ascites (free fluid in the peritoneal cavity)^[1]
• Hepatic encephalopathy
• Increased risk of spontaneous bacterial peritonitis
• Increased risk of hepatorenal syndrome
• Splenomegaly (enlargement of the spleen) with consequent sequestration therein of red blood cells, white blood cells, and platelets, together leading to mild pancytopenia
• Portacaval anastomoses (esophageal varices, gastric varices, hemorrhoids, caput medusae), with esophageal varices and gastric varices posing an ongoing risk of life-threatening hemorrhage, with haematemesis or melaena

Treatment

Prophylaxis of variceal bleeding

Both pharamacological(B-blocker and isosorbide mononitrate) and endoscopic(banding ligation) treatment have similar results. TIPS(transjugular intrahepatic portosystemic shunting) is superior to either of them at reducing rate of rebleeding. Disadvantages of TIPS include that it is costly, increase risk of hepatic encephalopathy and does not improve mortality.

Management of active variceal bleeding

After resuscitation, the management of active variceal bleeding include administering vasoactive drugs (octreotide and telipressin), endoscopic banding ligation, balloon tamponade and TIPS.

Management of ascites

This should be gradual to avoid sudden changes in systemic volume status which can precipitate hepatic encephalopathy, renal failure and death. The management include salt restriction, diuretics(spironlactone), paracentensis, TIPS and peritoneovenous shunt.

Control of hepatic encephalopathy

This include reduction of dietary protein, followed by lactulose, and use of oral antibiotics.

References

External links

• VIDEO - Portal Hypertension: Shunt Surgery in the Era of Transplant and TIPS, Alysandra Lal, MD, speaks at the University of Wisconsin School of Medicine and Public Health (2007)
• Ascites at Merck Manual of Diagnosis and Therapy Home Edition
• 00863 at CHORUS
• Overview at Cleveland Clinic
• Children's Liver Disease Foundation