The portal vein, which connects the intestines and the liver, supplies 75 percent of the liver's blood and 60 percent of its oxygen.
Portal hypertension is defined as blood pressure in the portal vein that exceeds 5 to 10 millimeters of mercury (mm Hg).
The increase in portal vein pressure is caused by buildup of scar tissue in a damaged liver.
Portal hypertension is high blood pressure in the portal vein, the blood vessel that connects the intestines and the liver. The condition usually develops in people who have liver damage. Scar tissue in the liver interrupts normal blood flow, causing blood to back up into the portal vein and increasing blood pressure.
This backup causes the blood to force its way into tiny, thin-walled veins at the base of the esophagus and in the stomach. These fragile blood vessels, known as varices, become stretched, swollen, and twisted and in danger of breaking and bleeding.
WHAT ARE THE SYMPTOMS?
By itself, portal hypertension has no symptoms. The following complications of portal hypertension, however, cause symptoms:
Bloody vomiting, and
Black, loose stools.
The accumulation of fluid in the abdomen (ascites) occurs when a liver becomes so damaged that it can no longer make the protein albumin, which holds fluid inside blood vessels.
When the brain is exposed to toxins such as ammonia that a damaged liver cannot clear from the body, a brain disease called encephalopathy results. Signs of encephalopathy include:
Neglect of personal appearance;
CAUSES AND RISK FACTORS
People who have portal hypertension also have a damaged liver. The causes of a damaged liver include:
Chronic viral hepatitis;
Various congenital disorders; and
Primary biliary cirrhosis, an autoimmune disease.
Portal hypertension is assumed if a person with liver disease also has ascites, varices, or encephalopathy.
To confirm a diagnosis, a physician may order one or more of the following tests:
Computed tomography (CT) scan;
Endoscopy (physicians insert a viewing tube called an endoscope through the mouth and down into the beginning of the small intestine).
The distal splenorenal shunt procedure alters blood flow to the portal vein in a way that reduces blood pressure on varices.
Treatment for portal hypertension often begins when varices bleed severely. Patients who experience this medical emergency may receive the following:
Blood transfusions; and
Emergency endoscopy to confirm the source of the bleeding.
Once the bleeding is located, physicians use one of the following endoscopic techniques to remove the varices:
Latex banding; or
Along with these endoscopic therapies, patients receive intravenous blood pressure-lowering medications, such as:
When endoscopic treatments cannot treat varices effectively, physicians may implant a stent, or a thin mesh-metal tube, to reroute blood and relieve pressure on the portal vein.
To treat ascites, physicians recommend lifestyle changes and over-the-counter treatments, such as:
Eating a low-sodium diet; and
Taking diuretics to remove fluid from the body. If the abdomen is extremely swollen, physicians may order a paracentesis (the insertion of a catheter into the abdominal wall to drain excess fluid.)
To treat encephalopathy, a physician may recommend one or more of the following:
Substituting vegetable protein for animal protein; or
Laxatives, lactalose, and antibiotics (medications that remove toxins from the intestines).
Patients become candidates for a liver transplant when they have portal hypertension with variceal bleeding and end-stage liver disease.