Portal vein blood contains nutrients and toxins extracted from digested contents, which the liver filters and processes.
Toxins are discarded as waste, while nutrients are broken down for use in the body.
The liver has a dual blood supply derived from the portal vein and thehepatic artery.
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The liver helps metabolize carbohydrates, proteins, and fats in the body.
Smaller veins from the stomach and pancreas also contribute to portal vein blood flow.
This then travels within thehepatoduodenalligament toward the portion of the liver called the liver hilum.
There, the vein splits into the right and left portal vein branches.
These enter the main section of the liver.
The right and left portal veins then branch further to supply the different lobes of the liver.
Most veins in the body, called systemic veins, carry blood toward the heart.
The portal vein and its contributing veins are different because they carry blood to the liver first.
Collectively, these veins are called the hepatic portal venous system.
If you have chronic liver disease, this system is at risk for serious complications.
Rarely, children may be born with an absent or underdeveloped portal vein.
The location of the shunts also affects your overall health.
The condition can sometimes be managed with medications or minimally invasive surgical procedures.
In severe cases, a liver transplant may be necessary.
One issue isascites, the build-up of fluid in the abdominal cavity.
Cirrhosiscauses pressure to be exerted on the portal venous; it also causes sodium retention.
In severe cases, hepatic encephalitis can affect consciousness.
This condition increases pressure on the vein and forces blood away from the liver.
Toxic substancesnormally processed by the liverare allowed to circulate throughout the body.
This affects brain function.
Portal Hypertension
Liver cirrhosis and other chronic liver diseases may disrupt blood flow in the portal vein.
This state is calledportal hypertension.
Abnormal connections (portosystemiccollaterals) form between the portal venous system and the systemic veins.
Large portosystemic collaterals around the stomach and esophagus (calledvarices) can cause gastrointestinal bleeding that may be life-threatening.
Portal Vein Thrombosis
Portal hypertension can also be sparked by clots forming in the portal vein.
This is called portal vein thrombosis.
Treatment of Portal Vein Disorders
Treating portal vein disorders starts with treating the underlying issue.
In cases of cirrhosis, the source of the cirrhosis must be eliminated.
Thus, you may need to abstain completely from alcohol or undergo special treatment for a virus.
These changes can ease symptoms significantly.
Medications may also reduce blood flow into portosystemic collaterals or reduce blood flow within the liver.
Your healthcare provider may recommend stopping or switching a medication.
Portal vein blood contains both nutrients and toxins derived from digestion, which the liver filters and processes.
Because of its location, cirrhosis and liver disease have the greatest impact on the portal vein.
These diseases can change the portal structure and reduce the flow of blood into the liver.
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