Hepatic Portal Vein

Hepatic portal vein system, which is one of the main portal venous systems in the body, is a system of veins, responsible for directing blood from different parts of the gastrointestinal tract to the liver. It comprises the portal vein and its smaller tributaries. The hepatic portal system begins in the capillaries in the gastrointestinal tract and ends in the hepatic portal vein.

What is Hepatic Portal Vein?
Hepatic vein, often known as portal vein, is a short vein present in the abdominal cavity. It is formed by the confluence of the superior and the splenic veins. This vein is located in the right quadrant of the abdomen and measures about 3 inches in adults. It originates behind the neck of the pancreas, and ascends anterior to the inferior vena cava. At the right end of the porta hepatis, it divides into two branches which ramify within the liver forming several smaller venous branches and ultimately portal venules.

Function
The vein is responsible for draining blood from the gastrointestinal tract and spleen into the liver. It receives blood from the stomach, small intestine, large intestine, pancreas, spleen and gallbladder through the inferior mesenteric, gastric, and cystic veins. It carries the blood received from all these parts of the body to the liver. The blood that is brought to the liver by the portal vein is cleaned by the liver and flows into the inferior vena cava through the hepatic veins. It is then taken to the heart for systemic circulation. The blood coming from the different parts of the digestive system is fully loaded with nutrients and toxins that have been absorbed along the tract from the ingested food. The liver detoxifies the blood by filtering it and that is the main reason why the blood is brought to the liver by this vein. The blood can enter the systemic circulation of the body after all the toxins have been removed.

Thrombosis
This blond vessel is prone to developing a blood clot that causes obstruction in the normal blood flow and results in blocking the portal vein. The blood thus, backs up in the vein itself resulting in increased pressure in all the other veins below it. It even gets overfilled in the organs like the spleen, from which the portal vein collects blood. This condition is known as hepatic portal vein thrombosis. It gives rise to portal pressure and may result in several serious health hazards.

When the portal vein gets blocked and the blood is unable to flow normally, the body attempts to bypass the blocked vein by developing several thin walled veins or collaterals. These collaterals appear like varicosities and may appear anywhere in the abdomen but are generally seen at the lower end of the esophagus. The symptoms of acute hepatic vein thrombosis are vague and are often missed. However, in case of chronic thrombosis, the patient suffers from vomiting of bright red blood. Fluid accumulation in the abdomen along with confusion, loss of memory and coma may also be the symptoms of chronic vein thrombosis. There are chances of treating this condition effectively in absence of liver diseases or liver failure. But it can be fatal if the liver is damaged due to some other health problems.

So, this was all about the hepatic portal vein and its importance in the body. Hope you found this article informative!