Blood Supply

From what two sources does the liver receive blood?

From the hepatic artery proper (arterial oxygenated blood)

and the portal vein (venous nutrient-rich blood).

What proportion of blood enters the liver through each source?

About 80% through the portal vein

and 20% through the hepatic artery proper.

What are the branches of the hepatic artery?

Right gastric,

gastroduodenal,

cystic,

and direct branches to the bile duct.

Describe the course of the hepatic artery.

It passes anteriorly and laterally below the epiploic foramen to the upper aspect of the first part of the duodenum.

How is the hepatic artery subdivided?

Into the common hepatic artery (from celiac trunk to origin of gastroduodenal artery)

and the hepatic artery proper (from this point to its bifurcation).

Describe the path of the hepatic artery proper.

It passes anterior to the portal vein,

ascends between the two layers of the lesser omentum anterior to the epiploic foramen,

and divides at the porta hepatis into right and left branches.

Where does the portal vein begin and how is it formed?

It begins at the level of the second lumbar vertebra

and is formed by : superior mesenteric and splenic veins.

position of the portal vein?

lies anterior to the inferior vena cava,

and posterior to the neck of the pancreas.

Describe the course of the portal vein.

It ascends obliquely to the right behind the first part of the

duodenum,

the common bile duct,

and the gastroduodenal artery.

Where does the portal vein enter and end?

It enters the right border of the lesser omentum,

ascends anterior to the epiploic foramen to reach the porta hepatis,

and then divides into right and left branches.