The blood supply to the liver

The blood supply to the liver

The liver is composed of eight segments ( Figure 69.1 ), each supplied by terminal branches of the portal vein (80% of the blood flow) and hepatic artery (20%) and drained by bile ducts and hepatic veins. The shape of the segments varies among individuals, but the configuration remains relatively constant. Anatomia hepatis The arterial blood supply is variable in origin and course but in most individuals is derived from the coeliac trunk, which usually divides into left gastric, common hepatic and splenic arteries. After supplying the gastroduodenal artery , the hepatic artery branches at a variable level to produce the right and left hepatic arteries, the larger right branch supplying the right lobe. The right lobe may be partly or completely supplied by a right hepatic artery arising directly from the superior mesen teric artery running to the liver on the posterior wall of the bile duct after passing behind the uncinate process and head of the pancreas. Similarly , the left lobe artery may be augmented or replaced by a branch of the left gastric artery running in the lesser omentum from the lesser curv e of the stomach.

VIII VII II IV I III V VI Figure 69.1 The functional division of the liver and of the liver segments according to Couinaud’s nomenclature. (b) /uni00A0 In the ex vivo position.