azygos system and Hepatic Portal System

azygos system

system of veins that drains blood from intercostal area (thorax) and some of the blood below the diaphragm to the superior vena cava,

Is the azygos system a collateral system?

Yes, b/c it bypasses the inferior vena cava and instead drains into the superior vena cava

Azygos Vein

• right side, drains to Superior Vena Cava

Veins that drain into the Azygos Vein

Right side: right posterior intercostals veins

Left side: accessory hemiazygos vein and hemiazygous vein

Left posterior intercostals drain to

• Accessory Hemiazygous Veins (upper)

• Hemiazygous veins (lower)

Hepatic Portal System

a system of veins that carries blood from GI tract, spleen, pancreas, gallbladder, visceral fat to the liver before returning to heart

purpose of hepatic portal system

allows liver to:

1.) filter and process substances absorbed from food, protecting the body from toxins

2.) process and store nutrients

3.) remove bacteria

Characteristics of blood entering Hepatic Portal System

• low in oxygen

• high in nutrients

What happens in 1st capillary bed of Hepatic Portal System?

• nutrients and toxins absorbed by the capillaries

what happens in 2nd Capillary bed of Hepatic Portal System?

• nutrients and toxins leave the capillaries

what are the veins of the Hepatic Portal System (HPS)?

• hepatic portal vein

• splenic vein

• superior mesenteric

• inferior mesenteric

which veins anastomose to form the Hepatic Portal Vein?

• splenic vein (left side)

• superior mesenteric (right side)

where does the inferior mesenteric vein drain to?

• splenic vein

splenic veins serves which organs

• spleen, parts of pancreas and the stomach

what organs does the superior mesenteric vein serve?

• small intestines and part of the stomach and large intestines

what organs does the inferior mesenteric vein serve?

• distal part of large intestine and rectum

What vessels remove blood from the liver?

• hepatic veins

Where do the hepatic veins drain to

Inferior vena cava