Anatomy Overview II

Question 1

What is the arterial bloody supply to the foregut of the GI tract?

Answer 1

Foregut:

Coeliac Trunk (T12)

Main branches:

Left gastric artery (lesser curvature of stomach)

Hepatic artery (Liver and gallbladder)

Splenic artery (pancreas)

Question 2

What is the arterial supply to the midgut of the GI tract?

Answer 2

SMA (L1)

Main branches:

Jejunal artery

Ileal artery

Question 3

What is the arterial supply to the hindgut of the GI tract?

Answer 3

IMA (L3)

Main branches:

Left colic

Sigmoid arteries

Superior rectal artery

Question 4

What is the lymphatic drainage of the different parts of the gut tube and what is its clinical signficance?

Answer 4

Thoracic duct - receives most of the lymphatic drainage from abdominal wall and organs

Lympathic nodes form groups around the major arteries of the GI tract and abdominal aorta:

1) Pre-aortic group (ceoliac, superior and inferior mesenteric nodes)
2) Lateral aortic
3) Retro aortic (drains posterior abdominal wall)

Understanding Lympathic drainage of GI tract/organs is crucial for managing diseases such as cancer - especially the lymph nodes of the Stomach, Duodenum and Pancreas

Question 5

What is the portal venous system?

Answer 5

The portal system is a rich network of veins carrying nutrient (from digested food from small intestine) rich blood to the liver for processing

Question 6

What is the venous drainage of the GI tract?

Answer 6

SMA vein (drains into splenic vein)

IMA vein (drains into splenic vein)

The SMA + Splenic vein = Hepatic portal vein

Question 7

How can abdominal pain be referred?

Answer 7

The nerves which innervate an abdominal organ can also innervate distal areas of the body

This means that abdominal pain can be felt distant from the source of the pain

Question 8

How are abdominal organs innervated?

Answer 8

Vagus nerve:

Parasympathetic

Splanchnic nerve:

Sympathetic