The Blood supply to the gut Flashcards
What are the 3 unpaired arteries that supply the gut
Coeliac (T12)
superior mesenteric artery (L1)
inferior mesenteric artery (L3)
What supplies the foregut
coeliac trunk (T12)
what supplies the midgut
superior mesenteric artery (L1)
what supplies the handout
inferior mesenteric artery (L3)
What are the other paired abdominal artery
- renal
- gonadal
- lumbar
where does the aortic bifurcation happen
Aortic bifurcation into common iliac happens at L4
what are the 3 arteries that the coeliac trunk split into
- Left gastric
- Splenic
- Common hepatic
describe the left gastric artery
- Left gastric artery course around the inferior curvature of the stomach, it also gives of oesophageal arteries as well
- In terms of the stomach it supplies the lesser curvature of the stomach, it is joined by the right gastric artery
describe the splenic artery
- Goes to the spleen
- Easily identifiable as it is very torturous – blood pressure in this region is high
- Course of the splenic artery goes through the stomach
what does the common hepatic do
gives a supply to the liver
what does the common hepatic split into
splits into the gastroduodenal
splits in the right gastric
describe what the gasproduodenal splits into
- Gastroduodenal gives supraduodenal and superior pancreaticoduodenal
- Gastroduodenal gives rise the right gastroepiploic this gives blood supply to the great curvature
what arises from the splenic artery
the left gastroepiploic comes from the splenic artery
what does the right gastric supply
- The right gastric is the 2nd branch from the common hepatic, supplies lesser curvature and anatomises with the right gastric
what is the continuation of the common hepatic
- Common hepatic carries on as the hepatic artery proper which goes to the liver
where do the gastric arteries lie
Gastric arteries in the lesser omentum
where do the gastroepiploic arteries lie
- Gastroepiploic arteries in the greater omentum
what does the superior mesenteric artery supply
• Supplies the distal duodenum (via inf pancreaticoduodenal a.), jejunum and the ileum (via jejunal & ileal arteries in the mesentery)
• Supplies the ascending and the transverse colon via the ileocolic, the right and the middle colic arteries
- supplies the midgut
how do you tell the difference between the jejunum and ileum
- As small intestine goes through the dimateter reduces inside
- Can identify the two structures based on the blood supply to them
- The jejunum has longer vasa recta than the ileum, jejunum has greater vascularity
- In the jejunum there is smaller arterial arcades, as you move down into the ileum they separate out
- These vessels are contained within the double layer of visceral peritoneum
what are the branches of the superior mesenteric artery
- Colic artery
- right colic
- ileocolic
- appendicular
- marginal arteries
- jejunal and ill branches - these collectively are called the intestinal arteries
describe what the branches of the superior mesenteric artery supply
- Frist main branch is the middle colic artery – this supplies the upper right regions of the large intestine
- The right colic – supplies to the ascending part of the large intestine
- The ileocolic – this supplies the ileal where the large intestine and the small intestine meet
- The appendix is supplied by the appendicular artery, it is suspended by the terminal part of the ileum
- The superior mesenteric arteries will have the marginal artery these go around the margins
- The jejunal and ileal branches – collectively these are called the intestinal arteries
what are the inferior mesenteric arteries
- Supplies left colic artery
- Superior rectal artery
- Sigmoid artery
- Marginal artery – watershed overlap between SMA and IMA
what is the blood supply to the liver
- 75% of blood flow to liver from the hepatic portal system (liver also receives 25% from proper hepatic artery)
what forms the hepatic portal system
- Splenic and superior mesenteric veins meet posterior to head of pancreas to form portal vein
- Inferior mesenteric veins drains to splenic
