The document discusses the blood supply of the gut. It is divided into three parts: the foregut, midgut, and hindgut. The foregut receives its blood supply from the celiac trunk. The midgut is supplied by the superior mesenteric artery. The hindgut receives its blood supply from the inferior mesenteric artery. It then describes the branches and blood supply areas of each of these arteries in detail. It also discusses the portal vein and its tributaries, which drain the venous blood from the structures supplied by these arteries.

1. Blood supply of the gut
Dr. Mohamed Elfiky
Professor of anatomy and embryology

2. The Gut
The foregut begins with the abdominal esophagus and ends just inferior to
the major duodenal papilla, midway along the descending part of the
duodenum. It includes the abdominal esophagus, stomach, duodenum
(superior to the major papilla), liver, pancreas, and gallbladder. The spleen
also develops in relation to the foregut region. The foregut is supplied by
the celiac trunk.
The midgut begins just inferior to the major duodenal papilla, in the
descending part of the duodenum, and ends at the junction between the
proximal two-thirds and distal one-third of the transverse colon. It includes
the duodenum (inferior to the major duodenal papilla), jejunum, ileum,
cecum, appendix, ascending colon, and right two-thirds of the transverse
colon. The midgut is supplied by the superior mesenteric artery
The hindgut begins just before the left colic flexure (the junction between
the proximal two-thirds and distal one-third of the transverse colon) and
ends midway through the anal canal. It includes the left one-third of the
transverse colon, descending colon, sigmoid colon, rectum, and upper part
of the anal canal. The hindgut is supplied by the inferior mesenteric artery
Mohamed el fiky

3. Celiac trunk
The celiac trunk is the anterior branch of the
abdominal aorta supplying the foregut. It arises
from the abdominal aorta immediately below the
aortic hiatus of the diaphragm (, anterior to the
upper part of vertebra LI. It immediately divides
into the left gastric, splenic, and common hepatic
arteries.
Mohamed el fiky

4. Celiac trunk
Relations :
A - on each side :
1- Coeliac ganglion and coeliac plexus of autonomic nerves
which surrounds it & sends 2ry plexus around its branches .
2- A crus of the diaphragm.
3- Coeliac group of lymph nodes
B- Anteriorly: Cavity of the lesser sac separating it from the
lesser omentum.
C- Superiorly : Median arcuate ligament of the diaphragm.
D- Inferiorly : Upper border of pancreas .
Mohamed el fiky

5. A- Left gastric artery
Branches of Celiac trunk
It is the smallest branch.
Course : It passes upwards and to the left (behind the lesser sac ) till
it reaches the lower end of the oesophagus, then it descends
downwards along the lesser curvature of the stomach (between the 2
layers of the lesser omentum ) to end by anastomosing with the right
gastric artery about the middle of the lesser curvature.
Branches :
1- Oesophageal branches : to the lower end of the oesophagus. 2-
Gastric branches : to both surfaces of the stomach.
Mohamed el fiky

6. B- Splenic artery
Branches of Celiac trunk
It is the largest branch of the coeliac trunk and is a tortuous artery .
Course and Relations :
- It passes to the left side above the upper border of the pancreas and
infront of the left kidney where it enters the lieno-renal ligament to
reach the hilum of spleen where it ends by giving 5-6 terminal branches .
- Along its course it lies behind the stomach but separated from it by the
cavity of the lesser sac .
Branches of splenic artery :
1- Pancreatic branches : to the body and tail of the pancreas .
2- Short gastric arteries : 5-7 small branches to the fundus of the
stomach through the gastro-splenic ligament.
3- Left gastro-epiploic artery : runs on greater curvature of the stomach .
4- Terminal splenic branches : 5-6 terminal branches which enter the
hilum of the spleen (end arteries ) Mohamed el fiky

7. C- hepatic artery
Branches of Celiac trunk
It is intermediate in size between the splenic and left gastric arteries .
- Course and relations :
- It passes forwards and to the right to reach the upper border of the 1st
part of duodenum .
- Then, it curves upwards and ascends in the free border of lesser
omentum (in front of the epiploic foramen) to reach the porta hepatis
The portal vein lies behind it while common bile duct lies to its the right
side.
- It ends in the porta hepatis by dividing into right and left terminal
hepatic branches.
Mohamed el fiky

8. Branches of hepatic artery :
1- Gastro-duodenal artery :
Descends behind the 1st part of the duodenum (in front of
portal vein and medial to common bile duct.
Ends by dividing into : right gastro-epiploic and superior
pancreatico- duodenal artery .
2- Right gastric artery : Passes to the left along the lesser
curvature of the stomach . Ends by anastomosing with the left
gastric artery .
3- Supra-duodenal artery :
- Inconstant small artery (may be absent) which supplies the
upper part of the first part of duodenum .
4- Right terminal hepatic branch : enters the right lobe of the
liver.
5- Left terminal hepatic branch : enters the left lobe of the
liver.
6- Cystic artery : passes behind the common hepatic and cystic
ducts to reach the gall bladder . It usually arises from the right
terminal branch .
C- hepatic artery
Mohamed el fiky

9. Superior Mesenteric Artery
Origin : from the front of abdominal aorta opposite the lower border of L1 vertebra ( 1 cm .
below the origin of the coeliac trunk )
Course and Relations :
¨ At its origin it lies behind the body of pancreas where the splenic vein lies above it and the
left renal vein lies below it
¨ Then, it appears at the lower border of the pancreas and runs downwards and to the right
through root of mesentery ( with a curve concave to the right The superior mesenteric vein
lies along the right of the artery and both crosses the following structures in succession :
1- Left renal vein.
2- Uncinate process of pancreas.
3- 3rd part of the duodenum.
4- Abdominal aorta.
5- Inferior vena cava.
6- Right genitor-femoral nerve.
Termination : in the right iliac fossa by anastomosing with the ileal branches of the ileocolic
aretry . Mohamed el fiky

10. Branches of superior mesenteric artery
1- Inferior pancreatico-duodenal artery:
¨ Arises from the superior mesenteric artery as it crosses the uncinate process
of pancreas .
¨ Ascends between the head of pancreas and the duodenum .
¨ Ends by anastomosing with the superior pancreatico-duodenal artery
2- Jejunal and ileal branches :
12- 15 branches which arise from the left convex side of the artery . They
pass through the mesentery dividing into branches which anastomose with
each other forming a series of arterial arches , the terminal ones give straight
end arteries ( vasa recta ) which supply
the jejunum and ileum .
3- Ileo-colic artery:
It runs downwards and to the right on posterior abdominal wall giving the
following branches :
1- Ileal branches : to the terminal part of the ileum
2- Anterior caecal branch to the front of caecum
3- Posterior caecal branch to the back of the caecum
4- Appendicular branch passes behind the terminal part of the ileum and reaches the appendix through its mesentery
(meso-appendix).
5- Ascending branch to lower 1/3 of ascending colon anastomosing with the descending branch of right colic artery .
Mohamed el fiky

11. 4- Right colic artery : Arise from the right side of the superior mesenteric
artery a little below middle colic artery
Runs to the right crossing the Rt. psoas major, Rt. ureter and Rt. gonadal
vessels.
Near the ascending colon it divides into 2 branches : ascending and
descending which supply the upper 2/3 of ascending colon and
anastomose with ascending branch of ileo-colic artery and right branch of
middle colic artery .
5- Middle colic artery :
Arises from the superior mesenteric artery just below the pancreas
It enters the transverse mesocolon where it divides into:
1- Right branch anastomosing with ascending branch of right colic artery.
2- Left branch anastomosing with ascending branch of left colic artery.
Both branches of the middle colic artery supplies the right 2/3 of
transverse colon.
Branches of superior mesenteric artery
Mohamed el fiky

12. Inferior Mesenteric Artery
Origin : from the front of abdominal aorta at the level of 3rd lumbar
vertebra behind the 3rd part of the duodenum and 1.5 inches above the
bifurcation of aorta .
Course and Relations :
1- At the beginning, it lies behind 3rd part of the duodenum which
separates it from the superior mesenteric artery .
2- Then, it descends downwards and to the left behind the peritoneum of
posterior abdominal wall lying in front of :
a.Abdominal aorta.
b. Left sympathetic chain. c. Left psoas major muscle.
3- Inferior mesenteric vein and the left ureter lie to the left side of the
lower part of the artery.
4- Inferior mesenteric artery enters the pelvis by crossing the middle of
the left common iliac artery, and becomes superior rectal artery . Mohamed el fiky

13. Branches : (to the left 1/3 of transverse colon , descending colon , sigmoid colon and rectum ).
Branches of inferior mesenteric artery
1- Left colic artery: runs to the left behind the peritoneum of the posterior
abdominal wall crossing in front of left psoas major, left ureter and left gonadal
vessels.
2- Sigmoid arteries : 2-3 arteries : Pass downwards and to the left behind the
peritoneum of post.
abdominal wall crossing in front of Lt. psoas major, Lt. ureter and Lt.
gonadal vessels. The upper one anastomoses with the descending branch of the left
colic artery. The lower one anastomoses with the superior rectal artery. The sigmoid
arteries supply the lower part of the descending colon , and sigmoid colon .
3- Superior rectal artery :
§ It is the continuation of the inferior mesenteric artery .
It enters the pelvis at the middle of left common iliac artery .
§ It passes through the medial limb of sigmoid mesocolon then along the posterior
surface of the rectum supplying it and upper 1/2 of anal canal
Mohamed el fiky

14. Blood Supply of the
Ascending Colon
Mohamed el fiky

15. VENOUS DRAINAGE OF GUT
Portal Circulation
The veins which drain the stomach , small intestine , most of large intestine, spleen, pancreas and gall bladder end in
the portal vein .
Portal Vein
Origin:
Formed behind the neck of pancreas by union of 2 veins:
a. Splenic vein.
b. Superior mesenteric vein.
Termination:
In the porta hepatis by dividing into 2 branches: right and left.
Length: 2-3 inches.
Mohamed el fiky

16. Course and Relations: It has 2 parts:
1- Retro-duodenal part : Ascends upwards and to the right behind the
1st part
of the duodenum lying:
¨ In front of the I.V.C.
¨ Behind gastro-duodenal artery and common bile duct.
Supra doudenal part :
Ascends in the free margin of lesser omentum having the following
relations:
a. Epiploic foramen: posterior to it.
b. Common bile duct: anterior and to right. c. Hepatic artery: anterior
and to the left.
On reaching the porta hepatic, it divides into 2 terminal branches: a.
Right to right lobe of the liver.
b. Left to left lobe of the liver
2 ligaments attached to left terminal branch of portal vein
1- Ligamentum teres (represents the obliterated umbilical vein of the
embryo). 2- Ligamentum venosum (represents the obliterated ductus
venosus of the
Portal Vein
Mohamed el fiky

17. Tributaries of portal vein
a. 2 main tributaries
1. Splenic vein.
2. Superior mesenteric vein .
b. 2 veins from the stomach:
1. Right gastric v.
2. Left gastric v.
c. 2 veins drain into its terminal branches :
1- Cystic veins (from gall bladder) drain into right terminal branch.
2- Para-umbilical veins (from anterior abdominal wall), run with ligamentum teres and
end into its terminal branch.
Mohamed el fiky

18. Splenic Vein
Begins: by the union of 5-6 splenic veins at the hilum of the spleen.
Course and Relations :
- The vein passes to the right through the lino-renal ligament, then
across the posterior abdominal wall behind the body of pancreas
and infront of left kidney and abdominal aorta ( below the splenic
artery ).
Ends: behind the neck of pancreas by uniting with the superior
mesenteric vein to form the potal vein.
Tributaries :
1- Receives tributaries corresponding to branches of splenic artery
(mention them).
2- Inferior mesenteric vein which is a continuation of the superior
rectal vein and recieves tributaries corrosponding to branches of
inferior mesenteric artery. Mohamed el fiky

19. Superior mesenteric vein
Begins : at the lower end of root of mesentery .
Course and relations : runs upwards and to the left along
right side of the
superior mesenteric artery ( having the same relations )
Ends : Behind the neck of pancreas by joining the splenic
vein to form portal
vein.
Tributaries : Correspond to branches of superior
mesenteric artery (mention
them + the right gastro-epiploic vein).
Mohamed el fiky

20. Connections between the portal and systemic veins
(Porto-systemic Anastomosis)
1- At the lower end of the oesophagus :
- Oesophageal branches of left gastric vein (portal) with oesophageal branches of azygos vein (systemic)
- In portal hypertension, it leads to oesophageal varices .
2- At the anal canal :
- between superior rectal (portal) and middle and inferior rectal (systemic)
- In portal hypertension, it leads to internal piles.
3- Around the umbilicus :
- Between para-umbilical veins (portal) with superficial veins of the anterior abdominal wall (systemic).
-In portal hypertension, it leads to dilated, radiating veins around the umbilicus
called (caput medusae)
4- Extra-peritoneal : Between right and left colic veins (portal)
and right and left renal veins (systemic)
5- In the bare area of the liver :
- Between twigs from veins of the liver (portal) and phrenic veins (systemic).
6- Inside the liver itself.
7- The vein of Ritzius : Connects the superior mesentric vein (portal ) with the
inferior vena cava (systemic ).
Mohamed el fiky

21. (Porto-systemic Anastomosis)
Mohamed el fiky