Blood supply, lymphatics and nerve supply to GI tract. Flashcards
Artery branches and levels?
The superior mesenteric artery supplies the _____ part of the duodenum through to the _______ _______, _______ _______ and ___________ ________ heading to the splenic __________.
The inferior mesenteric artery supplies the splenic _________ all the way through to the _________.
2nd, small intestine, ascending colon and transverse colon, heading to the splenic flexure.
flexure, rectum and anus.
Celiac trunk coming off it with 3 main branches, the__________, ___________ with tortuous nature and _________which supplies the lesser curvature of the stomach.
Right gastric comes off the _____________artery which supplies the ________ of the _________.
The ___________ artery supplies the greater curvature (don’t need to know where it comes from). It also supplies the ________________.
The _____________ artery comes off the splenic artery and supplies the ______________ of the stomach.
He didn’t say much about the short gastric artery.
There are also lots of ___________ between the various vessels.
Celiac trunk coming off it with 3 main branches, the common hepatic artery, splenic artery with tortuous nature and left gastric which supplies the lesser curvature.
Right gastric comes off the common hepatic artery which supplies the right side of the lesser curvature.
The right gastroepiploic artery supplies the greater curvature (don’t need to know where it comes from). It also supplies the greater omentum.
The left gastroepiploic artery comes off the splenic artery and supplies the left side of the greater curvature.
There are also lots of anastomosis between the various vessels.
SMA is coming just inferior to the ________ and anterior to the ____________. A little bit of the ________ _________ of the pancreas sits underneath the SMA.
SMA is coming just inferior to the pancreas and anterior to the duodenum. A little bit of the uncinate process of the pancreas sits underneath the SMA.
_______ arteries to the jejunum, ______ arteries to the Iliac.
________ artery supply ascending, middle colic to supply the transverse and almost all the way to the splenic flexure.
The vasa recta are the ……
Jejunal arteries to the jejunum, Ileac arteries to the Iliac.
Ileocolic artery which is going to split up later.
Right colic: supply ascending, middle colic to supply the transverse and almost all the way to the splenic flexure.
The vasa recta are the straight lines going from the jaejunal and ileial vessels to the small intestine.
How does the vasa recta change in the different bits of the bowel?
Why is this clinically important?
Tells you if you have jejunum or ileum as this is the only thing to tell them apart.
You want to tie these vasa recta off if you are doing a surgery so that you don’t get bleeding.
Inferior mesenteric artery goes to the ______ and has an ______ and _________ branch.
__________ supplies the splenic flexure, the ___________ branch supplies __________.
There is also a ________ artery which supplies the sigmoid colon and a ___________ artery which supplies the rectum.
Inferior mesenteric artery: splits into the left colic artery.
There is then an ascending and descending branch of the colic artery.
Ascending supplies the splenic flexure, the descending branch supplies most of the descending part of the colon.
There is also a sigmoid artery which supplies the sigmoid colon and a superior rectal artery which supplies the rectum.
Why is the artery at the top important?
The marginal artery is very important.
It is an anastomotic vessel which shares blood between all of these vessels and even the sigmoid vessels also.
Portal system drains _______ _______ blood.
If you get portal hypertension because of _______ then the portal system becomes overloaded, there are 3 important _________ to the inferior vena cava. Where are they, their main drainage site and implications?
Portal system drains nutrient rich blood.
If you get portal hypertension because of cirrhosis then the portal system becomes overloaded, there are 3 important anastomoses to the inferior vena cava.
- The oesophageal varices: this is a serious condition. This is the junction between the left gastric vein and the tributaries to the azygous vein.
- Caput madusae: blood backflows through the para umbilical veins which then spread over the superficial abdominal wall.
- Anorectal varices: not haemorrhoids but look like them. Between inferior and superior rectal veins which drain into the portal system.
Explain the drainage of lymph?
Important for cancers.
Drains into epicolic vessels: adjacent to the colon.
To the paracolic which are the ones in yellow and in the mesenteric edge of colon
To intermediate lymphnodes (purple) then the prearotic which are around the aorta (the inferior and superior mesenteric artery).
Doing a colectomy it is important to get all of these.
Nerves and which spinal nerves they come from?
They contribute to the splanchnic nerves which control the blood supply in the viscera.
The greater splanchnic nerves are from the thoracic splanchnic nerves which comes out from T5 to T9.
There is the lesser which comes from T10 to T11 and least which is T12.
Pain fibres also travel through these nerves which is why you can sometimes get a referred pain.
Parasympathetic nerves which go via the hypogastric plexus. It is complicated he said.
What are the different plexus in the GI system?
Where do they sit?
