Lecture 25: Blood and Nerve Supply of GIT

- Abdominal Aorta: continuation of thoracic aorta, gives off 3 unpaired branches to the GIT - Celiac trunk: spplies tomach to major duodenal papilla - Superior mesenteric: supplies duodenum at the major duodenal pailla to proximal 2/3 of transverse colon - Inferior mesenteric: supplies 1/3 or transverse colon to the rectum.

- Left gastric artery: stomach and esophogas - Common Heaptic a.: supplies liver, stomach, duodenum, pancrease 1. Heptice a. Proper: 2. Gastroduodenal a: may be eroded by posterior perforation of a duodenal ulcer. - Splenic a: may be eroded by post. perforation of a gastric ulcer; supplies stomack pancreas and spleen.

- Righ gastric a: lesser curvature - Right hepatic a: right lobe of liver and gall bladder (via cystic a. in triangle of calot- common hepatic duct, cystic duct, and liver) -Left hepatic a: left lobe of liver

- Supraduodenal a: duodenum - Sup. pancreatic duodenal a: and and post branches supply the head of the pancreas and ucinate process and duodenum: anastomose with ant. and post branches of inferior pancreaticoduodenal ateries - Right gastroespiploic a: supplies greater curvature of stomach

- Pancreatic a: body/tail of pancreas - Short gastric a: fundus of stomach - Left gastroepiploic a: greater curvature

- Inferior pancreaticoduodenal a: head and uncinate process of pancreas: duodenum - Intestinal (jejunal/ileal) a - Ileocolic a: appendix, cecum, ascendic colon - Right colic a: ascending artery - Middle colic a: transverse colon

A. Gasrtoduodenal a 1. Supraduodenal a. 2. Ant. sup. PD a 3. Post sup. Pd a B. superior Mesentaric A: 1. ant. inf PD a 2. Post inf PD a

- Left colic a. : descending colon - Sigmoid atery: sigmoid colon - sperior rectal a: rectum direct continuation of inf mesentaric a.

- Anastomoses among terminal branches of the superior adn inferior mesenteric arteries. - Forms a continuouos "marginal" artery around the ascending, transverse, descending and sigmoid colons.

- Drains blood from GIT, spleen,a nd pancreas inot the liver. - Supplies 75% of blood in to the liver. - Forms by union of superior mesenteric and splenic v, posterior to the head of the pancreas. - Inferior mesenteric v may drain into splenic or poral vein, paraumbilical v drains into the portal vein,

- Left gastric v: azygos v - Superior rectal v: middle rectal v and inferior rectal v - Paraumbilical v: superfical v of ant abdominal wall - Retroperitoneal v: lumbar v - Veins in bare area of the liver: veins of the diaphragm and internal thoracic v.

1. hematemesis 2. Caput medusa 3. hematochezia 4. splenomegaly

- Fresh bleeding from esophageal varices (enlarged esophageal v drain inot the azygos veins due to the higher pressure in the left gastric v)

- enlarged parambilica v which drain directly into the portal vein dump oportal blood into the superficial veins of the anterior abdominal wall, specifically the superficail epigastric veins.

Fresh bleeding from hemorrhoids (enlarged inferior and middle rectal v, which anastomose with the superior rectal v, a direct continuationof the inf mesenteric v.