Blood and Nerve Supply of the GIT Flashcards
Which organs make up the foregut?
Distal part of oesophagus
Stomach
Duodenum before the major duodenal papilla
Superior portion of pancreas
Spleen
Gallbladder
Liver
Which organs make up the hindgut?
Duodenum after the major duodenal papilla
Inferior portion of pancreas
Jejunum
Ileum
Caecum
Appendix
Ascending colon
Proximal 2/3 of transverse colon
Which organs make up the foregut?
Distal 1/3 of the transverse colon
Descending colon
Sigmoid colon
Rectum
Upper part of the anal canal
What is the blood supply of foregut?
Coeliac trunk
What is the blood supply of the midgut?
Superior mesenteric artery
What is the blood supply of the hindgut?
Inferior mesenteric artery
At which vertebral level does the coeliac trunk arise?
T12
What are the main branches of the coeliac trunk?
Left gastric artery
Splenic artery
Common hepatic artery
What is the course of the splenic artery to reach the hilum of the spleen after arising from the splenic hilum?
It runs in the stomach bed, along the superior aspect of the tail of the pancreas to pass to the splenorenal ligament to enter the hilum of the spleen
What are the branches of the splenic artery?
Short gastric arteries
Left gastroepiploic (gastro-omental) artery
Pancreatic branches
What are the branches of the common hepatic artery?
Hepatic artery proper
Gastroduodenal artery
What are the branches of the hepatic artery proper?
Right and left branches to the liver
Right gastric artery
What are the branches of the gastroduodenal artery?
Supraduodenal artery
Anterior superior pancreaticoduodenal artery
Posterior superior pancreaticoduodenal artery
Which arteries supply to stomach?
Left and right gastric arteries
Left and right gastroepiploic/-omental arteries
Short gastric artery
What is the origin of the left gastric artery?
Coeliac trunk
What is the course of the left gastric artery?
After arising, it runs in the lesser omentum to pass to the cardia of the stomach to course along the lesser curvature of the stomach
What does the left gastric artery supply?
Left part of lesser curvature of the stomach
Distal end of oesophagus through oesophageal arteries
What does the left gastric artery anastomose with?
Right gastric artery
Where does the right gastric artery originate from?
Hepatic artery proper
What is the course of the right gastric artery?
It courses along to the left on the lesser curvature of the stomach
What does the right gastric artery supply?
Right portion of lesser curvature of the stomach
What does the right gastric artery anastomose with?
Left gastric artery
Where does the right gastroepiploic/-omental artery arise from?
Gastroduodenal artery
What is the course of the right gastroepiploic/-omental artery?
It runs to the left along the greater curvature of the stomach
What does the right gastroepiploic/-omental artery supply?
Right portion of the greater curvature of the stomach
What does the right gastroepiploic/-omental artery anastomose with?
Left gastroepiploic/-omental artery
Where does the left gastroepiploic/-omental artery arise from?
Splenic artery
What is the course of the left gastroepiploic/-omental artery?
It courses to the right along the greater curvature of the stomach
What does the left gastroepiploic/-omental artery supply?
Left portion of the greater curvature of the stomach
What does the left gastroepiploic/-omental artery anastomose with?
Right gastroepiploic/-omental artery
Where does the short gastric artery arise from?
Splenic artery at its distal end
What is the course of the short gastric artery?
It passes between the layers of the gastrosplenic ligament to the fundus of the stomach
What does the short gastric artery supply?
Fundus of the stomach
Which arteries supply the dudoenum?
Branches of the coeliac trunk proximal to the entry of the major duodenal papilla
Branches of the SMA distal to the entry of the major duodenal papilla
Which branches of the coeliac trunk supply the duodenum?
Anterior superior and posterior superior pancreaticoduodenal artery
Supraduodenal artery
Which branches of the superior mesenteric artery supply the duodenum?
Anterior inferior and posterior inferior pancreaticoduodenal artery
Where do the pancreaticoduodenal arteries lie?
They lie in the curve between the duodenum and the head of the pancreas?
Where does the superior pancreaticoduodenal artery arise from?
Gastroduodenal artery
Which part of the duodenum is supplied by the superior pancreaticoduodenal artery?
Duodenum proximal to the entry of the bile duct into its second part
Where does the supraduodenal artery arise from?
Gastroduodenal artery
Which part of the duodenum does the inferior pancreaticoduodenal artery arise from?
The duodenum distal to the entry of the bile duct into its second part
Which arteries supply the pancreas?
Superior and inferior pancreaticoduodenal arteries
Pancreatic branches of splenic artery
What supplies the body and tail of the pancreas?
Small pancreatic arteries arising from the splenic artery
What is the largest of the pancreatic branches arising from the splenic artery?
Greater pancreatic artery or pancreatic magma artery
What is the most distal pancreatic branch arising from the splenic artery?
Dorsal pancreatic artery
Which arteries supply the head of the pancreas?
Anterior and posterior superior pancreaticoduodenal arteries
Anterior and posterior inferior pancreaticoduodenal arteries
Where does the liver receive its blood supply from?
Hepatic artery proper
Portal vein
Where does the common hepatic artery divide into the gastroduodenal artery and hepatic artery proper?
Superior part of the duodenum at the omental foramen
What is the relations of the hepatic artery proper in relation to the structures in the portal triad?
It is anterior to the portal vein
It lies left to the bile duct
What forms the portal vein?
The union of the splenic vein and superior mesenteric vein
How does the inferior mesenteric vein join the portal system?
It can drain into the splenic vein
It can drain into the SMV
It can drain into the junction between the splenic vein and SMV
Which artery supplies the gallbladder and cystic duct?
Cystic artery
Where does the cystic artery arise from?
Right hepatic artery
At what vertebral level does the superior mesenteric artery arise?
L1
What does the SMA pass anterior to after arising?
Uncinate process of pancreas
3rd part of duodenum
Left renal vein
What does the SMA pass within?
The root of the mesentery
What are the branches of the superior mesenteric artery?
Inferior pancreaticoduodenal artery
Intestinal artery - jejunal and ileal
Ileocaecal artery
Right colic artery
Middle colic artery
Which artery supplied the jejunum?
Jejunal artery
Which artery supplies the ileum?
Ileal artery
What are the intestinal arteries arranged in as they pass through the layers of the mesentery?
Anastomotic/Arterial arcades
What do the arterial arcades form?
They form smaller, straight arteries known as the vasa recta
How does the arterial arcades and vasa recta differ between the jejunal and ileal arteries?
Jejunum = smaller number of arterial arcades but longer vasa recta
Ileum = large number of arterial arcades but shorter vasa recta
Which artery supplies the caecum?
Ileocaecal artery
Which artery supplies the appendix?
Appendicular artery
Where does the appendicular artery arise from?
Ileocaecal artery
Which artery supplies the ascending colon?
Right colic artery
Which artery supplies the proximal 2/3 of the transverse colon?
Middle colic artery
What are the branches of the inferior mesenteric artery?
It gives of the left colic artery and sigmoid arteries
It then continues as the superior rectal artery
At which vertebral level does the inferior mesenteric arise from?
L3
Which artery supplies the descending colon?
Left colic artery
Which artery supplies the distal 1/3 of the transverse colon?
Marginal branch of left colic artery
Which artery supplies the sigmoid colon?
Sigmoid arteries
Which artery supplies the superior 1/3 of the rectum and superior anal canal?
Superior rectal artery
What does parasympathetic innervation of the GIT stimulate?
Peristalsis
Sphincter relaxation
Secretomotor to glands
What does sympathetic innervation to the GIT provide?
Slows/inhibits peristalsis, urination and defaecation
Vasoconstriction
Pain sensation
What provides sympathetic nervous supply to the GIT?
Thoracolumbar segment of spinal cord (T1-L2/3)
Thoracic splanchnic nerves
Lumbar splanchnic nerve
Hypogastric nerve
Which nerves provide parasympathetic innervation to the GIT?
Craniosacral
Vagus nerve
Pelvic splanchnic nerves
What is the 2 neuronal pathway of the sympathetic nerves?
A neuronal pathway that begins in the spinal cord with a preganglionic nerve that synapses with a postganglionic nerve outside the spinal cord
Where does the preganglionics of the sympathetic NS begin?
They begin in the lateral horn of grey matter in the spinal cord in the thoracolumbar segment (T1-L2/3)
What is the paravertebral ganglia?
These are ganglia situated on either side of the vertebral column, beginning at the base of the skull and ending inferiorly at the coccyx as the ganglion impar, which contain postganglionic cell bodies
What does the paravertebral ganglia make up?
Sympathetic chain
How do the sympathetic preganglionics leave the spinal cord?
Via the ventral horn
What are the different synapsing pathways that sympathetic preganglionics have once inside the paraverterbal ganglia?
It can synapse with the ganglia at that level
It can ascend to synapse with a postganglionic nerve at a higher level
It can descend to synapse with a postganglionic nerve at a lower level, forming splanchnic nerves
What are the root values of the greater thoracic splanchnic nerve?
T5-T9
What is the root value for the lesser thoracic splanchnic nerve?
T10-T11
What is the root value for the least thoracic splanchnic nerve?
T12
Where to the preganglionic thoracic splanchnic nerves synapse with the postganglionic nerve?
At the prevertebral ganglia situated around the branches of the aorta
What are prevertebral ganglia?
These are ganglia situated around the abdominal aorta and its branches
What are the prevertebral ganglia?
Coeliac ganglion
Superior mesenteric ganglion
Inferior mesenteric ganglion
Which ganglia/plexus supplies the foregut structures?
Coeliac ganglion/plexus
Which nerves contribute sympathetic innervation to the coeliac plexus?
Greater splanchnic nerve
Which nerve contributes parasympathetic innervation to the coeliac plexus?
CN X
