Gastro-Intestinal Tract Flashcards
What branches of the spinal cord of the peripheral nervous system supply the abdominal organs?
T13
L1-3
What does the dorsal and ventral branch of the peripheral nervous system supply?
Dorsal- dorsal abdominal skin
Ventral- splits medial, lateral and lateral cutaneous
What do the three parts of the ventral branch of the peripheral nervous system supply?
Medial- runs between transverse abdominus and internal abdominal oblique- supplies TA, IAO, RA and ventral abdominal skin
Lateral- perforates internal abdominal oblique and runs between IAO and external abdominal oblique- supply IAO and EAO
Lateral cutaneous- perforates external abdominal oblique supplying lateral skin
What are the differences between the sympathetic nervous system and parasympathetic nervous system?
Sympathetic fight or flight, suspend digestion, ganglia as site of synapses, long post ganglionic
Parasympathetic- homeostasis, promote digestion, plexus- no synapses until reach organ of innervation, short post ganglionic
What two types of nerves from the sympathetic nervous system supply the GI?
Major/minor splanchnic nerves
Lumbar splanchnic nerves
Where do the major and minor splanchnic nerves synapse and where do the lumbar splanchnic nerves synapse?
Major/minor- caeliaco-mesenteric ganglia
Lumbar- caudal mesenteric ganglion
What two nerves parasympathetically supply the GI?
Vagus and Pelvic
How does the vagus supply the abdominal organs?
Splits as it enters abdomen and reunites to form:
Dorsal vagal trunk- visceral surface of stomach/ pylorus
Ventral vagal trunk- parietal surface of stomach/ pylorus and liver
Continues to calico-mesenteric plexus and follows arteries to rest of organs
Where does the pelvic nerve emerge from the spinal cord and where does it pass through before the organs?
S1-S3
Passes through pelvic plexus then follows arteries to pelvic organs
What arteries supply the abdominal wall?
Cranial abdominal
Deep external iliac
Cranial epigastric
Caudal epigastric
What do each of the abdominal wall arteries supply?
Cranial abdominal- cranio-dorso-lateral
Deep external iliac- caudo-dorsal-lateral
Cranial epigastric- cranio-ventero-lateral
Caudal epigastric- caudo-ventero-lateral
What are the three major branches off the aorta which supply the abdominal organs?
Caeliac- cranial abdominal organs
Cranial mesenteric- mid-abdominal
Caudal mesenteric- caudal abdominal organs
What are the three branches of the caeliac artery?
Hepatic
Left gastric
Splenic
What are the three branches of the hepatic artery?
Hepatic branches
Right gastric
Gastroduodenal
What does each of the three hepatic artery branches supply?
Hepatic branches- liver, cystic artery to gall bladder
Right gastric- right lesser curvature of stomach
Gastroduodenal- right gastro-epiploic artery to right greater curvature of stomach, cranial pancreatico-duodenal artery (cranial lobe of pancreas/duodenum)
What does the left gastric artery supply?
Left lesser curvature of the stomach
Oesophageal branches to oesophagus
What does the splenic artery supply?
Short gastric arteries- greater curvature of stomach
Pancreatic branches- left lobe of pancreas
Left gastro-epiploic- left greater curvature of stomach
What are the three branches of the cranial mesenteric artery?
Ileo-colic artery
Caudal pancreatico-duodenal artery
Jejunal arteries
What do the caudal pancreatico-duodenal artery and jejunal arteries supply
Pancreatico-duodenal artery- caudal right lobe of pancreas and duodenum
Jejunal arteries- jejunum
What are the 5 branches of the ileo-colic artery and what do they supply?
Middle colic artery- transverse colon Right colic artery- right colic flexure Colic branch of ileo-colic- ascending colon Caecal branch of ileo-colic- caecum Mesenteric ileal- ileum
What are the two branches of the caudal mesenteric arteries and what to they supply?
Left colic artery- left colic flexure/descending colon
Cranial rectal artery- cranial rectum
What other abdominal organs are there that don’t supply GI organs?
Left and right renal arteries
Left and right ovarian/testicular arteries
What is an anastomoses?
Safety mechanism for if an artery gets occluded the organ will continue to receive blood
Where are anatomises present in the GI artery tract?
Left/right gastric Left/right gastro-epipoloic Cranial/caudal pancreatico-duodenal Middle/right colic Middle/left colic Colic branch of ileo-colic/right colic Mesenteric ileal/jejunal jejunal/jejunal
