Anatomy of the GI Part 1 Flashcards
What are the boundaries of the abdominal cavity?
Superiorly - diaphragm
Inferiorly - pelvic floor muscles
Anteriorly - abdominal wall muscles
Posteriorly - lumbar vertebral column
What is an omenta?
A double fold passing from the stomach and duodenum to other organs or the body wall
What does the peritoneal cavity contain?
Peritoneal fluid
What are the two sacs of the peritoneum?
The greater and lesser sacs
What connects the greater and lesser sacs?
The epiploic foramen/foramen of Winslow
What are the constrictions of the oesophagus?
Cervical - Pharyngo-oesophageal (15cm from incisors)
Thoracic - Broncho-aortic (22.5&27.5 cm from incisors)
Diaphramatic - where it passes through the oesophageal hiatus (40cm from incisors)
What is the function of the pyloric sphincter?
To control discharge of stomach contents into the duodenum
What 3 structures make up the portal triad?
Hepatic Artery, Portal Vein and Bile Duct
What is the surface anatomy of the liver?
The liver lies deep to ribs 7-11 on the right side
Where is bile produced?
The liver
Where is bile stored and concentrated?
The gallbladder
Where does the pancreas lie?
Along the transpyloric plane (L1/L2)
What are the branches of the coeliac trunk?
Left gastric artery, hepatic artery and splenic artery
What is the origin of the superior mesenteric artery?
The abdominal aorta at L1
What are the main branches of the superior mesenteric artery?
Jejunal and Ileal arteries
What is the origin of the inferior mesenteric artery?
Anterior branch of the abdominal aorta at L3
What are the branches of the inferior mesenteric artery?
Left colic, sigmoid arteries and superior rectal artery
What is the parasympathetic innervation of the abdominal organs?
Vagus nerve and pelvic splanchnic nerves (S2, S3 & S4)
What is the sympathetic innervation of the abdominal organs?
Abdominopelvic splancnic nerves:
- Greater (T5-9)
- Lesser (T10-11)
- Least (T12)
Prevertebral sympathetic ganglia and abdominal aortic plexus
What is the function of the portal vein?
It collects poorly oxygenated but nutrient rich blood from the abdominal part of the GI tract (including the spleen and pancreas) and carries it to the liver
What veins form the portal vein?
Splenic vein and superior mesenteric veins
What is the location of the portal vein?
Behind the neck of the pancreas (L2)
What are the sites of porto-systemic anastomoses?
Anorectal, gastrooesophageal junctions and umbilicus
What are the four quadrants of the abdomen?
Left Upper/Lower and Right Upper/Lower
What lines divide the abdomen into the four quadrants?
Transumbilical and median line
What are the lines that divide the abdomen into 9 regions?
Right/Left midclavicular, transpyloric and transtubercular
What organs and structures are found in the right hypochondrium?
Liver, gallbladder, R. kidney and small intestine
What organs and structures are found in the epigastric?
Stomach, liver, pancreas, duodenum, spleen and adrenal gland
What organs and structures are found in the left hypochondriac?
Spleen, colon, L. kidney and pancreas
What organs and structures are found in the right lumbar region?
Gall bladder, liver and ascending colon
What organs and structures are found in the umbilical region?
Umbilicus, jejunum. ileum, duodenum, IVC and abdominal aorta
What organs and structures are found in the left lumbar region?
Descending colon and left kidney