Upper GIT Flashcards
What is the GI tract?
A continuous tube which stretches from mouth to anus
What is the function of the GIT?
Provide the body with continual supply of water, electrolyte, vitamins and nutrients
What is the peritoneum?
A serous membrane which lines the abdominopelvic cavity and invests viscera
What are the 2 layers of the peritoneum?
- Parietal peritoneum
2. Visceral peritoneum
Where does the parietal peritoneum line?
Internal surface of the abdominopelvic wall
Where does the visceral peritoneum line?
Viscera such as stomach and intestines
What are retroperitoneal structures?
Structures within abdominal cavity which are not suspended by a mesentery
Where are retroperitoneal structures located?
Between the peritoneum and the posterior abdominal wall
Name 10 retroperitoneal structures
- Supra-renal gland
- Aorta
- Duodenum
- Pancreas
- Ureters
- Inferior vena cava
- Kidneys
- Oesophagus
- Rectum
- Ascending and descending colon
What is a mesentery?
A double layer of peritoneum which suspends some abdominal organs
What do mesenteries connect?
Intra-peritoneal organ to the posterior abdominal wall
How is a mesentery or omenta formed?
When two layers of peritoneum fuse
What are the 2 sacs of the peritoneal cavity?
- Greater sac
2. Lesser sac
Why is the lesser sac necessary?
Compensates for stretch of stomach following consumption of food
What is an omentum?
A double layer of peritoneum which joins two viscera
Name 2 omenta
- Great omenta
2. Lesser omenta
What is the greater omentum?
Four layered peritoneal fold which hangs like an apron from greater curvature of stomach
Where is the greater omentum attached?
Greater curvature of stomach and transverse colon
What is the lesser omentum?
A double layered peritoneal fold which connects lesser curvature of the stomach and proximal part of duodenum to the liver
What is the dividing line between the greater and lesser sac?
Transverse mesocolon
What is the oesophagus?
A muscular tube which joins the pharynx from vertebral level C6 to stomach ending at vertebral level T11
What 2 sphincters are found in the oesophagus?
- Cricopharyngeus muscle
2. Cardiac sphincter
What is the function of the oesophagus?
Propel food through neck and thorax to abdomen
Where does the stomach occupy?
Upper left quadrant
What are the 4 parts of the stomach?
- Cardiac portion
- Fundus
- Body
- Pylorus
What is the cardiac portion of the stomach?
Surrounds the entrance to the stomach and contains cardiac sphincter
What is the fundus of the stomach?
Area to the left of the cardiac orifice of the stomach which bulges upwards
What Is the body of the stomach?
Lies between the fundus and pylorus
What is the pylorus of the stomach?
Funnel shaped outflow region of the stomach
What are the two areas of the pylorus?
- Pyloric antrum - Wider
2. Pyloric canal - Narrower
How is the mucosa of the inner surface of stomach arranged?
Longitudinal folds called rugae
What is the function of rugae?
Allow stomach to increase SA enhancing the action of gastric secretions
What is the arterial supply to the apical surface of the stomach?
Short gastric arteries
What is the arterial supply to the less curvature of the stomach?
Right and left gastric
What is the arterial supply to the greater curvature of the stomach?
Right and left gastroepiploic
Where does the arterial blood supply to the stomach arise?
Celiac trunk
What 3 branches does the celiac trunk give?
- Splenic artery
- Left gastric artery
- Hepatic artery
How are the veins of the stomach named?
Parallel the name and courses of the arteries
What are the 4 parts of the duodenum?
- Superior
- Descending
- Horizontal
- Ascending
What is the duodenum?
First section of the small intestine
What shape is the duodenum?
C-shaped
What is the level of the superior portion of the duodenum?
L1
Between what vertebral levels does the descending duodenum run?
L1 - L3
What is the significance of the descending duodenum?
Common bile duct and pancreatic duct empty secretions here through ampulla of Vater
What is the level of the horizontal portion of the duodenum?
L3
Between what vertebral levels does the ascending duodenum run?
L3 - L2
What 2 arteries supply the duodenum?
- Superior pancreaticoduodenal from gastroduodenal artery
2. Inferior pancreaticoduodenal artery from superior mesenteric artery
What is the pancreas?
Digestive gland
Where does the pancreas lie?
Overlies transversely across bodies of L1 and L2 vertebrae, posterior to stomach between duodenum on right and spleen on left
What are the 5 main parts of the pancreas?
- Head
- Uncinate process
- Neck
- Body
- Tail
What is the significance of the head of the pancreas?
Sits within C-shaped duodenum and lies directly in front of inferior vena cava, aorta and right renal vessels
What is the significance of the neck of the pancreas?
On posterior surface superior mesenteric vein and splenic vein unite to form portal vein
What is the significance of the tail of the pancreas?
Touches the hilum of spleen
