Lectures 4 and 5- Organs of GI tract Flashcards
The thoracic esophagus pierces the diaphragm at the level of what vertebra?
- What is this called?
- Where is it relative to midline?
T10
- Called the esophageal hiatus
- Slightly left of midline
After the esophageal hiatus, the esophagus turns sharply to the left to enter the stomach at the cardiac orifice
-At about the level of what vertebra?
T11
IVC pierces the diaphragm at the level of what vertebra?
T8
The aorta pierces the diaphragm at the level of what vertebra?
-pneumonic to remember these?
T12
-I ate 10 Eggs At Noon
ate = 8
“Sliding” hiatal hernia
- Esophageal hiatus of diaphragm enlarges or weakens
- Abdominal esophagus and parts of the stomach (cardia and sometimes fundus) herniate into the thorax
- Regurgitation of gastric contents
Paraesophageal hiatal hernia
- A defect in the diaphragm next to the esophageal hiatus
- Permits fundus of stomach to herniate (not usually the esophagus)
- No regurgitation of gastric contents
Stomach-located in what regions?
- Left upper quadrant
- Hypochondriac and epigastric regions
Stomach
- Left end is fixed at the level of what vertebra?
- Right end is fixed at the level of what vertebra?
- Left end (esophageal end) is fixed at T10-T11
- Right end (duodenal end) is fixed at L1-L2
Know the parts of the stomach
Slides 9 and 10
Pyloric orifice
Entrance to the duodenum
Surfaces of the stomach?
Slide 12
Things that are anterior to the stomach?
- Anterior abdominal wall
- Left costal margin
- Left diaphragm
- Left and quadrate lobes of liver
Small intestine-divided into 3 parts:
-Duodenum-general characteristics?
- C-shaped
- 10 in long
Duodenum
-Located approximately at what vertebral bodies?
Located approximately at L1-L4 vertebral bodies
Duodenum
- Where does it start?
- Where does it end?
Starts at the pylorus of the stomach and ends at the duodenal-jejunal junction
Duodenum
-Subdivided into 4 parts?
Superior, descending, horizontal, ascending,
Duodenum
-Secondarily retroperitoneal except for?
Some of the 1st and 4th parts
Duodenum
- Covered anteriorly by?
- Except where?
Covered anteriorly by the peritoneum except where the mesocolon of the transverse colon crosses the second part
Duodenum
-The first part is surrounded by what ligament?
Hepatoduodenal ligament
Duodenum
-The root of the mesentery begins at the?
Duodeno-jejunal flexure
Duodenum
- Features of the first part (superior)
- where does it start?
Starts at the pyloric sphincter
Duodenum
-Superior part of the duodenum is held in place by?
the hepatoduodenal ligament
Duodenum
-Where are the portal vein, hepatic artery, and bile duct located relative to the superior part of the duodenum?
the portal vein, hepatic artery, and bile duct are superior and posterior
Duodenal bulb
Widened area
Duodenum
-where is the head of the pancreas relative to the first part of the duodenum?
The head of the pancreas is inferior to the first part of the duodenum
-The head of the pancreas “sits inside the C” (the shape of the duodenum)
Which 2 parts of the duodenum are completely secondarily retroperitoneal?
The 2nd and 3rd (descending and horizontal)
Duodenum-Features of the 2nd part (descending)
-Anterior to the descending part?
the fundus of the gall bladder, right lobe of liver, transverse colon are all anterior to the descending duodenum
Duodenum
-Posterior to the descending part?
Right kidney and ureter
Where is the head of the pancreas relative to the 2nd part of the duodenum?
The head of the pancreas is medial to the descending duodenum
Descending part of the duodenum
-What enters into the major duodenal papilla?
The bile and pancreatic ducts
3rd part of the duodenum
-What 3 things cross the anterior surface?
- Superior mesenteric artery
- Superior mesenteric vein
- Root of the mesentery
Where is the head of the pancreas relative to the horizontal part of the duodenum?
The pancreas is superior to the horizontal part of the duodenum
Where is the jejunum relative to the horizontal part of the duodenum?
The jejunum is anterior and inferior to the horizontal part of the duodenum
4th part (ascending) of the duodenum
- Intraperitoneal (not covered by parietal peritoneum)
- Where are the root of the mesentery and jejunum relative to the ascending part of the duodenum?
the root of the mesentery and jejunum are anterior to the ascending part
Where are the left margin of the aorta and medial border of the psoas muscle relative to the ascending part of the duodenum?
The left margin of the aorta and the medial border of the psoas muscle are posterior to the ascending duodenum
The ascending duodenum is held in place by?
-What does it anchor the ascending duodenum to?
- The ascending duodenum is held in place by the suspensory ligament of the duodenum
- It anchors the ascending part of the duodenum to the right crus of the diaphragm
Jejunum and ileum
- Occupy most of the peritoneal cavity of the abdomen and pelvis
- Very mobile
Where does the jejunum begin?
Where does the ileum end?
- The jejunum begins at the duodenal-jejunal junction
- The ileum ends at the ileo-cecal valve
Jejunum and ileum
-Held to the posterior wall by?
THE mesentery
Which is longer-the jejunum or ileum?
Ileum
Jejunum-characteristics?
- Simple vascular arcades
- Long vasa recta
- More vascular
- Greater diameter, thicker
- More plicae circularis (folds)
Ileum-characteristics?
- Complex vascular arcades
- Shorter vasa recta
- Less vascular
- Smaller diameter, thinner wall
- Fewer plicae circularis