L19-Abdominal Contents Flashcards
What is the mesentery?
A double layer of peritoneum that forms from the invagination of the peritoneum by an organ
What is the function of the mesentery?
Suspends the organs and provides pathways for the neurovasculature communication between the viscera and body wall
Where do the mesenteries originate from?
The visceral layer of the lateral plate mesoderm
The dorsal mesentery does what in the embryo?
Suspends the primitive gut tube from the posterior abdominal wall
The ventral mesentery develops where in the embryo?
In the foregut only: -lesser omentum -falciform ligament
Where can you find the parietal peritoneum?-
covers internal walls of the abdominopelvic cavity
What is the innervation of the parietal peritoneum?
Somatic from the lower thoracic and lumbar anterior rami -refer pain, temperature and touch
Where can you find the visceral peritoneum?
It invests GI organs
What is the innervation of the visceral peritoneum?
The same innervation as the organ it is covering -autonomic (pain poorly localized)
Where can you find the retroperitoneal space? What does it contain?
posterior to the peritoneal cavity -contains fat, vessels, and few organs
Identify
a:
b:
c:
Peritoneal Folds: Peritoneum that is reflected away from the abdominal wall by functional or obliterated fetal vessels
a: Lateral umbilical fold
b: Medial Umbilical fold: obliterated umbilical aa.
c: Median umbilical fold
What are the borders of the foregut? What can you find in this location?
From the oropharyngeal membrane to the proximal duodenum -esophagus, stomach, proximal duodenum, liver, gallbladder and pancreas
A what level does the abdominal esophagus pass through the esophageal hiatus?
At T10
What sphincter is between the stomach and esophagus?
Cardiac sphincter
What are the two types of hiatal hernias? Where can you find them?
Find them between the stomach and the esophagus
- sliding hiatal hernia: abdominal esophagus, cardia of stomach slides through the esophageal hiatus
- paraesophageal: herniation of fundus of stomach, cardiac orifice stays in normal position
Name the regions of the stomach
- Black: Cardia
- Red: Fundus
- Green: Body
- Yellow: Pyloric antrum
- Blue: Pyloric canal
What can you find between the stomach and the duodenum?
The pyloric sphincter
How does the stomach develop in utero that gives it its shape?
Through both rotation and differential growth -rotates 90 degrees clockwise
- anterior side grows more slowly: lesser curvature
- posterior side grows more rapidly: greater curvature
What nerve rotates with the stomach?
Vagus
What are the mesenteries associated with the stomach called? Where can you find them?
- Lesser omentum: between stomach/proximal duodenum
- Greater omentum: hangs inferiorly from stomach from greater curvature to transverse colon
What does the greater omentum of the stomach prevent?
Adhesion of viscera anterior abdominal wall
What are the two components of the lesser omentum?
- Hepatogastric ligament: stomach to liver
- Hepatoduodenal ligament: duodenum to liver; portal and biliary systems
What can you find posterior to the right edge of the hepatoduodenal ligament?
the omental foramen
What is acid reflux?
regurgitation of gastric acids into lower esophagus
what are gastric ulcers?
open lesions of the mucosa of the stomach (leaves stomach susceptible to H. pylori)
Where can you find the pyloric stenosis? What is it/what is a consequence?
- At the narrowing of the pyloric canal
- it’s the thickening of the smooth muscle of the pyloric sphincter
- resists gastric emptying
What are the functions of the spleen?
filters blood, removes redundant RBCs, largest lymphoid organ
Where can you find the spleen?
Deep to left ribs 9-11
What runs through the hilum of the spleen?
splenic artery and splenic vein
What is splenomegaly? What can cause it?
an enlargement of the spleen due to increased workload
- portal hypertension
- leukemia, lymphoma
- blood diseases
- chronic infections
What are the functions of the liver?
Roles in
- metabolism
- filtering blood
- bile production
- hormones
- glycogen storage
How many lobes does the liver have? Name them
4:
- right lobe
- left lobe
- caudate lobe
- quadrate lobe
Where can you find the porta hepatis? What runs through it?
- Between the caudate and quadrate lobes of the liver
- Running through it:
- The proper hepatic artery
- portal vein
- hepatic ducts
Name the two peritoneal ligaments of the liver. What do they connect to?
- Falciform ligament: liver to anterior abdominal wall
- Round ligament: obliterated umbilical vein
When bile backs up in the common bile duct, where does it drain?
Into the cystic pancreas via the cystic duct
What makes up the triangle of calot?
- the cystic duct
- common hepatic duct
- cystic artery
What are a concretion of cholesterol crystals in the gallbladder called?
Gallstones
What develops as an outgrowth of hepatic diverticulum of the distal foregut?
The liver (gallbladder develops as a secondary growth to the liver)
What causes the liver to deviate to the right side?
It grows quickly and superiorly to contact the septum transversum (septum transversum turns into the developing diaphragm and ventral mesentery)
What causes the bare area of the liver?
In development, the visceral peritoneum obliterates in area of contact. No mesentary present
What is the duct of the pancreas called?
pancreatic duct (accessory duct comes off of it)
Where can you find the major duodenal papilla?
Common opening into the duodenum
What are the two pancreatic buds in development called?
- dorsal pancreatic bud (larger/appears first)
- ventral pancreatic bud (near entry of bile duct)
What causes the two buds of the pancreas to come together during development?
Rotation, ventral bud twists dorsally to join the dorsal bud
At what level does the abdominal aorta transverse the diaphragm?
At T12
At what level does the abdominal aorta bifurcate? What arteries does the abdominal aorta bifurcate into?
- at L4
- Bifurcates into right and left common iliac aa.
What three branches come off of the celiac trunk?
- Left gastric a
- splenic a
- common hepatic a
* celiac trunk: blood supply to foregut
The right hepatic artery is found where?
right side of the liver
The cystic artery runs to what?
gallbladder
The left hepatic artery can be found where?
Left side of liver
The right gastric artery runs where?
lesser curvature of the stomach
Name the four arteries that supply the stomach
- Left gastric A
- Right gastric A
- Left gastro-omental A
- Right gastro-omental A
Name the four arteries that supply the pancreas?
- Gastroduodenal
- direct branches from splenic artery
- superior pancreaticoduodenal aa
- inferior prancreaticoduodenal aa
Blood from the digestive system must run through what to return to the systemic circulation?
The portal system (liver) via the hepatic portal vein
What makes up the portal triad?
- The proper hepatic artery
- bile duct
- hepatic portal vein
Hepatic veins drain into what?
The IVC after it has been filtered
Common Hepatic Artery divides into what two arteries?
- Proper hepatic artery
- Gastroduodenal artery
The paraumbilical veins usually drain into what system?
portal system
If the portain vein is obstructed, where will the the blood from the paraumbilical veins drain? What is the result of this?
Blood will back up into the superficial epigastric veins that eventually lead to the IVC.
Esophageal veins superior to the diaphragm drain into what system?
Into the azygos system and ultimately to the SVC
Esophageal branches (veins) inferior to the diapragm drain into what system?
Into the portal system via the left gastric vein
If there is backup of blood in the portal system, where will the blood from the left gastric ultimately drain? Why is this dangerous?
Will back up and travel up to the azygos/caval system via the superior esophageal veins. The esophageal veins are relatively weak and can rupture causing serious problems/potential for bleeding out
The foregut lymph drains into what lymph nodes?
Celiac lymph nodes ->chyle cistern -> thoracic duct
