Peritneum and Mesentaries Flashcards
What is the peritoneum?
Peritoneum is a transparent serous membrane that lines the [abdominopelvic cavity] and surrounds the viscera (internal organs)
The peritneum has two different layers. What are these layers?
- Parietal peritoneum lines the abdominopelvic cavity
- Visceral peritoneum surrounds the organs
Describe the parietal peritoneum.
lines:
innervation:
sensitive to:
- lines the abdominopelvic wall
- innervated by the same [BV, nerves, lymphatics] as the region of the wall it lines
- sensitive to pressure, pain and temperature; pain here is localized
Describe the visceral peritoneum:
lines:
innervation:
sensitive to:
- Lines: surrounds organs
- Innervated: same BV, nerves, LN as the organ it surrounds
- sensitive to: stretch and chemicals; pain here is poorly localized.
What is intraperitoneal?
Most completely covered with VISCERAL peritneum
Retroperitoneal means ?
outside the peritoneal cavity and are only partially covered with peritoneum.
Retroperitoneal means outside the peritoneal cavity and are only partially covered with peritoneum.
What is the difference between primary and secondary?
Primary retroperitoneal means they were NEVER covered in a mesentery
Secondary retroperitoneal USED to be covered in mesentery
what are the organs that are retroperitoneal in SAD PUCKER?
- S- supraadrenal glands
- A- aorta/IVC *
- D- duodenum (2-4) +
- P- pancreas (not the tail)+
- U- ureters*
- C- colon (ascending and descending colon) +
- K- kidneys *
- E- ESO
- R-rectum
- means secondary * means primary
As the stomach rotates, you get the greater omentum (dorsal mesentery folds on itself),
as well as the space behind the liver and stomach called the?
Omental bursa (lesser sac)
What does the falciform ligament connect?
From the ventral mesentary: connects the liver –> anterior body wall.
What does the splenorenal ligament connect?
- From: dorsal mesentary
- Connects: posterior body wall (in front of kidney) –> spleen
Lesser omentum is from the ventral mesentary.
What are its 2 ligaments?
- Heptogastric ligament
- Hepatoduodenal ligament (has the portal triad inside: goes from liver–> 1st part of duodenum)
Greater omentum is from the dorsal mesentary.
What are the 3 ligaments from it? (all from dorsal mesentary)
- Gastrophrenic L: stomach–> diaphragm
- Gastrosplenic L : stomach to spleen
- Gastrocolic L: stomach–> transverse colon
Lesser omentum ligaments:
- hepatoduodenal L (3)
- hepatogastric L (2)?
What are their blood supplies?
- Hepatoduodenal L–> Proper hepatic a with two branches: cystic a and right gastric a
- Hepatogastric L–> L and R gastric A (they will anastomose)
Whats the blood supply in the greater omentum ligaments:
- Gastrophrenic L
- Gastrosplenic L
- Gastrocolic L
- Gastrophrenic L-
- Posterior gastric A.
- Gastrosplenic L-
- Short gastric A
- L gastro-omental A (aka L gastroepiploic A)
- Gastrocolic L-
- L gastro-omental A
- R gastro-omental A.
What supplies the splenorenal ligament?
splenic A
What supplies the transverse mesocolon? (2)
1. Middle colic A
2. Marginal A
What supplies the mesentary?
- Ileul A.
- Jejunal A.
- Superior mesentaric A.
What supplies the ROOT of the mesentery?
Also, what is the root of the mesentary?
Root is where the mesentary attaches to the posterior abdominal wall.
1. Iliocolic A
What supplies the sigmoid mesocolon?
sigmoid A
Where does the lesser sac (omental bursa) sit behind?
Lesser omentum, which is made up of the [hepatoduodenal L and the hepatogastric L].
Where does the greater sac sit behind?
Greater omentum, which is made up of the
- Gastrophrenic L
- Gastrosplenic L
- Gastrocolic L
The lesser sac (omental bursa) which sits behind the lesser omentum, communicates with the greater sac, which sits behind the greater omentum via the?
epiploic foramen (omental foramen)
What are the boundaries of the epiploic foramen?
Anterior
Posterior
Superior
Inferior
- Anterior: Hepatoduodenal ligmanet and its portal triad
- Posterior: IVC and R crus of the diaphragm
- Superior Caudate L of the liver
- Inferior: 1st part of the duodenum
What does the portal triad consist of? which is inside the hepatoduodenal ligament
1. Common bile duct
2. HPV
3. Proper hepatic artery
What is the pringle maneuver?
Placing fingers into epiploic foramen, and cutting off blood supply to portal triad in the hepatoduodenal ligament
-helps control bleeding of the liver
What are the 6 general boundaries of the lesser sac?
- Anterior
- Posterior
- Superior
- Inferior
- L
- R
What is anterior to the lesser sac? (3)
- lesser omentum
- stomach,
- gastrocolic ligament
What is posterior to the lesser sac? (6)
- IVC
- Aorta
- Splenic A and V
- L kidney
- L supradrenal gland
- Pancreas
What is superior to the lesser sac or omental bursa? (2)
- Liver
- Diaphragm
What is inferior to the omental bursa? (2)
- transverse mesocolon,
- 1st part of duodenum
What is to the left of the lesser sac? (2)
- hilum of spleen,
- gastrosplenic ligament
What is to the right of the lesser sac? (1)
- epiploic foramen into the greater sac
Why is the lesser sac good to have if the pancreas were to rupture anteriorly, or if the stomach were to rupture posteriorly?
the contents would be contained within the lesser sac instead of within the entire abdomen
What occurs if there is intestine in the lesser sac? Can any of it’s boundaries be cut to release the intestines?
NO, because the portal triad, IVC, aorta cannot be cut… you must pull them out with your hands
The transverse mesocolon divides the cavity into two compartments.
What are they?
1. Supracolic compartment
2. Infracolic compartment
The transverse mesocolon divides the cavity into two compartments… the supracolic and the infracolic compartment. What is contained in each? (3/3)
- Supracolic compartment–> stomach, liver and spleen
- Infracolic compartment–> SI, ascending colon and descending colon
The infracolic compartment can then be further divided.
By what and how do these two parts comunicate?
- Infracolic compartment can be divided by the root of the mesentary of the small intestine into: right infracolic space and left infracolic space.
- Communicate via the left and right paracolic gutters
When a patient is lying down, fluid would most likely reside in what two spaces that are divided by the falciform ligament?
right and left subphrenic spaces (from the lesser sac)
when the patient sits up, fluid will travel on either side via?
Why is one side more narrow than the other?
- down via the right and left paracolic gutter.
- Left side is more narrow due to the phrenicocolic ligament
When the patient is sitting / standing all the way up, fluid will collect in the pelvis, what is the space called in males and females?
Deepest space it can accumulate in.
- males: rectovesicular pouch
- females: rectouterine pouch
Large invasive, open incision are more painful because the peritoneum is exposed. What causes adhesions in the peritoneum?
when the area is touched, it is very sensitive; try to stay out of peritoneum
What is peritonitis and how is it caused?
infection of the peritoneal cavity caused by rupture of infected organ or external trauma, leading to abscesses
What is acites?
excess fluid in the peritoneal cavity due to cancer/malnutrition
Paracentesis is used to drain the extra fluid…
where is the best place to place the needle?
AWAY from the inferior epigastric A,
at the most inferior point of the rectouterine/vesicular pouch
What vertebral level is the head and tail of the pancreas at?
starts at L2 to L1 (transpyloric plane)
what are the areas of the pancrease
1. Head (uncinate process)
2. Neck
3. Body
4. Tail
What is anterior to the pancreas? (2)
lesser sac and stomach
What is posterior to the pancreas? (8)
- Aorta
- IVC
- Splenic Vein
- Bile duct
- right crus of the diaphragm
- left kidney and vessels
- left suprarenal gland
- superior mesenteric A/V
What is to the R of the pancreas
2nd part of the duodenum (it is craddled by it)
What is to the left of the pancreas? (2)
spleen,
What is inferior to the pancreas? (1)
3rd part of the duodenum
The superior mesenteric artery and vein run posterior to the pancreas. Why is this a clinical significance?
Due to how the pancreas is located, the uncinate process goes around the SMA/V.
if the cancer grows around the vessels, surgery cannot be performed :(
What are the primary retroperitoneal structures?
1. aorta/IVC
2. kidneys
3. ureters
What are the secondary retroperitoneal structures?
- ascending and descending colon
- duodenum 2-4
- pancreas (not the tail because it is intraperitoneal)
