Flashcards in Ach: Disposition of the Peritoneum Deck (75):
What is the peritoneum?
Secretory serous membrane that secretes a SMALL amt of fluid for lubrication between surfaces of organs that extend into it
What is the peritoneum derived from?
Mesenchymal cells of the embyronic mesoderm
Where does the peritoneum line?
Perioneal cavity (the largest serous cavity in the body) located in the abodominopelvic cavity
What is the difference between the peritoneal cavity in a male vs. female?
Male- completely closed
Female- communicates w/ the exterior via the openings of the uterine tubes
What is the parietal peritoneum?
Lines the WALLs of the abdominal cavity and upper surfaces of the pelvic cavity; reflects of the vertebral column
What is outside the parietal layer of the parietal peritoneum?
Layer of CT called the extraperitoneal layer that is FATTY
What is the visceral peritoneum?
Covers the ORGANS suspended in the abdominal and pelvic cavities
What is hte fate of the somatic mesoderm when the trilaminar disk folds?
Becomes the trunk wall, lined w/ parietal paritoneum
What is the somatic mesoderm continuous?
Splanchnic mesoderm located at the dorsal and ventral mesenteries; walls of the foregut and the visceral peritoneum
What does the dorsal mesentery consist of?
two layers of parietal peritoneum; continuous w/ ventral mesentery (also two layers of peritoneum)
What is the yolk sac made up of? What is it continuous with?
Endoderm of the viscera
Continuity at the umbilicus
What is hte intraembryonic coelom lined by?
What is the intraembryonic coelom divided into?
LEFT and right abdominal cavities by dorsal and ventral mesenteries
How does growth and rotation of the primitive gut tube change the geometry of the mesenteries and peritoneal cavity?
RIGHT side of the peritoneal cavity comes to lie BEHIND the ventral mesentery, stomach and liver
What are the two divisions of the peritoneal cavity?
Lesser sac (omental bursa)
What is the main compartment of the peritoneal cavity? Where does it extend to?
Extends across the abdomen from the diaphragm to the pelvis
Organs that extend into the greater sac are...
Peritoneal or intraperitoneal
What sac is formed as a result of rotation of the gut?
Where is the lesser sac located?
Smaller, lies behind the stomach, liver, lesser omentum and part of the greater omentum
How does the lesser sac communicate w/ the greater sac?
What is the mesentery?
A two layered fold of peritoneum that attaches part of the intestine to the posterior abdominal wall and permits the intestine to be mobile. It also serves as CONDUIT for blood vessels and nerves attached to the organ.
What are examples of mesentery?
Mesentery of the sml intesetine
What is the omentum?
Two layered fold of peritoneum that attaches the stomach to another organ
What is the greater omentum?
Stomach to transverse colon; four layers and potential space
What is the lesser omentum?
Stomach to liver
What are the peritoneal ligaments?
Two layerd fold of pertioneum that attaches a less mobile, solid viscera to the abodominal wall or other organs
What attaches the liver to the abdominal wall?
What attaches the spleen to the posterior wall at the level of hte kidney?
What attaches the liver to the inferior diaphragm?
Mesenteries or ligaments that extend from the ANTERIOR body wall are derived from...
Mesenteries or ligaments taht extend from the POSTERIOR body wall are derived from...
What are retroperitoneal or extraperitoneal organs?
Ones that develop OUTSIDE the peritoneal cavity
*viscera are covered w/ peritoneum and have NO free mesenteries are retroperitoneal
What is the falciform ligament?
A double layer of peritoneum extends between the anteiror abdominal wall and the anterior surface of the liver
What does the falciform ligament enclose?
Ligamentum teres (remnant of the FETAL LEFT UMBILICAL VEIN)
What does hte right lamina of the falciform ligament form?
Anteiror layer of the coronary ligament
What does the posterior layer of the coronary ligament enclose?
The bare area of the liver
What forms the left triangular ligament?
The left lamina of the falciform ligament
What forms the lesser omentum?
2 layers of visceral peritoneum reflecting off of the liver forming a ligament between the liver and stomach and liver and duodenum
What are hte subdivisions of the lesser omentum?
1. Hepatoduodenal ligament
2. hepatogastric ligament
What is the hepatoduodenal ligament?
porta hepatis to the first inch of duodenum
What does the hepatoduodenal ligament enclose?
1. common bile duct
2. hepatic artery
3. portal vein
What forms the anterior border of the epiploic foramen?
What is the hepatogastric ligament?
Encloses the right and left gastric arteries
Extends from the fissure of the ligamentum venosum near the porta hepatis to the lesser curvature of the stomach
What does hte great omentum cover?
It extends INFERIORLY from the greater curvature of the STOMACH over the coils of intestine then doubles up on itself to form a four layered structure that attaches to the TRANSVERSE COLON.
What are the three parts of the greater omentum?
What encloses the right and left gastroepiploic vessels?
The greater omentum
What extends from the hilus of the spleen to the fundus of hte stomach?
What does hte gastrosplenic ligament enclose?
Short gastric vessels
What extends from the parietal peritoneum over the kidney to the hilus of the spleen?
What encloses the splenic vessels?
What extends from the posterior abdominal wall and suspends the transverse colon?
What does the transverse mesocolon enclose?
middle colic vessels (branches of the superior mesenteric a.)
What exetends from the posterior abdominal wall and suspends the sigmoid colon?
What does the sigmoid colon enclose?
sigmoid colon vessels (branches of the INFERIOR mesenteric a.)
Where is the mesentery of the small intestine?
It extends about 15 cm diagonally along the posterior abdominal wall from the cecum to the duodenojejunal flexure.
What does the mesentery of the small intestine suspend?
Jejunum and ileum from the posterior abdominal wall
What encloses the intestinal and ileocolic vessels?
Mesentery of the small intestine
What are the peritoneal recesses?
spaces and channels defined by the peritoneum as it drapes over organs
Why is the clinical importance of peritoneal recesses?
Provide a route for pooling or flow of ascitic fluids, spread of cancer cells and infection
What are the channels w/in the peritoneal sac that lie lateral to the ascending and descending colon respectively?
Right and left paracolic gutters
Where are the right and left infracolic spaces?
Lie on either side of the root of the mesentery. The right infracolic is a closed space.
What is the hepatorenal recess?
A potential space bounded by the liver, R kidney, duodenum and colon. It represents the lowest point in the peritoneal cavity when the individual is supine.
What is the subphrenic recesses?
Bounded by the liver, falciform ligament and anterior abdominal wall. Abscesses in this recess may penetrate the diaphragm.
Where is the peritoneum located in reroperitoneal organs?
On the anterior surface
What does primary retroperitoneal refer to?
An organ's development entirely OUTSIDE the peritoneum
What organs are primary retroperitoneal organs?
1. kidneys, suprarenal glands, uterus, urinary bladder
2. aorta and IVC
3. Lumbar plexus and branches
What does secondary retroperitoneal refer to?
An organ's development IN hte peritoneal cavity that later becomes retroperitoneal
What organs are secondary retroperitoneal organs?
Duodenum, ascending colon, descending colon
What are organs called that remain w/in and develop in the peritoneal cavity?
What innervates the parietal peritoneum? What are they sensitive to?
Somatic afferent fibers (pain, touch, pressure)
1. Intercostal and subcostal nerves (T7-T12)
2. Phrenic nerves
3. Lumbar nerve (L1)
What innervates the visceral peritoneum? What are they sensitive to?
Visceral afferent fibers running with the ANS (sensitive to distention--> leads to the sensation of pain)
*Diffuse sensation that is difficult to localize
What are the functions of hte peritoneum?
1. Secrete serous fluid (ensure mobility of viscera)
2. Fat storage
3. Conduit for lymphatic, blood vessels and nerves
What happens to particulate matter that is introduced into the lower part of the peritoneal cavity and what does that indicate?
It reaches the SUBPHRENIC SPACES rabidly, no matter what position the body is in
This indicates that there is continuous intraperitoneal movement of fluid toward the diaphragm where it is absorbed into the lymphatics.
What is peritonitis?
Inflammation of the peritoneum (general or localized) which results in accumulation of serous fluid (ASCITES)