Peritoneum Flashcards
What are the subdivisions of peritoneum?
- Parietal layer
2. Visceral layer (serosa)
What is peritoneum?
A serous membrane lining the cavity abdomen and covering the abdominal organs
Describe the parietal layer of the peritoneum
Lines the body wall and has abundant pain fibers via nerves from the body wall
Describe the visceral layer (serosa) of the peritoneum
Covers viscera and lacks pain fibers
What is between parietal and visceral layers of the peritoneum?
peritoneal cavity
Define mesentery
Double layers of visceral peritoneum. So they lack pain fibers
They are called reflections: part of peritoneal lining that is not right against the body wall or the organ. It is between organs. Most of the time it is suspending an organ from the body wall.
Why are mesenteries important?
They keep things in place, maintain relationships among structures in the abdominal cavity. Transmit major vessels and nerves.
What are intraperitoneal organs?
organs covered on most sides by visceral peritoneum
Suspended by mesentery from the body wall
What are retroperitoneal organs?
Organs that lie deep to the parietal peritoneum and are covered by parietal peritoneum on one side only (so they do not have any mesentery)
What are examples of intraperitoneal organs-have a mesentery and are completely covered by the peritoneum?
In the abdominal peritoneal cavity: Stomach Small intestine Spleen Liver Gallbladder Cecum Large intestine
Pelvic peritoneal cavity:
Uterus
Ovaries
Uterine tubes
What are the retroperitoneal organs?
Primarily:
Kidneys, suprarenal glands, uterine cervix, ureters, gonads, aorta and inferior vena cava
Secondarily:
Duodenum (descending, horizontal, and ascending)
Ascending and descending colon
Pancreas and rectum (upper 2/3)
What is the nerve supply to the peritoneum?
Nerves from the adjacent body wall supply parietal peritoneum. The nerves supply pain and vasomotor fibers
What is the difference between primarily retroperitoneal and secondarily retroperitoneal?
Secondarily retroperitoneal became retroperitoneal during development
What are the three main types of peritoneal reflections in adults?
Mesenteries
Ligaments and folds
Omentum
What are peritoneal reflections?
Parts of peritoneal linings that are not against body wall or an organ, but sort of “hangs out” between structures in the abdomen
What are mesenteries?
2-layered fold of peritoneum
What is THE mesentery?
Attaches the “free” small intestine (jejunum and ileum) to the posterior body wall
Define transverse mesocolon
Mesentery of the transverse colon
Holds the transverse colon to the posterior body wall
Fuses with the posterior layer of the greater omentum
Define sigmoid mesocolon
Mesentery of the sigmoid colon
Holds the sigmoid colon to the posterior body wall
What is mesoappendix?
Mesentery of the vermiform appendix