abdominal cavity and peritoneum

Question 1

The abdominal cavity is part of the abdominopelvic cavity. The abdominal cavity contains a serous sac, the peritoneum, which is similar to pleura and pericardium. The abdominal cavity contains organs of the digestive and urinary systems, which are located where in regards to the peritoneum?

Answer 1

They invaginate the peritoneum or are located behind it (such as the kidneys).

Question 2

What is the difference in the peritoneal cavity in males and females, and why is this clinically relevant?

Answer 2

The peritoneal cavity is a closed sac in males, but in females the vagina, uterus, and uterine tubes connect the peritoneal cavity with the outside world! This is a potential pathway for the spread of infection.

Question 3

The peritoneal cavity normally contains only a thin film of peritoneal fluid.

In some pathological conditions (ex: cirrhosis of the liver, chronic heart failure, ovarian cancer) excess peritoneal fluid accumulates. This condition is known as…………

Excess fluid may be removed for diagnostic or therapeutic purposes in a procedure called………………

Answer 3

ascites

paracentesis

Question 4

Bacteria may infect the peritoneum (such as after a penetrating wound or a peptic ulcer) , causing inflammation called……………., resulting in severe abdominal pain and tenderness, nausea and vomiting, fever, and constipation.

Why is this a potentially a life-threatening condition?

Answer 4

peritonitis

due to the peritoneum’s large surface area and the rapid absorption of bacterial toxins

Question 5

Peritoneal fluid normally flows SUPERIORLY, toward the diaphragm, and is rapidly absorbed! So, how would you position a patient who has bacterial peritonitis?

Answer 5

propped in a seated position (≥ 45°) so that:

• the infected fluid flows downward into the pelvic cavity, where absorption is slower.
• the likelihood of infection spreading through the diaphragm to the pleura from the subphrenic space is reduced.

Question 6

Peritonitis due to trauma (ex: surgery) or infection may result in the formation of…………………., which can cause chronic pain and bowel or uterine tube obstruction!

Answer 6

peritoneal adhesions (fibrous bridges)

Question 7

Organs of the abdominal cavity are related to peritoneum in one of two ways: Intraperitoneal or Retroperitoneal. Describe each:

Answer 7

• Intraperitoneal: invaginating the peritoneal sac from behind and suspended from the body wall by a double layer of peritoneum (mesentery).
• Retroperitoneal: located posterior to the peritoneum

Question 8

Intraperitoneal organs have a covering of…………….. peritoneum and are suspended by a……………

Answer 8

visceral

mesentery

Question 9

the peritoneum lining the body wall is………….. peritoneum.

Answer 9

parietal

Question 10

Blood vessels and nerves that supply an intraperitoneal organ reach it through a………………….

Answer 10

mesentery

* some mesenteries are named according to specific parts of the digestive tract (ex: transverse mesocolon to transverse colon), but that to the small intestines is called simply “the mesentery.”

Question 11

Retroperitoneal organs are posterior to the parietal peritoneum, located between it and the posterior abdominal wall. Therefore they are only partially covered by parietal peritoneum, usually just on the anterior surface. An example is what organ?

Answer 11

Kidneys

Question 12

The Intraperitoneal organs:

Answer 12

• Abdominal esophagus
• Stomach and proximal duodenum (duodenal cap)
• Jejunum and ileum
• Cecum
• Transverse colon
• Sigmoid colon
• Liver and gallbladder
• Tail of the pancreas
• Spleen

Question 13

The retroperitoneal organs:

Answer 13

• Duodenum (except the duodenal cap)
• Ascending colon
• Descending colon
• Pancreas (except the tail)
• Kidneys and ureters
• Abdominal aorta
• Inferior vena cava

Question 14

Peritoneal formations consisting of double layers of peritoneum include:

Answer 14

• Mesenteries
• Omenta (which connect the stomach & proximal duodenum to other organs)
• Peritoneal ligaments (which connect abdominal organs to each other or to the abdominal wall)

Question 15

An omentumis a double-layered fold of peritoneum passing from the stomach & proximal duodenum to adjacent organs. There are two omenta:

Answer 15

• Greater omentum: suspended from the greater curvature of the stomach
• Lesser omentum: connecting the lesser curvature

Question 16

What is cool about the greater omentum?

Answer 16

The greater omentum is mobile and often moves to wall off infections within the peritoneal cavity, keeping them localized to prevent generalized peritonitis!

Question 17

A…………. ligament is a double layer of peritoneum that connects an abdominal organ with another organ or with the abdominal wall.

Answer 17

peritoneal

Question 18

Some peritoneal ligaments are parts of the greater or lesser omentum (such as the………………. ligament), while some peritoneal ligaments connect an organ to an adjacent organ (such as the…………….. ligament) or the body wall.

Answer 18

gastrosplenic

splenorenal

Question 19

peritoneal formations (and some organs) join to subdivide the peritoneal cavity. What are the different sacs of the peritoneal cavity that they form?

Answer 19

• Greater sac (which is the main, larger part of the peritoneal cavity)
• Lesser sac, called the omental bursa (which lies posterior to the stomach and lesser omentum)

* The blue in the pic is the lesser sac.

Question 20

The greater peritoneal sac and omental bursa communicate through the……….. foramen.

Answer 20

omental (epiploic)

Question 21

The omental foramen is bounded anteriorly by:

Answer 21

the hepatoduodenal ligament, which forms the free right edge of the lesser omentum.

Question 22

The omental foramen is bounded posteriorly by:

Answer 22

the inferior vena cava

Question 23

The omental foramen is bounded superiorly by:

Answer 23

caudate lobe of the liver

Question 24

The omental foramen is bounded inferiorly by:

Answer 24

the superior (first) part of the duodenum

Question 25

What is an important clinical note to remember about the omental foramen?

Answer 25

The omental foramen is occasionally the site of an internal hernia when a loop of small intestine becomes entrapped within it; since none of the boundaries of the foramen can be incised, the swollen intestine must be decompressed with a needle to free it.

Question 26

The greater peritoneal sac is subdivided by what?

Answer 26

the transverse colon and transverse mesocolon

Question 27

Thegreater peritoneal sac is subdivided by the transverse colon andtransverse mesocolon into what compartments?

Answer 27

• Supracolic compartment containing the stomach, liver, and spleen
• Infracolic compartment containing the small intestine, ascending colon, and descending colon.

Question 28

The infracolic compartment is subdivided by the mesentery of the small intestine into which spaces?

Answer 28

• Right infracolic space
• Left infracolic space

Question 29

The abdominal cavity communicates with the pelvic cavity, providing pathways for the spread of infection or cancer cells! This is done via the:

Answer 29

• Right paracolic gutter (lateral to the ascending colon; it connects the supracolic compartment and pelvic cavity)
• Left paracolic gutter (lateral to the descending colon)

Question 30

The lowest part of the abdominal portion of the peritoneal cavity in the supine position is the……………………… between the right lobe of the liver and the right kidney.

Answer 30

hepatorenal recess (Morison’s pouch)

* hepatorenal recess communicates medially with the omental bursa (through the omental foramen) and anteriorly with the subphrenic recess (between the liver and diaphragm), a common site for abscesses. Therefore, infected fluid can easily enter the hepatorenal recess from the omental bursa or subphrenic recess.

Question 31

The internal surface of the anterolateral abdominal wall contains………. umbilical folds.

Answer 31

5

* two on each side of the umbilicus and one in the median plane.

Question 32

The……………. umbilical fold extends from the apex of the urinary bladder to the umbilicu. It covers the median umbilical ligament (urachus).

Answer 32

median

Question 33

The depression lateral to the umbilical folds are the peritoneal fossae or recess. They are potential sites of…………….

Answer 33

hernias

Question 34

Two medial umbilical folds are located lateral to the median umbilical fold, and cover the……………….

The two lateral umbilical folds are lateral to the medial umbilical folds, and cover the inferior epigastric vessels.

Answer 34

medial umbilical ligaments (occluded parts of umbilical arteries)

Question 35

The…………….. fossae is located between the median & medial umblicalfolds.

Answer 35

Supravesical

Question 36

The……………….. fossae is located between the medial and lateral umbilical folds.

Answer 36

Medial inguinal

Question 37

The…………………. fossae are located lateral to the lateral inguinal folds.

Answer 37

Lateral inguinal