Peritoneum Flashcards
What is the peritoneum?
a thin transparent serous membrane lining abdominopelvic cavity and clothing the viscera
Describe the layers of the peritoneum?
- parietal - lines abdominal wall
2. visceral - closely covers viscera
What is the peritoneal cavity?
potential space between the parietal and visceral peritoneum filled with peritoneal fluid
Function of peritoneal fluid?
the serous fluid lubricates peritoneal surfaces - facilitates free movement between viscera
What is extraperitoneal tissue?
layers of connective tissue between parietal peritoneum and the abdominal wall - has fat
Where is the abdominopelvic cavity located?
between thoracic diaphragm and pelvic diaphragm
What are the 2 transverse planes?
- subcostal - passing through the inferior limits of the costal margin : 10th costal cartilages 2. transtubercular plane - passes through the iliac tubercles
What are the 2 vertical planes?
midclavicular planes
What are the 6 regions the cavity is divided into by the planes?
- right and left hypochondriac 2. epigastric 3. umblical 4. pubic 5. right and left lumbar 6. right and left inguinal
What are the retroperitoneal organs?
- Part of Duodenum 2. ascending colon 3. descending colon 4. pancreas 5. kidneys 6. ureters 7. IVC 8. aorta
What are the intraperitoneal organs?
- stomach 2. spleen 3. jejunum
Describe the peritoneal cavity in males?
closed
Describe the peritoneal cavity in females?
peritoneal cavity communicates with exterior through uterine tubes, uterus and vagina
Describe the greater sac?
the main peritoneal cavity - surgical incision through anterior abdominal wall enters this sac
Describe the lesser sac?
recess posterior to the stomach
What is the omental foramen? (foramen of Winslow)
links greater and lesser sacs
What are the boundaries of the foramen of Winslow?
- anterior - free border of lesser omentum 2. posteriorly - inferior vena cava 3. superiorly - caudate process of caudate lobe 4. inferiorly - first part of duodenum
What are the types of peritoneal folds?
- mesentery 2. omentum 3. ligament
What is the mesentery?
2 layered fold of peritoneum that attaches intestines to posterior abdominal wall e.g. mesentry of small intestines
Function of mesentery?
permit an intestine to be free and mobile
What is an omentum?
a 2 layered fold of peritoneum that attaches the stomach to another viscus e.g. greater omentum, lesser omentum, & gastrosplenic omentum (ligament)
What are peritoneal ligaments?
2 layered folds of peritoneum that attach viscera to another (usually less mobile) viscera or to abdominal wall e.g. falciform ligament of liver
Function of ligament?
restricts mobility by attaching a viscus to another viscus (usually less mobile viscus) or wall
What is the peritoneal recess or fossa?
a pouch of peritoneum that is formed by a peritoneal fold e.g. the inferior recess of the omental bursa between the layers of the greater omentum
What are paracolic gutters?
arrangement of ascending & descending colon, attachments of trans. Colon and mesentery of small intestines to posterior abdominal wall – results in formation of 4 gutters : 2 meadial and 2 lateral to ascending and descending colons
What is the function of gutters?
form communication pathway between abdominal cavity compartments
Describe the right medial paracolic gutter?
closed off from pelvic cavity by small intestine mesentery
Describe the left lateral paracolic gutter?
closed from subphrenic region by phrenicocolic ligament (fold of peritoneum)
What are the functions of the greater omentum?
- stores fat 2. cushions viscera 3. supports lymph nodes 4. protects against spread ofinfections - can compartmentalize inflamed area e.g. in appendicitis
Describe the dorsal mesentry?
- supports GIT 2. gives small intestine freedom for peristaltic movement 3. provides structure through which intestinal nerves & vessels traverse
What is the transverse mesocolon?
mesentry of transverse colon
What is the mesoappendix?
mesentry supporting appendix and its vessels
What is the falciform ligament?
- extension of parietal peritoneum reinforced with connective tissue 2. attaches liver to diaphragm & anterior abdominal wall
Describe the lesser omentum?
passes from lesser curvature of stomach & upper duodenum to inferior surface of liver ( hepatoduodenal & hepatogastric)
Describe the greater omentum?
- extends from greater curvature of stomach to transverse colon 2. forms an apron like structure over most of small intestines
The parietal peritoneum is sensitive to?
- pain 2. touch 2. pressure 4. temperature
Describe the innervation of the parietal peritoneum?
- Lateral & anterior wall parts (same nerves as overlying muscles) – thoraco-abdominal nerves (T7 –T12 + L1) 2. Central parts (diaphragmatic)- phrenic nerves 3. Peripheral diaphragmatic - T7 – T12 4. Pelvis - obturator nerve
The visceral peritoneum is sensitive to?
stretch
The visceral perironeum is supplied by?
autonomic afferent nerves
What are the functions of peritoneum?
- Ensures that mobile viscera glide easily upon each other – (peritoneal fluid – lubricant) 2. Defense against infection - Peritoneum coverings of intestines tend to stick together in the face of infections (to seal off infection) 3. Peritoneal folds serve an important role in suspending viscera & serve as a means to convey neurovascular structures to the viscus 4. Storage of fats - Large amount of fat are stored in the peritoneal folds - esp. greater omentum
What is peritonitis?
inflammation of the membrane lining the abdominal wall and covering the abdominal organs
