Peritoneal Cavity Flashcards
What is the peritoneum?
thin serous membrane
What does pariteal peritoneum line?
walls of the abdominal and pelvic cavities
What does the visceral peritoneum line?
viscera (organs)
What is the space between the pariteal and visceral peritoneum called?
peritoneal cavity
Describe the peritoneal cavity in males
completely closed
Describe the peritoneal cavity in females
there is potential indirect communication with the exterior
What is the peritoneal cavity divided into?
greater and lesser sacs
What does the peritoneal cavity secrete?
small amount of serous fluid known as peritoneal fluid
What is the function of peritoneal fluid?
lubricates the surfaces of the peritoneum to allow distension and free movement beyween the viscera (organs)
what are the three main structures formed by the peritoneum?
- omenta (greater and lesser)
- Mesenteries
- Ligaments (peritoneal folds)
What is the peritoneal cavity and what is it divided into?
biggest cavity in the body
- greater sac
- lesser sac
What is the greater sac?
main compartment extending from the diaphragm into the pelvis
What is the lesser sac?
lies posterior to the stomach and lesser omentum but extends slightly into the greater omentum
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red = greater sac
blue = lesser sac
What are the main properties of the peritoneal cavity?
- can be used for peritoneal dialysis and fluid administration
- spread of infections, cells or bleeding
Where is the lesser sac located?
posterior to the stomach and lesser omentum
How does the lesser sac communicate with the greater sac?
via epiploic foramen
Describe Pringle’s manouvre
During surgery the hepatic artery proper and portal vein can be compressed with fingers/haemostat to control bleefing
During surgery how can the lesser sac be approached?
via the epiploic foramen
Give 2 other names for the epiploic foramen
- omental foramen
- foramen of winslow
What is the anterior boundary of the epiploic foramen
- free border of lesser omentum, with the common bile duct
- hepatic artery
- portal vein
What is the posterior boundary of the epiploic foramen
inferior vena cava
What is the superior boundary of the epiploic foramen
caudate process of caudate love of liver
What is the inferior boundary of the epiploic foramen
first part of duodenum
Where is the lesser ometum derived from?
ventral mesentary
Where does the lesser omentum pass from?
lesser curvature of the stomach to the 1st part of duodenum to the inferior border of the liver
What can the lesser omentum be subdivided into?
hepatogastic and hepatoduodenal ligaments
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blue = hepatogastic
red = hepatoduodenal
What is the free edge of the lesser omentum?
hepatoduodenal ligamenent
What does the hepatoduodenal ligament contain?
portal triad
- hepatic portal vein
- hepatic artery proper
- common bile duct
Where is the greater omentum derived from?
dorsal mesentery
What is the greater omentum attached to?
greater curvature of the stomach and 1st part of the duodenum
How does the greater omentum hang?
like an apron anterior to the small intestine
What does the greater omentum consist of?
a double layer of visceral peritoneum folded upon itself
What does the greater omentum overlie?
transverse colon and much of the small intestine
What does the greater omentum contain?
fat and gastro-epiploic arteries and veins
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Greater omentum
What is mesentery?
tissue formed by a double layer of visceral peritoneum
What is the function of mesentery?
attach the abdominal organs to the posterior abdominal wall
What is mesentery derived from?
dorsal mesentery
What does mesentery act as conduits for?
blood vessels, nerves and lymohatics
What is ‘the mesentery’?
a fan-shaped double-layered fold of vsiceral peritoneum cinnbecting the jejunum to the posterior abdominal wall
Where does ‘the mesentery run’?
Its base starts just left of L2 and passes obliquely downwards to the right ending just above the right sacroiliac joint
How long is ‘the mesentery’?
approximately 20cm
What does ‘the mesentery’ cross?
crosses the 3rd part of the duodenum, the aorta & inferior vena cava, the right gonadal vessels & right ureter
What is contained within ‘the mesentery’?
are branches of the superior mesenteric vessels, nerves & lymphatics
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the mesentery
What is the sigmoid mesocolon?
Double-layered fold of visceral peritoneum connecting the sigmoid colon to the posterior abdominal wall
Where is the root of the signmoid mesocolon?
left iliac fossa
Where does the sigmoid mesocolon cross?
- bifurcation of the left common iliac vessels
- Left ureter
What does the sigmoid mesocolon transmit?
sigmoid branches of the inferior mesenteric vessels along with nerves and lymphatics
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sigmoid mesocolon
What is the function of the transverse mesocolon?
Suspends the transverse colon from the posterior abdominal wall
Where is the root of the transverse mesocolon?
Its root is just inferior to the pancreas
What is carried by the transverse mesocolon
branches of the middle colic vessels
What does the transverse mesocolon divide the peritoneal cavity (greater sac) into?
SUPRACOLIC & INFRACOLIC COMPARTMENTS
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transverse mesocolon
What does the supracolic compartment contain?
contains duodenum, liver, gallbladder, stomach & spleen
What does the infracolic compartment contain?
contains duodenum, jejunum, ileum, ascending & descending colon
What do peritoneal reflections create?
important recesses, spaces and gutters
Describe the communication between the supracolic and infracolic compartments?
free communication
What are paracolic gutters?
are grooves between the lateral aspect of the ascending or descending colon and the posterolateral abdominal wall
sites for collection and movement of peritoneal fluid
Give two alternatuve names for the hepatorenal recess
right posterior subhepatic space
Morison’s pouch
What is the hepatorenal recess?
Part of the peritoneal cavity on the right side between the liver and the right kidney and right suprarenal gland.
What is the hepatorenal recess continuous with anteriorly?
subphrenic
What are the deepest parts of the pelvic cavity?
Rectovesical and rectouterine pouches
What separates the rectum from the urinary bladder in males?
Rectovesical pouch
What separates tge rectum from the uterus in females?
Rectouterine pouch (of Douglas)
What separates the urinary bladder from the uterus in females?
Vesicouterine pouch
What is a peritoneal fold?
reflection of the peritoneum
What are peritoneal folds often formed by?
peritoneum that covers blood vessels, ducts or obliterated foetal vessels
What are the peritoneal folds on the posterior surface of the anterior abdominal walls
- The median umbilical fold is the remnant of the urachus that extends from the urinary bladder to the umbilicus
- The 2 medial umbilical folds overlie remnants of the umbilical arteries
- The 2 lateral umbilical folds are raised by the inferior epigastric arteries
What are peritoneal ligaments?
two-layered folds of peritoneum that connect 2 organs together
What are the 3 main recesses between the peritoneal folds?
- Supravesical fossa
- Medial umbilical fossa
- Lateral umbilical fossa
Describe the meaning of intraperitoneal
− almost totally covered with visceral peritoneum
− suspended by a mesentery
Describe the retroperitoneal
− lie behind or outside the peritoneum
− only partially covered with visceral peritoneum
Describe secondary retroperitoneal
− initially intraperitoneal but migrate retroperitoneally during embryogenesis & lose their mesentery
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red = retroperitoneal
yellow = intraperitoneal
organge = secondarily retroperitoneal
What are the primary retroperitoneal organs?
- Circulatory
- Abdominal aorta, Inferior vena cava
- Digestive
- Oesophagus (final part), Rectum (middle 1/3 with lower 1/3 totally
- Urinary
- Suprarenal (adrenal) glands, Kidneys, Ureters, Bladder
What are the secondary retroperitoneal organs?
- Pancreas (except its tail)
- Duodenum (except first part)
- Ascending and descending colon
Describe the parietal peritoneum nerve supply
- The peritoneum lining the anterior abdominal wall is supplied by the same nerves that supply the overlying skin − T7-L1
- Diaphragmatic peritoneum is supplied by the phrenic nerves − C3-5
- Pelvic parietal peritoneum is mainly supplied by the obturator nerves − L2-4
- The parietal peritoneum is sensitive to pain (well-localised), temperature, touch & pressure
Describe the visceral peritoneum nerve supply?
- It is supplied by autonomic afferent nerves that also supply the viscera
- The visceral peritoneum is sensitive only to stretch & tearing (which causes diffuse & poorly localised pain) but not to touch, pressure or temperature
- The brain cannot localise visceral pain & this is often referred to a dermatome