Peritoneum Flashcards
what is the peritoneum
transparent serous lining found in the abdominal cavity
what is the parietal peritoneum
lines the inner surface of the body wall
what is the visceral peritoneum
covers the surface of the organs
why does the peritoneum release a small amount of fluid
lubricate the internal surfaces of abdomen
when does the peritoneal cavity become obvious
usually filled with coils of intestine - potential space - becomes obvious in disease or trauma when cavity fills with blood or fluid
what is the mesentry
double fold of peritoneum that encloses organ and connects it to body wall - intestine
why does the small intestine have a mesentry
movement of intestine is important during peristalsis
- mesentry provides support, permits movement and also allows passage of blood vessels to and from intestine
describe the movement of peritoneal fluid in the abdomen
moves up towards the diaphragm and is absorbed into venous system by small veins around diaphragm
what are the spaces either side of the large intestine called
right and left paracolic gutter
what type of nerves supply the parietal peritoneum
somatic nerves (final layer of abdominal wall)
the parietal peritoneum is supplied by somatic nerves - what does this mean re pain sensation
localise pain in same way as structures of abdominal wall
the parietal peritoneum is sensitive to
pain, touch, temperature and pressure
what nerves supply the lateral and anterior parietal peritoneum
lower 6 thoracic nerves
what nerves supply the central part of parietal peritoneum at diaphragm
phrenic nerves
what nerves supply the pelvic parietal peritoneum
obturator nerve
what kind of nerves supply the visceral peritoneum
visceral peritoneum shares the autonomic nerve fibres from the organs it covers
what is the visceral peritoneum sensitive to
stretch via ANS afferent fibres
give 2 examples of stretch that visceral peritoneum would be sensitive to
over-distension
mesenteries of small and large intestine sensitive to mechanical stretching
visceral peritoneum will refer pain to
body wall
the peritoneum has a large store of what
fat
give 3 fat stores in peritoneum
omenta
mesentery
appendices epiplocae
define intra-peritoneal
completely surrounded by mesentery except at their point of attachment - accommodates some movement needed by the organ e.g. small intestine
intraperitoneal organs
stomach
gall bladder
small intestine (only 1st part of duodenum)
spleen
liver
caecum (some appendix)
transverse and sigmoid colon
define extraperitoneal
no mesentery ever or lost in development
define retroperitoneal
structures that are partially covered by peritoneum and are held against body wall
define primary retroperitoneal
formed on the body wall and have been covered by peritoneum
give an example of a primary retroperitoneal organ
kidneys
suprarenal glands
define secondary retroperitoneal
moved position during development to lie against body wall
give an example of secondary retroperitoneal organ
ascending and descending colon
2nd, 3rd and 4th parts of duodenum
pancreas
upper 2/3 rectum
define infra-peritoneal and give examples
sub-peritoneal
lower 1/3 rectum and many pelvic organs
does the parietal peritoneum extend into the pelvic cavity
yes - abdominal and pelvic cavities are continuous so parietal peritoneum extends into pelvis to cover pelvic organs - sub or infra-peritoneal
how is the peritoneum arranged in the abdominal cavity
greater and lesser sac
what does the greater sac hold
intestines
what is the greater omentum
long strip of peritoneum passing anterior to the intestines close to the body wall - helps to divide greater and lesser sac
what is the first structure seen one abdominal wall has been reflected
greater omentum
where is the greater omentum suspended from
greater curvature of stomach
the greater omentum overlies the
transverse colon
what does the greater omentum contain
blood vessels
nerves
lymphatics
fatty tissue
why is the greater omentum known as the policeman of the abdomen
the GO moves with the small intestine during peristalsis - if there is a problem with part of the intestine (infected or damaged) it will move less allowing the healthy, more mobile intestine to push the GO over the unhealthy intestine so GO is found in areas where there is a problem with the intestine
what happens if the GO stays over the unhealthy tissue for some time
it will form connective tissue adhesions that will help to localise infection within abdominal cavity and slow spread of problem
how many layers is the GO
as it passes from greater curvature of stomach it is a double layer - it meets and fuses with another double layer that has passed over the transverse colon creating a 4 layered structure
what part of the abdominal cavity does the GO close off posterior to the stomach
lesser sac
the transverse colon divides the peritoneal cavity into what
supra-colic compartment and infra-colic compartment
what organs are found in the supracolic compartment of the abdomen
(most of foregut)
liver
gall bladder
stomach
what organs are found in the infracolic compartment of the abdomen
(midgut) intestines
and infracolic
the greater omentum carries the blood vessels to supply what
greater curvature of stomach and itself
what vessels does the greater omentum carry
left and right gastro-omental arteries, veins and lymphatics
what is another name for the gastro-omental vessels
gastro-epiploic vessels
what is another name for the lesser sac
omental bursa
what is the lesser sac
space posterior to the stomach and lesser omentum
where does the lesser omentum lie
between the liver and the lesser curvature of the stomach
how many layers is the lesser omentum
double layer of peritoneum
what forms the anterior wall of the lesser sac
lesser omentum
the lesser omentum lies anterior to the opening to the greater sac - what is this called
epiploic foramen
what closes the lesser sac at the lateral side
gastrosplenic ligament (between the stomach and the spleen)
and the lienorenal ligament (between spleen and left kidney)
what does the free edge of the lesser omentum that lies anterior to the epiploic foramen carry
hepatic artery, bile duct and hepatic portal vein
where abouts are the structures carried by the free edge of the lesser omentum
hepatic artery - on left
bile duct - on right
^^ both anterior)
hepatic portal vein (posterior)
what is the epiploic (omental) foramen
an area of communication between the greater and lesser sac
what is the epiploic foramen
gap between the free edge of the lesser omentum and the body wall
what forms the posterior boundary of the epiploic foramen
IVC
what forms the superior boundary of the epiploic foramen
liver
what forms the anterior boundary of the epiploic foramen
lesser omentum
what is a mesentery
double layer of peritoneum connecting to an organ
how do you know if someone is talking about the mesentery connected to the small intestine
it is the mesentery proper or ‘the’ mesentery
what vessels does the mesentery enclose
jejunal and ileal branches of the superior mesenteric vessels
what is the function of the mesentery
connects the small intestine to the body wall and allows mobility of the intestines in the peritoneal cavity
the mesentery carries what to/from where
carries vessels, nerves and lymphatics to/from most of the small intestine (jejunum and ileum)
what are mesocolons
folds of peritoneum that are attached to structures of the large intestine
what do mesocolons carry
blood vessels, nerves and lymphatics
what structures might you see in the DR when you remove the parietal peritoneum from the posterior abdominal wall
IVC
aorta
lumbar plexus
kidney (has a peri-renal fat pad)
