Flashcards in Abdomen I Deck (73)
Peritoneum and its Layers
Serous Membrane which forms the lining of the abdominal cavity
Composed of 2 layers:
-lines the anterior, posterior, lateral walls of the abdomen. The inferior surface of Diaphragm and the pelvic cavity.
-leaves the body wall to surround abdominal viscera. It is wrapped around the internal organs that are located inside the intraperitoneal space and is thinner than the parietal peritoneum.
What is between the parietal and visceral layers of the peritoneum?
The peritoneal cavity which is filled with serous fluid, to allow free movement of viscera
Subdivisions of the peritoneal cavity
-accounts for most of the space of the peritoneal cavity
-the first place you enter when you open the peritoneum
-a small space posterior to the lesser omentum, stomach, liver and inside the greater omentum.
-Continuous to the greater sac via the omental (epiploic) foramen
How do the greater and lesser sac of the peritoneal cavity communicate with each other?
Via the Epiploic foramen (Foramen of Winslow')
Difference between lesser sac of males and females
Males- closed cavity
Females- The fallopian tube opens through it into the peritoneal cavity
Double layer of peritoneum
During development the gut tube (Foregut- midgut and hindgut) invaginates into the peritoneal cavity and is suspended from the posterior abdominal wall by this dorsal mesentery.
Names of the peritoneal folds (based on location in GIT):
(a) Stomach- Omentum [lesser and greater]
(b) Small intestine- Mesentery
(c) Large Intestine- Meso-colon [mesoappendix, transverse mesocolon, sigmoid mesocolon]
(d) Abdominal Organs- Ligament [Falciform]
Freely mobile organs
These organs are completely covered by visceral peritoneum so are freely mobile.
-1st part of duodenum
The internal organs enclosed within the abdominal cavity
Organs which develop or come to lie upon the posterior abdominal wall, posterior to the visceral peritoneum.
Duodenum (2nd/3rd parts)
Double layer of peritoneum which connects an organ with another or anterior abdominal wall e.g. Falciform ligament
Double layer of peritoneum which results from the invagination of the peritoneum by the small intestine
Double layer of peritoneum passing from the stomach and first part of duodenum to adjacent organs.
-Greater omentum- greater curvature of stomach
-Lesser omentum- lesser curvature of stomach
Nerve supply to the peritoneum
- Somatic nerves of the overlying muscles and skin (ex. diaphragmatic peritoneum by phrenic N.)
- Autonomic nerves with the underlying viscera
What specific type of innervation does the Visceral peritoneum lack and what type does it have?
It doesn't have a somatic innervation (it is insensitive to pain) but it receive sympathetic innervation (sensitive to stretch, tension and ischemia).
Blood supply of the 3 parts of the gut tube
(1) Foregut- Celiac trunk (T12)
(2) Midgut- Superior mesenteric artery (L1)
(3) Hindgut- Inferior mesenteric artery (L3)
Commonalities shared by the blood supply of the gut tube
-All 3 arteries are single unpaired branches
-All 3 arteries arise from the anterior surface of the Abdominal Aorta
-All 3 branches anastomose with each other, providing alternative routes of arterial supply
Organs of the Foregut
1st half of duodenum
Organs of the Midgut
2nd half of duodenum
Two thirds of transverse colon
Organs of Hindgut
Left one third of transverse colon
Branches of the Celiac Trunk
Branches of the Superior Mesenteric Artery
Branches of the Inferior Mesenteric
Favorite number for the stomach
Rule of twos of the stomach
-2 borders with 2 omenta (greater & lesser)
-2 sacs (greater & lesser)
-2 surfaces (anterior & posterior)
-2 ends (cardiac & pyloric)
Divisions of the Stomach
Cardia, Fundus, Body, Pylorus (antrum, canal and sphincter)
Mucosa of stomach which is thrown into folds to allow for dilation of the stomach
Blood supply to stomach
What separates the structures of the stomach bed, from the stomach?