Abdominal Organization: Part II

Question 1

peritoneum

Answer 1

serous membranes lining the internal surface of abdominoplevic cavity (parietal layer), and cover the viscera (visceral layer). they secrete serous fluid

Question 2

peritonealized organs

Answer 2

completely covered with visceral peritoneum, associated with a mesentery (ex. stomach, spleen, parts 1/4 of duodenum, jejunum, ileum, transverse and sigmoid colon)

Question 3

primary retroperitoneal organs

Answer 3

posterior to peritoneum; no mesentery (ex. kidneys, ureters, suprarenal glands)

Question 4

secondary retroperitoneal

Answer 4

during development the organ was peritonealized, but later in development the mesentery is pushed against the posterior body wall and fuses with surrounding parietal peritoneum (most of duodenum, ascending, descending colon, pancreas)
- secondary mesenteric attachment = fusion fascia

Question 5

peritonitis

Answer 5

inflammation of peritoneum. Parietal peritoneum is richly innervated by somatic nerves thus it is very painful and pain is well-localized. Innervation to the visceral peritoneum is autonomic, thus not well localized

Question 6

peritoneal adhesions

Answer 6

fusion of various parts of peritoneal membranes (due to inflammation, surgery, trauma, ulcers). can limit normal mvmt of viscera and cause chronic pain

Question 7

peritoneal dialysis

Answer 7

effective structure for blood dialysis

Question 8

dorsal mesentaries

Answer 8

originally suspends the entire abdominal gut tube to posterior body wall

• mesoesophagus
• greater omentum
• splenorenal ligmanet
• phrenicolic ligament
• mesentary proper
• mesoappendix
• transverse mesocolon
• sigmoid mesocolon

Question 9

greater omentum

Answer 9

gastrocolic + gastrosplenic + gastrophrenic ligaments

Question 10

lesser omentum

Answer 10

hepatogastric + hepatoduodenal ligmament

extends from liver to stomach/duodenum

Question 11

ventral mesentery

Answer 11

• lesser omentum
• falciform ligament
• coronary ligaments
• triangular ligaments

Question 12

peritonteal cavity divisions?

Answer 12

divided into greater and lesser sac (stomach is dividing line)
greater sac includes supracolic and infracolic compartments
infracolic compartment (rt/lt. paracolic gutter, rt/lt. infracolic space)

Question 13

lesser sac

Answer 13

posterior to stomach and lesser omentum
superior recess: bounded superiorly by diaphragm
inferior recess: between two layers of greater omentum

Question 14

greater sac:

Answer 14

contains supracolic, infracolic and paracolic gutters

Question 15

supracolic compartment (greater sac)

Answer 15

superior to transverse mesocolon

contains stomach, liver, spleen, gallbladder

Question 16

infracolic compartment (greater sac)

Answer 16

inferior to transverse mesocolon
contains small intestine, ascending colon, descending colon
seperated into right and left compartments by mesentary proper

Question 17

paracolic gutters (greater sac)

Answer 17

left and right

between posterolateral body wall and aschending/descending colon

Question 18

ascites

Answer 18

• excess fluid in the peritoneal cavity: can become purulent and lead to abscesses
• causes: cirrhosis with portal hypertension; kidney failiure; CHF; rutured ulcer; abdominal cancers; internal bleeding

Question 19

where will fluid collect?

Answer 19

absesses will often form in hepatorenal recess* and also in the subphrenic recess when patient is lying down

Question 20

how does fluid spread to pelvic cavity?

Answer 20

1. fluid from left infracolic compartment freely communicates with pelvic peritoneal cavity
2. fluid from right infracolic compartment is prevented from moving into pelvic cavity because of junction of the mesentery proper with cecum and ascending colon. Thus, fluid must first pass to the left infracoloic compartment before draining into the pelvic peritoneal cavity

Question 21

spread of fluid from paracolic gutters?

Answer 21

1. right paracolic gutter is open to hepatorenal and subphrenic recesses superiorly. fluid can pool in these spaces and cause abscesses which can dissect through the diaphragm into the thoracic cavity.
2. left paracolic gutter is closed superiorly by the phrenicolic ligament
3. fluid within both right and left paracolic gutters can drain into the pelvic peritoneal cavity

Question 22

foregut artery?

Answer 22

celiac trunk T12

Question 23

midgut artery?

Answer 23

superior mesenteric artery: L1

Question 24

hindgut artery?

Answer 24

inferior mesenteric artery: L3

Question 25

three aa. supplied by celiac trunk?

Answer 25

TV12: artery of the foregut that supplies distal esophagus to second portion of duodenum
- left gastric a, common hepatic a, splenic a.

Question 26

5 aa. supplied by superior mesenteric aa?

Answer 26

LV1: artery of the midgut: from 3rd part of duodenum to distal 2/3rd of transverse colon
Branches: 
inferior pancreaticoduodenal a. 
middle colic a. 
jejunal and ileal branches
right colic a. 
ileocolic

Question 27

3 aa. supplying inferior mesenteric a?

Answer 27

LV3: artery of hindgut

marginal a. left colic a. sigmoid aa. superior rectal a.

Question 28

hepatic portal vein

Answer 28

• abdominal viscera drains via vena comitantes to the hepatic portal vein
• all blood drained from gut goes to the liver first. the vein begins and ends in a capillary bed

Question 29

4 portal-caval anastamoses

Answer 29

• -> venous anastamoses between tributaries of portal vein and IVC: these contain no valves. they are important in cases of portal hypertension (due to liver cirrhosis), because blood flow will reverse through portal system and return to heart via the IVC or SVC, resulting in varicosities in the following regions:
  1. submucosa of inferior esophagus
  2. paraumbilical region
  3. submucosa of anal canal
  4. retroperitoneal

Question 30

esophageal varicies?

Answer 30

tributaries of SVC: esophageal vv.
tributaries of portal system: left gastric vv.
- results in dilated esophageal veins, bleeding from these varicosities can sometimes be severe and fatal

Question 31

caput medusa?

Answer 31

• dilated veins of the paraumbilical region
  tributaries of SVC/IVC: superior and inferior epigastric vv.
  tributaries of portal system: paraumbilical vv.

Question 32

hemorrhoids?

Answer 32

dilated veins of submucosa of anal canal due to portal hypertension
tributaries of IVC: middle and inferior rectal vv.
tributaries of portal system: superior rectal vv.

Question 33

dilated retroperitoneal vv? “cholic” veins

Answer 33

tributaries of IVC: gonadal and renal vv.

tributaries of portal system: ildeocolic, right, middle, left colic vv.