GI class 2 - dry lab

Question 1

the peritoneum is a transparent serous membrane that covers body wall and organs

although it is one continous layer, it is often described differently, depending on whether it lines the body wall or covers the organs

what are the 2 subdivisions?

it can also form folds, such as mesenteries and omenta, as well as ligaments, which may be vascular or avascular

Answer 1

parietal

visceral

Question 2

define the term peritoneal cavity?

Answer 2

the potential space between the parietal and visceral peritoneum

The peritoneal cavity is a true space between the parietal peritoneum (the peritoneum that surrounds the abdominal wall) and visceral peritoneum (the peritoneum that surrounds the internal organs)

Question 3

the 2 major divisions of the peritoneal cavity are termed sacs

which are these?

Answer 3

1. greater sac
2. lesser sac

Question 4

through which passage do the two sacs communicate?

Answer 4

epiploic foramen

Question 5

where is the epiploic foramen?

Answer 5

posterior to the free edge of the lesser omentum

Question 6

organs can be described depending upon how they are peritonised

organs completley surrounded by visceral peritoneum are _____________

or only covered on their anterior surface and therefore firmly attached to the posterior wall are ____________

Answer 6

intraperitoneal

retroperitoneal

Question 7

what are some retroperitoneal organs?

Answer 7

Main ones: ascending colon, descending colon, kidneys, pancreas

S = Suprarenal (adrenal) Glands

A = Aorta/IVC

D = Duodenum (except the proximal 2cm, the duodenal cap)

P = Pancreas (except the tail)

U = Ureters

C = Colon (ascending and descending parts)

K = Kidneys

E = (O)esophagus

R = Rectum

Question 8

what are some intraperitoneal organs?

Answer 8

main ones: stomach, liver, spleen, transverse colon

The intraperitoneal organs are the stomach, spleen, liver, bulb of the duodenum (1st part), jejunum, ileum, transverse colon, and sigmoid colon

Question 9

what is present in the peritoneal cavity?

Answer 9

peritoneal fluid (50ml)

Question 10

what is extraperitoneal?

Answer 10

the term extraperitoneal is used to describe the structures in the abdomino-pelvic cavity which are not covered in peritoneum

retroperitoneal structures may only be partially peritonised

Question 11

what layer of peritoneum is more sensitive to pressure, pain, heat and cold?

Answer 11

parietal peritoneum

has more somatic nerve innervation

Question 12

A

Answer 12

lesser omentum

Question 13

B

Answer 13

greater sac

Question 14

C

Answer 14

epiploic foramen

Question 15

D

Answer 15

lesser sac

Question 16

E

Answer 16

greater omentum

Question 17

what is the attachment of the greater omentum?

Answer 17

greater curvature of the stomach to posterior abdominal wall

Question 18

what is the attachment of the lesser omentum

Answer 18

liver to lesser curvature of the stomach and first part of the duodenum

Question 19

the greater omentum is often referred to by surgeons as the abdominal policemen, explain this

Answer 19

the lower margin and the left and right margins are free, and it moves about the abdominal cavity in response to peristaltic movements

in infection, especially appendicitis, inflammatory exudate causes the omentum to adhere to the site of infection, and wrap itself around the infected organ

this localises the infection to a small area of the cavity, protecting against serious diffuse peritonitis

Question 20

what is peritoneal pain?

Answer 20

pain form the partietal peritoneum lining the abdominal wall is innervated by the lower 6 thoracic nerves and L1, thus pain here is somatic and can be precisely localised. it is extremely sensitive to streching, made use of in clinical diagnosis - rebound tenderness

the visceral peritoneum is innervated by autonomic nerves. pain is often referred, and is dull and poorly localised. becuase the GI tract is a midline structure receiving bilateral nerve supply, pain is referred to the midline

Question 21

what are some wall msucles of the posterior abdominal wall?

Answer 21

psoas major

iliacus

quadratus lumborum

Question 22

what are some organs of the posterior abdominal wall

Answer 22

kidneys

ureter

supradrenal gland

Question 23

what are some main vessels of the posterior abdominal wall?

Answer 23

IVC

aorta

Question 24

what are some main nerves of the posterior abdominal wall?

Answer 24

femoral nerve

obturator

(2 main branches of the lumbar plexus)

Question 25

what are the 3 main openings in the diaphragm and what vertebral levels do they occur at?

Answer 25

caval hiatus - T8 oesophageal hiatus - T10 aortic hiatus - T12

Question 26

what are the 3 main branches of the abdominal aorta which supplies blood to the gut tube within the abdominopelvic cavity?

Answer 26

coeliac artery superior mesenteric artery inferior mesenteric artery

Question 27

at what vertebral level does the abdominal aorta divide into 2 common iliac arteries?

Answer 27

L4

Question 28

how is the IVC formed in the abdomen?

Answer 28

formed by the union of the right and left common iliac veins

Question 29

a

Answer 29

left gastric artery

Question 30

b

Answer 30

splenich artery

Question 31

c

Answer 31

proper hepatic artery

Question 32

d

Answer 32

superior mesenteric artery

Question 33

e

Answer 33

inferior mesenteric artery

Question 34

a

Answer 34

hepatic portal vein

Question 35

b

Answer 35

splenic vein

Question 36

c

Answer 36

superior mesenteric vein

Question 37

d

Answer 37

inferior mesenteric vein

Question 38

what 3 main branches supply the gut tube? and what levels do these 3 midline branches occur?

Answer 38

coeliac artery - T12 superior mesenteric artery - L1 inferior mesenteric artery - L3

Question 39

what are foregut strucutres?

Answer 39

abdominal part of oesophagus stomach proximal duodenum

Question 40

what are midgut structures?

Answer 40

distal duodenum jejunum ileum caecum ascending colon]proximal 2/3 of transverse colon

Question 41

what are hindgut strucutres?

Answer 41

distal 1/3 pf transverse colon descending colon sigmoid colon rectum

Question 42

artery supply foregut = artery supply midgut = artery supplying hindgut =

Answer 42

artery supply foregut = coeliac artery artery supply midgut = superior mesenteric artery artery supplying hindgut = inferior mesenteric artery

Question 43

name additional foregut and midgut-derived organs which are not part of the gut tube?

Answer 43

pancreas liver spleen gallbladder

Question 44

what is the venous drainage of the GI tract?

Answer 44

Question 45

blood from the abdominopelvic gastrointestinal tract drains via a portal system to the liver what is a portal system?

Answer 45

any system of blood vessels which has a capillary network at each end (the system of blood vessels consisting of the hepatic portal vein with its tributaries and branches)

Question 46

the portal vein is formed by the union of which 2 major veins of the abdominal cavity?

Answer 46

superior mesenteric vein splenic vein

Question 47

blood from the gut tube superior to the diaphragm and inferior to the pelvic floor drains via the systemic venous system. this means that an anastomosis is present at these watersheds: porto-systemic (portocaval anastomoses) list the 4 sites of portocaval anastomosis in the body?

Answer 47

in the distal oesophagus superior part of the rectum umbilicus area of the liver

Question 48

what is the clinical significance of these portocaval anastomoses?

Answer 48

in liver disease, e.g. hepatic cirrhosis, could cause back pressure leading to bleeding can go to systemic blood

Question 49

what is the sympathetic nerve supply to the abdominal viscera done by?

Answer 49

abdominopelvic splanchnic nerves (greater, lesser and least) prevertebral sympathetic ganglia abdominal aorta plexuses

Question 50

what is the parasympathetic nerve supply yo the abdominal viscera done by?

Answer 50

anterior and posterior vagal trunks (vagus nerve - 10th cranial nerve) pelvic splanchnic nerves (S2, S3 and S4)

Question 51

does parasympathetic and sympathetic innervation increase or decrease GI secretion?

Answer 51

parasympathetic - sympathetic -

Question 52

does parasympathetic and sympathetic innervation increase or decrease GI secretion?

Answer 52

parasympathetic - sympathetic -

Question 53

does parasympathetic and sympathetic innervation increase or decrease GI secretion?

Answer 53

parasympathetic - increases sympathetic - decreases

Question 54

does parasympathetic and sympathetic innervation increase or decrease peristalsis or GI motility?

Answer 54

parasympathetic - increases sympathetic - decreases

Question 55

what is the effect of parasympathetic and sympathetic innervation on blood vessels?

Answer 55

parasympathetic - little effect sympathetic - vasoconstriction

Question 56

what is the effect of vagotomy on gastric secretion? (a surgical operation in which one or more branches of the vagus nerve are cut, typically to reduce the rate of gastric secretion (e.g. in treating peptic ulcers))

Answer 56

reduces it

Question 57

what is the functional difference between the greater, lesser and least splanchnic nerves (splanchnic means viscera) and the pelvic splanchnic nerves?

Answer 57

greater, lesser and least are sympathetic pelvic are paradympathetic

Question 58

what is the chief difference in the arrangement of ganglia in the sympathetic and parasympathetic nervous system?

Answer 58

sympathetic goes into sympathetic trunk sympathetic is short pre-ganglionic and long post-ganglionic parasympathetic is long pre-ganglionic and short post-ganglionic different outflow regions

Question 59

study the following image

Answer 59

Question 60

although not part of the gastrointestinal system, we will consider these additional posterior abdominal wall organs what am i and where am i found?

Answer 60

the kidney posterior abdominal wall at the level of T12-L3

Question 61

the right kidney lies slightly at a lower level than the left kidney what is the reason for this?

Answer 61

due to the liver on the right side

Question 62

what are the 3 main structure entering or leaving the hilum of the kidney?

Answer 62

renal vein renal artery pelvis of the ureter

Question 63

what is the top one?

Answer 63

renal artery

Question 64

what is the middle one?

Answer 64

renal vein

Question 65

what is the bottom one?

Answer 65

pelvis of the ureter

Question 66

what is the anterior-to-posterior arrangement of the structures entering and leaving the hilum of the kidney?

Answer 66

renal vein - renal artery - ureter

Question 67

how are the kidneys peritonised?

Answer 67

retroperitoneal

Question 68

what is the anatomical location of the suprarenl gland, and what type of gland is it?

Answer 68

found above the kidneys and are endocrine glands

Question 69

what are ureters?

Answer 69

muscular ducts that carry urine from the kidneys to the urinary bladder

Question 70

what is the term used to describe the expanded upper part of the ureter?

Answer 70

renal pelvis

Question 71

the ureter is normally ocnstricted at 3 locations during its course from the kidneys to the urinary bladder, what are they?

Answer 71

1. at the junction of the ureters and renal pelvis (pelviiureteric junction) 2. as the ureters enter the pelvis and crosses over the common iliac artery bifurcation 3. at the vesicoureteric junction as the ureter obliquely enter the bladder wall (UVJ is the most distal portion of the ureter, at the point where it connects to the urinary bladder) From website: The ureter has a diameter of 3 mm 1 but there are three constrictions, which are the most common sites of renal calculus obstruction: at the pelviureteric junction (PUJ) of the renal pelvis and the ureter as the ureter enters the pelvis and crosses over the common iliac artery bifurcation at the vesicoureteric junction (VUJ) as the ureter obliquely enters the bladder wall

Question 72

are the ureters intraperiotoneal or retroperitoneal?

Answer 72

retroperitoneal