gross anatomy of GI system

Question 1

Viscera are classified as what?

Answer 1

peritoneal organs;

retroperitoneal organs

Question 2

define peritoneal organs

Answer 2

MOBILE organs w/ mesentery and almost completely enclosed in peritoneum

Question 3

define retroperitoneal organs

Answer 3

IMMOBILE organs that are partially covered w/ peritoneum

Question 4

name major peritoneal organs (suspended by mesentery)

Answer 4

stomach; liver & gallbladder;
spleen, tail of pancreas;
foregut duodenum, jejunum, ileum;
appendix, transverse colon

Question 5

name major secondary retroperitoneal organs (lost mesentery during development)

Answer 5

midgut duodenum;
head, neck, body of pancreas;
ascending, descending colon;
rectum

Question 6

name major primary retroperitoneal organs (never had mesentery)

Answer 6

kidneys, adrenal glands, ureter;
aorta, IVC;
lower rectum, anal canal

Question 7

if an occlusion of the celiac artery occurs at its origin of aorta, how will head of pancreas receive blood supply?

Answer 7

collateral circulation by anastomoses bw pancreaticoduodenal branches of both SMA and gasroduodenal arteries

Question 8

When are the branches of celiac circulation subject to erosion?

Answer 8

ulcer penetrating posterior wall of stomach or posterior wall of duodenum

Question 9

Which branch of celiac circulation are eroded by ulcer of posterior wall of stomach?

Answer 9

splenic artery

Question 10

Which branch of celiac circulation are eroded by ulcer of lesser curvature of stomach?

Answer 10

left gastric artery

Question 11

Which branch of celiac circulation are eroded by ulcer of posterior wall of 1st part of duodenum?

Answer 11

gastroduodenal artery

Question 12

patients w/ penetrating ulcer may have pain where?

Answer 12

referred pain in the shoulder

Question 13

how may ulcer pain cause referred pain in the shoulder?

Answer 13

air escapes through ulcer and stimulates peritoneum covering inferior aspect of diaphragm causing pain

Question 14

contents of penetrating ulcer of posterior wall of stomach or duodenum may enter where?

Answer 14

omental bursa

Question 15

hematemesis may result from what?

Answer 15

bleeding into lumen of esophagus, stomach, duodenum proximal to ligament of Treitz

Question 16

hematemesis commonly caused by what?

Answer 16

duodenal ulcer, gastric ulcer, esophageal varices

Question 17

Where are common sites of ischemic bowel infarction?

Answer 17

transverse colon near splenic flexure and in rectum

Question 18

infarction of transverse colon occurs where?

Answer 18

bw distal parts of middle colic branches of SMA and left colic branches of IMA

Question 19

infarction of rectum occurs where?

Answer 19

distal parts of superior rectal branches of iMA and middle rectal branches of internal iliac artery

Question 20

Patients w/ cirrhosis of liver may develop what?

Answer 20

portal HTN

Question 21

define portal HTN

Answer 21

venous blood from GI structures normally enters liver by way of portal vein=> forced to flow retrograde direction in tributaries of portal vein

Question 22

Retrograde blood flow from portal HTN leads to what?

Answer 22

forces portal venous blood into tributaries of SVC or IVC

Question 23

What forms to allow blood to bypass the liver?

Answer 23

portacaval anastomoses established at SVC or IVC=> umbilicus, rectum, esophagus, retroperitoneal organs

Question 24

What are the portal and caval anastomoses at the umbilicus?

Answer 24

portal=> paraumbilical veins;

caval=> superficial veins of anterior abdominal wall

Question 25

Clinical signs when umbilicus is site of anastomosis

Answer 25

caput medusa

Question 26

Clinical signs when rectum is site of anastomosis

Answer 26

internal hemorrhoids

Question 27

Clinical signs when esophagus is site of anastomosis

Answer 27

esophageal varices

Question 28

Clinical signs when retroperitoneal organs is site of anastomosis

Answer 28

not clinically relevant

Question 29

What are the portal and caval anastomoses at the rectum?

Answer 29

portal=>superior rectal veins (IMA);

caval=>middle and inferior rectal veins (internal iliac vein)

Question 30

What are the portal and caval anastomoses at the esophagus?

Answer 30

portal=> gastric veins

caval=> veins of lower esophagus=> drain azygos system

Question 31

What are the portal and caval anastomoses at the retroperitoneal organs?

Answer 31

portal=>tributaries of SMA and IMA

caval=> veins of posterior abdominal wall

Question 32

Where and how is IVC formed?

Answer 32

level of L5 vertebra by union of common iliac veins

Question 33

Is the IVC a midline structure?

Answer 33

no just right of midline

Question 34

What drains into the IVC on the right side of the body?

Answer 34

renal, adrenal and gonadal veins drain directly into IVC

Question 35

What drains into IVC on left side of body?

Answer 35

only left renal vein drains directly into IVC

Question 36

What drains into the left renal vein?

Answer 36

left gonadal and left adrenal veins

Question 37

How does the left renal vein get to the IVC?

Answer 37

crosses anterior aspect of aorta just inferior to origin of SMA

Question 38

How might there be a backup in the renal vein?

Answer 38

it being compressed by aneurysm of SMA as vein crosses anterior to aorta

Question 39

patients w/ compression of left renal vein may have what?

Answer 39

renal and adrenal HTN on the left and in males a varicocele on left