Blood supply of the GI system

Question 1

At what level is the celiac trunk?

Answer 1

T12

Question 2

At what level is the SMA?

Answer 2

L1

Question 3

What branches laterally at the same level as the celiac trunk?

Answer 3

Inferior phrenic arteries

Question 4

What branches laterally at the same level as the SMA?

Answer 4

Renal arteries

Question 5

At what level does the IMA leave the aorta?

Answer 5

L3

Question 6

What branches off between the SMA and IMA?

Answer 6

Gonadal arteries

Question 7

At what level is the bifurcation of the aorta?

Answer 7

L4

Question 8

What is the portosystemic anastomosis of the esophagus?

Answer 8

Left gastric (portal) to esophageal (system)

Question 9

What is the clinical manifestation of esophageal anastomosis?

Answer 9

Esophageal varices

Question 10

What is the portosystemic anastomosis of the umbilicus?

Answer 10

Paraumbilical (portal) to small epigastric veins of the anterior abdominal wall (systemic)

Question 11

What is the clinical manifestation of umbilical antastomosis?

Answer 11

caput medusae

Question 12

What is the portosystemic anastomosis of the rectum?

Answer 12

Superior rectal (portal) to middle and inferior rectal (systemic)

Question 13

What is the clinical sign of rectal portosystemic anastomosis?

Answer 13

Anorectal varices (not the same as internal hemorrhoids!)

Question 14

Where is the pectinate line of the anal canal?

Answer 14

Between promixal 1/3 and distal 2/3

Question 15

What is the pectinate/dentate line the meeting place of?

Answer 15

Where endoderm (hindgut) meets ectoderm

Question 16

What kind of hemorrhoid presents above the pectinate line?

Answer 16

Internal hemorrhoids.

Question 17

Are internal hemorrhoids painful or painless?

Answer 17

Painless. Visceral innvervation.

Question 18

What is the blood supply above the pectinate line?

Answer 18

Superior rectal artery (branch of IMA)

Question 19

What is the venous drainage above the pectinate line?

Answer 19

Superior rectal vein –> inferior mesenteric vein –> portal system

Question 20

What is the lymphatic drainage above the pectinate line?

Answer 20

Internal iliac lymph nodes

Question 21

What kind of cancer presents above the pectinate line?

Answer 21

Adenocarcinoma.

Question 22

What are the sources of bleeding that present below the pectinate line?

Answer 22

External hemorrhoids and anal fissures

Question 23

What is an anal fissure?

Answer 23

Tear in the anal mucosa below the pectinate line. Presents with Pain while Pooping w/ blood on toilet Paper. Located posteriorly since this area is poorly perfused.

Question 24

What kind of cancer presents below the pectinate line?

Answer 24

Squamous cell carcinoma.

Question 25

What is the blood supply below the pectinate line?

Answer 25

Inferior rectal artery (branch of internal pudendal artery)

Question 26

What is the venous drainage below the pectinate line?

Answer 26

Inferior rectal vein --> internal pudendal vein --> internal iliac vein --> common iliac --> IVC

Question 27

What does the apical surface of hepatocytes face?

Answer 27

Bile caniculi

Question 28

What does the basolateral surface of hepatocytes face?

Answer 28

Sinusoids

Question 29

What is Zone I of the hepatic lobule?

Answer 29

Periportal zone - where blood arrives from intestine via portal vein, and from heart via hepatic artery.

Question 30

What is Zone II of the hepatic lobule?

Answer 30

intermediate zone

Question 31

What is Zone III of the hepatic lobule?

Answer 31

Pericentral vein/centrilobular zone. Central vein is tributary of hepatic vein.

Question 32

Which zone of the hepatocyte is first affected by viral hepatitis?

Answer 32

Zone I

Question 33

Which zone of the hepatocyte is first affected by ingested toxins such as cocaine?

Answer 33

Zone I

Question 34

Which zone of the hepatocyte is first affected by yellow fever?

Answer 34

Zone II

Question 35

Which zone of the hepatocyte is first affected by ischemia?

Answer 35

Zone III

Question 36

Which zone of the hepatocyte contains cytochrome p450 system?

Answer 36

Zone III

Question 37

Which zone of the hepatocyte is most sensitive to metabolic toxins?

Answer 37

Zone III

Question 38

Which zone of the hepatocyte is the site of alcoholic hepatitis?

Answer 38

Zone III

Question 39

In what direction does blood flow in the hepatocyte?

Answer 39

Zone I --> Zone III

Question 40

In what direction does bile flow in the hepatocyte?

Answer 40

Zone III --> Zone I

Question 41

What is the space of disse?

Answer 41

lymphatic drainage of hepatocyte

Question 42

What causes cholangitis and pancreatitis at the same time?

Answer 42

Gallstone at the ampulla of Vater

Question 43

What is the ampulla of Vater?

Answer 43

Confluence of common bile duct and pancreatic duct.

Question 44

Where is the sphincter of oddi?

Answer 44

At the ampulla of vater

Question 45

What do tumors that arise in the head of the pancreas cause?

Answer 45

Obstruction of common bile duct only; painless jaundice.