GI: 340 - 342

Question 1

What are the three sites for anastomoses between the portal circulation and the systemic circulation?

Answer 1

1. Esophagus
2. Umbilicus
3. Rectum

Question 2

What are the two vessels that anastomose at the esophagus (for portal-systemic)?

Answer 2

Left gastric (portal) and esophageal (systemic)

Question 3

What are the two vessels that anastomose at the umbilicus (for portal-systemic)?

Answer 3

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

Question 4

What are the two vessels that anastomose at the rectum (for portal-systemic)?

Answer 4

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

Question 5

What are the clinical signs for portal hypertension?

Answer 5

Mnemonic: Gut, butt, and caput (medusae in the umbilicus)

1. Esophageal varices
2. Caput medusae
3. Anorectal varices (NOT internal hemorrhoids)

Question 6

How can we treat portal hypertension?

Answer 6

Transjugular intrahepatic portosystemic shunt (TIPS) between the portal vein and hepatic vein percutaneously relieves portal hypertension by shunting blood to the systemic circulation

Question 7

What is the pectinate line?

Answer 7

Formed where the endoderm (hindgut) meets the ectoderm

Question 8

What is another name for the pectinate line?

Answer 8

Dentate

Question 9

Where do internal vs. external hemorrhoids occur?

Answer 9

Internal hemorrhoids - above the pectinate line

External hemorrhoids - below the pectinate line

Question 10

Contrast the more likely cancers above vs. below the pectinate line.

Answer 10

Above - adenocarcinoma

Below - squamous cell carcinoma

Question 11

What is the arterial supply above the pectinate line?

Answer 11

Superior rectal artery (branch of the IMA)

Question 12

What is the venous drainage above the pectinate line?

Answer 12

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

Question 13

What is the lymphatic drainage above the pectinate line?

Answer 13

Deep nodes

Question 14

Are internal or external hemorrhoids more painful? Why?

Answer 14

Internal hemorrhoids - visceral innervation, NOT painful

External hemorrhoids - somatic innervation (inferior rectal branch of pudendal), painful

Question 15

Do anal fissures occur above or below the pectinate line?

Answer 15

Below

Question 16

What is the arterial supply below the pectinate line?

Answer 16

Inferior rectal artery (branch of internal pudendal artery)

Question 17

What is the venous drainage below the pectinate line?

Answer 17

Inferior rectal vein –> internal pudendal vein –> internal iliac vein –> IVC

Question 18

What is the lymphatic drainage below the pectinate line?

Answer 18

Superficial inguinal nodes

Question 19

What is an anal fissure?

Answer 19

Tear in the anal mucosa below the pectinate line

Question 20

Are anal fissures painful or painless?

Answer 20

Painful on defecation, bloody

Question 21

Why do anal fissures tend to be posterior?

Answer 21

Area is poorly perfused

Question 22

What are the three zones of the liver?

Answer 22

Zone I: periportal zone
Zone II: intermediate zone
Zone III: pericentral vein (centrilobular) zone

Question 23

Does the apical or basolateral side of hepatocytes face the bile canaliculi?

Answer 23

Apical

Question 24

What does the basolateral side of hepatocytes face?

Answer 24

Sinusoids

Question 25

Which zone of the liver is affected 1st by viral hepatitis?

Answer 25

Zone I

Question 26

Which zone of the liver is affected 1st by ischemia?

Answer 26

Zone III

Question 27

Which zone of the liver is associated with ingested toxins (e.g. cocaine)?

Answer 27

Zone I

Question 28

What important system does zone III of the liver contain?

Answer 28

Cytochrome P450

Question 29

What is zone III of the liver particularly sensitive to?

Answer 29

Metabolic toxins

Question 30

Where is the site of alcoholic hepatitis?

Answer 30

Zone III

Question 31

What comes together to form the common bile duct?

Answer 31

Common hepatic duct (composed of a right and left hepatic duct) and the cystic duct

Question 32

Where does the cystic duct originate?

Answer 32

Gall bladder

Question 33

What is the name of the opening where the common bile duct and the pancreatic duct meet?

Answer 33

Ampulla of Vater

Question 34

Tumors arising where in the pancreas can cause obstruction of the common bile duct?

Answer 34

Head of the pancreas (near the duodenum)

Question 35

What sphincter muscle is located at the base of the biliary tree and controls the bile/pancreatic enzymes that reach the duodenum?

Answer 35

Sphincter of Oddi

Question 36

How is the femoral region organized (lateral to medial)?

Answer 36

``` Mnemonic: NAVEL Nerve Artery Vein Empty space Lymphatics ```

Question 37

What is contained within the femoral triangle?

Answer 37

Femoral vein, artery, nerve

Question 38

What is the femoral sheath?

Answer 38

Fasical tube 3-4 cm below the inguinal ligament that contains the femoral vein, artery, and canal (deep inguinal lymph nodes)

Question 39

What structure is notably NOT contained in the femoral sheath?

Answer 39

Femoral nerve