Hepatic, Biliary and Pancreatic Anatomy

Question 1

1. Describe the location of the liver in the abdominal cavity:
2. How much the liver weigh in males and females?

Answer 1

1. Location of Liver:
   
   • 5th intercostal space to the subcostal margin (12-15 cm) from sup. to inf.
   • 15 - 18 cm right to left
2. Weight
   
   • Male: 1.8 kg
   • Female: 1.4 kg

Question 2

1. How is blood supplied to the liver?
2. What empties into the 2nd part of the duodenum?

Answer 2

1. Dual blood supply:
   
   • Portal vein: carries 70% of the total blood into the liver
   • Hepatic artery: carries 30% of total blood into the liver (more oxygenated)
2. Common bile duct + pancreatic duct empty into the duodenum (2nd part)

Question 3

1. Which ligament of the liver separates the left and right lobes anteriorly?
2. What ligament is the obliterated umbilical vein?

Answer 3

1. falciform ligament
2. round ligament

Question 4

1. What is the porta hepatis?
   
   • What three structures are found here?
2. What do impressions of the liver tell us?
3. Where does the diaphragm attach directly to the liver?

Answer 4

1. Porta hepatis = entrance into the liver
   
   • Portal vein
   • Hepatic artery
   • Common bile duct
2. Impressions tell us that the liver is in close proximity to other organs
3. Bare area = site where diaphragm directly attaches

Question 5

• How are the hepatic segments drained?
  
  • How does this affect liver donations?
• What is different about the caudate lobe?

Answer 5

• Left hepatic vein drains segments 2, 3, 4 (left lobe)
  
  • donate segments 2 & 3 to peds (less mass needed)
• Right hepatic vein drains segments 5, 6, 7, 8 (right lobe)
  
  • donate segments 5-8 to adults (more mass needed)
• Caudate lobe (seg 1) receives blood supply and bile bilaterally and drains directly into the hepatic vein

Question 6

What controls the amount of bile and pancreatic enzymes released into the duodenum?

Answer 6

Sphincter of Oddi

Question 7

Why is the pancreas usually protected in anterior trauma event?

Answer 7

the pancreas is retroperitoneal

Question 8

Decsribe the path of the bile ducts (liver to duodenum)

Answer 8

1. right + left hepatic ducts ⇒ common hepatic duct
2. common hepatic duct + cystic duct ⇒ common bile duct
3. common bile duct and main pancreatic duct empty into the duodenum

Question 9

1. How will portal vein obstruction affect the liver?
2. What drains the midgut?
3. What drains the hingut?

Answer 9

1. Portal vein obstruction will not have a huge effect because the liver has dual blood supply
2. Midgut ⇒ superior mesenteric vein
3. Hindgut ⇒ inferior mesenteric vein

Question 10

Where does the common hepatic artery branch from?

Answer 10

abdominal aorta

Question 11

Where does hepatic vein drain?

Answer 11

inferior vena cava

Question 12

Describe the structure of the classic lobule:

Answer 12

1. Portal Triad
2. Central vein
3. Sinusoids
   
   • ​​drain into central vein
   • lined by Kuppfer cells
4. Bile canaliculi
   
   • drain bile ducts
5. Space of Disse
   
   • ​​drain lymph ducts
   • contain Stellate cells
6. Liver cell plate
   
   • ​​contain hepatocytes

Question 13

1. What are Kuppfer cells?
2. What are Stellate cells?

Answer 13

1. Kuppfer cells = liver macrophages
2. Stellate cells = deposit reticular substance (type III collagen)
   
   • involved in fibrosis

Question 14

How can the functional liver be described? (3)

Answer 14

1. Classic lobule
2. Portal lobule
3. Liver acinus

Question 15

How is the gallbladder involved in bile?

Answer 15

• Mechanism for concentration:
  
  • absorption of water, sodium and chloride leads to concentration of bile salts, cholesterol, lecithin and bilirubin
• Cholesterol and lecithin are solubilized by bile salts
• Volume goes from 500 ml to 50 ml

Question 16

• What is the function of bile salts?
• What is the function of micelles?

Answer 16

• Emulsification: decreases surface tension and breaks fat globules into smaller size particles
• Forms micelles (soluble in chyme) and helps absorption of fat breakdown products
  
  • Prevents fat molecules from re-forming
  • Fatty acids, monoglycerides, cholesterol

Question 17

How do the following affect the liver:

• **Cholecystokinin (CCK) **
• Secretin

Answer 17

• Cholecystokinin (CCK)
  
  • Fatty foods in duodenum results in release of CCK
  • CCK results in:
    
    • gallbladder contraction and emptying in under 1 hour
      
      • Acetylcholine from vagus is weaker stimulus
    • relaxation of the Sphincter of Oddi
• Secretin
  
  • Acts on biliary epithelium to produce a solution rich in sodium bicarbonate
    
    • Helps neutralize acids
    • Optimizes pancreatic function

Question 18

Pancreatic secretions in response to chyme in upper small intestine with juice characteristics depend on ….

Answer 18

type of food

Question 19

What is the difference between the pancreatic acini and pancreatic ducts?

Answer 19

• Acini secrete digestive enzymes
• Ducts secrete a bicarbonate-rich solution

Question 20

What does the pancreas secrete for protein digestion?

Answer 20

• TRYPSIN, chymotrypsin and carboxypolypeptidase
  
  • Secreted in inactive form:
    
    • chymotrypsin, chymotrypsinogen and procarboxypolypeptidase
• Trypsin further activates trypsinogen as well as converting chymotrypsinogen to chymotrypsin and procarboxypeptidase to carboxypeptidase

Question 21

What is the function of trypsin inhibitor?

Answer 21

• Trypsin inhibitor prevents activation until secretions reach small intestine
  
  • pancreatitis wil develop if pancreatic enzymes are activated in the pancreas

Question 22

What is the pancreatic enzyme for carbohydrate metabolism?

Answer 22

pancreatic amylase

Question 23

What is pancreatic enzyme for fat digestion?

Answer 23

• Pancreatic lipase digests all TG it can reach within 1 minute
  
  • Free fatty acids and 2-monoglycerides
  • bile salts form micelles and remove monoglycerides and fatty acids and transport them to brush border for absorption

Question 24

What do the pancreatic ductules and ducts secrete to control pH?

Answer 24

sodium bicarbonate

Question 25

How do the following affect the pancreas:

• Cholecystokinin
• Secretin

Answer 25

• Cholecystokinin: acts on acini to produce digestive enzymes
• Secretin: acts on pancreatic duct epithelium to produce bicarbonate-rich solution