Biliary Tract Flashcards
Which is the proximal and which is the distal bile duct?
Proximal is close to the liver
What is the name of the node in Calot’s triangle?
Calot’s node
What are the small ducts that drain bile directly into the gallbladder from the liver?
Ducts of Luschka
Which artery is susceptible to injury during cholecystectomy?
Right hepatic artery, because of its proximity to the cystic artery and Calot’s triangle
What is the name of the valves of the gallbladder?
Spiral valves of Heister
Where is the infundibulum of the gallbladder?
Near the cystic duct
Where is the fundus of the gallbladder?
At the end of the gallbladder
What is Hartmann’s pouch?
Gallbladder infundibulum
What are the boundaries of the triangle of Calot?
- Cystic duct
- Common hepatic duct
- Cystic artery
What is the source of alkaline phosphatase?
Bile duct epithelium
What is in bile?
Cholesterol, lecithin (phospholipid), bile acids, bilirubin
What does bile do?
Emulsifies fats
What is the enterohepatic circulation?
Circulation of bile acids from liver to gut and back to the liver
Where are most of the bile acids absorbed?
In the terminal ileum
What stimulates gallbladder emptying?
Cholecystokinin and vagal input
What is the source of cholecystokinin?
Duodenal mucosal cells
What stimulates the release of cholecystokinin?
Fat, protein, amino acids, and HCl in the duodenal lumen
What inhibits the release of cholecystokinin?
Trypsin and chymotrypsin
What are the actions of cholecystokinin?
- Gallbladder emptying
- Opening of the ampulla of Vater
- Slowing of gastric emptying
- Pancreas acinar cell growth and release of exocrine products
At what level of serum total bilirubin does one start to get jaundiced?
> 2.5
Classically, what is thought to be the anatomic location where one first finds evidence of jaundice?
Under the tongue
With good renal function, how high can the serum total bilirubin go?
Very rarely, > 20
What are the signs and symptoms of obstructive jaundice?
Jaundice, dark urine, clay-colored stools (acholic stools), pruritus, anorexia, nausea
What causes the itching in obstructive jaundice?
Bile salts in the dermis (not bilirubin)
What is cholelithiasis?
Gallstones in the gallbladder
What is choledocholithiasis?
Gallstone in the common bile duct
What is cholecystitis?
Inflammation of the gallbladder
What is cholangitis?
Bacterial infection of the biliary tract from obstruction
What is cholangiocarcinoma?
Malignancy of the extra-hepatic or intra-hepatic ducts
What is Klatskin’s tumor?
Cholangiocarcinoma of bile ducts at the junction of the right and left hepatic ducts
What is biliary colic?
Pain from gallstones, usually from a stone in the cystic duct.
Pain is located in the RUQ, epigastrium, or right subscapular region of the back.
It usually lasts minutes to hours but eventually goes away.
Often postprandial, especially fatty foods.
What is the differential diagnosis of distal bile duct obstruction?
Choledocholithiasis, pancreatic carcinoma, pancreatitis, ampullary carcinoma, LAD, pseudocyst, post-surgical stricture, ampulla of Vater dysfunction, lymphoma, benign bile duct tumor, parasites
What is the initial study of choice for obstructive jaundice?
U/S
What lab results are associated with obstructive jaundice?
Elevated alkaline phosphatase, bilirubin +/- LFTs
What is the incidence of cholelithiasis?
10% of the US population
What are the big 4 risk factors for cholelithiasis?
Female, Fat, Forty, Fertile (multiparity)
What are the types of gallstones?
- Cholesterol
2. Pigment
What are the types of pigmented gallstones?
- Black (calcium bilirubinate)
2. Brown (biliary tract infection)
What are the causes of black-pigmented gallstones?
Cirrhosis, hemolysis
What is the pathogenesis of cholesterol stones?
Secretion of bile supersaturated with cholesterol (decreased lecithin, bile salts); Cholesterol precipitates out and forms solid crystals, then gallstones
Is hypercholesterolemia a risk factor for gallstone formation?
No (but hyperlipidemia is)
What are the signs and symptoms of cholelithiasis?
Symptoms of : biliary colic, cholangitis, choledocholithiasis, pancreatitis
Is biliary colic pain really “colic”?
No, symptoms usually last for hours
What percentage of patients with gallstones are asymptomatic?
80%
What is thought to cause biliary colic?
Gallbladder contraction against a stone temporarily at the gallbladder/cystic duct junction, in the cystic duct, or passing through the cystic duct
What is Boas’ sign?
Referred right subscapular pain of biliary colic
What the 5 major complications of gallstones?
- Acute cholecystitis
- Choledocholithiasis
- Gallstone pancreatitis
- Gallstone ileus
- Cholangitis
How is cholelithiasis diagnosed?
H&P, U/S
How often does U/S detect cholelithiasis?
98% of the time
How often does U/S detect choledocholithiasis?
33% of the time
How are symptomatic or complicated cases of cholelithiasis treated?
Cholecystectomy
What are the possible complications of a lap chole?
Common bile duct injury, right hepatic duct or artery injury, cystic duct leak, biloma