Medbear Gall Bladder Flashcards
Describe the anatomy of the gall bladder based on the following:
Anatomical areas
Location
Duct
- Gall bladder is divided into 4 anatomical areas: Fundus, Body, Infundibulum and Neck
- It is a pear-shaped sac
- Lies beneath segment 4 and 5
- Lined by SIMPLE COLUMNAR EPITHELIUM (It lacks muscularis mucosa and submucosa)
- Surface is covered by peritoneal serosa
It consists of
1. Common Hepatic Duct (~4cm) -> fusion of right and left hepatic duct
2. Cystic Duct (~4cm) - variation exists
3. Common Bile Duct (~10cm) -> no distinct muscle layer (So, no peristalsis)
State the boundaries for triangle of Calot
Lateral = Cystic duct
Medial = Common bile duct
Superior = Liver
Explain bilirubin metabolism
In complete biliary obstruction or severe intrahepatic cholestasis -> conjugated bilirubin leaks out and appears in urine -> Giving tea-colored urine and clay-colored stool (due to lack of formation of UROBILINOGEN)
State the composition of bile
- Water
- Phospholipids, electrolytes
- Bile salts - cholic acid, chenodeoxycholic acid
- Bile pigments - conjugated bilirubin
State the (4) functions of the gall bladder
- Reservoir for bile
- Concentration of bile -> active absorption of water, NaCl and HCO3 by mucus membrane of the gall bladder -> prevent gall bladder from being distended
- Secretion of mucus
- Gall bladder contraction stimulated by cholecystokinin (CCK), mediated by CHOLINERGIC VAGAL NEURONS
CCK half life = 2-3 minutes
Increase bile excretion - CKK, secretin, vagal input
Decrease bile excretion - somatostatin, sympathetic stimulation
Bile is normally neutral pH (But, increase in protein shifts bile to become acidic)
Define jaundice
- It is defined as yellow pigmentation of the skin and eyes due to excess bilirubin in the circulation
- Clinically detected if serum bilirubin levels >40 micromol/L
State Courvoisier’s law
In patients with a palpable enlarged gall bladder and painless jaundice, the cause is unlikely to be stone - malignancy until proven otherwise
What are the (5) exception that Courvoisier’s law doesn’t apply?
- Mirizzi’s syndrome - stones in the Hartmann’s pouch
- Double impaction - stones occluding cystic duct and distal CBD
- Oriental cholangiohepatitis - ductal stones form secondary to liver fluke infestation
- Congenital choledochal cyst
- Common hepatic duct obstruction
State the cause of obstructive jaundice based on the following:
Commonest cause
Painful obstructive jaundice
Painless obstructive jaundice
Commonest causes = gallstones, tumour, hepatitis
Painful obstructive jaundice = choledocolithiasis (+/- cholangitis), strictures, hepatic cause
Painless obstructive jaundice = PERIAMPULLARY TUMOUR
Give 3 differentials for post-operative jaundice
- Retained CBD stones
- Post-op biliary leak
- Injury to CBD +/- stricture formation
Define cholelithiasis
Refers to the presence of stone in the gall bladder
List the types of stones present in cholelithiasis with its corresponding incidence
- Cholesterol stone (85%)
- Pigment stone (15%)
- Black (sterile) gall stones -> Hard
- Brown (infected) gall stones -> Soft
- Mixed
- Biliary sludge
Describe on cholesterol gallstones based on the following
1. Radiolucent or radio-opaque
2. Risk factors
3. Pathophysiology
- Radiolucent
- Associated with 4F (Fat, Female, Forty, Fertile - estrogenic influence)
Pathophysiology:
- Increased cholesterol secretion in bile
- Decreased emptying of the gallbladder
Describe on black (sterile) gallstones based on the following:
1. Radiolucent or radio-opaque
2. Composed of
3. Pathophysiology
- Radio-opaque
- Composed of calcium salts (hard, speculated and brittle)
Pathophysiology:
- Increased secretion of bilirubin conjugates into bile
- Gallbladder hypomotility
- Decreased bilirubin solubilizes and bile stasis
Describe on brown (infected) gallstones based on the following:
1. Radiolucent or Radio-opaque
2. Composed of
3. Pathophysiology
- Radio-opaque -> formed in intra and extra-hepatic duct
- Composed of calcium salts and bacterial cell bodies
Pathophysiology:
- Infection - Enteric bacteria (E.coli, Klebsiella)
- Biliary stasis
What is biliary sludge?
- Microlithiasis suspended in bile
- Can be visualized on US scan
- Sludge is a pre-stone condition
20% of biliary sludge will disappear
Describe the biliary colic symptoms of cholelithiasis using SOCRATES
Site = Epigastric (70%) or RHC pain
Onset = usually occurs within hours of eating a meal
Character = waxing and waning character
Radiation = inferior angle of scapula or tip of right shoulder
Timing = distinct attack lasting 30 minutes to several hours
Associated symptoms =
- Patient gets better after vomiting
- Bloating, abdominal distension
- Back pain, LUQ pain
List the complicated conditions of cholelithiasis (In the gallbladder)
- Hydrops of gall bladder
- Acute calculous cholecystitis -> acute gangrenous cholecystitis / empyema of the gallbladder
- Porcelain gallbladder / chronic cholecystitis -> Increase risk of gall bladder cancer
- Gallbladder cancer
- Mirizzi’s syndrome
List the complicated conditions of cholelithiasis (In the common bile duct)
CHOLEDOCHOLITHIASIS leading to
- Obstructive jaundice
- Ascending cholangitis
- Secondary biliary cirrhosis
- Gallstone pancreatitis
List the complicated conditions of cholelithiasis (In the gut)
- Cholecystoenteric fistula formation -> Intestinal obstruction/gallstone ileus
- BOUVERET SYNDROME -> GOO (rare)
- Gallstone dyspepsia (non-ulcer dyspepsia) - fatty food intolerance, dyspepsia, flatulence