Biliary tract: gallbladder and biliary disease Flashcards
Gallbadder function
The main function of the gallladder is to concentrate and store bile and delive it to the duodenum in response to meals
The gallbladder, bile ducts and sphincter of oddi act together to store/regulate flow of bile
gallbladder physiology
the human liver produces 1000mls of bile per day at rates that vary between .5 and 1 ml/min during fasting, and between 2 and 3 ml/min after feeding
Bile secretion increases with vagal stimulation, HCL, digested proteins, fatty acids increase flow by stimulating hormone SECRETIN
Bile secretion decreases with splanchnic stimulation
Fasting state- 80% bile stored in gallbladder, gallbladder mucosa greatest absorptive power per unit area of anny body structure, capacity 30-50 mls 300 mls when obstructed
bile acid metabolism
95% of bile acids are actively absorbed from terminal ileum, 5% in colon, bile acid hydrolysis/dehydrogenation performed by broad spectrum of anaerobic bacteria, hepatocyte reabsorbs BA from sinisodal blood carried thru to liver thru portal vein via a series of transporters
BAs aid in digestion/absorption of fat in the intestine
Gallstone formation
cholesterol gallstones- Balance between normal ratio of cholesterol to other biliary lipids is disrupted: cholesterol hypersecretion : hyposecretion BAs or phospholipids
Diminished bile acid pool of enterohepatic circulation interuppted
Supersaturation of cholesterol not sufficient for stone formation, nucleation must also occur, protein secretion may also be a nucleating agent
Gall bladder motility disorder with long residence times of bile in interprandial period
Cholelithiasis in pregnancy
incidence of biliary sludge (precursor to gall stones) and gallstones are30 and 12% during pregnancy and post partum
1-3% post partum woman: cholecystectomy within first year
Increased estrogen levels during pregnancy, super saturated bile/sluggish GB motility
Majority: sludge/gallstones DISSOLVE spontaneously after partitiion
biliary colic
Sludge or stones in the biliary duct causing pain, transient due to a fatty meal –> CCK–> gallbladder contraction
Kids, WBC are normal, do an ultrasound
episodic and self limited
Begins usually mid-epigastrium as dull, pressure like right shoulder off on
Unlike cardiac pain, the patient is restless, nausea and vomiting, diaphoresis
Mid age female
acute cholecystitis
Stone is impacted in the actual cystic duct–> Acute cholecystitis
Inflammation of the gallbladder causing a syndrome of prolonged steady right epigastric pain with fever, leukocutosis, associated with gallstone of the cytsic duct
Typicolly develops in pts with a history of symptomatic gallstones
Ductal obstruciton, ill appearing febrile tachycardic, lies still (parietal peritoneal inflammation, may have murphys sign, tender RUQ and timeline
LFT may be abnormal, need imaging vi ultrasound
Acute cholangitis
clinical syndrome featured by fever, jaundice and abdominal pain (Charcots Triad), results from stasis/ infection in biliary tract
Stone in the cystic duct compresses common bile duct–constant pain can’t get liver bile into intestine
Severity ranges from mild to life threatening
Obstruciton raises intrabiliary pressure, increases permeability of bile ductules, permits translocation of bacteria and toxins from portal circulation/ascending duodenum
Most common causes of biliary obstruction are CBD biliary calculi or benign stenosis
confusion/hypotension occur with suppurative cholangitis- septic shock/multi organ
Lab tests- elevated WBCs, cholestatic pattern of LFTs, Alk phos GGT and bili, blood cultures
Bacterial pathogens
GRAM NEGs: E coli, Klebsiella and enterobacter
GRAM POS- Enterococcus
Gallstone pancreatitis
obstructive stones in the distal common bile duct of ampulla of vater may cause acute pancreatitis
Endoscopic retrograde cholangiopantography (ERCP) may be necessary to extract and drain ducts in the case of concurrent cholangitis
Acalculous cholecystitis
Acute cholecystitis without gall stones, usually occurs in critically ill patients, accounts for 10% of acute cholecystitis, high morbitdidty and mortality
Commonly treated with percutaneous cholecystostomy tube
