Gallbladder Physiology, Clinical disorders

Question 1

What increases bile secretion?

Answer 1

Vagal stimulation

HCl, digested proteins, fatty acids increase flow by stimulating secretin

Question 2

How does bile change while it is stored in the gallbladder?

Answer 2

It becomes more concentrated and more acidic

Question 3

What causes the gallbladder to fill?

Answer 3

Tonic contractions of the sphincter of Oddi create a pressure gradient that directs flow into gallbladder

Question 4

What causes the gallbladder to empty?

Answer 4

Coordinated gallbladder contraction, SO relaxation and meal intake – gallbladder empties 50-70% of contents within 30-40 minutes of eating

Question 5

What is the main stimuli for the gallbladder to empty?

Answer 5

Hormone cholecystokinin (CCK) released from duodenum in response to meals

Question 6

How is the gallbladder innervated?

Answer 6

Vagus/sympathetic braces that pass through celiac plexus
Preganglionic sympathetic level T8 and T9
Impulses from liver, gallbladder and bile ducts pass by means of sympathetic afferent fibers through splanchnic nerves – difficult to differentiate specific biliary tract site pain

Question 7

What are the two types of gallstones?

Answer 7

Cholesterol - Western countries

Pigment - Bilirubin deposition

Question 8

What else must occur, beside supersaturation with cholesterol, for stone formation?

Answer 8

Nucleation – protein secretion may be nucleating agent

Question 9

What are some risk factors for gallstones?

Answer 9

Increasing age
Female sex
Pregnancy 
Estrogen
Family history
Obesity 
Serum lipid levels
Rapid weight loss

Question 10

What is biliary sludge?

Answer 10

Calcium bilirubinate and cholesterol crystals embedded in mucus gel – possible precursor to stone formation

Associated with drugs like ceftriaxone, octreotide, thiazide diuretics, parenteral nutrition

Question 11

Inflammation of gallbladder causing a syndrome of prolonged (>4-6 hour) steady, right epigastric pain with fever, leukocytosis – associated with gallstone obstruction of the cystic duct

Answer 11

Acute Cholecystitis

Question 12

How does a patient with acute cholecystitis appear?

Answer 12

Ill, febrile, tachycardia, lies still – peritoneal inflammation (+ Murphy’s sign)

Question 13

What are some diagnostic studies used to diagnose cholecystitis?

Answer 13

Ultrasonography study

Cholescintigraphy

Question 14

Fever, jaundice and abdominal pain

Answer 14

Charcot’s Triad – Presentation of Acute Cholangitis (50-70%)

Question 15

Obstruction raises intrabiliary pressure, increases permeability of bile ducts, permits translocation of bacteria/toxins from portal circulation or ascending from duodenum

Answer 15

Acute Cholangitis

Question 16

What are the major bacterial pathogens associated with acute cholangitis?

Answer 16

Major gram negative: E. coli, Klebsiella, Enterobacteria

Major gram positive: Enterococcus

Question 17

What are some possible complications seen with acute cholangitis?

Answer 17

Confusion/hypotension with suppurative cholangitis

Septic shock/multi-organ failure

Question 18

What are some methods used to diagnose acute cholangitis?

Answer 18

Transabdominal ultrasonography: detects ductal dilation or stones; small calculi difficult
Magnetic resonance cholangiopancreatography: helps with small stones
ERCP (endoscopic retrograde cholangiopancreatograph) is useful for diagnosis and for drainage – especially if obstructive stone in distal CBD or ampulla leading to acute pancreatitis

Question 19

Clinically similar to acute cholecystitis but not associated with gallstones; usually in critically ill patients
High morbidity and mortality

Answer 19

Acalculous Cholecystitis

Question 20

Chronic progressive disorder or unknown etiology; characterized by inflammation, fibrosis, stricturing of medium/large ducts in intrahepatic/extra-hepatic biliary tree

Answer 20

Primary Sclerosing Cholangitis

Question 21

What is commonly seen in patients with PSC?

Answer 21

Ulcerative colitis (as high as 90%)

Question 22

How does gallbladder pain commonly present?

Answer 22

Mid epigastrium, dull pressure-like. Right shoulder/interscapular area. 
Restless 
Nausea, vomiting, diaphoresis 
Often unrelated to meal times
Nocturnal episodes are common 
Not chronic, continuous
Not associated with eliminations

Question 23

Group I

Answer 23

Typical biliary symptoms and gallstones

Rx = cholecystectomy

Question 24

Group II

Answer 24

Atypical symptoms and gallstones

Worrisome group – symptom persistence post-op, post-cholecystectomy syndrome in the making

Question 25

Group III

Answer 25

Gallstones without symptoms

Gallstones are present in approx 20% of US adults – No surgery

Question 26

Group IV

Answer 26

Typical symptoms without gallstones (functional disorder)
Rome III criteria for functional gallbladder disorder
Consider gall bladder ejection fraction (Biliary dyskinesia)
GBEF < 40% using continuous IV CCK infusion over 30 minutes – clinical action