Chapter 32 - Biliary System Flashcards
1
Q
What is the triangle of Calot?
A
Cystic duct, common hepatic duct, cystic artery.
This is now cystic duct, common hepatic duct, and inferior edge of the liver.
2
Q
What blood vessels supply the hepatic and CBD?
A
Right hepatic and retroduodenal branches of the GDA
3
Q
What side of the CBD are the lymphatics on?
A
Right
4
Q
What type of cells makes up the mucosa of the gallbladder? Submucosa?
A
Columnar epithelium
NO submucosa
5
Q
What will relax the sphincter of Oddi?
A
Glucagon
6
Q
What is the normal size of the GB wall? Pancreatic duct?
A
GB wall: 2-4mm
Pancreatic duct: <10mm s/p chole
7
Q
Where is the highest concentration of CCK and secretin cells?
A
Duodenum
8
Q
What are Rokitansky-Aschoff sinuses?
A
Invagination of the epithelium of the wall of the gallbladder; formed from increased gallbladder pressure
9
Q
What are the ducts of Luschka?
A
Biliary ducts that can leak after chole
10
Q
What stimulates increased bile excretion?
A
CCK, secretin, vagal input
11
Q
What biochem signals cause decreased bile excretion?
A
VIP, somatostatin, sympathetic stimulation
12
Q
What are the 3 essential functions of bile?
A
Fat-soluble vitamin absorption, bilirubin excretion, cholesterol excretion
13
Q
How does the gallbladder form concentrated bile?
A
Active resorption of Na and H20
14
Q
How many times a day does the bile salt pool cycle?
A
4-8 times/day
15
Q
Where does active resorption of conjugated bile acids occur? Passive resorption of nonconjugated bile acids?
A
Active: terminal ileum (50%), passive: small intestine and colon
16
Q
Where is bile secreted from?
A
Bile canalicular cells (20%), hepatocytes (80%)
17
Q
What is the breakdown product of conjugated bilirubin that gives stool brown colon?
A
Stercobilin
18
Q
What is the breakdown product of conjugated bilirubin that gets reabsorbed and released in urine?
A
Urobilin
19
Q
Pathway of cholesterol and bile acid synthesis?
A
HMG CoA –> (HMG CoA reductase) –> cholesterol –> (7-alpha-hydroxylase) –> bile acids
20
Q
What is the rate-limiting step in cholesterol synthesis?
A
HMG CoA reductase
21
Q
What causes stones in obese people? In thin people?
A
Obese: overactive HMG CoA reductase
Thin: underactive 7-alpha-hydroxylase
22
Q
What % of the population has gallstones?
A
10%
23
Q
What % of gallstones are radiopaque?
A
10%
24
Q
What causes nonpigmented stones?
A
Increase cholesterol insolubilization; caused by stasis, calcium nucleation by mucin glycoproteins, increased water reabsorption from gallbladder; decreased lecithin and bile acids
25
What is the most common type of stone found in the US?
Nonpigmented (75%)
26
What is the most common type of stone found worldwide?
Pigmented
27
What causes pigmented stones?
Solubilization of unconjugated bilirubin with precipitation of calcium bilirubinate and insoluble salts
28
What causes black stones?
Hemolytic disorders or cirrhosis; also in pts with chronic TPN, ileal resection; increased bilirubin load, decreased hepatic function and bile stasis
29
What causes brown stones? Where are they found?
Infection causing deconjugation of bilirubin; found in CBD, formed in ducts
30
Most common bacteria causing brown stones?
E. coli
31
What pathologies need to be checked for in a patient with brown stones?
Ampullary stenosis, duodenal diverticula, abnormal sphincter of Oddi
32
Cholecystitis is caused by what?
Obstruction of the cystic duct by gallstone
33
What is suppurative cholecystitis?
Associated with frank purulence in the GB, can be associated with sepsis and shock
34
Most common organisms in acute cholecystitis?
E. coli, klebsiella, enterococcus
35
Risk factors for stone formation?
Age \>40, female, obesity, pregnancy, rapid wt loss, vagotomy, TPN, ileal resection
36
Sensitivity of US in picking up stones?
95%
37
What is the definition of biliary dyskinesia (percentage of volume excreted over certain time)?
\<40% of gallbladder volume excreted after CCK over 1 hour
38
Causes of air in the biliary system?
Previous ERCP and sphincterotomy, cholangitis, erosion of the biliary system into duodenum (gallstone ileus)
39
What are signs of acalculous cholecystitis? Pathology?
Thickened wall, RUQ pain, elevated WBCs; bile stasis leading to distention and ischemia
40
When does acalculous cholecystitis occur?
After burns, prolonged TPN, trauma, other major surgery
41
Diagnosis of acalculous cholecystitis?
US shows sludge, GB wall thickening, pericholecystic fluid; HIDA (+)
42
What is the common organism causing emphysematous gallbladder disease?
C. perfringens
43
What is gallstone ileus?
Fistula between GB and duodenum that releases stone, causing SBO; elderly, can see pneumobilia on plain film
44
Most common site of obstruction in gallstone ileus?
Terminal ileum
45
Treatment for gallstone ileus?
Remove stone with enterotomy proximal to obstruction (enterolithotomy), usually through laparotomy incision, may need bowel resection if necrosis/ischemia/perforation, inspect the whole bowel.
Perform chole and fistula resection if pt is low risk (ASA 1 or 2). If high risk, do lap chole later.
46
What is the benefit of interoperative cholangiography?
Allows for intraoperative detection of biliary injury. Studies have not definitively shown benefit in preventing injury.
47
In what % of patients does the right posterior duct enter the CBD separately? What segment is it from?
10%, segment 6 or 7
48
What is the treatment if the right posterior duct is injured during lap chole?
If \>2mm, need to open and perform hepatico-j
49
Treatment for intraop CBD injury?
* If \<50% circumference - perform primary repair
* all other cases - hepaticoj or choledochoj
50
What is the workup for persistent nausea and vomiting or jaundice following lap chole?
* US for fluid collection: if collection, perc drain
* bilious drainage: ERCP and stent vs repair
* no fluid collection, dilated hepatic ducts - concern for transected bile duct
51
Treatment for anastamotic leaks following transplant or hepaticoj?
ERCP and stents
52
Treatment for sepsis following lap chole?
Fluid resuscitation, stabilize; concern for complete transection of CBD and cholangitis
53
Most common situation in which CBD or hepatic duct strictures occur?
After lap chole
54
What is the most important cause of late postoperative biliary strictures?
Ischemia; can also be caused by chronic pancreatitis, stricture of biliary enteric anastomosis
55
Diagnosis of CBD or hepatic duct stricture?
ERCP; US will show dilated ducts
56
Treatment of CBD or hepatic duct strictures?
ERCP with sphincterotomy and possible stent placement; PTC tube if that fails
7d post injury, hepaticoj 6-8wks after injury
57
What causes hemobilia?
Fistula between bile duct and hepatic arterial system; most commonly occurs with trauma, also infections, primary gallstones, aneurysms, tumors
58
Presentation of hemobilia?
UGI bleed, jaundice, RUQP
59
Diagnosis of hemobilia? Treatment?
Angiogram; resuscitation, angio and embolization, operation if that fails
60
What is the most common cancer of the biliary tract?
Gallbladder adenocarcinoma
61
What is the most common site of mets from gallbladder adenocarcinoma?
Liver
62
Risk of cancer with porcelain gallbladder?
10-20%, need chole
63
What % of patients w/ GB cancer present with stage IV disease?
90%
64
Symptoms of gallbladder CA?
Painless jaundice 1st, then RUQ pain (could be cholangitis at this point)
Weight loss, fatigue, loss of appetite
65
Treatment based on stage of GB CA?
* Stage I (mucosa): chole
* Stage II+ (into muscle): wide resection around liver bed - 2-3cm margins, regional lymphadenectomy, may need Whipple, lobectomy or resection of CBD
66
Contraindication for lap chole?
Gallbladder CA - high incidence of tumor implants in trocar sites.
Inability to tolerate pneumoperitoneum.
General contraindications for surgery.
Not recommended in ASA III/IV or septic pts w/ milder disease.
67
5-yr survival of gallbladder CA?
5%
68
Risk factors for bile duct cancer (cholangiocarcinoma)?
C. sinensis infection, typhoid, UC, choledochal cysts, sclerosing cholangitis, congenital hepatic fibrosis, chronic bile duct infection
69
Symptoms of cholangiocarcinoma?
Early: painless jaundice, can also get cholangitis; late: wt loss, anemia, pruritis; persistent increase in alk phos and bilirubin
70
Diagnosis of cholangiocarcinoma?
* CA19-9, CEA, AFP
* Initial CT/MRI/US: dx if typical findings
* proximal lesion → MRCP: dx if typical findings
* distal lesion, or MRCP not typical → ERCP
* still not typical after ERCP → MRI/CT guided bx
71
What does the discovery of a focal bile duct stenosis in pts without h/o biliary surgery or pancreatitis suggest?
Bile duct ca
72
Where are Klatskin tumors?
In upper 1/3 of bile duct; most common type, worst prognosis
73
Treatment for Klatskin tumor?
* Lobectomy and stenting of contralateral bile duct if localized to right or left lobe; usually unresectable (MDCT, MRCP, ERCP, bx)
* Resectability often determined at surgery. Cannot have...
* retropancreatic, paraceliac nodal metastases, liver mets
* invasion of the portal vein or main hepatic artery
* extrahepatic adjacent organ invasion
* disseminated disease
74
Treatment for cholangiocarcinoma in middle 1/3? Lower 1/3?
Middle: hepaticojejunostomy
Lower: Whipple
75
5-yr survival for cholangio?
20%
76
What % of choledochal cysts are extrahepatic?
90%
77
What is the cancer risk with choledochal cysts?
15%
78
Symptoms of choledochal cyst?
Episodic pain, fever, jaundice, cholangitis
79
Choledochal cyst presentation in infants?
Similar to biliary atresia
80
Possible cause of choledochal cysts?
Abnormal reflux of pancreatic enzymes during development secondary to bad angle of insertion
81
Most common type of choledochal cyst?
Type I: saccular or fusiform dilation of extrahepatic ducts
82
Treatment for choledochal cyst?
Excision with hepaticoj and chole; type IV partially intrahepatic/type V totally intrahepatic will need liver resection
83
What patients have primary sclerosing cholangitis?
Men in 4-5th decade; associated with retroperitoneal fibrosis, Riedel's thyroiditis, pancreatitis, UC, DM
84
Symptoms of PSC?
Fatigue, fluctuating jaundice, pruritus, wt loss, RUQ pain
85
Does PSC get better after colon resection for UC?
NO
86
Consequences and complications of PSC?
Portal HTN and hepatic failure (scarring and patching with progressive fibrosis of intra/extrahepatic ducts); chirrhosis, cholangiocarcinoma
87
Diagnosis of PSC? Treatment?
ERCP showing multiple strictures and dilations; transplant needed long term, PTC drainage/choledochoj may be effective, balloon dilation for symptomatic relief
88
Treatment for pruritus symptoms in PSC.
Cholestyramine
89
Primary biliary cirrhosis occurs in what size ducts?
Medium-sized hepatic ducts
90
Consequences of PBC?
Cholestasis --\> cirrhosis --\> portal HTN
91
Symptoms of PBC?
Fatigue, pruritus, jaundice, xanthomas
92
What type of antibodies are associated with PBC?
Antimitochondrial antibodies
93
Cancer risk with PBC?
No increased risk of cancer
94
Treatment for PBC?
Transplant
95
What is Charcot's triad?
RUQ pain, jaundice, fever - indicates cholangitis
96
What is Reynold's pentad
RUQ pain, jaundice, fever, altered mental status, shock - suggests sepsis from cholangitis
97
Most common organisms in cholangitis?
E. coli and Klebsiella
98
Late complications of cholangitis?
Stricture and hepatic abscess
99
#1 serious complication of cholangitis?
Renal failure; related to sepsis
100
Most common etiology of cholangitis? Other causes?
Gallstones; also biliary strictures, neoplasm, chronic pancreatitis, congenital choledochal cysts, duodenal diverticula
101
What is the cause of systemic bacteremia from cholangitis?
At \>20mmHg, cholovenous reflux occurs --\> systemic bacteremia
102
Treatment for cholangitis?
Fluid resus, abx, ERCP with sphincterotomy nd stone extraction, if fails - PTC
103
What is oriental cholangiohepatitis?
Recurrent cholangitis from primary CBD stones; in Asia; caused by C. sinensis, A. lumbricoides, T. trichiuria, E. coli
104
Treatment for oriental cholangiohepatitis?
Hepaticoj and antiparasitic medications
105
What is the most common cause of shock following lap chole early (1st 24h)? Late (after 1st 24h)?
Early: hemorrhagic shock from clip that fell off cystic artery; late: septic shock from accidental clip on CBD with subsequent cholangitis
106
What is adenomyomatosis?
Thickened nodule of mucosa and muscle associated with Rokitansky-Aschoff sinus; not premalignant, does not cause stones; tx: chole
107
What is granular cell myoblastoma?
Benign neuroectoderm tumor of the GB; can occur in biliary tract with signs of cholecystitis; tx: chole
108
What is cholesterolosis?
Speckled cholesterol deposits on GB wall
109
What size GB polyp more likely to be malignant?
\>1cm
110
What is delta bilirubin?
Bound to albumin covalently, half-life 18d, may take a while to clear after long-standing jaundice
111
What is Mirizzi syndrome?
Compression of the common hepatic duct by a stone in the infundibulum of the GB or inflammation arising from the GB or cystic duct; causing stricture and hepatic duct obstruction
112
What abx can cause gallbladder sludging and cholestatic jaundice?
Ceftriaxone
113
What are indications for asymptomatic cholecystectomy?
Pts undergoing liver TXP or gastric bypass
