Liver, Biliary System And Spleen Flashcards
Liver primordium and bile duct arise from ventral endodermal outgrowth of foregut at
3rd and 4th week
Liver promordium penetrates septum transversum to become bud early in
5th week
Kupffer, hepatic stroma and hepatic vessels arise from
septum transversum mesoderm
Prolif of mesenchymal cells in dorsal mesogastrium at 5th week
Spleen promordium
Divided into eight segments corresponding to venous drainage but related to arterial blood supply and biliary drain
Segmental
French Couinaud
Two lobes divided by interlobar fissure Cantlie’s line)
Lobat (American)
Runs from left side of GB fossa to IVC
Cantlie’s line
Caudal lobe
Segment I
Segment II,III,IV
Left lobe
Segment V,VI,VII,VIII
Right lobe
Caudate lobe drains
directly to IVC
Functional unit of liver
Made up of biliary ductule, hepatic arteriole, portal venule (afferent)
Acinar unit
Portal triad
Liver zone are defined according to
Oxygen and solute concentration gradient
Closest to triad
Least susceptible to ischemic insult but most susceptible to toxic or chemical injury
Zone 1
Adjacent to terminal hepatic vein
Most susceptible to ishcemic injury
Zone 3
Bile from caudate lobe drains into
Left hepatic ductal system
GB is located under segment
4 and 5
Normal GB wall thickness
<4 mm
Source of postoperative bile leaks when correct operative technique is followed
Postulated to run from liver bed directly to GB or whether drainage ducts running from subsegments of liver along GB join cystic duct or CBD
Ducts of Luschka
Normal CBD size
<5 mm if <50 y/o
Inc by 1mm/decade after 50
Normally enlarged up to 12 mm following cholecystectomy
Relation of hepatic bile duct to right branch of porta vein
Anterior
Right hepatic artery runs
the common hepatic duct
behind
Layers of GB
Mucosa
Muscularis
Subserosa
Serosa
GB contains no
Submucosa
Mucosa lining of GB
columnar epithelium specialized for water absorption
Sinuses from invagination of epithelium through fibromuscular layer from inflammation and inc luminal pressure in GB (cholangitis, acute cholecystitis)
Rokitansky-Aschoff sinus
Hepatic artery relation to Portal Vein
Anterior
Hepatic artery relation to CBD
Medial
Exists in 17% of patients
Comes off as SMA to run lateral to CBD
Replaced right HA
Occurs in 10% of patients and usually comes off of splenic or left gastric artery
Replaced left HA
Liver tumors are supplied primarily by
Hepatic artery
True for both primary and metastatic tumor
Converges with hepatic vein before entering IVC in 80% of cases
Remaining 20% drain directly into IVC
Middle HV
Carries 75% of total blood flow to liver
Portal vein
But PV and HA give 50% of O2 supply to liver
Liver drainage
3 HVs Left HV (II, III, IV) Middle HV (V, inferior IV) Right HV (VI, VII, VIII)
There is sparing of caudate lobe in Budd Chiari because
There is a separate HV draining it directly to IVC
85% of spleen
Mononuclear phagocyte
Clearing of nucleated remnant from immature RBC, clearing of damaged or dead RBC
Red pulp
15% of spleen
Lymphoid cell, mostly B
Clearing of bloodborne antigen:
bacteria without preexistinf antibody, poorly opsonized bacteria, foreign particle, cellular debris
White pulp
BS of biliary system
Cystic artery from R HA and vein
Cystic vein absent and drainage through surface vein into liver bed
BS of spleen
Splenic artery
L gastroepiploic artery
Short gastric artery
Splenic vein posterior inferior to splenic artery and drains to PV
Innveration of liver
Sympa: T7-T10
Parasympathetic: right and left vagus
synapse with peripheral nerve fibers that run anterior and posterior to HA
Lymph drainage of liver
Perisinusoidal space of Disse and clefts of Mall
Porta hepatis
Cysterna chili
Thoracic duct
Opposite of PV blood and does not follow HV flow
Oxidation (CYP450), reduction, hydroxylation, hydrolysis to expose functional groups
Phase I
Reactions involve conjugation to alter solubility
Phase II
Dec permeability of sinusoidal epithelial cells alters lymphatic drainage leading to ascites
ascites
Rate limiting enzyme in bile acid production
cholesterol 7alpha-hydroxylase
Made primarily by endothelial cells and the liver to some degree
Restoration of normal levels in some successful liver transplants in patients with Hemophilia A
Factor 8
Nutrient stores in liver
Glycogen Triglyceride Vitamin B12 Iron Copper Fat soluble vitamin
35, F Takes OCP RUQ pain Work up: 3cm hepatic adenoma Tx?
Stop OCP and observe
If >4cm or symptoms persist, resection
Consumption thrombocytopenia
related to hepatic hemangiomata
Leads to DIC
Kasabach-Meritt Syndrome
Infection with Echinicoccus granulosum Sheep Primary host: dogs stool infecting Intermediate: humans RUQ pain, hepatomegaly, obstructive sx Leak lead to allergic symptoms Eosinophilia \+indirect agglutination 85% \+complement fixation test
Hydatid cyst
Hydatid cyst have predilection for
Right lobe of liver
Hydatid cyst abdominal CT:
cacified ectocyst, endocyst
Hydatid cyst tx
Preoperative Albendazole or Mebendazole with complete surgical removal including wall
Intraoperative aspiration with injection of saline
Hydatic cyst course
Expansion -> rupture -> spread -> anaphylaxis -> death
Most common benign liver tumor
Not related to OCP use
Hemangioma
Asymptomatic
Dx: CT contrast or MRI T2 bright
Mx: observe (asymptomatic)
Enucleation or lobectomy if with symptom or uncertain dx
Radioablation or embolization of hepatic artery for poor candidate
Complication: rupture (rare) hemorrhagic shock, acts like AV fistula, cardiac hypertrophy, CHF
Hemangioma
Common in women
Ave age: 35 years old not related to OCP
Asymptomatic
Dx: CT shows hypervascular mass with HYPODRNSE STELLATE SCAR; hot on Tc macroaggregated albumin scan
Biopsy shows hepatocyte and bile duct
Mx: observe with serial CT, if symp resect
Complication: no potential for malignant degeneration, low chance of rupture
Focal nodular hyperplasia
Reproductive age women Related to OCP use 75%- abdominal pain MRI, CT (lacks central scar) Cold on Tc macroaggregated albumin scan Biopsy: hepatocyte
Tx: discontinue OCP
<4cm observe
>4cm resect due to rupture and malignant degen
25% chance of rupture or hemorrhage
Rare malignant degeneration
Hepatic adenoma
Cholestasis, fibrotic intrahepatic and extrahepatic biliary tree
Men in 3rd-4th decade
Autoimmune associated with ulcerative colitis, retroperitoneal fibrosis, insulin dep DM, Grave’s, Sjogren’s, Riedel’s, AI pancreatitis, MG
Primary sclerosing cholangitis
PSC is associated with HLA
HLA B8
HLA DR3
PSC may progress to
Cirrhosis
Cholangiocarcinoma (20%)
PSC Dx:
Inc ALP and bilirubin
ERCP: multiple dilatation and stricture of both intra and extrahepatic biliary tree
Biopsy determine degree of fibrosis and cirrhosis
PSC Tx
None
Endo or percutaneous dilation and stent are symptomatic relief
If without significant hepatic fibrosis or cirrhosis, surgical resection of extrahepatic biliary tree with hepaticojejunostomy
Advanced: liver transplant
10-20% will have recurrence
Colectomy if with UC
Confirms diagnosis of PSC
Rule out
ERCP and liver biopsy
Cholangiocarcinoma
Most common in US (80%)
Hematogenous spread from intraabdominal infection (diverticulutis, appendicitis) or ascending infection (cholangitis)
Direct extension from intraperitoneal infection
Stent placement, manipulation, trauma
organism: Staph, Gram - (E coli, Kleb), Anaerobe (Bacteriodes fragilis)
Fever, chills, liver tenderness/enlargement, jaundice
Leukocytosis, + blood culture 40%,
Confirm with CT/UTZ
CT: HYPODENSE abscess wall enhances with IV contrast
Mx: IV antibiotics 2 weeks followed by oral (1 month)
CT UTZ guided aspiration/drain or surgical drain
Prolong antibiotics if multiple abscess
Bacterial hepatic Abscesses
Most common worldwide
Primary infection from colon spreading to liver via PV
By entamoeba hystolitica
Most commonly as single abscess on:
Fever, RUQ, chills, sweating, hepatomegaly
Antecedent diarrhea 25%
Jaundice rare
Anchovy paste abscess
Leukocytosis, abdominal liver function
Entamoeba hystolitica serology 90%
+ stool culture 15%
Radiographically similar to bacterial
Tx: metronidazole
sx reserved to failed antibiotic therapy or complication (bacterial infection)
Amoebic abscesses
Chronic inflammation
Hepatocyte destruction and regeneration
Fibrosis
Portal HTN
By alcohol, Hepa B, C, prolonged cholestasis, metabolic (Wilson, alpha 1 antitrypsin)
Cirrhosis
Most common cause of cirrhosis in US
worldwide
Alcohol
HCV
AST and ALT in CLD
> 3 times normal
AST/ALT in Alcoholic cirrhosis
> 2
Synthetic function of liver is best assessed by
PT
Anemia
Thrombocytopenia
Inc PT and INR
Inc AST and ALT >3
Cirrhosis
Confirms presence of cirrhosis and established cause
Liver biopsy
Helps determine extent of cirrhosis and predict operative mortality
Child Pugh classification
No ascites No neurologic disorder Bilirubin: <2 mgdl Albumin >3.5 mgdl PT 1-3 INR <1.7 Operative mortality: 10%
Child Pugh A
Minimal or controlled ascites Mininal or controlled neurologic disorder Bilirubin: 2-3 mgdl Albumin: 2.8-3.5 mgdl PT: 4-6 INR: 1.7-2.2 Operative mortality: 30%
Child Pugh B
Moderate-severe ascites Moderate severe COMA Bilirubin >3mgdl Albumin <2.8 mgdl PT >6 INR >2.2 Operative mortality: 70%
Child Pugh C
Child Pugh Classification
Prothrombin Bilirubin Albumin Ascites Neurologic
ProBAAN
Collaterals between short gastric veins to azygos result in
esophageal varices
Cirrhosis tx
Ascites: diuresis (spironolactone, furo), paracentesis and peritoneal jugular shunt
Acute infection of peritoneal fluid presenting with fever and abdominal pain
Most commonly by:
Suspect other etiology if polymicrobial flora and found on culture
Confirm diagnosis by >250 PMN/ul in ascitic fluid that is + culture
Treat with:
Spontaneous bacterial peritonitis
E coli
Third gen cephalosporin (cefotaxime)
Complications of cirrhosis
Variceal bleeding 33% mortaity in first episode
With rebleed 50%?
Portal HTN
Liver failure: transplant
Variceal bleed tx
Endoscopy Rubber band ligation Sclerotherapy Vasopressin Ocreotide Transjugular intrahepatic portasystemic shunt TIPS
Abnormal inc in PV pressure (>12mmHg)
Obstruction blocks flow
Inc PV pressure
Vasoconstriction
Vasodilation and inc splanchnic flow
Collaterals between portal and systemic circulation
Hepatofugal PV flow (inc blood flow in PV reversed and blood flows out of liver)
Portal HTN
Collatera between portal and systemic circulation
coronary umbilical retroperitoneal hemorrhoidal short gastric vein
occlusion of major hepatic vein results into postsinusoidal portal HTN
Budd-chiari syndrome
Extrahepatic causes of portal HTN
Portal vein thrombosis Congenital Sepsis Trauma Malignant occlusion
Intrahepatic causes of portal vein HTN
Schistosomiasis
Congenital hepatic fibrosis
Sinusoidal cause of portal HTN
Cirrhosis
Postsinusoidal cause of portal htn
Budd Chiari
Veno-occlusive disease
Budd Chiari is common in
RUQ pain
Jaundice
Ascites
Hepatosplenomegaly
Women in hypercoagulable state
Budd Chiari tx
Anticoagulant
Porta caval shunt
Porta atrial shunt
Portal HTN complication
ascites
esophageal varicea
liver failure
Portal HTN Dx
Transcutaneous liver doppler uts: parenchyma and blood flow pattern
Lab test confirms source of cirrhosis: HBV,HCV titers
Portal HTN tx
Surgical shunt: for well preserved liver function Child Pugh A and B requiring liver transplant in future >1 yr
(Portocaval and mesocaval shunt)
Liver transplant: Model for End stage Liver Disease (MELD) score
For transplant
Caused by splenic vein thrombosis
Resultant from pancreatitis
Results in esophageal varices without main PV HTN
Preserved liver function but bleeding occurs
Tx: splenectomy
Sinistral portal HTN
Occlusion of PV
Preserved liver function but my require portocaval shunt
No role for TIPS
Splenomegaly, hemorrhage
PV thrombosis
Portal vein thrombosis in childhood is caused by
umbilical vein catheterization
Portal vein thrombosis causes in adult
Malignancy HCC Cirrhosis (low heptopetal flow) Hyercoagulable state Dehydration Infection (schistosomiasis)
Dx of portal vein thrombosis confirmed by
Duplex Doppet UTZ
CTA
MRA
Portal vein thrombosis tx
Long term anticoagulation and clot lysis via transhepatic infusion through PV
50, M
Hx of HBV found to have hepatic mass
AFP elevated
Lesion is HCC
Apart from staging, what will determine resectability?
Child Pugh Classification since resection is limited to A or B
Most common cancer of liver worldwide
Men, HBV, HCV, alcohol, hemochromatosis, alpha 1 anti, PSC, hepatic adenoma, steroid use, aflatoxin exposure and pesticide
HCC
Most common cause of HCC worldwide
HBV
Majority of liver cases are
1 out of 20 malignant cases are
Metastatic lesions
HCC
Lesions in liver require cancer workup to localize primary lesion
HCC is associated with
AFP >500 ng/dl
Dx for HCC
UTZ
CT
MRI
If AFP nondiagnostic and not surgical candidate, perform in HCC
If candidate for surgery,
CXR and Chest CT to
fine needle aspiration with cytology as confirmatory
Perform exlap with or without biopsy
Rule out malignancy
For Child Pugh A and B tx
Partial hepatectomy
Neoadjuvant chemo and adjuvant for some
Transplantation for
tumor <5cm
<3 tumors
No PV or IVC involvement
Only 15-20% amenable to surgery because
tumor multicentricity
Extensive involvement of both lobes
PV invasion
Lymphatic disease
If not for surgery, perform
HA embolization or tumor cryotherapy
Radioablation
Ethanol injection
Staging of HCC
Number of tumors
Size
Vascular invasion
Overall prognosis poor 5yr survival for all comes <30%
Cancer of intra or extrahepatic bile duct Associated with PSC Ulcerative colitis Choledochal cyst Chronic bile duct infection
Cholangiocarcinoma
Parasite associated with cholangiocarcinoma
Chlonorchid sinensis
Inc ALP
Inc bilirubin
Inc GGT
NORMAL Transaminase
Cholangiocarcinoma
Cholangiocarcinoma confirmed by
ERCP
MRI
Most common location of cholangiocarcinoma
Unresectable but if amenable, attempt resection of affected liver lobe and bile duct
Upper 1/3 of cholangiocarcinoma
Middle 1/3 cholangiocarcinoma sx:
Hepaticojejunostomy
Lower 1/3 cholangiocarcinoma sx:
Whipple procedure
Cholangiocarcinoma at junction of right and left hepatic ducts
Klatskin tumor
Median survival of cholangiocarcinoma
12-59 months after resection with overall 5 yr survival 20-42%
Most common type of gallstone in US
Failure of cholesterol and Ca salts to remain in solution as result imbalance of chole, lecithin and bile acid
Cholesterol
Black stone caused by precipitation of unconjugated bilirubin with Ca -> Ca bilirubin
Found in association with hemolysis, cirrhosis, chronic TPN, ileal resection
Brown related to chronic biliary infection (E coli)
Pigmented black stones
Obstruction of pancreatic duct by stone
1/3 of acute pancreatitis cases
Gallstone pancreatitis
Less than 1%
25% of SBO in elderly who do not have adhesions
Gallstone enters intestine via cholecystoduodenal fistula
Gallstone ileus
Imaging study of choice for gallstone related diseases
RUQ ultrasound
Pain by transient obstruction of cystic duct by gallstone
Abrupt or transient RUQ epigastric pain, postprandial (fatty food)
UTZ: Gallstone on RUQ
Mx: avoidance of inciting factors
elective cholecystectomy for symptomatic patients without serious comorbidities
Biliary colic
Gallbladder inflammation by gallstone obstruction of cystic duct
RUQ pain + Murphy’s sign + fever
Normal LFT
WBC: 12-15 k/UL
RUQ UTZ: Gallstones, Gallbladder wall thickening >4mm, pericholecystic fluid, + sonographic Murphy’s sign
Mx: IV antibiotic cholecystectomy, percutaneous cholecystectomy tube in seriously ill
Acute cholecystitis
Gallstone in CBD
RUQ epigastric pain, fever, chill, jaundice, acute pancreatitis
Inc ALP/GGT
RUQ UTZ: Dilated CBD >8mm
Stone not well visualized if in distal duct
ERCP with sphincterotomy for patients with previous cholecystectomy or preoperative CBD clearance
Lap chole with intraoperative cholangiogram if preoperative clearance was not achieved
Choledocholithiasis
Bacterial infection of biliary tract
Charcot triad
Reynaud’s pentacld
RUQ UTZ: Normal biliary tree, dilated CBD >8mm without clear CBD stone does not rule out cholangitis
Supportive therapy with aggressive fluid resuscitation, electrolyte correction, broad spec IV, pain control
Timely ductal drainage: ERCP, sphincterotomy and stone extrac
Acute cholangitis
Fever
RUQ pain
Jaundice
Charcot’s triad
Reynold’s pentad
Fever RUQ pain Jaundice Hypotension Altered mental status
gallstone lodges in the ileum at distance
1-2 ft proximal to ileocecal valve
Rare 1%
Women
Associated with chronic gallbladder inflammation
Associated with porcelain gallbladder (diffuse Ca in gallbladder wall)
Asymptomatic or similar to biliary colic for extended time
Gallbladder adenocarcinoma
Gallbladder adenocarcinoma is confirmed with
UTZ
CT
MRI
MRCP
for cases incidentally found after cholecystectomy and with margins no extension through GB wall
no further treatment necessary
Gallbladder resection needs
en bloc till underlying liver depth of 2cm and regional lymphadenectomy
Survival: 5 year 5%
35 y, M
Shattered spleen after MVC
Hemodynamically unstable taken emergently to OR for splenectomy
Postop vaccine?
Pneumococcus
Meningococcus
H influenzae
Indication for splenectomy
Traumatic injury: >2 units pRBC transfusion, persistent decline in Hgb, peritonitis, significant intra-abdominal blood
Hodgkin’s: for staging if without evidence of nodal or hepatic disease
Rarely done unless staging will influence treatment
Hematologic disorder: myeloproliferative disorder, refractory idioathic thrombocytopenic purpura, thrombotic thrombocytopenic purpura, hereditary spherocytosis and thalassemia major
In children, threshold to perform splenectomy is
40ml/kg transfused blood or instability
Benign implantation of splenic tissue following splenic rupture
Retain function and clear particulate matter from RBCs with resultant norma blood smear
Splenosis
Post splenectomy complication
Pancreatic leak Abscess Left pleural effusion Infection (encapsulated) Thrombocytosis Splenic vein and PV thromboses
Clearing of damaged blood cells in the spleen occur in
red pulp
What segment in the liver will you find the GB
IV and V
72, F
Biliary obstruction
Medical factors necessitating preoperative percutaneous drainage
Cholangitis
Immunosupression
Renal insufficiency
Coagulopathy
40 y, M
UGIB from esophagea varices
Medication?
Vasopressin
Ocreotide
25, F
Protein C deficiency
Acute RUQ pain and jaundice
Occlusion of hepatic vein at IVC
SYNDROME?
Tx
Budd Chiari
Anticoagulation
75, F
RUQ pain, jaundic, fever
WBC= 16 k/uL with left shift
Next step in management?
Reynold’s pentad
Treat with aggressive fluid resuscitation
Broad spec IV antibiotics
Timely ERCP and sphincterotomy with stone extraction