Liver and Biliary Surgery Flashcards
what are the liver lobes
left lateral
left medial
quadrate
right medial
right lateral
caudate (caudate process + papillary process)
where is the gallbladder located
between the quadrate and right medial liver lobes
cystic duct
connects the gallbladder to the first hepatic duct
hepatic ducts
connects the liver to the cystic and common bile ducts
dogs: 2-7 hepatic ducts
cats: 1-5 hepatic ducts
common bile duct
connects the cystic duct to the major duodenal papilla in the duodenum
hepatic blood supply
dual blood supply
- hepatic artery
- portal vein
hepatic artery
supplies 20% of blood supply and 50% of oxygen
cystic artery branches off to supply the gallbladder
portal vein
provides 80% of blood supply and 50% of oxygen to the liver
hepatic veins
drains deoxygenated blood from the liver into the caudal vena cava
major duodenal papilla
exit point for the common bile duct and pancreatic duct into the duodenum
- dogs: CBD and PD enter separately
- cats: CBD and PD fuse prior to exiting
minor duodenal papilla
exit point for the accessory pancreatic duct
- dogs: majority of pancreatic secretions into duodenum
- cats: only 20% of cats have accessory pancreatic duct
what are preop considerations for liver surgery
- hemorrhage - always run coag panels b/c liver is highly perfused
- anesthesia & drug metabolism - avoid drugs that rely on the liver
- antimicrobials - clavamox, clindamycin, or 3rd gen cephalosporins
is it better to sample bile or liver parenchyma for cultures
bile
many animals have resident hepatic flora of enteric origin - sampling is likely to not be diagnostic
what are the 4 techniques for liver biopsy
- suture fracture
- overlapping suture
- skin punch biopsy
- laparoscopic
suture fracture biopsy
used for DIFFUSE hepatopathies
use 3-0 or 4-0 PDS to ligate and cut through parenchyma on the tip of a liver lobe
overlapping suture biopsy
used for areas that are not easily looped around with suture
take overlapping suture bites then cut around the area of interest
skin punch biopsy
used to sample areas away from the margin of the lobe
can fill the hole with gelatin sponge for homeostasis
laparoscopic biopsy
less invasive
best for diffuse hepatopathies
what are 4 surgical hepatobiliary diseases
- hepatic neoplasia
- extra hepatic biliary duct obstruction
- bile peritonitis
- gallbladder mucoceles
how is hepatic neoplasia diagnosed
abdominal ultrasound
FNA/core biopsies are NOT always diagnostic and high risk of hemorrhage
surgery for hepatic neoplasia
liver resection
can resect up to 75% of liver mass
common causes of EHBDO in dogs
extraluminal:
- pancreatitis
- pancreatic abscess
- neoplasia
intraluminal:
- cholelithiasis
- foreign body
- neoplasia
intramural:
- neoplasia
common causes of EHBDO in cats
inflammatory:
- cholangiohepatitis, cystitis, or lithiasis
- pancreatitis
- hepatic lipidosis
neoplasia
- pancreatic adenocarcinoma
- biliary adenocarcinoma
diagnostics for EHBDO
- hyperbilirubinemia
- hypercholesterolemia
- cholestatic hepatopathy
abdominal US: CBD and GB distention, choleliths, masses, mucoceles
bile peritonitis
bile leakage into the abdominal cavity due to gallbladder or biliary tree rupture
caused by trauma, necrotizing cholecystitis, ruptured mucoceles, EHBDO
can cause septic peritonitis if bile is infected
how is bile peritonitis diagnosed
abdominocentesis
- fluid bilirubin >2x serum
abdominal fluid cytology
- bile pigments present
surgery for bile peritonitis
repair the cause of the leakage (rupture site) and lavage
gallbladder mucoceles
gel-like, congealed bile filling the gallbladder
caused by cystic mucinous hyperplasia
diagnosis of gallbladder mucoceles
abdominal ultrasound
early: bile sludge accumulation
late: stellate/”kiwi” appearance of gallbladder
thickened gallbladder wall with hyperechoic surroundings
surgery for gallbladder mucoceles
cholecystectomy - removal of the gallbladder
other options:
- rerouting - connecting GB directly to the duodenum (requires a healthy GB)
- biliary stent - used to repair bile duct trauma
- cholecystostomy - draining the gallbladder (risk of bile peritonitis)
what surgery should be performed if you cannot determine the patency of the CBD
biliary rerouting
what surgery should be performed if you’re unable to catheterize a functional EHBDO
biliary stent
OR
cholecystostomy
what surgery should be performed for biliary mucoceles, choleliths, GB neoplasia, or trauma
cholecystectomy
what surgery should be performed if there is trauma or rupture of the CBD
primary closure +/- stent or biliary rerouting
what is the mortality rate for hepatobiliary surgery
HIGH - requires intensive postoperative management
complications:
- bile leakage/peritonitis
- hemorrhage
- pancreatitis
- re-obstruction
- sepsis
