8 - Liver, Biliary, Pancreas, Spleen Flashcards
What 3 things does the liver synthesize?
- Plasma proteins (albumin)
- Coag factors
- Bile acids
What 4 things does the liver metabolize?
- Nutrients (CHO, lipids, proteins)
- Drugs
- Toxins
- Vitamins and minerals
What are the 2 main surfaces of the liver?
Diaphragmatic and visceral
What are the 6 lobes of the liver?
- R lateral
- R medial
- Quadrate
- L medial
- L lateral
- Caudate (caudate and papillary processes)
What is the afferent blood supply to the liver?
Portal system = portal vein
Arterial system = aorta
What provides the liver with most of the hepatic blood supply?
portal vein
What supplies most liver tumors with their blood supply?
aorta
What is the efferent blood supply from the liver and where does it drain?
hepatic veins –> caudal vena cava
What are the 2 main arterial branches that supply the liver and what is the major artery they come off of?
Celiac artery –> Hepatic a. –> R and L lateral branches
1
hepatic artery
2
gastroduodenal artery
3
L branch of the hepatic artery
4
branches to the left lobes
5
right branch of the hepatic artery
6
R gastroepiploic artery
7
L gastric artery
8
splenic artery
9
angiographic catheter
What does the R portal branch supply?
R lateral lobe
Caudate process
What does the L portal branch supply?
R medial, Quadrate, L medial, L lateral, papillary process
What is the normal portal pressure?
8-12 mmHg
What are the 3 main hepatic veins? Which one is largest and what does it drain?
- Right
- Middle/central
- Left = largest –> drains L lateral, L medial, quadrate, part of R medial
1
caudal vena cava
2
R hepatic vein
3
L hepatic vein
4
Branches to L lobes
5
middle hepatic vein
6
branch to papillary process
7
R renal vein
8
angiographic catheter
9
occlusion balloon
Why would liver dysfunction lead to coagulopathy?
Clotting factors are not sufficient in #
What would hypoproteinemia due to liver dysfunction lead to?
Delayed wound healing (albumin <2g/dL)
Ascites
When does hypoalbuminemia occur?
When there is ~70% loss of helpatic functional capacity
What can impaired immune function due to liver dysfunction lead to?
Increased risk for sepsis
What is the function of the gall bladder?
Bile storage
Where is the gall bladder?
Between R medial and quadrate lobes
What forms the common bile duct?
Cystic duct + hepatic ducts
In dogs, where do the CBD and pancreatic duct join?
At the major duodenal papilla
In cats, where do the CBD and the pancreatic duct join?
Prior to entering the major duodenal papilla
What is different about the duodenal papilla of dogs compared to cats?
Dogs have a minor duodenal papilla in addition to a major one
The GB contracts when stimulated by _____.
cholecystokinin
What is the route of bile?
R/L hepatic ducts –> cystic duct –> common bile duct –> major duodenal papilla
What are 3 ways by which we can get a liver biopsy?
- Percutaneous
- Laparoscopic cup biopsy
- Open
What are 3 types of percutaneous biopsies?
- FNA
- Core biopsy
- Ultrasound guided
What are 3 types of open liver biopsies?
- Wedge
- Punch
- Guillotine
What is not an absolute contraindication for surgical biopsies? What method may be preferred for this?
Coagulopathy;
Laparoscopic may be preferred
What are advantages to laparascopic liver biopsies?
- Minimally invasive
- illumination, magnification
- Larger samples obtained
What are the disadvantages to laparascopic liver biopsies?
- Have to wait until it clots
- Specialized/expensive equipment needed
What are punch biopsies good for?
Parenchymal lesions not at the margins
In a punch biopsy of the liver, penetration of _____ thickness should be avoided.
>1/2
What can be used to facilitate coagulation after taking a liver punch biopsy?
Absorbable gelatin sponge
Punch biopsies of the liver are good for lesions in the _____.
middle of a lobe
What is a guillotine technique for taking a liver biopsy?
Loop of suture is placed around protruding margin, is pulled tight crushing though parenchyma, and the hepatic tissue is amputated ~5 mm distal to ligature
Guillotine liver biopsies are meant for lesions at the ____ of the lobe.
edge
What is a wedge liver biopsy?
Several overlapping mattress sutures are placed, crushing through tissues but not cutting through –> wedge excised
What can be a problem with a partial liver lobectomy?
hemorrhage
What is the ideal closure device for a partial liver lobectomy?
Thoracoabdominal stapler
What are 3 things that can be done with a liver biopsy?
- Histopath
- Copper analysis
- Culture
What would be considered a “bad” biopsy sample?
Too small, crushed, not representative of disease
What is the most common problem that can arise from a liver biopsy?
hemorrhage
What is a portosystemic shunt?
Anomalous vessels allowing blood to bypass the liver parenchyma and enter systemic circulation directly;
Abnormal communication bt the portal venous system and the systemic venous system
What are the 2 common types of PSSs?
extrahepatic vs. intrahepatic
What are the 3 types of portal vein hypoplasia?
- Portal vein hypolasia - microvascular dysplasia
- Portal vein hypoplasia with portal hypertension
- Idiopathic non-cirrhotic portal hypertension
What are 3 possible hepatic vascular anomalies?
- PSS
- Portal vein hypoplasia
- Hepatic arteriovenous fistulas
What can the hepatic vascular anomalies lead to?
Hepatic encephalopathy
Small and toy dog breeds tend to have _____ shunts.
extrahepatic
Large breed dogs tend to have _____ shunts.
intrahepatic
What type of PSS do cats usually have and what is a clinical sign to look for?
Extrahepatic; look for copper-colored eyes
What are the 2 types of extrahepatic shunts and how many of them are there usually?
Congenital (usually single)
Acquired (usually multiple)
_____ _____ shunts are usually a result of portal hypertension.
Acquired extrahepatic
Intrahepatic shunts are usually _____ and _____.
congenital, single
What tests should be run when a PSS is suspected?
Chem, CBC, UA, serum bile acids, ammonia levels
What findings could be seen on abdominal rads when there is a PSS?
Microhepatica +/- cystic calculi
What imaging is essential for definitive diagnosis of a PSS shunt?
- Abdominal ultrasound
- CT angiogram
- Positive contrast portography
- Nuclear scintigraphy (Technesium 99 pertechnetate)
What finding on a CBC is consistent with a PSS?
Microcytosis (60-72%) because there is not appropriate iron transport
What findings on a chem are consistent with a PSS?
- +/- elevated liver enzymes
- Decreased albumin, glucose, urea, cholesterol
What finding on a bile acids test is consistent with a PSS?
Very elevated
What findings on an ammonia test is consistent with a PSS?
usually is elevated
Why is a CT angiogram the preferred imaging for a PSS Dx?
It is the most sensitive and plausible to do (91%)
How long is medical treatment required for PVH-MVD?
lifelong
What is the goal of medical treatment for hepatic vascular anomalies?
Minimize signs of and risk for hepatic encephalopathy;
Decrease protein = decrease ammonia
What are the 6 main things that should be done in medical treatment for hepatic vascular anomalies?
- Low protein diet
- Oral antibiotic (amoxi/ampicillin)
- Lactulose
- Anti-seizure
- Hepatoprotective
- GI protectants (esp. intrahepatic shunts)
What is the treatment of choice for definitive treatment of a PSS?
GRADUAL attenuation of the shunting vessel with an ameroid ring constrictor, cellophane banding, or hydraulic occluder.
What is a method that can be used to intervene when it is not possible to close an intrahepatic shunt surgically?
Interventional radiology: Percutaneous transjugular caval stent and coil embolization
What is the prognosis for animals that survive perioperative period for PSS repair?
good to excellent
What are 2 common indications for extrahepatic biliary surgery?
- Extrahepatic biliary obstruction
- Biliary mucocele
What is a gallbladder mucocele?
Distention of GB by inappropriate accumulation of mucus
What does a gallbladder mucocele cause?
Decreased bile flow, decreased GB motility, altered water absorption;
Can lead to GB rupture - bile peritonitis
What breed is predisposed to gallbladder mucoceles?
Shetland sheepdogs
What other diseases are GB mucoceles associated with?
Hyperadrenocorticism, hypothyroidism, IBD
What are clinical signs associated with a GB mucocele?
Vomiting, inappetance, jaundice, lethargy
What are chem findings consistent with a GB mucocele?
Increased ALT, ALP, bilirubin
What is a finding on abdominal US that is consistent with a GB mucocele?
“Stellate” or “kiwi fruit” appearance
What is the preferred treatment for a GB mucocele?
Cholecystectomy
What are contraindications for a cholecystectomy?
- CBD not patent
- Hepatic ducts compromised
