Hepatic Surgery Flashcards
where does the liver sit in dogs and cats?
cranial abdomen
where does the liver sit in relation to the midline?
2/3 of liver mass to the RHS of the midline
how many lobes is the liver of dogs and cats divided into?
4
what are the 4 liver lobes found in dogs and cats?
left
right
caudate
quadrate
what are the lobes of the liver further divided into?
sub-lobes and processes
what is the largest liver lobe in dogs and cats?
left
what structures within the abdomen is the liver attached to?
diaphragm
right kidney
lesser curvature of the stomach
proximal duodenum
what vessel runs through the liver and is strongly attached to it?
vena cava
how many sources does the liver receive blood from?
2
what are the 2 sources of blood supply to the liver?
hepatic portal vein
hepatic artery
where does blood in the hepatic portal vein come from>
digestive tract
spleen
what is the role of the hepatic portal vein?
provides blood rich in nutrients and metabolites to be broken down in the liver
what percentage of hepatic blood flow is made up by the portal vein?
70-80%
what is the role of the hepatic artery?
provides oxygenated blood to the liver
what percentage of hepatic blood flow is made up by the hepatic artery?
20%
what percentage of oxygen supply is provided by the hepatic portal vein?
50%
what percentage of oxygen supply is provided by the hepatic artery?
50%
what does blood leave the liver through?
short hepatic veins
what do hepatic veins feed into?
vena cava
where does portal and arterial blood mix in the liver?
sinusoids
whereabouts on the liver does blood exit via hepatic veins into the vena cava?
dorsal boarder of liver
what is one of the main challenges of hepatic surgery?
haemorrhage
why is haemorrhage such a risk with hepatic surgery?
liver is a highly vascular organ
why is it essential to understand the liver’s blood supply?
to understand portosystemic shunts
what aspects of a patients care may liver impairment affect?
surgery
analgesia
anaesthesia
nursing care
when will you begin to see signs of liver damage?
once 70-80% of hepatic tissue is lost
why are signs of liver damage only seen once 70-80% of hepatic tissue is lost?
liver has high functional reserve
what are the main functions of the liver?
Synthesis and clearance of proteins (Albumin)
Metabolism of nutrients (carbohydrates, lipids, amino acids)
Production / activation of clotting factors
Clearance of toxins (ammonia, drugs, etc)
Immunoregulation (Kupffer cells)
Gastrointestinal function
Storage
what is stored within the liver?
vitamins
fats
glycogen
copper
what is the potential impact of reduced liver function on synthesis and clearance of proteins (Albumin)?
affect on albumin bound drugs and anaesthetic agents
ascites
IVFT less effective due to reduction in oncotic pressure
what is the potential impact of reduced liver function on metabolism of nutrients (carbohydrates, lipids, amino acids)?
hypoglycaemia
lethargy
weight loss
what nutrients are metabolised by the liver?
carbohydrates
lipids
amino acids
what is the potential impact of reduced liver function on production / activation of clotting factors?
clotting problems
haemorrhage
what is the potential impact of reduced liver function on clearance of toxins (ammonia, drugs, etc)?
excessive sensitivity to drugs
neurological signs
PUPD
anorexia
vomiting
what is the potential impact of reduced liver function on immunoregulation?
endotoxaemia
sepsis
what is the potential impact of reduced liver function on GI function?
weight loss
diarrhoea
where are bile acids synthesised?
in the liver
how are bile acids excreted from the liver?
excreted into hepatic ducts which drain out of the liver and converge to for the common bile duct
what forms the common bile duct?
hepatic ducts which drain out of the liver and converge to for the common bile duct
what happens to bile when the body is not undergoing digestion?
bile drains from the liver and passes via the cystic duct to the gall bladder where it is stored
where is bile stored?
gall bladder
how does bile reach the gall bladder?
passes via the cystic duct from the hepatic ducts