M104 T2 L1 Flashcards
What is the largest gland in the body?
the skin
What is the second largest gland in the body?
the liver
How much does the liver weigh?
1.5 kg
What is the topography of the liver?
wedge shaped - it tapers off in a slightly triangular kind of shape
colour - reddish brown
the right side is taller
Where is the liver located?
below the diaphragm
Which quadrants does the liver encompass?
mostly in the right hypochondrium and epigastrium
but it extends into the left hypochondrium
What are the main roles of the liver?
detoxification
protein synthesis
production of bile – accessory GI organ
glycogen storage
What is the liver like in respect to tactility?
pliable to touch, easily lacerated
Why is it especially bad tha the liver is easily lacerated?
bc it’s highly vascularised so it will bleed a lot
How does the location of the liver affect the shape of the diaphragm?
it gives the diaphragm its domed shape on one side when it’s relaxed
How does the topography of the liver affect the location of the kidneys?
the mismatch in the shape of the liver between the left and right sides means that the right kidney sits lower in the abdomen than the left kidney does
What are the locational relations the liver has to other organs?
below diaphragm
right of the stomach
above the colon
overlies gallbladder
Where is the liver in relation to the ribs?
Usually covered by them but when breathing down and the contraction pushes the viscera down, it may not be covered by the ribs anymore
What are the two anterior lobes of the liver?
left and right
What are the ligaments in the liver?
coronary ligaments
falciform ligament
ligamentum teres
What ligament does the falciform ligament contain?
the ligamentum teres
What happens to the ligamentum teres after birth?
it isn’t needed anymore, so it obliterates and closes up
What are the two posterior lobes of the liver?
caudate lobe
quadrate lobe
What are the two impressions of the liver?
gastric impression
renal impression
What organ is the bare area of the liver in contact with?
the lower part of the diaphragm
Which of the four main heart vessels is in physical contact with the liver?
the IVC
Which ligaments separate the right and left lobes of the liver?
the falciform ligament
the lesser omentum ligament
What structure divides the quadrate and caudate lobes?
porta hepatis (fissure)
Which two structures does the falciform ligament link together?
the anterior abdominal wall to liver
Which two structures does the coronary ligament link together?
the diaphragm and the liver
Which two structures does the lesser omentum link together?
the liver to stomach
From where does the lesser omentum span to?
the lesser curvature stomach to the porta hepatis
What is the free margin of the lesser omentum made up of?
ventral mesentry
What does the lesser omentum enclose?
portal triad
lymph vessels
gastric vessels (close to stomach)
What structure does the coeliac trunk supply?
the foregut
What structure does the superior mesentric artery supply?
the midgut
What structure does the inferior mesentric artery supply?
the hindgut
What artery is the liver supplied by?
the hepatic artery
What vein does the liver use?
IVC
Which two veins join to make the portal vein?
the superior mesenteric vein
the splenic vein
What are the branches of the coeliac trunk / artery?
left gastric artery - supplies the stomach
splenic artery - supplies the spleen
common hepatic artery - supplies the liver
At what vertebral level does the coeliac artery exit the aorta?
T12/L1 Level
What structures does the coeliac artery supply?
liver (CHA) stomach (LGA, r&lGEAs) spleen (SA) duodenum (GDA) pancreas (SGDA) abdominal oesophagus (OB'LGA)
What is the statistical variation of the heptic artery?
40-45% of people (abnormal)
Where are the most common cases for hepatic artery variation?
Type 1 - CHA trifurcation
Type 2 - LHA joined to the LGA
Type 3 - RHA joined to the SMA
Where is the porta hepatis located?
on the visceral surface of the liver’s hilum
What’s the depth of the fissure that the porta hepatis makes?
5cm
How are the liver lobes subdivided into segments (Couinaud)?
it is according to how the hepatic artery and portal vein subdivide
Where do sinusoids (hepatic capillaries) receive blood from?
branches of the hepatic artery and the portal vein carry blood into sinusoids
What are the three types of blood vessels in the liver?
continuous - keeper
fenestrated - gaps
sinusoid
What structures does the portal triad consist of?
bile ducts
hepatic artery
portal vein
What is the function of continuous sinusoids?
to keep the blood within the vessel
What is different about liver transplants?
the liver is a regenerative organ, so only about 20% of a liver is needed for full function
the liver keeps regenerating after that, which is why people can have a portion of their liver removed to be transplanted into someone else
What cells do lobulocytes contain?
hepatocytes
What percentage of the liver is made up of hepatocytes?
60%
What are the metabolic functions of hepatocytes?
synthesises plasma proteins and bile salts
deaminates amacs to create ammonia
converts bilirubin to bile pigment
What happens to the blood from portal and hepatic veins in the sinusoids?
passes through the hepatocytes onto the central vein then the interlobular / sublobular vein they drain into hepatic veins which drains into the inferior vena cava
HEP - CENTRAL - INTERLOB - HEPATIC - HEART
Where is the central vein located?
the center of a hepatic lobule
Which vein do several central portal veins drain into?
the interlobular / sublobular vein
What does the portal venous system involve?
blood draining the GI tract towards the liver
in this way, toxins, drugs, etc absorbed from the GI has to pass through the liver before reaching the heart
What is portal hypertension caused by?
a blockage in the portal vein
the ics in pressure pushes against the vessel wall - hypertension
What are the common presentation signs of portal hypertensions?
varicoses
oesophageal varices
caput medusa
What were portacaval shunts originally used for?
to ameliorate hypertension
What did portacaval shunts involve?
a connection was made between the portal vein and the IVC
What were portacaval shunts replaced by?
transjugular intrahepatic portosystemic shunting
At what rate is bile secreted by hapatocytes?
40 ml/ hr
What are the two main hepatic ducts that bile canaliculi join to form?
the l&r hepatic ducts that drain their respective lobes
What do the left and right hepatic duct combine to form when they emerge from the liver?
the common hepatic duct
Which portal systemic anastomosis is located in the abdominal part of the oesophagus?
left gastric tributaries with oesophageal branches azygos
Which portal systemic anastomosis is located in the anal canal?
superior rectal anastomoses with middle and inferior rectal
Which portal systemic anastomosis is located in the umbilicus? was an example
paraumbilical veins with epigastric veins
What does transjugular intrahepatic portosystemic shunting involve?
the gap between the portal and hepatic vein is bridged
AAR lots of the hepatic tissue trying be perfused is not included
this lessens the vasculature load
reduces hypertension
Where are celiac lymph nodes mostly located?
around the porta hepatis
Why are they called celiac lymph nodes?
bc they are associated with the branches of the celiac artery
Where do the coeliac nodes drain into?
the cisterna chyli
What is liver trauma likely to be caused by and why?
fractured ribs could penetrate the liver quite easily
bc the liver is close to the lower ribs
penetrating wounds - anything moving through the rib cage has the potential to hit the liver
What happens if the liver is even slightly injured and why?
severe haemorrhage can happen
bc it’s highly vascularised
When might portions of the liver be removed?
liver biopsies
metastatic spread
cirrhosis
How can portions of the liver be removed?
bc the liver is segmental in nature
What vessels are included under the portal triad?
hepatic artery proper
portal vein
common bile duct
