The alimentary sytem-the liver Flashcards
what is topography
The appearance/location of something
What is the topography of the liver?
Below the diaphragm From t4/5 -right stomach above colon has a left lobe and larger right lobe Falciform ligament
What are the 4 main functions of the liver
1-Detoxification
2-Prosynthesis/ metabolism-portal system
3- bile production-GI organ
4-Glycogen storage
Describe topography posteriorly
Inferior vena cava seen laterally, and gall bladder
2 add lobes- Quadrate and caudate lobe
What is the lesser omentum and functions
Ligament from liver to stomach
Encloses: Hepatic artery, portal vein, bile duct, lymph nodes
Its medial
origins- lesser curvature- Porta hepatis
What’s the porta hepatis
The porta hepatis is a deep fissure in the inferior surface of the liver through which all the neurovascular structures
right and left hepatic ducts
right and left branches of hepatic artery
portal vein
Inferiorly- divides caudate and quadrate lobe
whats the bare area
No peritoneum- matt and opaque
Falciform ligament
Links diaphragm and abdominal wall to upper liver
Teres @ lower end
What is the round ligament
extends to umbilicus
Coronary ligament
to inferior surface of diaphragm
Blood supply
As its in foregut
Coelic artery supplies a lot- divides into- hepatic, splenic and left gastric
@t12/L1
Porta hepatis -topography
@hilum of liver- visceral surface
What are the entries and exit to porta hapatis
Hepatic portal vein- deoxy blood, nutrients, drugs and toxins-from intestines
Hepatic artery proper- brings O2 blood
Common hepatic duct
lymph and nerves
Liver lobules-
according to how the hepatic portal veins and artey divide liver
Coinauds segments
Hepatic vein and artery subdivide liver
Portal triad
Hepatic artery
Portal vein
Bile duct
What does central vein drain
THe portal triads contents
Functions of hepatic cells
Synthesis & release plasma proteins into blood albumin, ie clotting factors
De-aminates amino acids-urea in blood
Bilirubin- Bile pigment & breakdown of the haemoglobin
Bile salts- Emulsification of fats
Venous drainage: ( portal vein next to hepatic artery)
Liver sinusoid- (disc epitheium and fenestrated)- serves as a location for mixing of blood from hepatic artery and portal vein
These drain into central veins
@ centre of hepatic lobule
These drain into sublobular- hepatic- IVC
Portal system anastomoses
Communications between some branches of portal and systemic systems- portocaval anastomosis
Allows collateral return of blood to heart
Portal hypertension
Portal vein blocked- varicoses and caput medusa- oesophageal varices
Name some vessel anstamoses
- Abdominal part of oesophagus: branches from the azygos vein (which is systemic) around the oesophagus link with some from the left gastric (portal)
- Upper abdomen: veins draining the kidneys (renal), diaphragm (phrenic) and lumbar area (lumbar) join with some from the colon, duodenum, pancreas and liver (portal)
- Umbilicus: epigastric veins (systemic) draining this area of the anterior wall join the paraumbilical veins (portal)
- In the anal canal region: the middle and inferior rectal veins (systemic) link with the superior rectal (portal)
Portacaval shunt- functions
Reduce hypertension
- Diverting blood from portal to systemic system
- From portal to IVC
Portal vein converys what % to liver
70
