Liver, spleen, pancreas Flashcards
Describe the liver and the blood flow
- Right upper quadrant abdomen, right hypochondrium and right epigastrium and extends over to left hypochrondrium
- Gallbladder = crosses 9th and 10th costal cartilages, usually at border at lateral edge of right rectus muscle.
- 4 anatomical lobes
- Quadrate lobe - sometimes it shares blood supply with right Sid elver but for some people it shares blood supply with left side.
- Intraperiotenal organ except the bare area.
- Ligamentum teres= remnant of umbilical vein form placent.
Blood Flow through liver:
Functional classification liver:
The Couinaud classification of liver anatomy divides the liver into eight functionally independent segments. Each segment has its own vascular inflow, outflow and biliary drainage. In the centre of each segment there is a branch of the portal vein, hepatic artery and bile duct.
Histolofy of the Liver
Hexagonal live globule
- Each corner of hexagonal structure have series of vessels: branch from hepatic artery proper 20% (branches out to arteriole) empties in to sinusoid. Adjacent to arteriole have venue (80%- portal system) bringing nutrient rich blood from GI tract into liver. Also empties into sinusoid (leaky capillary)
- So sinusoid carrying mixed blood and will empty into central vein these connect with more central veins to then interlobular vein the interlobar vein then right and left hepatic veins to IVC
- Also have autonomic nerves coming in sitting on vessels, (sympathetic- that have synapsed in celiac ganglion and parasympathetic is vagus nerve)
- Out of liver = bile cannaliculi empties into bile duct then hepatic duct then common bile duct to be stored in gallbladder
- Lymphatic vessels also draining excess fluid from liver tissue
- Hepatocytes organised in plates and in between these are dots representing bile cannaliculi. Bile emptied into here
Feotal circulation
- Leaving placenta is umbilical vein carrying oxygenated blood from mum into liver then joins up with IVC by ductus venosus(Shunt)
- Blood leaves leaver heads to right atrium heart and is mixed oxygenated and non-oxygenated blood comes in foetal circlulation
- Bypasses lungs, shunted through and pumped from LV around aorta into circulation
- Ductos venosus becomes ligamentum venosum.
- Umbilical vein becomes ligamentum teres
Space of Disse
Outside of sinusoid, have Space of Disse:
- Hepatocyte = produces bile and empties it into bile cannaliculi
- Adjacent to space of diss is sinusoid
- Within sinusoid = Kupfer cell (phagocytic cell- engulfs foreign particles and degrades RBCs and this breakdown has bilirubin by product)
- Hepatic Stellate cell = in space of Disse, quiescent cell mainly storing vitamin A. When liver repeatedly asuslted by toxins and inflammation then these stellate cells become activated and produce collagen, hence making liver more fibrotic. They do these by converting to myofibroblast which produces collagen.
Pancreas- location and vasculature
Positioned at the level of the transpyloric place (L1). With the exception of the tail of the pancreas, it is a retroperitoneal organ, located within upper abdomen in epigastrium and left hyochondrium regions.
Vasculature of pancreas:
Supplied by branched of splenic artery. Head is additionally supplied by superior and inferior pancreaticoduodenal arteries which are branches of gasproduodenal (from coeliac trunk) and superior mesenteric arteries, respectively.
Venous draining of the head of the pancreas is into superior mesenteric branches of hepatic portal vein. Pancreatic veins draining rests of pancreas do so via splenic vein.
Nerves of pancreas
Parasympathetic = vagus nerve (CNX)
Sympathetic = greater and lesser splanchnic nerves
Duct of the pancreas
Exocrine pancreas: Intercalated ducts with draining adjacent lobules drain into network od ontralobular collecting ducts, which drain into main pancreatic duct which unites with communal bile duct forming hepatopancreatic ampulla of Vater. This opens into duodenum via major duodenal papilla.
Secretions into duodenum are controlled by muscular valve- sphincter of Oddi. It surrounds the Ampulla of Vater, acting as a valve.
Lymphatics of the pancreas
drained by lymphatic vessels that follow arterial supply. Empty into pancreaticosplenal nodes and pyloric nodes, which drain into superior mesenteric and coeliac lymph nodes.
Portal vein formation
Formed from splenic vein (receives IMV) and SMV. Gastric veins also come in. This receives products of digestion from stomsch, spleen, IMV and SMV so small intestine, caecum.
Colon and proximal 2.3 transverse colon. Coming in relatively low pressure so blood cleans an processed before venous blood returned.
Causes of Portal vein hypertension
intra hepaticc-> reasons within the liver causing increased pressure (cirrhosis)
Pre-hepatic -> Thrombosis in vein…
Post- hepatic = associated with outflow of blood from liver
3 main site sportal vein hypertension and the consequences
3 main sites:
- Umbilical vein
- Oesophagus
- Superior rectal artery
Consequences: Varicosed veins that become distended in the sites can rupture snd cause bleeding, liver can no longer carry out normal functions like it wood.
hyperglycaemia, hepatic encephalopathy , crude not broken down do coagulation problems.
The Bilary Tree
Bile= emulsify fats in small intestine and substance like bilirubin that we want to eliminate in body carried by bile.
Coming into liver at portahepatis
Left hepatic duct and right hepatic duct from subsequent lobes liver from common hepatic duct then cystic duct to gallbladder then common bile duct which unites with main pancreatic duct.Common bile duct units with main pancreatic duct to go into duodenum and ampulla of Vader with spinchter of oddi. Pass through pancreas as empty into duodenum (2nd part)
Functions of the spleen
Functions Blood filter, removing old red blood cells and also plays a role in both cell mediated and humeral immune responses.
Locstion of the spleen
Upper left quadrant under cover of diaphragm and ribcage.
Connected to stomach and kidney by parts of greater omentum.
- Gastrosplenic ligament
- Splenorenal ligament.
Vasculature and lymphatics of the spleen
Vasculature: Most arterial blood wispily from splenic artery (arises from coeliac trunk). This branches to 5 vessels as it reaches the spleen and these don’t anastomose with each other. Venous draining through splenic vein.
Innervation: coeliac plexus
Lymphatics: follow splenic vessels and drain into pancreaticosplenic lymph nodes and ugltimates coeliac nodes.
Whta is bilirubin, the types and its metabolism
A waste product from the breakdown of RBCs. It is yellow hence why it causes people to go yellow
Why do people become jaundices = lots of reasons…
Unconjugated = cant be excreted but conjugated can.
3 types jaundice
Liver function tests
Pancreatic cancer- most common is pancreatic ductal adenocarcinoma-
Benign Prostaic cancer tumours
Descroibe these liver function tests
As there is impaired synthetic function this indicates that the liver is no longer working as it should, and therefore has ‘decompensated’ secondary to alcoholic liver disease.
