Liver etc. Flashcards
Liver location
- Upper right quadrant, beneath the diaphragm. Largest internal organ
Weighs ~ 1500 grams - The liver is the largest gland in the body. It extends from the right to the left hypochondriac region (¾ of the liver is in the right superior quadrant).
- Immediately adjacent to the inferior surface of the diaphragm → location is breath-dependent (rises during exhalation, lowers during inhalation)
Superior limit height of the 5th intercostal space during exhalation
Inferior limit curve of the right costal arch during inhalation
Liver basic and major functions
Basic -
Metabolic
Secretory
Vascular
Major -
Excretion of waste products from bloodstream by excretion into bile
Four specific functions of the liver
- processing of dietary amino acids, carbohydrates, lipids and vitamins
- removal of microbes and toxins in splanchnic blood
- synthesis of plasma proteins
- detoxification and excretion into bile of endogenous waste products & pollutant xenobiotics
Hepatic artery
- Supplies O2 rich blood from heart to liver
- Provides 20-30% of blood supply to liver
Portal Vein
- Supplies nutrient rich blood from the digestive tract
- Provides 70-80% of blood to liver
Lobes of the Liver
- RIght
- Left
- Caudate
- Quadrate
Ligaments of the liver
- Falciform Ligament
- Teres Ligament
- Coronary Ligament
- Right Triangular Ligament
- Left Triangular Ligament
Ligaments of the liver are double layers of visceral peritoneum that fix the position of the liver by attaching it to the surrounding structures
Unique organ feature of the liver
The liver is the only human organ that has the remarkable property of self-regeneration. If a part of the liver is removed, the remaining parts can grow back to its original size and shape.
Coronary Ligament
Peritoneal reflection from the diaphragm to the liverDemarcates the bare area (surface of the liver with no peritoneal covering)
Falciform Ligament
Peritoneal reflection from the umbilicus to the liverRemnant of the embryonic ventral mesentery Its free edge contains the round ligament of the liver.
Hepatoduodenal ligament
Portion of the lesser omentum Extends from the porta hepatis to the superior part of the duodenum contents: hepatic artery proper, portal vein, common hepatic duct
Hepatogastric ligament
Extends from the liver to the lesser curvature of the stomach contents: gastric arteries
Round ligament (also known as ligamentum teres)
Remnant of the intra-abdominal portion of the umbilical vein Extends from the umbilicus to the liver on the free edge of the falciform ligament
Triangular Ligaments
Formed by the fusion of the anterior and posterior folds of the coronary ligament1 left and 1 right; both extend from the liver to the diaphragm
Venous Ligament
Remnant of the ductus venosus Extends from the remnant of the intra-abdominal portion of the umbilical vein to the inferior vena cava
Left and Right Fissures
Left Fissure
Impression of the round and venous ligaments
Right Fissure
Impression of the Gallbladder and Inferior Caval Vein
Liver Sinusoid
Hepatocytes are aligned radially to form the liver plate along with the sinusoids. The portal veins and hepatic artery branches terminate in the sinusoids, draining blood into the sinusoids and through the acinus to the central vein. The sinusoids are lined by fenestrated liver sinusoidal endothelial cells with Kupffer cells interspersed onto the endothelium. Between the liver plate and the sinusoids is the space of Disse, containing extracellular matrix components and hepatic stellate cells
Kuppfer Cells
Resident liver macrophages and play a critical role in maintaining liver functions. Under physiological conditions, they are the first innate immune cells and protect the liver from bacterial infections
Liver blood flow direction
- Deoxygenated blood from stomach or small intestine
- Hepatic
3.Portal Vein - venules - sinusoids
- central vein
- hepatic vein
- vena cava
Bile flow
- Bile produced in hepatocytes
- secreted into canaliculi
- bile ductules
- common duct
- gall bladder
- bile duct
- small intestine
Liver functions
The liver has more than 200 functions, including:
- Storage of Nutrients
- Breakdown of erythrocytes
- Bile Secretion
- Synthesis of plasma Proteins
- Synthesis of cholesterol
nutrients the liver stores
Hepatocytes absorb and store excess nutrients in the blood
- Glucose (glycogen)
- Iron
- Retinol (Vitamin A)
- Calciferol (Vitamin D)
Nutrients released when levels are too low
Breakdown of erythrocytes
RBC’s weaken and rupturee, releasing hemoglobin into the blood plasma.
Hemoglobin is absorbed by phagocytosis by Kuppfer cells in the liver.
Hemoglobin is split into
Heme groups
Iron is removed from heme leaving a substance called bilirubin (bile pigment).
Iron is carried to bone marrow where it is used to new hemoglobin for RBC’s
Bilirubin becomes a component of bile
Globins
Hydrolysed to amino acids and returned to the blood
Gallbladder Tests
- Abdominal ultrasound
- HIDA scan (cholescintigraphy)
In this nuclear medicine test, radioactive dye is injected intravenously and is secreted into the bile. Cholecystitis is likely if the scan shows bile doesn’t make it from the liver into the gallbladder. - Endoscopic retrograde cholangiopancreatography (ERCP): Using a flexible tube inserted through the mouth, through the stomach, and into the small intestine, a doctor can see through the tube and inject dye into the bile system ducts. Tiny surgical tools can be used to treat some gallstone conditions during ERCP.
- Magnetic resonance cholangiopancreatography (MRCP): An MRI scanner provides high-resolution images of the bile ducts, pancreas, and gallbladder. MRCP images help guide further tests and treatments.
- Endoscopic ultrasound: A tiny ultrasound probe on the end of a flexible tube is inserted through the mouth to the intestines. Endoscopic ultrasound can help detect choledocholithiasis and gallstone pancreatitis.
- Abdominal X-ray: Although they may be used to look for other problems in the abdomen, X-rays generally cannot diagnose gallbladder disease. However, X-rays may be able to detect gallstones.
Bile Content
HCO3- (Bicarbonate)
Bile salts
Bile pigment
Cholesterol