11.3 - Hepatic Disequilibrium Flashcards
Hepatic Portal Circulation
- allows blood from digestive tract, spleen, and pancreas to 1st pass through the liver
- allows liver to filter out toxins and metabolizes nutrients before entering circulation
- liver receives oxygenated blood from hepatic artery
- after filtration, blood exits from hepatic portal vein into inferior vena cava
Liver functions
1) detoxifies
2) produces albumin (maintains blood volume and bP)
3) Synthesizes clotting factors
Bile Secretion
- bile is made by hepatocytes (liver cells). stored in gallbladder, and secreted in duodenum
- contains bile salts, bilirubin, cholesterol, and electrolytes
- enterohepatic circulation: how bile salts are recycled
- once bile is secreted into intestine, it gets reabsorbed by intestine and transported back to the liver
Enterohepatic Circulation
- how bile salts get recycled
- after bile gets released into the intestine (to aid in digestion), it gets reabsorbed in ileum, and transported back to livr
Bilirubin Metabolism
- bilirubin is a product of RBC breakdown
- bilirubin produces the yellow tinge in jaundice
- when RBC’s breakdown, heme gets converted to unconjugated bilirubin
- unconjugated bilirubin binds to albumin to get transported to the liver
- once in liver, unconjugated bilirubin gets converted to conjugated bilirubin (makes it water soluble) to be excreted by urine
- Urobilinogen
Portal Hypertension
- increased pressure in portal venous system (due to resistance by portal bloodflow)
Complications
- esophageal varices: dilated esophagus veins
- hyperemesis: vomiting blood
- splenomegaly: enlarged spleen
- ascites: fluid buildup in abdomen
Varices
- dilated veins
- develop in response to increased pressure in portal system
- dangerous bc they can suddenly rupture and cause hemorrhage
complication of portal hypertension and cirrhosis
- ruptured varices requires intubation
Jaundice
- yellowing of skin due to excess bilirubin in the blood
Results from
1) Obstructive
- when flow of bile is blocked by liver or bile duct
2) Hemolytic
- due to excessive breakdown of RBC’s
- leads to a lot of unconjugated bilirubin (bound to albumin in bloodstream)
Ascites
- accumulation of fluid in the peritoneal cavity (abdomen)
Caused by:
1) Cirrhosis
2) portal hypertension
3) Decreased synthesis of albumin
- impaired production of albumin (by liver) causes fluid to leak out of vessels into peritoneal cavity (not enough serum protein to draw in fluid = leaks out)
Symptom: Abdominal distention
Treatment: paracentesis (drain fluid)
Hepatic Encephalopathy
- liver does not detoxify harmful substances so they accumulate in the bloodstream
- toxins affect brain function
Symptoms
- memory loss
- irritability
- confusion
- asterixis - hand tremor
Neonatal Jaundice
1) Physiological
- due to immature liver
- resolves on its own
2) Pathological
- caused by conditions: hemolytic disease, liver abnormalities
Acute Liver Failure
- liver SUDDENLY loses its ability to perform functions (NOT due to cirrhosis)
- liver can preserve its function until 70% of it is affected
Cause: acetaminophen overdose
- overwhelms livers detoxifying capacity
Treatment
- liver transplant
- charcoal drink: helps stomach absorbs drugs so your liver does not get toxified
Stages of liver Disease
- Normal Healthy Liver
- Fatty Liver
- Fibrotic Liver
- Cirrhosis
Cirrhosis
- irreversible stage of liver disease where injury leads to fibrosis/scarring
- metaplasia of hepatocytes
Cause:
- biliary cirrhosis - damage/inflammation of bile ducts = obstructed duct = cirrhosis
Manifestations
- portal hypertension
-ascites
- encephalopathy
Alcoholic Liver Disease
- chronic alcohol consumption impairs livers ability to metabolize and detoxify alcohol = inflammation and fibrosis
- spectrum of injury including:
- alcoholic fatty liver
- alcoholic cirrhosis
