Week 10: liver diseases Flashcards
(120 cards)
what are the 2 sources of blood flow to the liver?
- oxygenated blood flows in from the hepatic artery (25% blood supply)
- nutrient-rich blood flows in from the hepatic portal vein (75% blood supply)
- hepatic portal vein located in the abdominal cavity
- channels blood from the GI tract and spleen -> capillary beds in the liver
what is the sources of blood flow out of the liver
hepatic vein drains blood back to the heart from liver to Inferior Vena Cava
hepatice portal vein - deoxygenated from intestines
whats the only vein that takes blood back to the heart
hepatic vein takes blood back to the heart
R sided HF causes back up and increased pressure in the hepatic vein and liver. causes congestion in the liver and impacts blood supply into the liver as well. congestion of blood flow also causes portal hypertension.
can the liver regenerate/cells regenerate
yes! however this process can get damaged (i.e fibrosis)
thru cellular replication
is the liver usually a low or high pressure system
low - so with inflammation/portal hypertension this can lead to increased pressure and varices and other abnormalities
R sided HF failure causes what to the liver
will cause congestion in the liver
what does the liver produce/what is it required for
- bile
- proteins for blood plasma
- coagulation factors
- immune factors
- carbohydrate, protein, and fat metabolism
- clears blood of: drugs, toxins, bacteria
- conjugates bilirubin
- processes hemoglobin for use of its iron content
- ammonia -> urea
- storage
bile
helps with digestion, breaks down fats to fatty acids
what protein does the liver produce
albumin
if coagulation factor in liver is damaged what happens
unlikely to clot, at risk for bleeding
when our liver is not functioning what builds up
drugs, toxins, bacteria and have a negative impact on our bodies function
what happens with unconjugated bilirubin if the liver does not do this
not water soluble, cannot be filtered by the kidneys, and is not excreted therefore in urine
what sys does elevated ammonia impact most
neuro!
what can the liver store
- glucose in the form of glycogen
- fat soluble vitamins
- water soluble vitamins
- minerals like iron and copper
- folic acid
- fatty acids
- beta globulin
what is hepatitis
- inflammation of the liver
- most often caused by a virus (A, B, C, D, E, and G) - focus on A, B, C
other causes: - chemicals and drugs: alcohol
- autoimmune disorders
- metabolic disorders
- genetic abnormalities - wilson’s disease, hemocromatosis, biliary cirrhosis
- rarely bacteria
what is wilson’s disease
copper metabolism problem -> liver cell damage from copper
what is hemochromatosis
iron absorption dysfunction
what bacteria usually affect the liver
streptococci, e. coli, salmonella
what happens in hepatitis
- widespread inflammation of liver tissue
- attacks the liver cells specifically - invaded and marked by virus, immune system begins to attack cells and snowballs into cell death and liver inflammation
- spreads into the bloodstream: fever, rash, malaise
what is the damage in acute infection of hepatitis mediated by
cytotoxic cytokines and natural killer cells
what happens in acute infection from hepatitis
- lysis of infected hepatocytes
- liver cell death (necrosis)
- results in inflammation of periportal
- liver cells can normally regenerate through cellular replication, but this may be impaired through cellular replication but this may be impaired if liver cell loss is massive
- immune-complex reaction -> rash, angioedema, arthritis, fever, malaise
clinical manifestations of acute phase of hepatitis
- maximally infective
- lasts from 1-4 mo
- mostly GI symptoms
- may have no symptoms (30% with acute hepatitis B, 80% with acute hep C)
- immunosuppressed may also have no symptoms
clinical manifestations of chronic phase of hepatitis
- begins as jaundice is disappearing
- lasts wks to mo
- many chronic pts are asymptomatic
- major complaints: malaise, easily fatigability, myalgia and arthralgia, hepatomegaly
which of the heps are more likely to result in chronic disease
hep b and c
almost all cases of hep A resolve without progression to chronic phases