liver Flashcards
what can paracetemol poisoning cause?
can cause acute liver failure from damage to the hepatocytes
> 4g/24h
why can we use a blood sample to asses if there was paracetemol poisoning?
paracetemol is zero order, linear graph, can extrapolate
effects of liver failure
- cannot make plasma proteins so oedema
- no clotting factors
- cannot metabolise drugs and toxins
- jaundice
- bleeding
- encephalopathy (toxins in brain
- portal hypertension
treatment for liver failure
transaplant
what causes chronic liver failure?
cirrhosis
liver cancer
what is cirrhosis
mixture of damage, fibrosis and regenerated liver structure
partial loss of function each time there is damage and regeneration
regenerated parts cannot work fully and properly -> loss of function gradual
cirrhosis causes chronic liver failure. what causes cirrhosis then
- alcohol
- autoimmune diseases – primary biliary cirrhosis, chronic hepatitis
- viral diseases – hepatits
- genetic – CF, haemachromatosis (Scottish people higher prevalence of this gene)
Signs and symptoms of cirrhosis
- inflamed large liver or small, shrunken and fibrosed liver
- acute bleeding from oseophageal varices (portal hypertension)
- jaundice
- oedema and ascites
- encephalopathy
- spider naevi and palmar erythema
what causes oesophageal varices
portal hypertension. pressure rises in the portal system, blood cannot drain from the veins so causes the blood to back up and flow through smaller blood vessels, including those in the esophagus
what is ascites
swollen stomach ; FLUID ACCUMULATION IN PERITONEUM
why does cirrhosis cause oedema?
- low synthesis of plasma proteins
- low plasma oncotic pressure
- fluids leave bv and accumulate in tissues
cause of encephalopathy
toxins in blood not filtered out in liver lead to brain damage and death
functions of liver
How to test for liver function?
INR normal 1.0
hepatic cell enzyme levels
o ALT, GGT raised
what is ALT GGT
alanine transaminase
Gamma-glutamyl Transferase
liver enzymes that can leak into your blood if your liver or bile duct is damaged
Treatment of liver failure
transplant
stop alcohol
artificial liver systems like MARS
managing hepatitis or autoimmune liver diseases
Hepatic disease in dentistry importance
reduce drug dosage
avoid IV sedation
NO NSAIDs
paracetemol is fine
care with antifungals
check INR before extractions due to bleeding tendency
can you use LA on liver failure patients?
yes since LA is metabolised in the plasma
is paracetemol okay for liver disease patients?
yes. even though it seems contradictory that paracetemol poisoning causes acute liver failure
jaundice arises due to?
build up of bilirubin in the skin
what does a patient with jaundice look like?
- pigmentation – yellow orange
- significant itch
- sclera of eye turns yellow
what is bilirubin
heme -> bilirubin -> CONJUGATED bilirubin-> bile
conjugated then can then be excreted from the large intestines or the kidneys
3 types of jaundice + short description
pre hepatic - increased haem load so excess unconjugated bilirubin
hepatic - Endoplasmic reticulum of the cells cannot process bilirubin
post hepatic - blocked and obstructed biliary tree/ ducts cause conjugated bilirubin to backflow
what is Pre hepatic jaundice caused by?
increased haem load beyond liver’s capacity to conjugate it
increase due to abnormal RBCs, autoimmune, wrong blood type, neonatal
what is hepatic jaundice caused by?
ER of the cells damaged from
- liver failure
- cirrhosis
- hepatitis
are stools and urine normal in pre hepatic jaundice?
yes
are stools and urine normal in hepatic jaundice?
no. both lack pigment due to ZERO conjugated bilirubin formed
rmb that UNCONGJUGATED BILIRUBIN CANNOT BE EXCRETED IN STOOLS AND URINE
post hepatic jaundice caused by?
blocked biliary ducts from
i. gall stone
ii. pancreatic cancer
iii. cholangiocarcinoma
iv. autoimmune disease that destroys the biliary tree within the liver
are the stools and urine in post hepatic jaundice normal?
no. pale stools have no pigment , urine is dark with pigment
the backflow of conjugated bilirubin from the biliary tree to the kidneys causes conjugated bilirubin to be removed via urine so its dark
what is an inflammed gall bladder called?
acute cholecystitis
how does pain arise from eating fatty foods in gall bladder inflammation?
increase fatty food => increase in bile stimulation => more contraction => more pain
how to investigate jaundice
use ultrasound or ERCP to see where there is a blockage in the biliary tree
ERCP
endoscopic retrograde cholangiopancreatography
INJECT DYE
what is cholangiocarcinoma
bile duct cancer
how does pancreatic cancer cause post hepatic jaundice
head of the pancreas swells and presses on the biliary tree
how does Cystic Fibrosis link to liver
- pancreatitis
- diabetes
- blocked ducts
- gall stones
- fibrosis
-cirrhosis
Management of pre heaptic jaundice
treat the root cause of increased haem load (autoimmune? abnormal rbcs?)
Management of post heaptic jaundice
1 remove gall stone or bladder
2 put a stent to open the ducts
3 remove cancer tumour in the bile ducts or in the pancreas
what medication can we use to prevent the build up of bile acid and thus jaundice?
o ursodeoxycholic acid
o low calorie and low cholesterol diet
how to treat neonatal jaundice?
- use blue light (phototherapy) to treat babies
