Liver failure Flashcards
What is the definition of liver failure?
Recognised by the development of coagulopathy (INR > 1.5) and encephalopathy. It can occur suddenly (acute liver failure), or (more often) on a background of cirrhosis (chronic liver failure)
What is Fulminant hepatic failure?
Clinical syndrome resulting from massive necrosis of liver cells leading to severe impairment of liver function. It develops in under 2 weeks in a patient with a previously normal liver.
Cases which occur more slowly than this are known as subacute subfulminant hepatic failure
What are causes of fulminant hepatic failure?
- Viral Hepatitis - A, B, D, E
- Drugs - analgesia, MOAI, Halothane, Anti-TB, Antiepileptics
- Toxins - Carbon tetrachloride, Amantia phalloides mushrooms
- Wilson’s disease
- Acute fatty liver of pregnancy
- Budd Chiari syndrome
- Autoimmune hepaititis
What are infectious causes of liver failure?
- Viral hepatitis
- CMV
- Yellow fever
- Leptospirosis
What are causes of of acute liver failure?
- Paracetamol (acetaminophen) overdose,
- Idiosyncratic reaction to medication
- Excessive alcohol consumption
- Viral hepatitis (hepatitis A or B)
- Acute fatty liver of pregnancy
- Idiopathic (without an obvious cause)
- Wilsons disease - rare
What are causes of chronic liver failure?
- Alcohol
- Autoimmune – autoimmmune hepatitis, PBC, PSC
- Haemochromatosis
- Chronic Viral hepatitis: B & C
- Non-alcoholic fatty liver disease (NAFLD)
- Drugs (MTX, amiodarone)
- Cystic fibrosis
- A1-antitryptin deficiency
- Wilsons disease
- Vascular problems (Portal hypertension + liver disease)
- Sarcoidosis
- Amyloidosis
- Schistosomiasis
What are symptoms seen in acute liver failure?
- Jaundice
- Abdominal pain
- Nausea
- Vomiting
- Malaise
What are features of grade 1 hepatic encephalopathy?
- Sleep reversal
- Altered mood/behaviour
- Mild lack of awareness/Shortened attention span
- Impaired computations
- Dyspraxia - 5 point star
What are features of grade II hepatic encephalopathy?
- Increasing drowsiness/lethargy
- Confusion
- Slurred speech
- May have liver flap
- Personality change
What are features of grade III hepatic encephalopathy?
- Somnolence/Stuporous
- Confusion/disorientation/Incoherent
- Restless
- Asterixis
- Hyperreflexia
- Nystagmus
- Clonus
- Rigidity
What are features of grade IV hepatic encephalopathy?
Coma
How does hepatic encephalopathy occur?
As liver fails, nitrogenous waste builds up in the circulation and passes into the brain, where astrocytes clear it (by processes involving the conversion of glutamate to glutamine).
Excess glutamine causes an osmotic imbalance and a shift of fluid into these cells, leading to cerebral oedema
What signs can be present in compensated chronic liver disease?
Indicative of the cause
- Xanthelasmas
- Parotid enlargement
- Spider naevi
- Hepatomegaly
- Splenomegaly
- Palmar erythema
- Gynaecomastia
- Clubbing
- Dupuytren’s contracture
- Xanthomas
- Scratch marks
- Testicular atrophy
- Purpura
- Pigmented ulcers
What are signs of decompensated chronic liver disease/acute liver failure?
- Decreased GCS/Altered mental state
- Asterixis
- Clonus
- Nystagmus
- Hyperreflexia
- Fetor hepaticus
- Loss of proximal muscle bulk
- Ascites
- Peripheral Oedema
- JVP elevation
- Signs of cause - chronic liver disease signs - Caput medusa etc.
- Jaundice
What investigations would you consider doing in someone with suspected acute liver failure?
- Bloods - FBC, U+E’s, LFT, Clotting, glucose, paracetamol level, hepatitis screen, CMV/EBV serology, ferritin, A1-antitrypsin, caeruloplasmin, autoantibodies, blood/urine cultures, pregnancy test, ABG
- Ascitic Tap
- CXR
- AUS + Doppler flow portal veins