Acute liver failure

Question 1

What is acute liver failure?

Answer 1

Rapid decline in hepatic function characterised by jaundice, coagulopathy (INR >1.5) and hepatic encephalopathy in patients w no evidence of prior liver dis

If symp occur in patient w pre-existing liver dis→ acute-on-chronic liver failure

Question 2

How is acute liver failure classified?

Answer 2

Classified depending on interval from onset of jaundice to development of encephalopathy
- Hyperacute <7d
- Acute 1-4w
- Subacute 4-12w
- Acute on chronic: decompensation in chronic liver disease

Question 3

Aetiology of acute liver failure?

Answer 3

• Paracetamol overdose (intentional/ not) most common (UK, US)
• Also assoc w drug-induced ALF: anti-microbials, herbal and dietary supplements, NSAIDs
• Hepatitis B, A, E
• Budd-Chiari synd
• Wilson’s
• Haemochromatosis
• Autoimmune hepatitis
• Deathcap mushroom (amanita phalloides)

Question 4

Risk factors for acute liver failure?

Answer 4

• Chronic alcohol use
• Poor nutritional status/ fasting
• Female sex
• Pregnancy
• Chronic Hep B
• Chronic pain and narcotic use
• Herbal and dietary supplement hepatotoxicity

Question 5

Signs and symptoms of acute liver failure?

Answer 5

• Jaundice
• Bleeding
• Encephalopathy
• Absence of history of chronic liver disease
• Abdo pain; RUQ tenderness
• N&V
• Malaise
• Signs of cerebral oedema (may have caused raised ICP)
• Hepatomegaly
• Absence of: splenomegaly, spider angiomata, palmar erythema, ascites
  
  • If ascites and splenomegaly→ acute on chronic liver failure
• Pyrexia (in liver necrosis or infection)
• Signs of cause, inclu:
  
  • Bronzed skin: haemochromatosis
  • Keyser fleischer rings: Wilson’s

Question 6

What are the 4 stages of encephalopathy?

Answer 6

• Altered mood and behaviour, disturbance of sleep pattern and dyspraxia
• Drowsiness, confusion, slurred speech and personality change
• Incoherence, restlessness, asterixis
• Coma

Question 7

Investigations for acute liver failure?

Answer 7

Identify cause
- Viral serology (inclu: hepatitis)
- Wilson’s low caeruloplasmin + high urinary copper
- Haemochromatosis: high ferritin
- Paracetamol levels
- Autoimmune antibodies: ASMA

Bloods
- LFTs: hyperbilirubinaemia, elevated liver enzymes
- Prolonged PT/ INR: INR over 1.5 (coagulopathy- defining feature)
- U&Es: elevated urea and creatinine, metabolic derangement
- FBC: leukocytosis, anaemia, thrombocytopenia
- ABG: lactic acidosis
- Low blood glucose (always check glucose)
-NB: Hypoglycaemia→ very bad prognostic sign

Urine toxin screen

Liver USS: look for alternative causes e.g. budd chiari

Ascitic tap

EEG: encephalopathy

Question 8

Management of acute liver failure?

Answer 8

Initial
- ABCDE (inclu fluid resuscitation)
- Monitor urine output, creatinine, clotting and liver function
- Prophylactic ABs and antifungals
- Treat hypoglycaemia

Transfuse FFP and Vit K

Treat underlying cause

Encephalopathy
- Monitor neurological status
- Lactulose and phosphate enemas
- Avoid sedatives- can worsen encephalopathy
- Mannitol- cerebral oedema

Renal failure
- Haemodialysis

Surgery: liver transplant

Question 9

Complications of acute liver failure?

Answer 9

• Infection
• Hypoglycaemia
• Encephalopathy
• Raised ICP
• Renal failure