Liver failure, acute

K72.0

DESCRIPTION

Acute liver failure is a devastating clinical syndrome which has a high mortality. It results from massive necrosis of liver cells leading to the development of hepatic encephalopathy. The clinical appearance can be deceptive and it is easy to underestimate how critically ill these patients are. Refer patients early to secondary or tertiary hospital. Paediatric acute liver failure is said to be present once the INR is greater than 2 (not correctable with vitamin K), or greater than 1.5 in the presence of encephalopathy.

The following complications can occur:

  • coagulopathy,
  • hypoglycaemia,
  • cerebral oedema,
  • renal failure,
  • encephalopathy,
  • cardiorespiratory failure,
  • metabolic acidosis, and
  • sepsis.

DIAGNOSTIC CRITERIA

Clinical

Appears deceptively well in the early stages. Progressive features include:

  • malaise,
  • vomiting,
  • stupor,
  • anorexia,
  • encephalopathy,
  • foetor hepaticus,
  • bleeding tendency,
  • ascites, and
  • jaundice.

The absence of jaundice suggests another process, such as Reye syndrome, which also leads to hepatic encephalopathy.

Investigations

  • Raised or low liver enzymes, low serum albumin, raised bilirubin, raised blood ammonia, hypoglycaemia.
  • Prolonged prothrombin time/INR.
  • Low fibrinogen.

GENERAL AND SUPPORTIVE MEASURES

  • Admit to high care or intensive care unit.
  • Monitor:
    • blood pressure,
    • urine output,
    • heart rate,
    • neurological state,
    • respiration,
    • gastro-intestinal bleeding,
    • haematocrit,
    • blood glucose – 3 hourly if comatose,
    • acid-base status,
    • liver and renal functions,
    • coagulation competence (INR),
    • electrolytes: sodium, potassium, calcium and phosphate, magnesium.
  • Maintain hydration.
  • With encephalopathy, aim to reduce ammonia production by the gut and optimise renal excretion.
  • Withdraw protein intake completely initially followed by restricted intake if level of consciousness improves, i.e. 0.5-1 g/kg/24 hours.
  • Stop sedatives, diuretics and hepatotoxic medicines, if possible.

MEDICINE TREATMENT

To reduce intestinal protein absorption:

  • Lactulose, oral, 1 g/kg/dose (1.5 mL/kg/dose) 4–8 hourly via nasogastric tube, then adjust dose to produce 2-3 soft stools daily.
    OR
  • Polyethylene glycol 59 g/L solution with sodium sulphate and electrolytes, oral/ nasogastric tube, 10–25 mL/kg/hour until clear fluid is passed rectally (about 4–6 hours).
    • No additional ingredient should be added to the solution, e.g. flavourings or sugar containing cold drinks.
    • Follow with regular lactulose to keep stool loose.
  • Gentamicin, oral, 12.5 mg/kg/dose 6 hourly for 5 days.
  • The intravenous formulation can be given orally.

Cerebral oedema:

For management of cerebral oedema, see Status epilepticus (convulsive) .

For pre-operative use or with active bleeding:

  • Fresh frozen plasma, IV, 20 mL/kg administered over 2 hours.
    OR
  • Lyophilised plasma (fresh dried plasma), IV, 20 mL/kg administered over 2 hours.
  • Vitamin K1 (phytomenodione), IV, 2.5–10 mg daily.
  • Monitor response to vitamin K1 with INR and PTT.

If platelet count < 10 x 10⁹/L or if < 50 and with active bleeding:

  • Platelet transfusion.

For gastrointestinal bleeding:

  • Omeprazole, oral. 0.7-1.4 mg/kg/day once daily. Specialist initiated.
    • Maximum dose: 20–40 mg/dose.
      If 1 month–2 years: 5 mg once daily.
      If > 2–6 years: 10 mg once daily.
      If > 7–12 years: 20 mg once daily.

LoE: III[8]

For hypoglycaemia:

  • Dextrose 10%, IV bolus 5 mL/kg.
  • Administer maintenance as below.

Maintenance of fluids until enteral feeding resumed:

  • ½ Darrows/dextrose 5%, IV, 60–80 mL/kg/day.
  • Ensure a minimum of 3–6 mmol/kg/day of potassium.
  • Avoid diuretics.

For anaemia:

  • Packed red cells, 10 mL/kg over 3 hours if haemoglobin < 7 g/dL.

For shock:
See Shock .

For sedation, if essential:

  • Midazolam, IV, 0.1 mg/kg.
    • Benzodiazepines are poorly metabolised in liver failure and may result in prolonged sedation.
    • Do not repeat without clinical indication.

Seizures are often subclinical or subtle. For seizures:

  • Diazepam, IV, 0.2 mg/kg
    • Repeat dose if not controlled in 5 minutes.
    • Benzodiazepines are poorly metabolised in liver failure and may result in prolonged sedation.
    • Do not repeat without clinical indication.

Antibiotic therapy

Where sepsis is suspected, prevent and treat aggressively with intravenous broad spectrum antibiotics. Empiric antibiotic therapy until cultures is known.

  • Ampicillin, IV, 50 mg/kg/dose, 6 hourly.
    PLUS
  • Cefotaxime, IV, 75 mg/kg/dose, 8 hourly.

REFERRAL

  • All for determination of the underlying cause after initiation of treatment.
  • Combined hepato-renal failure.
  • Failure to contain bleeding.