Acute liver failure

Regarding acute liver failure, which one of the following statements is TRUE?

a) Subacute liver failure carries a better prognosis than hyperacute liver failure

b) Acute liver failure refers to ‘jaundice to encephalopathy time’ of one to four weeks

c) The commonest cause in the UK is infective hepatitis

d) Hyperglycaemia and hypokalaemia is the common metabolic derangement at

presentation

e) Deliberate self-harm patients cannot be considered for liver transplantation

Answer: b

Explanation

Acute liver failure is the triad of jaundice, coagulopathy and encephalopathy developing in the context of an individual with previously normal liver function (in order to distinguish from acute or chronic liver failure or decompensated liver disease). The timings of acute liver failure refer to the time from onset of jaundice until the development of encephalopathy. In hyperacute, this is seven days; acute is one to four weeks; and subacute is five to twelve weeks. Subacute liver failure carries the worst prognosis.
Around 70% of acute liver failure in the UK is secondary to paracetamol overdose witha much smaller proportion being caused by hepatitis. Worldwide, hepatitis B is the leading aetiology. At presentation the common metabolic derangements include  hypoglycaemia, hypokalaemia and hypo- or hypernatraemia. As well as the classical triad mentioned, patients may present with failure of virtually every organ system, posing a significant challenge to the critical care practitioner. Patients are not excluded from liver transplantation on grounds of self-induced liver failure. The criteria for consideration for liver transplantation vary with whether the case is a paracetamol overdose or of other origin and include factors such as blood pH, prothrombin time,serum creatinine, grade of encephalopathy, serum bilirubin, age of the patient andchronology.