18 - Prognosis and management of patients with acute liver failure

Summary

Introduction

Acute liver failure (ALF) is a devastating disease with a high fatality rate. The clinical picture closely resembles that of septic shock, with arterial hypotension, increased cardiac output and progressive multiorgan dysfunction. Cerebral oedema and intracranial hypertension are the most common causes of death. The pathophysiology of circulatory instability, multiorgan failure (MOF) and cerebral oedema is not fully understood but seems to be related to a decrease in vascular resistance and oxygen extraction, i.e. tissue metabolism. This chapter first defines ALF and then describes the most important aetiological causes of ALF. The features of ALF are then considered in relation to various prognostic markers and disease management.

Incidence and aetiology

ALF is a rare but dramatic disease that often affects previously healthy and young people. The incidence is ∼8 per million in Denmark and is probably similar in other western countries. Recently, it was estimated that there are 2000 cases of ALF each year in the USA.

The single most common cause of ALF is paracetamol intoxication, accounting for ∼50% of the ALF patients in UK and Denmark and for ∼20% of ALF patients in the USA. Acute viral hepatitis B is the predominant cause of ALF in central and southern Europe, with acute viral hepatitis E a frequent cause of subacute liver failure in India. Other causes of ALF include mushroom intoxication, drug-induced hepatotoxicity (ecstasy, halothane, valproate and disulfiram), autoimmune hepatitis, cardiac failure, and inherited metabolic diseases.