Hepatic failure

Abstract

Acute liver failure is a rare multisystem disease that is characterised by the development of encephalopathy and coagulopathy within 26 weeks of the onset of symptoms in a patient with previously normal liver function. The commonest causes are viral hepatitis and acetaminophen overdose. The prognosis depends on the aetiology and the grade of encephalopathy at presentation. Because of the rapid evolution of the condition, early referral to a liver centre is important. Management is directed at the support of the cardiovascular system with volume replacement and inotropes. Continuous haemofiltration is used to manage renal failure and fluid balance. Hypoglycaemia is common and enteral nutrition should be started if possible. Patients with Grade III encephalopathy require tracheal intubation and ventilation. Cerebral oedema and raised intracranial pressure are present in more than 65% of patients with Grade IV encephalopathy, and these patients should be sedated and nursed 300 head up, with minimal stimulation. Episodes of raised intracranial pressure should be treated with boluses of mannitol. Thiopentone infusions may be needed to control raised intracranial pressure, and the use of moderate hypothermia and hypertonic saline is being investigated. Intracranial pressure monitors are used in some centres, but carry a risk of cerebral bleeding because of the coagulopathy. Liver transplantation has a major role in the management, with 50% of patients undergoing transplantation, and has improved outcome with survival rates of more than 65% after transplantation. At present, artificial liver support systems have no role in the management of patients with acute liver failure.