Intensive liver care and management of acute hepatic failure

Abstract

In describing acute liver failure, the term fulminant hepatic failure (FHF) is used to denote patients with the most rapid progression, normally defined as the onset of encephalopathy within eight weeks of the onset of symptoms. For patients with a slower onset of encephalopathy, ranging from eight weeks to six months after the onset of symptoms, late-onset hepatic failure is the term used to reflect the overlap in clinical features with some patients with FHF. The importance of accurately determining the type of acute liver failure results from increasing evidence of an inverse relationship between the tempo of disease progression and the chances of recovery. Prognosis is also dependent on the underlying etiology. Principles of management are as follows: (1) an accurate recognition of the tempo of the hepatic failure—fulminant, late onset, acute on chronic—and the establishment of a likely etiology; (2) early detection and treatment of complications, particularly metabolic acidosis (early), renal failure, cerebral edema, and infection (late); (3) optimization of conditions for regeneration by maintenance of a near normal metabolic milieu (with removal of toxins by various methods of artificial liver support if necessary); and (4) early consideration of an orthotopic liver transplant for those patients in the poor prognosis group. Variations in the natural history and clinical features of acute liver failure (ALF) have led to a number of different classifications and subgroupings. Knowledge of these is important in relation to the assessment of prognosis and is even more important now that transplantation is a therapeutic option. Fulminant hepatic failure (FHF) is the term used to denote the subgroup where the tempo is greatest and is variously defined as the onset of encephalopathy within four weeks (1), six weeks (EASL, 1979) and eight weeks [as described by Trey and Davidson (2)] of the onset of symptoms, or within two weeks of the onset of jaundice (3). The patients with a more protracted course are designated by the terms subacute or late-onset hepatic failure (LOHF) (4) or subfulminant hepatic failure (3). The etiology of the hepatic failure also has a major influence on the likely prognosis.