ACUTE LIVER FAILURE
Epidemiology
Acute liver failure (ALF) is an uncommon disorder that
leads to jaundice, coagulopathy, and multisystem organ
failure. The development of hepatic encephalopathy
within 8 weeks after the onset of jaundice in patients
with no known chronic liver disease defines ALF.127 ALF
affects approximately 2000 people per year in the United
States,128 with acetaminophen overdose the cause in a
majority of the cases.129 Mortality from fulminant hepatic
failure (FHF) can be high (60% to 80%) in the absence of
liver transplantation, depending on the cause.130 Causes
of death are mainly multisystem organ failure, sepsis, and
cerebral edema. Liver transplantation for ALF generally
has a worse outcome than transplantation for chronic
liver disease because of the high postoperative mortality
caused by sepsis and multiorgan failure.131
Prognostic Factors in Acute Liver Failure
The timing of transplantation and the selection of
patients are crucial because transplantation is the only
therapeutic intervention proved to be beneficial.132
Although scoring systems have been proposed, the myriad
causes of ALF limit their accuracy (Fig. 101-5). Most
case series are limited in number, and some span long
periods during which supportive therapies may have
changed. The King’s College criteria have been shown to
have good specificity (94.6%) for patients who will die
without transplantation but lower sensitivity (58.2%),
thus suggesting that a proportion of patients will die
and not fulfill the criteria.133 The criteria also have low
negative predictive value, which could lead to transplantation
in a patient who would have recovered without
surgery. Other predictors include the Model for End-
Stage Liver Disease (MELD),134 which has been shown
to be an excellent predictor of outcome in patients with
ALF of various causes, excluding acetaminophen.135
Blood lactate levels136 and hyperphosphatemia137 are
also promising.