Acute liver failure is a syndrome with sudden loss of liver function characterized by transaminitis, coagulopathy, and encephalopathy in a patient without previous liver disease.
Etiologies vary greatly; however, acetaminophen toxicity and viral hepatitis infections are among the most common.
Shock, kidney failure, encephalopathy, and sepsis are common complications of acute liver failure.
High-volume plasma exchange and continuous renal replacement therapy are interventions that are associated with improved survival.
Aggressive supportive care at a center that performs liver transplantation optimizes patient outcomes.
Managing the critically ill acute liver failure (ALF) patient remains a formidable endeavor and one that requires the dedication of multiple disciplines and teams, all with a common goal to get the patient to safe harbor. This chapter briefly introduces the reader to the definition and scope of ALF as well as summarizes the common etiologies, investigations, and disease-specific interventions in an accompanying table. The crux of the chapter dives into the individual organ system critical care problems in ALF and how they are interconnected. The severe inflammation response triggered by hepatocyte necrosis and loss of synthetic, detoxification, and metabolic function of the liver contribute to the development of cerebral edema, distributive shock, acute renal failure, and other organ system involvement. An organ system approach to critical care interventions that simultaneously integrates neuroprotective strategies is essential to bridging a patient to spontaneous liver recovery in some instances and liver transplantation in others. This approach is discussed in detail and summarized in a table for quick reference. The chapter concludes with a brief overview of the current state of extracorporeal liver support in the treatment of ALF.
Alf: Description and Etiology
Acute liver failure (ALF) and acute-on-chronic liver failure (ACLF) are the two main reasons for hepatic decompensation in the context of critical care. ALF, a clinical syndrome caused by multiple inciting events (see Table 109-1 for etiologies), is characterized by transaminitis, coagulopathy, and encephalopathy occurring in 6 months or less in patients without preexisting liver disease. Conversely, ACLF describes decompensation and development of multiple organ failure in patients with preexisting liver disease and chronic portal hypertension. Distinguishing ALF from ACLF is essential to optimizing interventions; however, reliable differentiation is often problematic. For example, new hepatic insults (eg, acetaminophen toxicity or hepatic ischemia) in patients with compensated cirrhosis that results in multiple organ failure may be labeled ACLF but will follow a clinical course more analogous to ALF.
TABLE 109-1General and Etiology-Specific Laboratory Work-Up and Management for ALF ||Download (.pdf) TABLE 109-1 General and Etiology-Specific Laboratory Work-Up and Management for ALF
Example of Disease State
Management Specific to Precipitant
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Prothrombin time/INR, chemistry panel, creatinine, blood urea nitrogen, glucose, AST, ALT, alkaline phosphatase, GGT, total bilirubin, albumin, plasma ammonia, amylase ...