25: Chronic Liver Failure

INTRODUCTION

Chronic liver failure involves virtually every major organ system. Emergency management can be complicated and is characterized by recognition of the many complications.

The management of chronic liver failure is distinct from acute liver failure. While the management of acute liver failure is directed toward preventing early death, addressing reversible causes, and coordinating transplant, the management of chronic liver failure is centered around recognizing and managing complications. This chapter will review the most common of these complications in a system-based fashion.

EPIDEMIOLOGY, ETIOLOGY, AND OUTCOMES

The etiology of chronic liver failure differs from acute liver failure. Whereas acetaminophen, medications, viral infections, and ischemia account for the vast majority of acute liver failure cases, most cases (50%–65%) of chronic liver failure can be attributed to alcohol abuse and hepatitis C. Hepatitis B accounts for an additional 10% to 15% of cases. Although miscellaneous causes such as autoimmune hepatitis, primary biliary cirrhosis, primary sclerosing cholangitis, Wilson disease, and hemochromatosis account for only 5% of all cases, these may be more commonly represented in referral centers. Approximately 1 in 5 cases of cirrhosis are labeled as cryptogenic, although a majority of these are likely due to nonalcoholic fatty liver disease, a condition becoming increasingly prevalent in the United States, affecting 10% to 24% of the general population.¹

Regardless of the cause, progression to cirrhosis, defined as diffuse hepatic fibrosis with conversion of normal liver architecture into structurally abnormal nodules, is associated with high mortality, estimated to be as high as 50%^2,3 while awaiting transplant, and is nearly universally fatal without transplant. Chronic liver failure is responsible for 35,000 deaths per year in the United States.⁴

MENTAL STATUS CHANGES IN LIVER FAILURE

How to Evaluate Mental Status

Mental status changes can be a frequent cause for emergency department (ED) presentation and can be one of the most distressing complications from the perspective of patients and families. The most common cause is hepatic encephalopathy, caused by a combination of astrocyte swelling and cerebral edema due to the synergistic effects of excess ammonia and inflammation.⁵ As opposed to acute liver failure, elevated intracranial pressure (ICP) in chronic liver failure is much less common, reported at the case report level,^6,7 and ICP monitoring rarely plays a role unless the etiology remains in question.

Evaluation should involve ruling out other potential etiologies of altered mental status while simultaneously investigating for potential precipitants. Hepatic encephalopathy is rarely attributed solely to worsening liver function due to natural history of this disease. Common precipitants are infection and lactulose noncompliance, but also include gastrointestinal (GI) bleed, electrolyte abnormalities, constipation, and dehydration. As with congestive heart failure (CHF), identification of the precipitant is paramount.

Although hepatic encephalopathy is generally considered to be ...