Hepatic encephalopathy
Alerts and Notices
Synopsis
- Patients with severe hepatic encephalopathy may require urgent airway intervention.
- Patients may demonstrate hemodynamic instability due to an acute precipitant of hepatic encephalopathy, including gastrointestinal hemorrhage or infection. Assess and resuscitate accordingly.
- Avoid the use of benzodiazepines for induction during intubation due to impaired metabolism and worsening delirium.
- Resuscitate patient and evaluate airway and hemodynamic stability.
Hepatic encephalopathy (HE) is characterized by a constellation of neuropsychiatric symptoms that occur as a result of decompensated liver disease. Although the pathology is not fully understood, it is thought to be related to an increase in neurotoxins such as ammonia, as well as changes to inflammatory mediators and cerebral blood flow.
HE can occur either in acute liver failure or as a result of worsening chronic disease, and it has been associated with transjugular intrahepatic portosystemic shunts (TIPS) due to changes in portal blood flow. The prevalence of HE is estimated to be 17%-20% with a 5-year incidence of more than 40%. The vast majority of patients presenting to the emergency department (ED) for HE will ultimately require admission, and morbidity and mortality are high. In 2016, an estimated 53 000 United States ED visits were related to HE.
While the signs and symptoms of HE are neuropsychiatric and range from mild confusion or disorientation to somnolence or coma, HE is frequently seen in patients with underlying chronic liver disease and associated stigmata (ie, jaundice, spider telangiectasias, ascites, hypotension).
HE is graded according to the West Haven criteria:
- Grade 1 includes mild decreased attention span, hypersomnia, slowness of thinking, mood changes, and slight confusion.
- Grade 2 includes lethargy, disorientation (especially to time), dysarthria, asterixis, and personality changes.
- Grade 3 includes disorientation to time and place, somnolence, disordered speech, memory impairment, and marked confusion.
- Grade 4 progresses to coma.
HE can be precipitated by medication or drug ingestions, including hepatotoxins such as Amanita phalloides. Pregnancy, alcohol use disorder, poor nutrition, and chronic hepatitis are all risk factors. Among the proximate causes for episodes of HE, infection (and specifically spontaneous bacterial peritonitis, or SBP) is the most common, followed by electrolyte abnormalities, bowel dysfunction or constipation, and gastrointestinal bleeding.
The emergency management of HE includes a careful history and physical examination, assessment for other possible causes of encephalopathy or altered mental status, airway assessment, and resuscitative efforts with cautious fluid management. Lactulose is a mainstay of acute care management.
Codes
ICD10CM:K76.82 – Hepatic encephalopathy
SNOMEDCT:
13920009 – Hepatic encephalopathy
Look For
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Diagnostic Pearls
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Differential Diagnosis & Pitfalls
The principal feature of HE is altered mental status; the differential is consequently broad:- Toxic ingestion (eg, illicit drugs [eg, opioid toxicity], toxic alcohols, overdoses of prescription medication)
- Polypharmacy
- Sepsis due to central nervous system infection or other source
- Endocrine pathology (ie, thyroid, pituitary, parathyroid changes, glycemic dysfunction)
- Renal failure
- Liver failure
- Hematologic disease (ie, anemia, thrombocytosis, polycythemia)
- Hypercarbia, hypoxemia from pulmonary disease
- Intracranial hemorrhage, malignancy, or edema
- Primary psychiatric disorder
Best Tests
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Management Pearls
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Therapy
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Drug Reaction Data
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.Subscription Required
References
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Last Reviewed:03/21/2023
Last Updated:04/03/2023
Last Updated:04/03/2023