What are the grades of hepatic encephalopathy and their management?

Grades of Hepatic Encephalopathy and Their Management

Hepatic encephalopathy (HE) should be classified according to the West Haven criteria when temporal disorientation is present (grades ≥2), with the Glasgow Coma Scale added for grades III-IV, while neuropsychological or neurophysiological testing should be used to diagnose covert HE in patients with mild or no neuropsychiatric abnormalities. 1

Classification of Hepatic Encephalopathy

Types of HE

• Type A: Due to acute liver failure 1
• Type B: Due to portosystemic shunt without significant liver disease 1
• Type C: Due to cirrhosis with or without portosystemic shunt 1

Severity Grading (West Haven Criteria)

• Covert HE: Includes minimal HE and Grade I 1, 2

  • Minimal HE: No obvious clinical signs but abnormalities on neuropsychological/neurophysiological tests 1
  • Grade I: Mild alterations in consciousness, subtle personality/behavior changes, decreased attention, sleep disturbances, irritability, and difficulty with complex cognitive tasks 3

• Overt HE: Includes Grades II-IV 1

  • Grade II: Mild disorientation (especially temporal), lethargy, inappropriate behavior, asterixis, dysarthric speech, and evident alterations in psychometric tests 3
  • Grade III: Somnolence, confusion, significant disorientation, bizarre behavior 1, 4
  • Grade IV: Coma 1, 4

Time Course Classification

• Episodic: Single episode 1
• Recurrent: More than one episode over a 6-month period 1
• Persistent: No return to normal/baseline neuropsychiatric performance between episodes 1

Management Approach by Grade

General Management Principles

• A four-pronged approach is recommended for all grades of HE 1:
  1. Initiation of care for patients with altered consciousness
  2. Identification and treatment of alternative causes of altered mental status
  3. Identification and correction of precipitating factors
  4. Commencement of empirical HE treatment

Management of Covert HE (Minimal and Grade I)

• Testing for covert HE should be considered in patients with impaired quality of life, employment implications, or public safety concerns 1
• Treatment is not routinely recommended but may be considered in specific circumstances affecting daily functioning 1, 3
• Avoid sedatives when possible as they can worsen encephalopathy 3

Management of Grade II HE

• Can typically be managed on a medicine ward 3
• Lactulose is recommended as first-line treatment, titrated to achieve 2-3 soft stools per day 3
• Identify and correct precipitating factors (infections, GI bleeding, constipation, dehydration, electrolyte disturbances) 1, 3

Management of Grade III-IV HE

• Requires intensive care monitoring due to risk of airway compromise 1
• Add Glasgow Coma Scale assessment for monitoring 1
• More aggressive investigation and management of precipitating factors 5
• Lactulose administration (may require nasogastric tube in patients unable to swallow) 1
• Consider rifaximin as add-on therapy for patients with recurrent episodes 3

Important Clinical Considerations

Diagnostic Approach

• Brain imaging (CT/MRI) should be performed to exclude other causes of altered mental status, particularly for first-time HE 1
• Blood ammonia levels alone do not add diagnostic, staging, or prognostic value; a normal value should prompt diagnostic reevaluation 1
• For research purposes, diagnosis of covert HE requires at least two validated testing strategies: paper-pencil tests (PHES) plus either computerized tests or neurophysiological tests 1

Treatment Recommendations

• An episode of overt HE should be actively treated 1
• Secondary prophylaxis after an episode of overt HE is recommended 1
• Primary prophylaxis is not required except in patients with cirrhosis at high risk for developing HE 1
• Recurrent intractable overt HE, together with liver failure, is an indication for liver transplantation 1

Common Pitfalls to Avoid

• Failing to identify and treat precipitating factors, which account for nearly 90% of cases 1, 3
• Relying solely on ammonia levels for diagnosis or monitoring 1, 3
• Not considering secondary prophylaxis after the first episode of overt HE 3
• Inadequate titration of lactulose dosage to achieve 2-3 soft stools per day 3
• Confusing hepatic encephalopathy with other causes of altered mental status 3