2.5 Hepatic Encephalopathy (Refractory cases)

Hepatic Encephalopathy (Refractory Cases) — Structured Lecture Summary

Lecturer: Prof. Sanjaya Satapathy, MD, FAASLD

Module: 2.5 | Pre-Transplant Hepatology Series

1. Main Clinical Topics Discussed

• Definition, classification, and spectrum of hepatic encephalopathy (HE)
• Identification and management of precipitating factors
• Evidence-based pharmacologic management (lactulose, rifaximin)
• Refractory HE: evaluation, imaging, and shunt embolization
• Nutritional principles and medication safety in HE
• Transplant referral thresholds and prognostic implications

2. Key Learning Points, Guidelines, and Recommendations

Classification of HE

• Type A: Associated with acute liver failure; distinct pathophysiology and prognosis
• Type B: Portosystemic shunting without intrinsic liver disease (e.g., surgical or spontaneous shunts)
• Type C: Most common; occurs in cirrhosis with portal hypertension — the primary focus of this lecture
• Severity grading:

- *Covert/Minimal HE:* Subtle cognitive deficits (attention, executive function, sleep-wake disturbances); not apparent on routine examination

- *Overt HE:* Clinically evident; graded via West Haven Criteria (Grades 2–4), with progressive impairment in consciousness, orientation, and neuromuscular function (e.g., asterixis)

Precipitating Factors — Always Identify First

• Infection (SBP, UTI, pneumonia)
• Gastrointestinal bleeding
• Constipation
• Dehydration or over-diuresis
• Electrolyte disturbances (hyponatremia, hypokalemia)
• Sedating medications (benzodiazepines, opiates)
• Clinical rule: Treat the precipitant first; failure to do so is a leading cause of persistent or refractory HE

Pharmacologic Management

• Lactulose (First-line):

- Mechanism: Colonic acidification → converts NH₃ to NH₄⁺ (non-absorbable); cathartic effect promotes ammonia excretion

- Target: 2–3 soft bowel movements per day

- Dose must be titrated to effect — not fixed

- Continued long-term for secondary prophylaxis

- Risks: Overdosing → diarrhea → dehydration/electrolyte disturbances → may worsen HE

• Rifaximin (Second-line / Add-on):

- Used as adjunct to lactulose, not monotherapy

- Mechanism: Alters gut microbiome, reduces ammonia-producing bacteria

- Indication: Secondary prophylaxis after overt HE, particularly with breakthrough episodes despite optimized lactulose

- Associated with reduced recurrence, improved quality of life, and fewer hospitalizations

Refractory HE — Evaluation and Advanced Management

• Common causes of refractory disease:

- Large spontaneous portosystemic shunts (SPSS)

- Advanced hepatic dysfunction/reduced hepatic reserve

- Non-adherence to lactulose

- Occult/ongoing precipitants (low-grade infection, intermittent GI bleeding, electrolyte abnormalities)

• Imaging:

- CT or MRI with venous phase recommended in recurrent/refractory HE

- Purpose: Identify large SPSS as an anatomically actionable cause

• Shunt Embolization:

- Indicated in carefully selected patients with:

- Large SPSS on imaging

- Preserved liver function

- Recurrent HE despite optimized medical therapy

- Associated with significant reduction in overt HE episodes

- Caution: Eliminates shunt → may increase portal venous pressure → risk of worsening ascites or variceal bleeding

- Must be performed at experienced centers in coordination with hepatology/transplant teams

- May serve as a bridge to liver transplantation

Nutritional Principles

• Protein restriction is NOT recommended