Hepatic Encephalopathy Grading (West Haven)

Hepatic encephalopathy (HE) is a spectrum of neuropsychiatric abnormalities occurring in patients with significant liver dysfunction, caused by the accumulation of neurotoxic substances — most notably ammonia — that the failing liver cannot adequately clear or metabolise. It is classified as covert (minimal or grade 1) or overt (grades 2–4), and can be episodic, recurrent, or persistent depending on the clinical course. The West Haven Criteria (WHC) are the most widely used grading system for classifying the severity of hepatic encephalopathy: Grade 0 has no clinical evidence of HE but subtle neuropsychiatric changes may be detected with psychometric testing (referred to as minimal HE or covert HE); Grade 1 involves trivial lack of awareness, shortened attention span, altered sleep pattern, and mild personality changes; Grade 2 is characterised by lethargy, disorientation, asterixis (flapping tremor), and obvious personality change; Grade 3 involves somnolence, gross disorientation, bizarre behaviour, and asterixis may be present; Grade 4 is coma with or without response to painful stimuli. Hepatic encephalopathy is a major complication of cirrhosis, occurring in up to 30–45% of patients with cirrhosis over their lifetime, and is associated with significant morbidity, impaired quality of life, and increased mortality. The most common precipitating factors include infections (especially spontaneous bacterial peritonitis), gastrointestinal bleeding, constipation, electrolyte disturbances, medications (sedatives, opioids), and non-adherence to lactulose therapy. Treatment involves identifying and reversing precipitating factors, administering lactulose to reduce ammonia production and absorption, and using rifaximin as secondary prophylaxis to prevent recurrence.

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1. 1Assess orientation and cognition: ask the patient for their name, current date, location, and year. Disorientation to time (day, month, year) characterises Grade 2; disorientation to place or person escalates towards Grade 3.
2. 2Assess level of consciousness: full alertness (Grade 0–1), somnolence but rousable (Grade 2–3), or unarousable (Grade 4 — coma).
3. 3Test for asterixis (flapping tremor): ask the patient to extend arms with dorsiflexed wrists for 15–30 seconds. Rhythmic flapping movements indicate Grade 2–3 HE. Note: asterixis cannot be assessed in comatose patients (Grade 4).
4. 4Assess personality and behaviour: mild changes such as euphoria, irritability, or minor sleep disturbances suggest Grade 1; overt behavioural change, disinhibition, or aggression suggests Grade 2; bizarre/gross personality disturbance points to Grade 3.
5. 5For covert HE (Grade 0–1), standard bedside assessment is insensitive — validated psychometric tools (e.g., the Psychometric Hepatic Encephalopathy Score [PHES], Stroop test, or CFF) are needed to detect minimal HE.
6. 6Identify and treat precipitating factors: send blood cultures, urinalysis, ascitic fluid analysis (SBP), check electrolytes, renal function, blood glucose, and review all medications. Constipation, infection, and GI bleeding account for most episodes.
7. 7Initiate treatment: lactulose 30–45 mL orally up to 3–4 times daily, titrating to produce 2–3 soft stools per day; for secondary prophylaxis (especially after first overt episode), add rifaximin 550 mg twice daily.

• !Relying solely on serum ammonia levels to diagnose or grade HE — ammonia correlates poorly with grade and should not replace clinical assessment using the West Haven criteria.
• !Over-sedating HE patients with benzodiazepines (except for alcohol withdrawal), which dramatically worsens HE — benzodiazepines are a common precipitant and should be avoided.
• !Failing to identify and treat the underlying precipitant before or alongside lactulose therapy — treating HE without addressing the precipitant (e.g., unrecognised SBP) leads to treatment failure.
• !Titrating lactulose to more than 3 stools per day, causing diarrhoea, electrolyte disturbance, and dehydration — which can paradoxically worsen HE.
• !Attributing altered consciousness in a cirrhotic patient to HE without ruling out other causes: subdural haematoma (from falls and coagulopathy), hypoglycaemia, sepsis, Wernicke encephalopathy, or benzodiazepine/opioid accumulation.
• !Not starting rifaximin after the first episode of overt HE — EASL/AASLD guidelines recommend rifaximin 550 mg twice daily as secondary prophylaxis following any overt HE episode.