Hepatic Encephalopathy

Hepatic encephalopathy (HE) is a common and potentially reversible cause of confusion in patients with cirrhosis.
It is frequently missed, underestimated, or attributed to “baseline behaviour”, which can lead to serious harm.

This guide focuses on practical recognition and management on the ward and on-call.

What is hepatic encephalopathy?

Hepatic encephalopathy is brain dysfunction caused by liver failure, usually due to the accumulation of toxins (such as ammonia) that the liver can no longer clear.

In simple terms:

The liver is failing, and the brain is affected.

How does it present?

Presentation is often subtle, especially early on.

Common features:

  • Confusion
  • Drowsiness
  • Personality or behaviour change
  • Poor concentration
  • Reversed sleep pattern
  • Slurred speech
  • Asterixis (flapping tremor)
  • Reduced GCS in severe cases

Red flags:

  • Marked drowsiness
  • Reduced responsiveness
  • GCS dropping
  • Inability to protect airway

Never assume confusion in a cirrhotic patient is “normal”.

Common causes (think practically)

HE is usually triggered by something.

Common triggers on the ward:

  • Infection (especially SBP, UTI, chest infection)
  • Constipation
  • GI bleeding
  • Dehydration
  • Electrolyte disturbance (especially hyponatraemia, hypokalaemia)
  • Over-diuresis
  • Alcohol
  • Sedatives / opioids

If you treat HE without looking for a trigger, it will recur.

On the ward, always ask

What has precipitated this episode?

Then actively look for:

  • Infection
  • Constipation
  • Bleeding
  • AKI
  • New medications

Fixing the trigger is as important as giving lactulose.

First priority = Assess severity and safety

Before jumping to treatment:

  • Assess GCS
  • Can the patient protect their airway?
  • Are they safe to remain on the ward?
  • Are they eating and drinking?
  • Do they need HDU/ICU review?

Severe HE can be life-threatening.

Immediate management on the ward (what juniors should actually do)

If you’re called to review a cirrhotic patient with confusion:

Do early:

  • A–E assessment
  • Bloods: FBC, U&E, LFTs, INR, CRP
  • Glucose (always)
  • Cultures if infection suspected
  • Urinalysis
  • CXR if respiratory symptoms
  • Consider ascitic tap if ascites present

Start treatment:

  • Lactulose (aim for 2–3 soft stools per day)
  • Consider rifaximin if recurrent or severe (usually after senior input)
  • Correct electrolytes
  • Treat constipation
  • Stop sedating medications where possible

Ammonia levels:

  • Can support the diagnosis
  • But do not rely on ammonia alone to make decisions

When to escalate

Escalate urgently if:

  • GCS reduced
  • Patient is very drowsy
  • Airway concerns
  • Rapid deterioration
  • Sepsis suspected
  • AKI present
  • NEWS ≥5
  • Concerned nursing staff

These patients may need:

  • Gastro registrar input
  • HDU/ICU review
  • Airway protection

Never leave a severely encephalopathic patient overnight without senior review.

Common mistakes juniors make

  • Attributing confusion to “baseline”
  • Giving lactulose but not treating the trigger
  • Forgetting to check for infection
  • Over-sedating agitated patients
  • Not escalating reduced GCS
  • Relying too heavily on ammonia levels

HE is a clinical diagnosis, not a lab result.

Take-home concept

Hepatic encephalopathy is not just confusion.
It is a sign of decompensation that demands you find the trigger, treat early, and escalate appropriately.