HEPATIC ENCEPHALOPATHY

✓ Medically ReviewedDISEASEID: MDBT0115🚨 TRIAGE: URGENTICD-10: K72.90

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Definition

CLINICAL DEFINITION

Hepatic encephalopathy is brain dysfunction from liver failure. Failure means poor toxin clearing with blood bypassing the liver. Ammonia (gut waste chemical) and inflammation disturb brain signals. It spans poor attention and confusion to stupor (deep sleepiness) and coma (unresponsiveness). Diagnosis needs liver disease or shunt (bypass vessel) with other brain causes excluded.

IN PLAIN ENGLISH

Liver cleans blood. When liver fails, waste builds up. Waste reaches brain. It causes confusion or sleepiness. Doctors treat triggers and lower waste.

COMMON MISCONCEPTION / WHAT IT DOES NOT MEAN

Hepatic encephalopathy is not dementia (slow memory loss disease) alone. It is not delirium (sudden confusion) from infection alone without liver failure. It is not stroke (blocked brain blood flow) with focal weakness. It is not intoxication (drug or alcohol effect) alone, though sedatives (sleepy drugs) can worsen it. Diagnosis needs liver failure or shunt (bypass vessel) with mimics excluded.

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Word Breakdown

hepat-encephal-

=liver and brain

-pathy

=disease condition

Literal Meaning: liver brain disease

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Abbreviations

HE=Hepatic encephalopathy - brain change from liver failure

CHE=Covert hepatic encephalopathy - hidden mild form found only on testing

OHE=Overt hepatic encephalopathy - visible confusion or coma

TIPS=Transjugular intrahepatic portosystemic shunt - liver bypass channel made through neck vein

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Synonyms & Variants

Portosystemic encephalopathy›Hepatic coma›Portal-systemic encephalopathy›

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Category-Specific Context

Hepatic encephalopathy is a Disease because it is a syndrome (linked pattern) with causes and course. It is not a single Symptom (patient complaint) or Sign (exam finding). It marks decompensated liver failure (failing filter function) with brain effects. Care targets liver, gut and triggers (worsening causes) rather than brain alone. It sits under liver failure with coma as its severe end.

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Clinical Context & Usage

CLINICAL SETTINGS

Emergency DepartmentAcute Medical UnitGastroenterology WardIntensive Care Unit for Severe CasesLiver Clinic for Covert Disease

USAGE & DOCUMENTATION NOTES

Use hepatic encephalopathy for brain change linked to liver failure or shunt (bypass vessel). Record grade, orientation, asterixis (flapping hand tremor) and suspected triggers. Distinguish overt disease (visible confusion) from covert disease (hidden deficits on testing). Reassess after trigger care because findings can improve quickly.

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Primary Causes & Pathophysiology

PATHOPHYSIOLOGY

Liver failure and shunting (bypass flow) let ammonia (gut waste gas) reach the brain. Ammonia injures astrocytes (brain support cells) and disturbs nerve signals. Inflammation (immune activation) and oxidative stress (cell damage from reactive molecules) worsen vessel leak. Gut dysbiosis (imbalanced bowel germs) and constipation (slow stool passage) raise toxin load. Together these cloud thinking and lower alertness.

PRIMARY CAUSES

Cirrhosis with portal hypertension (scarred liver with high vein pressure)

Scarring raises pressure and shunts blood around the liver so toxins reach the brain

Acute liver failure (sudden severe liver loss)

Abrupt loss of clearing floods the brain with ammonia and inflammatory signals

Large spontaneous or TIPS shunt (bypass channel)

Bypass diverts portal blood past the liver and cuts detoxification

Gastrointestinal bleeding in cirrhosis (blood loss into gut)

Blood protein load raises gut ammonia production and worsens brain change

Infection including spontaneous bacterial peritonitis (belly fluid infection)

Immune activation with fever raises brain sensitivity and toxin effects

Constipation with renal failure and electrolyte shifts (slow stools with salt upset)

Slow transit raises absorption while dehydration and low sodium lower brain reserve

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Drug-Induced Causes

💊 Benzodiazepines such as diazepam and midazolam ↗

Mechanism: Boost inhibitory brain signals and depress alertness in liver failure

→ Avoid and stop with monitoring, seek specialist advice for supervised withdrawal

💊 Opioids such as morphine and codeine ↗

Mechanism: Depress consciousness and slow gut transit raising toxin absorption

→ Avoid when possible, use safer pain options with breathing and bowel review

💊 Diuretics with overuse such as furosemide and spironolactone ↗

Mechanism: Cause dehydration with low sodium and potassium shifts that trigger confusion

→ Review dose, correct fluids and salts under supervision with alertness checks

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Epidemiology

Prevalence:Hepatic encephalopathy is common in cirrhosis with decompensation (advanced failure). Covert impairment (hidden thinking change) is frequent and often missed without testing. Risk rises with liver severity and shunt size. Recurrence is frequent after a first overt episode without prevention.

Age Group:Most cases occur in middle-aged and older adults with cirrhosis. Younger adults are affected with acute liver failure or large shunts. Children are rarely affected except with inborn liver disease or shunts. Older brains may show deficits at milder toxin levels.

Geographic Distribution:Hepatic encephalopathy occurs worldwide wherever cirrhosis and liver failure occur. Patterns follow alcohol use, viral hepatitis and fatty liver trends. Detection tracks access to liver testing and shunt care. No climate restriction applies.

Red Flags & Triage ★

TRIAGE LEVEL

🚨 URGENT

DO NOT MISS — LIFE-THREATENING PRESENTATIONS

Gastrointestinal bleeding as precipitant
Infection including spontaneous bacterial peritonitis
Acute kidney injury with salt shifts
Cerebral oedema in acute liver failure
Drug sedation with constipation

URGENT EVALUATION TRIGGERS

Worsening consciousness or new coma
Fever with suspected infection
Vomiting blood or black stools
Severe agitation or seizures
Breathing difficulty with aspiration concern

Contraindications & Precautions

CONTRAINDICATIONS

Do not use sedatives that depress consciousness in encephalopathy
Do not restrict protein severely long term because it worsens muscle loss
Do not create large shunts without weighing brain fog risk
Do not delay trigger care for extensive testing when overt confusion is present

SPECIAL PRECAUTIONS

Monitor consciousness with asterixis (hand flap) during any acute illness
Correct constipation (slow stools) and dehydration (low body water) promptly
Review sedatives (sleep aids) and diuretics (water tablets) at each episode
Counsel on driving and falls when covert deficits persist
Arrange hepatology review with prevention planning after any overt episode

Complications

DOWNSTREAM CLINICAL COMPLICATIONS

Aspiration with respiratory failure from depressed consciousness
Falls with fractures from confusion and unsteady gait
Cerebral oedema with high pressure in acute liver failure
Recurrent hospital admission with loss of independence
Persistent covert deficits with unsafe driving and poor work function

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Confused With (LASA & DDx) ★

LEXICAL (LASA) — SIMILAR NAMES

Wernicke encephalopathy

Both cause confusion in alcohol use but Wernicke is thiamine lack needing vitamin care

Uraemic encephalopathy

Both cause flap and confusion but uraemic means kidney failure waste buildup, not liver failure

Hyponatraemic encephalopathy

Low sodium mimics liver fog but means salt imbalance needing sodium care, not toxin load

CLINICAL DIFFERENTIAL DIAGNOSES (DDx)

Alcohol withdrawal syndrome

Key Distinguishing Feature: Tremor with agitation and sweats plus fast pulse without liver trigger or flap

Ischaemic stroke

Key Distinguishing Feature: Sudden focal weakness or speech loss with imaging lesion and stable liver course

Subdural haematoma

Key Distinguishing Feature: Head injury history with focal signs and one-sided weakness

Hyponatraemia

Key Distinguishing Feature: Low salt on labs improving with salt correction without liver trigger

Sepsis delirium

Key Distinguishing Feature: Fever with infective source without chronic liver marks or flap

Hypoglycaemia

Key Distinguishing Feature: Low glucose with sweats that reverses fast with dextrose (sugar infusion)

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Clinical Pearls

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Check orientation with asterixis (flapping tremor) in every cirrhosis patient with confusion. Grade severity and record triggers at once.

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Search for bleeding with infection as reversible drivers before blaming liver alone. Test urine, blood and belly fluid early.

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Give lactulose (gut sugar that clears toxins) titrated to 2 to 3 soft stools daily per protocol. Add rifaximin (gut antibiotic) after recurrence per guidance.

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Avoid sedatives and correct constipation with dehydration early. Review diuretics (water tablets) and salts at each visit.

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Counsel families on driving with falls even with covert disease. Arrange hepatology follow-up with prevention plan after any overt episode.

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Example Usage & SOAP

CLINICAL SENTENCE

""58-year-old man with cirrhosis and flap has overt hepatic encephalopathy from constipation.""

IN A SOAP NOTE

S: 58-year-old man with cirrhosis reports 2 days confusion with daytime sleepiness and constipation, no head injury. O: Temp 37.0C, BP 110/70, HR 92, RR 18, SpO2 97 percent on air, drowsy but rousable, disoriented to time, flap present, jaundice with belly fluid. A: Overt hepatic encephalopathy likely triggered by constipation with possible infection. P: Trigger hunt with labs and cultures, gut-targeted therapy with monitoring, airway watch, avoid sedatives, correct fluids and arrange liver review.

DIFFERENTIAL DIAGNOSIS CONTEXT

Confusion with flap in cirrhosis favours hepatic encephalopathy over psychiatric disease. Tremor with sweats and agitation favours alcohol withdrawal. Focal weakness favours stroke (brain vessel block). Low salt without liver trigger favours hyponatraemia. Check liver course with ammonia, salts and infection screen.

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Classifications & Scoring

GRADING SYSTEM

West Haven Criteria

Bedside grades from inattention through disorientation and stupor to coma. Guides team talk and trigger search at each grade.

STAGING SCALE

ISHEN covert overt classification

Stages disease as covert hidden deficits versus overt visible confusion. Separates minimal and grade one from higher grades for testing and follow-up.

SCORING TOOL

Psychometric Hepatic Encephalopathy Score

Paper tasks testing attention and speed against healthy norms. Detects covert deficits and tracks change in clinic.

SCORING TOOL

Stroop EncephalApp test

Mobile test of response control and processing speed. Screens for covert impairment and guides driving counsel.

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Prognosis

SHORT-TERM OUTCOME

Mild overt episodes often improve within days after trigger care. Severe coma or acute failure carries high early risk without transplant. Delay with missed bleeding or infection worsens course. Early airway protection with trigger hunt improves safety.

LONG-TERM PROGNOSIS

Long term outlook follows liver function and transplant candidacy (suitability for new liver). Recurrent overt disease signals higher readmission and death risk. Persistent covert deficits impair driving, work and daily life. Transplant often greatly improves chronic brain change when liver recovers.

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References & Coding

ICD-10 DIAGNOSTIC CODE

K72.90

LITERATURE CITATIONS & GUIDELINES

[1]WHO ICD-10 K72 Hepatic failure

[2]EASL Clinical Practice Guidelines on hepatic encephalopathy

[3]AASLD Practice Guidance on hepatic encephalopathy

[4]Harrison's Principles of Internal Medicine liver disorders

MEDICAL DISCLAIMER — This content is intended for educational purposes and qualified healthcare professionals only. Always refer to current clinical diagnostic criteria, institutional protocols, and official guidelines. Medobo is not responsible for clinical decisions made based on this content.