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"acute liver failure" management guidelines
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Here is a comprehensive overview of Acute Liver Failure (ALF) Treatment Guidelines:
Definition
ALF = severe liver injury (elevated transaminases) + hepatic encephalopathy (HE) + coagulopathy (INR >1.5) in a patient without pre-existing liver disease.
Subtypes by time from symptom onset to encephalopathy:
- Hyperacute: <7 days (most likely to develop cerebral edema)
- Acute: 7–21 days
- Subacute: 21 days – 26 weeks (more likely to present with portal hypertension)
Common Causes
| Etiology | Notes |
|---|---|
| Acetaminophen overdose | #1 cause in US/Western Europe (~40–50%) |
| Idiosyncratic drug-induced liver injury | ~13% |
| Hepatitis B | ~6% |
| Ischemic hepatitis | ~6% |
| Autoimmune hepatitis | ~4% |
| Hepatitis A | ~4% |
| Wilson's disease, Budd-Chiari, pregnancy | Less common |
| Indeterminate | ~17% |
Immediate Management
1. Transfer & Monitoring
- Immediately transfer to a liver transplant center — deterioration can be rapid
- Admit to ICU for continuous monitoring
- Grade 3–4 HE → intubate for airway protection
2. Neurological / Cerebral Edema Management
Cerebral edema is the leading cause of death in ALF (occurs in ~80% of grade 4 HE patients).
| Intervention | Details |
|---|---|
| Head elevation | 30° |
| Avoid fever | Maintain normothermia |
| Euglycemia | Maintain normal blood glucose |
| Hypertonic saline | Goal serum Na 140–145 mmol/L; use hypertonic saline (200 mL 2.7% or 20 mL 30%) for clinical ICP elevation |
| Mannitol | 150 mL of 20% over 20 min for acute ICP crisis |
| Hyperventilation | Target PaCO₂ 25–30 mmHg acutely (promotes cerebral vasoconstriction) |
| Minimize stimulation | Sedation/paralysis to prevent ICP spikes |
⚠️ Lactulose and rifaximin are NOT shown to benefit ALF (unlike in cirrhosis). Focus is on reducing ICP, not ammonia via gut.
3. Ammonia & Renal Support
- Arterial ammonia correlates with HE severity in ALF (unlike chronic liver disease)
- Ammonia >200 μmol/L → high risk of cerebral edema and intracranial hypertension
- Continuous renal replacement therapy (CRRT) is effective for rapid ammonia clearance
4. ICP Monitoring
- Invasive ICP monitors are controversial due to bleeding risk (coagulopathy)
- If used: goal ICP <20–25 mmHg; cerebral perfusion pressure >50 mmHg
- Non-invasive alternatives: transcranial Doppler ultrasound, jugular venous oximetry
- CT head: insensitive early, but useful to exclude intracranial hemorrhage/herniation. If herniation is evident on CT → transplant likely contraindicated
Deciding on Liver Transplantation
King's College Criteria (most widely used; PPV 80–100%)
Acetaminophen cases:
- Arterial pH <7.3 after resuscitation, OR
- INR >6.5 AND serum creatinine >3.4 mg/dL AND grade III–IV encephalopathy
Non-acetaminophen cases:
- INR >6.5, OR
- Any 3 of the following:
- INR >3.5
- Bilirubin >17.6 mg/dL
- Age <10 or >40 years
- Drug toxicity as cause
- Time from jaundice onset to encephalopathy >7 days
MELD score can also predict hospital mortality; King's College performs better for acetaminophen ALF.
Transplant outcomes: ~84% 1-year survival in the US (though still inferior to spontaneous recovery).
Progression to grade II HE is often used as a trigger to begin transplant workup. Act fast — this is time-critical.
Extracorporeal Liver Support (ELS)
Used as a bridge to transplant or spontaneous recovery at select centers:
| System | Mechanism | Evidence |
|---|---|---|
| MARS | Albumin dialysis | No mortality benefit in RCTs; may improve HE symptoms |
| Prometheus | Plasma separation + adsorption + dialysis | Safe; no survival benefit shown in ACLF |
| SPAD | High-flux albumin membrane dialysis | No impact on survival shown so far |
| High-volume plasma exchange (HVP) | Removes toxins, replenishes coagulation factors | Small studies suggest survival benefit; more research needed |
Specific Cause Management
- Acetaminophen: N-acetylcysteine (NAC) — the definitive antidote; also has benefit beyond the standard treatment window
- Autoimmune hepatitis: corticosteroids (if no sepsis)
- Wilson's disease: urgent transplant evaluation
- Hepatitis B: antiviral therapy (e.g., tenofovir)
- Budd-Chiari: anticoagulation ± TIPS
Sources: Current Surgical Therapy 14e, p. 460–461, 493; Sabiston Textbook of Surgery, p. 1069
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