Liver: Liver Failure

Liver Failure

Acute Liver Failure (Fulminant Hepatic Failure)

  • Definition: Acute Liver Injury with Hepatic Encephalopathy & INR ≥ 1.5
    • Onset < 26 Weeks
  • Most Common Causes:
    • Acetaminophen Toxicity (Most Common in US)
    • Viral Hepatitis
  • Most Common Cause of Death: Cerebral Edema Causing Intracranial HTN
    • Outcomes Determined by: Encephalopathy Grade
  • Tx: Treat Underlying Cause & Treat Complications
    • Consider Liver TXP if Unlikely to Recover Spontaneously
    • All Should Immediately Be Referred to a Liver Transplant Center

Cirrhosis

  • Definition: Hepatic Fibrosis Causing Impaired Liver Function
  • Most Common Causes:
    • Chronic Hepatitis
    • Alcoholic Liver Disease
    • Nonalcoholic Fatty Liver Disease
  • Best Indicator of Synthetic Function: PT
  • Dx: Liver Bx
    • Not Necessary if Clinical Presentation, Labs & CT Strongly Suggests
  • Tx: Prevent Further Injury & Treat Complications
    • Definitive Treatment: Liver TXP

Complications

King’s College Criteria

  • Early Indices to Predict Poor Prognosis in Acute Liver Failure
  • Used to Determine the Need for Liver Transplant
  • Tylenol-Induced ALF:
    • pH < 7.3
    • All 3:
      • INR > 6.5
      • Cr > 3.4 mg/dL (300 micro-mol/L)
      • Encephalopathy (Grade III/IV)
  • Non-Tylenol-Induced ALF:
    • INR > 6.5
    • ≥ 3 Of:
      • Age < 10 or > 40
      • Bilirubin > 17.5 mg/dL (300 micro-mol/L)
      • Jaundice Onset > 7 Days Before Development of Encephalopathy
      • INR > 3.5
      • Unfavorable Etiology (Wilson Disease, Drug-Induced, Seronegative Hepatitis)

Hepatic Encephalopathy

  • Reversible Impairment of Brain Function from Liver Failure
  • Cause: Increased Ammonia Production from Nitrogen in Gut Lumen
  • Grade:
    • Grade I: Mild Confusion & Changes in Behavior
    • Grade II: Moderate Confusion & Lethargy
    • Grade III: Severe Confusion & Incoherent
    • Grace IV: Coma
  • Asterixis – Flapping Motion of Hands When Outstretched & Dorsiflexed
  • Tx: Lactulose (Cathartic Prevents Ammonia/NH3 Uptake in Gut)

Other Complications

Liver Failure Scores

Child-Pugh Score

  • Assess Prognosis of Cirrhosis & Predict Mortality
  • Criteria: Mn
Criteria+1+2+3
Albumin> 3.5 g/dL2.8-3.5 g/dL< 2.8 mg/dL
Total Bilirubin< 2 mg/dL2-3 mg/dL> 3 mg/dL
INR< 1.71.7-2.2> 2.2
AscitesAbsentSlightModerate-Severe
EncephalopathyNoneGrade I-IIGrade III-IV
  • Classes:
    • Class A: 3-6 Points
    • Class B: 7-9 Points
    • Class C: 10-15 Points

MELD (Model for End-Stage Liver Disease) Score

  • Assess Severity of End-Stage Liver Disease & Predict Mortality
  • Original Criteria: Mn
    • Creatinine
    • INR
    • Total Bilirubin
  • New (2016) Criteria:
    • Creatinine
    • INR
    • Total Bilirubin
    • Sodium
  • Additional Points Awarded for Hepatocellular Carcinoma

Mnemonics

Child-Pugh Score

  • Children Recite “A-B-C-D-E”
    • Albumin
    • Bilirubin (Total)
    • Coags (PT/INR)
    • Distention (Ascites)
    • Encephalopathy

MELD (Model for End-Stage Liver Disease) Score

  • “CrIB” (Old) & “CrIBS” (New)
    • Creatinine
    • INR
    • Bilirubin (Total)
    • Sodium