UW revision acute liver failure , HE 03-05 (2) Flashcards
TRIAD acute liver failure?
Hepatic encephalopathy
Elevated transaminases
Impaired synthetic liver function (INR >= 1,5)
Very important, that acute liver failure should occur in patients with normal liver - NO CIRRHOSIS OR UNDERLYING LIVER DISEASE
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What differentiates acute liver failure from acute hepatitis?
presence of hepatic encephalopathy
ALF table. Etiology?
Viral hepatitis (HSV, CMV, HAV, B, C, D)
Drug toxicity (paracetamol, idiosyncratic)
Ischemia (shock liver, Budd-Chiari syndrome)
Autoimmune hepatitis
Wilson disease
Malignant infiltration
ALF table. CP?
General symptoms - fatigue, lethargy, anorexia, nausea)
RUQ pain
Pruritus and jaundice due to hyperbilirubinemia
Renal insuff.
Thrombocytopenia
Hypoglycemia
ALF table. Diagnostic requirements? 3
Severe acute liver injury (AST and ALT usually > 1000)
Signs of hepatic encephalopathy (confusion, asterixis)
Synthetic liver dysfunction
Chronic HBV carriers, typically remain asymptomatic without evidence of underlying liver disease (eg fibrosis). In this case superinfection (HBV + HDV) –> carries high risk of ALF.
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Urine output in ALF?
decreased (due to intravascular volume depletion and decreased renal perfusion)
BUT NOT A PART OF ALF TRIAD DIAGNOSTICS
Portal venous pressure in ALF?
Increased (due to incr. resistance to blood flow through the inflamed liver)
BUT NOT A PART OF ALF TRIAD DIAGNOSTICS
Bilirubin in ALF?
Severe hyperbilirubinemia is common
BUT NOT A PART OF ALF TRIAD DIAGNOSTICS
What virus cause cirrhosis?
HCV
What viruses cause ALF?
HAV, HBV, HDV, HEV
Renal failure common due to direct renal tubular toxicity (from acetaminophen)
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HE table. Precipitating factors?
Drugs (sedatives, narcotics)
Hypovolemia (eg diarrhea)
Electrolyte changes (eg hypokalemia)
Incr. nitrogen load (eg GI bleeding)
Infection (pneumonia, UTI, SBP)
Portosystemic shunting (eg TIPS)
HE table. CP?
Asterixis, ataxia, altered mental status, sleep pattern changes
HE table. Tx? 2
- Correct precipitating factors (eg fluids, antibiotics)
- Decr. blood ammonia concentration (lactulose, RIFAXIMIN)
HE. ABs?
kinda Tx of underlying cause (eg pneumonia), bet turi but sisteminiai infekcijos pozymiai (temp, leu, tachy)
wernicke vs HE?
In wernicke: Altered mental status, ataxia, NYSTAGMUS, NO ASTERIXIS.
in HE: altered mental status, sleep pattern changes, ataxia, ASTERIXIS
Dont give high-proteins cirrhosis –> can precipitate HE by increasing ammonia levels.
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How hypokalemia can trigger HE?
Hypokalemia: exacerbate HE as resultant intracellular acidosis (K out, H in) causes increased NH3 production (glutamine conversion) in renal tubular cells.
How metabolic alkalosis can trigger HE?
Metabolic alkalosis: exacerbate HE as it promotes conversion of ammonium (NH4+) [cannot enter CNS] to NH3 [can enter CNS].
Proteins in cirrhosis?
Dont give high-protein diet - it cant precipitate HE
BUT also, these patients are malnourished, therefore do no give protein-free diet.
Protein restriction is generally for those with TIPS
When give neomycin in HE?
Used to Tx HE in patients unresponsive to lactulose or cannot tolerate rifaximin.
When is performed TIPS?
When ascites does not responds to medical Tx (eg diuretics) OR has ungoing active or recurrent variceal bleeding even after appropriate treatment with upper endoscopy. TIPS assoc. with HE in up to 35 proc. patients due to (NH3-rich) blood bypassing the liver.