Fulminant Hepatic Failure
27/10/10
FANZCA Part II Notes
SP Liver Transplantation Notes
PY Mindmaps
Irwine and Rippe
= rapid onset of encephalopathy in conjunction with hepatic synthetic failure.
CAUSES (DAVES)
Drugs – paracetamol, idiosyncratic, illicit, herbal/alternative (amanita mushroom), halothane
Alcohol –
Viruses – HAV, HBV, HCV, CMV, EBV, HSV,
Extras – acute fatty liver of pregnancy, HELLP, toxins, ischaemic necrosis, vascular, metabolic,
autoimmune, Wilson’s disease, Budd-Chiari, post hepatic surgery, idiopathic
Sepsis
HEPATIC ENCEPHALOPATHY
- sleep disturbance
- asterixis
- hyper-reflexic
- can be hemiplegic
- precipitating factor: GIH, infection, hypokalaemia, sedatives, increased protein intake,
progressive hepatic dysfunction, renal failure
- types: A = acute liver failure, B = presence of portocaval shunting, C = in context of cirrhosis
- grade I -> IV: mildly drowsible but rousable and coherent -> responding to pain/unconscious
INVESTIGATIONS
- elevated ammonia (not required to make diagnosis of encephalopathy)
- urine and serum toxicology screen
- hepatitis serologies
- ceruloplasmin
- antinuclear antibodies
- smooth-muscle antibiodies
- serum protein electrophoresis
- CMV and EBV serology
- serum phosphate: decrease suggestive of hepatocyte recovery and regeneration -> good
prognostic marker
Jeremy Fernando (2011)
MANAGEMENT
Resuscitation
A – intubated if unresponsive from encephalopathy (RSI to prevent aspiration)
B – often have respiratory failure from pleural effusions and may have aspirated requiring
mechanical ventilation
C – fluid maintenance, often have a hyperdynamic circulation, vasoactive medication
D – monitoring for intra-cranial hypertension: ICP bolt, mannitol, propofol, thiopentone,
moderate hypothermia (32-33 C), hypertonic saline
Once stabilized early consultation with Liver Transplant Centre
Vigilant monitoring for infection (bacterial, fungal)
Treatment
Specific
- paracetamol OD: N-acetylcysteine 150mg/kg LD, 50mg/kg over 4 hours, 100mg/kg over 16
hours
- Amanita poisoning: penicillin
- acute fatty liver of pregnancy: delivery of infant and placenta
- Wilson’s disease: zinc and trientine therapy, apheresis
- Acute Budd-Chiari: TIPS, surgical decompression, thrombolysis -> transplantation
- HSV: acyclovir
- ischaemic: restore circulation to liver
- encephalopathy: lactulose -> increases ammonia elimination, metronidazole -> alter gut flora to
decrease ammonia production, flumazenil (controversial)
- coagulopathy: only treat with FFP if bleeding or prior to procedures, FVIIa safe and effective
- NAC: continue until encephalopathy resolves
- TIPS procedure (decrease portal hypertension and ascites)
- short-term extracorporeal hepatic support (MARS):
- ‘liver dialysis’
- Molecular Absorbent Recirculating System: detoxification method based on albumin
dialysis
- can be used as a bridge to transplantation (experimental)
- requires two separate dialysis circuits
- limited case series shows some benefit in paracetamol OD
- contraindicated in active bleeding and coagulopathy
- expensive
- not available outside specialist centres.
CRITERIA FOR TRANSPLANTATION (King’s College Criteria)
Paracetamol induced fulminant hepatic failure
Jeremy Fernando (2011)
- pH < 7.3 or INR > 6.5 (PT > 100s)
+
- Cr > 300micromol/L
+
- grade III or IV encephalopathy
Non-paracetamol induced fulminant hepatic failure
- INR > 6.5 (PT > 100s) or any 3 of the following variables:
(1)
(2)
(3)
(4)
(5)
age < 10 or > 40 yrs
aetiology – non A, non B hepatitis, halothane hepatitis, idiosyncratic drug reactions
duration of jaundice before encephalopathy > 7 days
INR > 3.5 (PT > 50s)
bilirubin > 300micromol/L
General
-
electrolyte balance (hypokalaemia, hyponatraemia, hypophosphataemia)
Na+ restriction + diuretics -> decreases ascites
frequent glucose monitoring (hypoglycaemia)
nutrition (amino acids, lipids, glucose, essential elements)
renal failure is common (especially in paracetamol OD -> direct renal toxic effects)
feed
Disposition
- management in ICU
- early discussion with liver transplant unit (prior to reversal of coagulopathy)
- discussion with family (high mortality)
COMPLICATIONS
- cerebral oedema and herniation
- coagulopathy
- GI bleed
- sepsis
- renal failure
- hypoglycaemia
- electrolyte abnormalities
- respiratory failure: impaired ventilation c/o coma, pleural effusions, ARDS, intra-pulmonary
shunts, aspiration, sepsis
CONTROVERSIAL ISSUES
- targeted CPP management with insertion of an ICP monitor
- MARS therapy
- use of FVIIa
Jeremy Fernando (2011)