| ID | 52 |
|---|---|
| Name | ACUTE (FULMINANT) HEPATIC FAILURE (FHF) |
| Cause | Causes: Severe liver damage by any cause, can produce acute liver failure. Such as: 1. Acute viral hepatitis (A,B,C & E)- about 70% (up to 50% due to hepatitis B) 2. Drugs- analgesics e.g paracetmol, anaesthetics e.g halothane, antiepileptics e.g valproate and MAOIs e.g imipramine,. 3. Toxins- mushrooms (amanita phalloides) poisoning, halohydrocarbon. 4. Misc: Wilsons disease, Reye’s syndrome, Budd-chiari syndrome, Fatty liver of pregnancy, following shock, malignant disease of the liver, hyper or hypothermia etc. 5. Unknown cause- often labelled as having non-A-E viral hepatitis or cryptogenic acute liver failure. |
| Signs Symptoms | |
| Diagnosis | |
| Investigations | Investigation: All investigations to be done as for jaundice (stated above) Management: There is no specific treatment, only supportive management is given. If available, patients should be transferred and treated in a high-dependency or intensive care unit as soon as progressive prolongation of the prothrombin time occurs or hepatic encephalopathy is developed 1. For encephalopathy: i. Avoid nitrogenous (protein) food. ii. Avoid sedative drugs, but a smallest possible dose of short acting benzodiazepine (e.g midazolum) can be given for restlessness & excitement, (in that case, antagonist like flumazenil must be available). 2. For cerebral oedema & raised intracranial pressure: Mannitol 20% 100-200ml (or Igm/kg) should be infused i.v rapidly over half an hour. The same can be repeated if necessary. 3. Nutrition: Calory is provided by glucose 300gm/day either orally or parenterally as 10-20% solution. Fluid & electrolyte balance should be maintained accoding to body need. 4. Circulating function- should be corrected & maintained by i.v fluid, colloid and blood transfusion. 5. Respiratory failure: Oxygen supplementation or assisted pressure ventilation. 6. Control of haemorrhage: Haemorrhages due to failure of coagulation factors production- Inj. vitamin-K may be helpful. Blood or fresh frozen plasma or platelete (if available) may also be given. GI haemorrhage can be prevented by- Inj. Ranitidine 50mg i.v over 2 hours then 8 hourly. 7. Infections : Prophylactic antibiotic should not be used. When infection is present (common in 90% cases)- Co-amoxiclav or cefotaxime may be given intravenously. 8. Early administration of acetylcysteine (initially 150mg/kg then 10mg/kg hourly) may improve the survival, (which is mostly indicated for paracetamol toxicity). 9. If renal failure: haemodialysis can be done. 10. Liver transplantation: The mortality rate of fulminant hepatic failure with severe encephalopathy is as high as 80%. Emergency liver transplantation may help with an 80% survival rate at one year. |
| Management | |
| Introduction | Acute (fulminant) hepatic failure may be defined as ‘hepatic failure with encephalopathy developed in a patient within 8 weeks after the onset of acute liver disease’. When encephalopathy occurs between 8 weeks to 6 months after the onset of acute liver disease then it is called ‘subacute or subfulminant hepatic failure’. Fulminant hepatic failure is a rare but often life-threatening syndrome;. majority of which are due to acute viral hepatitis; paracetamol overdose may also be a common cause. In fulminant hepatic failure due to hepatitis, extensive necrosis of large areas of the liver gives the typical pathologic picture of acute liver atrophy. |
| History | |
| Etiology | |
| Clinical Features | Clinical feature: Features for encephalopathy: 1. Reduced alertness, restlessness, mania to coma. 2. Inversion of sleep rhythm 3. Flapping Tiepatic’ tremor 4. Extensor planter response 5. Unequal or abnormally reacting pupil to light. Features for hepatic failure: 1. Fetor hepaticus 2. Toxaemia 3. Gastrointestinal symptoms, and haemorrhagic phenomena are common. 4. Jaundice may be absent or minimal, but laboratory tests show severe hepatocellular damage |
| Preventions | |
| Treatment | |
| Complications | Complications of acute hepatic failure2 1. Hepatic encephalopathy 2. Cerebral oedema with increased intracranial pressure 3. Respiratory failure 4. Hypotension 5. Hypothermia 6. Secondary infection 7. Haemorrhagk disorders 8. Pancreatitis 9. Renal failure 10. Metabolic disorders a. Hypoglycaemia b. Hypolkalaemia c. Hypocalcaemia d. Hpyomagnesaemia e. Acid-base disturbance |
| Prognosis | |
| Types | |
| Classification | Classifications of acute hepatic failure2 Acute hepatic failure can be classified in to three categories on the time interval of development of .jaundice and encephalopathy and presence of cerebral oedema or not. I. Hyperacute: Encephalopathy develops within 7 days of development of jaundice. Cerebral oedema usually present. Common causes are viral hepatitis and paracetamol. II. Acute: Encephalopathy develops within 8-28 days of development of jaundice. Cerebral oedema usually present. Common causes are cryptogenic or drugs. III. Subacute: Encephalopathy develops within 29 days to 12 weeks of development of jaundice. Cerebral oedema usually not present. Common causes are cryptogenic or drugs. Clinical grading of hepatic encephalopathy:2 Grade 1 - Poor concentration, slurred speech, slow mentation, disordered sleep rhythm. Grade 2 - Drowsy but easily reusable, occasional aggressive behaviour, lethargic. Grade 3 - Marked confusion, drowsy, sleepy but responds to pain and voice, gross disorientation. Grade 4 - Unresponsive to voice, may or may not respond to painful stimuli, unconscious. |
| Observation | |
| Pathology |
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