Hepatic disease Flashcards
(125 cards)
What can cause acute liver injury/ failure?
Prolonged ischaemia Drugs Toxins Neoplasia Metabolic disorders Infectious disease (e.g. Lepto) Immune-mediated disease
What toxins can cause acute liver injury/ failure?
Aflatoxins Amanita mushrooms Blue-green algae Cycad palms Xylitol
What drugs can cause acute liver injury/ failure?
Phenobarb Paracetemol Oral benzodiazepines (cats) Carprofen Lomustine Mititane Sulphonamides Zonisamide Itra/kenoconzaole Glipizide Methimazole/ carbimazole Rifampicin Tetracycline
Which infections can cause acute liver injury/ failure?
FIP Lepto Infectious Canine Hepatitis Salmonellosis Toxoplasmosis Platynosum fastosum
How can acute liver injury cause hepatic encephalopathy?
Combination of hyperamonaemia, excitatory neurotoxicity, oxidative stress, altered permeability of the blood-brain barrier, inflammation, neurosteroid-induced GABA receptor modulation within the CNS
What can precipitate hepatic encephalopathy?
Hypokalaemia (increases renal tubule ammoniogenesis)
Hyponatraemia (risk factor for cerebral oedema)
Metabolic acidosis (facilitates ammonia diffusion into the CNS)
Can you have normal ammonia levels and hepatic encephalopathy?
Yes
How can you manage seizures caused by hepatic encephalopathy?
Leviteracetam ideally, can also do propofol
There is some evidence that diazepam may play a role in the pathogenesis of HE so avoid if possible
What other treatment should be given for hepatic encephalopathy apart from controlling seizures?
Emergency - warm water cleansing enema (10mL/kg) to reduce the number of ureae-producing bacteria in the colon
Follow with a lactulose retention enema, then oral
Metronidazole (lowered dose of 7.5mg/kg) or ampicillin
Manitol if intracranial pressure is suspected due to cerebral oedema
Avoid excessive protein restriction as this may increase ammonia in the blood due to endogenous protein catabolism (monitor protein levels by measuring albumin). Ideal is a heptaic diet with cottage cheese added
Why/ when give antimicrobial prophylaxis in acute liver injury/ failure?
Secondary infection is a major cause of death
Only give when there is a vasopressor non responsive hypotension, progression or HE, positive culture of infection
Give a broad spec AB
Why give antacids with liver injury/ failure?
High risk of gastro-duodenal ulceration Omeprazole H2 agonist Also sucralfate Evidence that gastric pH is elevated with liver disease, so the effects of an H2 agonist are unclear
Why make vitamin K be low with acute liver injury/ failure? (empiric therapy recommended)
Poor oral intake
intra or extra hepatic cholestasis
AB use may affect the microbiome and reduce vit K2 producing bacteria
What is the prognosis for acute liver injury/ failure?
Low, one study said 14%
Why do animals with liver disease get ascites?
Normally due to portal hypertension
Only sometimes is it hypoalbuminaemia
How do you treat ascites in liver disease?
If low protein - high quality protein, e.g. soya or cottage cheese
Portal hypertension - (tx underlying thing also!) Spironolactone over frusemide, K+ sparing. Can take 2-3 days for effect. Only use frusemide to speed things up.
Do not drain unless it is life threatening (rare)
Why is GI ulceration common with liver disease
Portal hypertension leads to gut wall oedema, leads to ulceration
When should you not use metoclopramide with liver disease
When there is HE
When should maropitant be avoided with liver disease?
Significant liver dysfunction (metabolised by the liver)
What is the antacid of choice for liver disease?
Ranitidine
Which antacid is indicated for paracetemol toxicity?
Cimetidine - involved with P450
What is the antidote for paracetemol toxicity?
N-acetylcysteine - a glutathione precursor.
It binds the toxic metabolite and increases glucoronidaton.
SAM-e also useful to replenish glutathione, which inactivates the toxic metabolite
How do you treat potentiated sulphonamide toxicity?
N-acetylcysteine also useful, treat the signs.
How do you treat phenobarb toxicity?
Some dogs develop hepatocutaneous syndrome on long term therapy
Ideally withdraw and replace with a drug not metabolised by the liver (e.g. KBr)
SAM-e v useful as it is a precursor for antioxidant and detoxifying systems of the liver
What is the typical appearance of hepatocutaneous syndrome on ultrasound
Liver has a swiss cheese appearance