Acute Liver Failure Flashcards
Pod Doc Episode
What are the features of liver failure?
Deranged INR
Encephalopathy
What time frame divides acute liver failure and chronic liver disease?
Less than 6 months= Acute
> 6 Months = Chronic
Purely acute liver failure occurs without a background of liver failure- acute on chronic is a sudden decompensation in a patient with a background of chronic liver disease
What defines hyper-acute liver failure?
Features within seven days
What defines acute liver failure?
Features within 7-28 days
What defines sub acute liver failure?
Features within 4-26 weeks
What are the durations that define acute liver failures actually referring to?
The duration of time from when jaundice first noticed to the development of encephalopathy
What is meant by acute on chronic liver failure?
This is the development of acute liver failure, triggered by physiological insult, on a background of chronic liver disease
Patients decompensate- jaundice, ascites, encephalopathy
What is the leading cause of acute liver failure?
Paracetamol overdose in the UK
Note- in the East the leading cause is hepatitis
What is meant by sero-negative acute liver failure?
Features of acute liver failure (deranged INR + encephalopathy) but no cause is known and there are no indications of autoimmune causes (of currently known antibodies)
Also called Non-A and Non-B
What would you expect on the LFTs indicating an acute liver failure?
Massively raised AST and ALT
What are some causes of acute liver failure?
Paracetamol
Hepatitis
Ischaemic hepatitis
Seronegative
Why is it important to check renal function in patients with acute liver failure?
They’re at risk of developing hepatorenal syndrome
The liver releases vasoactive substances which disrupt the perfusion to the kidneys and can cause renal injury- this can lead to death and mortality is high
What blood tests are important markers of liver function?
Albumin
INR
What is recommended for fluid resus in acute liver failure? Why?
Colloids are recommended. The liver is being degraded and there is massive release of inflammatory cytokines which causes a massive immune reaction and there is systemic vasodilation. Giving crystalloids can lead to cerebral oedema as they are in a very fluid permeable state.
Why is GCS important to check in acute liver failure?
They develop hepatic encephalopathy and cerebral oedema- especially as a complication of fluid resuscitation.
What are some features of hepatic encephalopathy?
Drowsiness Agitation Aggression Coma Asterixis
What is asterixis?
The inability to draw a 5 pointed star- it is a test for hepatic encephalopathy but is rarely done. Especially in acute liver failure, it has more use in chronic patients developing hepatic encephalopathy.
What can indicate the development of hepatic encephalopathy?
Declining GCS scores
Drowsiness, Agitation, Aggression
Comatose
Hepatic flap
What infection cover is needed for patients with acute liver failure?
Antibiotics and Antifungals as bacteremia can occur in upto 80%.
Note- this is still true if the patient is culture negative
Why are patients with acute liver failure at a massively increased risk of bacteremia?
Patients are at risk of bacterial and fungal infection and so antifungal and antibacterial cover is needed
This is because the liver is a detoxifying organ that is vital for immune function
Why are acute liver failures given PPIs?
They’re at risk of stress ulceration
What is given to reduce cerebral oedema?
Mannitol IV
Why do the patients with acute liver failure die?
Sepsis
Infection
Multi-organ failure due to hypoperfusion
Cerebral oedema and hepatic encephalopathy
What INR defines coagulopathy?
INR>1.5
What causes hepatic encephalopathy?
Build up of ammonia, this is eventually causes an osmotic pressure which can precipitate cerebral oedema
