Acute liver failure

Question 1

What is acute liver failure?

Answer 1

Rapid onset of liver dysfunction without prior disease. Generally lasting less than 6 months.

Question 2

What are the main functions of the liver?

Answer 2

Protein metabolism, Lipid metabolism
Carbohydrate metabolism
Imunological defence
Bilirubin metabolism
Hormone and drug metabolism
Bile acid secretion
Storage
Protein synthesis

Question 3

What are the true liver function tests?

Answer 3

Bilirubin, albumin and prothrombin. MOST important as they are prognostic markers

Question 4

What are the liver ‘damage’ liver function tests?

Answer 4

GGT, AKP, ALT/AST and bilirubin

Question 5

What percentage of patients with cirrhosis have normal LFTs?

Answer 5

17%

Question 6

What are the features of acute liver failure?

Answer 6

1) Encephalopathy,
2) Coagulopathy (prolonged prothrmbin time)
3) Jaundice

Question 7

What are the common symptoms of acute liver failure?

Answer 7

None!
Jaundice
Lethargy
nausea
Itchy
Pain (capsule stretching)
Abnormal LFTs
Anorexia

Question 8

What are the causes of acute liver failure?

Answer 8

1) Viral (Hep A-E, CMV, EBV and toxoplasmins)
2) Drugs (many)
3) Shock liver
4) Cholangitis
5) Alcohol
6) Malignancy
7) Chronic liver disease
8) Paracetamol
RARE: Budd Chiarri, AFLP, Cholestasis of pregnancy

Question 9

What is Shock liver?

Answer 9

Inadequate perfusion of the liver. (Hypotention- check the vascular patency of the hepatic artery)

Question 10

What is Budd Chiarri?

Answer 10

Occlusion of hepatic veins which drain the liver.

Question 11

What is AFLP?

Answer 11

Acute fatty liver disease of pregnancy

Question 12

When you ask a patient about paracetamol what else should you ask?

Answer 12

Preparations
OTC drugs which contain paracetamol.
Even 4g/day for 2 weeks can change liver function.

Question 13

What are the directly toxic causes of liver failure?

Answer 13

Drugs, alcohol, virus and hypoperfusion (shock liver)

Question 14

What are the immunologic causes of liver failure?

Answer 14

Primary Billary Cirrhosis

Autoimmune hepatitis

Question 15

What are the nutritional causes of liver failure?

Answer 15

NASH, Malnutrition, refeeding syndrome.

Question 16

What are the genetic causes of liver failure?

Answer 16

Wilsons disease and haemachromatosis (insidious onset and can present with HHC)

Question 17

What are the investigations to consider in acute liver failure?

Answer 17

Bilirubin, Prothrombin, Albumin.
LFTs
Ultrasound including vascular
Virology
Immunological serology
Rarely a liver biopsy.

Question 18

When is a liver biopsy indicated?

Answer 18

Struggling to get a clear diagnosis or looking at the patients prognosis

Question 19

Acute liver failure history?

Answer 19

Duration
Drugs (OTC, illicit, herbal and food supplements)
Alcohol, unusual hobbies, travel, sexual history.

Question 20

What is the treatment for acute liver failure?

Answer 20

Supportive. Rest 3-6 months.
Fluids and NO alcohol.
Increase calories (high protein, low fat)
Observe for FHF

Question 21

What is puritus and what is the cause?

Answer 21

Severe itching of the skin caused by increase in bilirubin- often post hepatic picture.

Question 22

What is the treatment for puritus?

Answer 22

Sodium bicarbonate bath
Cholestyramine (prevents bile salt reabsorption)
Uresodeoxycholic acid (reduces cholesterol absorption)

Question 23

What are the metabolic considerations in acute liver failure? WHat should people be eating?

Answer 23

Patients are in a hypermetabolic state and require increased nutritional requirements but are often not hungry.
35-40 calories/Kg/day
1.2-1.5g protein/kg/day.
Monitor K, PO4 and Mg for signs of refeeding syndrome.
Monitor blood glucose for hyper/hypoglycemia
Consider NG feeding in some patients

Question 24

What are the features of a hepatic drug reaction?

Answer 24

Occurs about 6 weeks post exposure- the first effect may not have been noticed.
Often the liver is predisposed. Eg NASH.
Caused by any drug, many mechanisms and variation in LFT abnormalities.
Effects CP450 => free radiacl production and lipid peroxidation.

Question 25

How does paracetamol toxicity come about?

Answer 25

Paracetamol is metabolised to NAPQI (toxic) as it comsumes most of the GLUTATHIONE. Glutathione is usually recycled in the liver but when bound to NAPQI it is not.

Question 26

How is Paracetamol toxicity treated?

Answer 26

NAC is given which is the precursor to glutathione. You need to give it faster then it is being used.

Question 27

What are the common drugs which cause liver reactions?

Answer 27

Co-amoxiclav, Flucloxacillin, NSAIDs
Fat burners/protein powders
Paracetamol containing drugs
(statins can change LFts but don’t normally cause liver damage.)

Question 28

What is Fulminant Hepatic failure?

Answer 28

Rapid development of encephalopathy in a previously normal liver

Question 29

What are the causes of FHF?

Answer 29

Paracetamol
Viral
Drugs
RARE: AFLP, mushrooms, malignancy, Wilsons disease, Budd Chiari

Question 30

What are the clinical features of fulminant hepatic failure?

Answer 30

Encephalopathy => cerebral oedema (may require decompression)
Spontaneous hypoglycemia
Coagulopathy
Circulatory failure
Renal failure => dialysis
Infection

Question 31

What is the treatment for fulminant hepatic failure?

Answer 31

Supportive: Fluids and Ionotropes to increase BP.
Renal replacement,
Manage raised Intra cranial pressure
Transplant

Question 32

What are the survival outcomes of fulminant hepatic failure?

Answer 32

75%, 65% if require transplant.

Question 33

What should you do if you suspect fulminant hepatic failure?

Answer 33

Refer quickly to a 24 hour transplant centre (Edinburgh)
Monitor closely (bloods every 6 hours)
If they need transplant get it within 24 hours (Die within 48-72 hours)
Consider intubating to reduce cerebral oedema and effects

Question 34

What are the guidelines for transplant called?

Answer 34

Kings Collage Criteria for Acetaminophen (paracetamol toxicity)
There are also guidelines for non paracetamol fulminant liver failure