Information Leaflet
Irish National Liver Transplant Unit
Encephalopathy
Encephalopathy is also known as hepatic encephalopathy, hepatic coma and portalsystemic encephalopathy.
What is encephalopathy?
It is the deterioration of brain function due to toxic substances building up in the
blood, which are normally removed by the liver.
The liver metabolises and detoxifies digestive products brought from the intestine by
the portal vein. In patients with liver disease these products escape in to the general
circulation either because the blood in the portal vein bypasses the liver cells or
because the cells themselves are damaged and don’t work properly.
The toxic substances are not precisely known but ammonia, a by product of protein
digestion probably plays an important role.
What are the symptoms of encephalopathy?
Personality changes such as inappropriate behaviour, altered mood and impaired
judgement are common early manifestations that may precede a change in
consciousness. Short term memory may be affected such as forgetting telephone
numbers, names or appointments and family members or medical staff would be the
first to recognise this symptom.
Initially, subtle sleep pattern changes or sluggish movement and speech may be
present. Drowsiness, confusion, stupor and frank coma indicate increasingly
advanced encephalopathy.
Patients demonstrate an inability to reproduce simple designs, for example, a star, this
is a characteristic early sign. A peculiar, characteristic flapping tremor, asterixis, is
elicited when the patient holds his arms outstretched with hands bent back at the wrist
and the fingers spread out.
What factors can cause encephalopathy and how are they treated?
Constipation can cause encephalopathy. If waste products/toxins are held in the
bowel for a prolonged period of time, reabsorption of toxins occurs which may
increase the incidence of encephalopathy. Main therapy is with oral Lactulose
which is normally given to prevent constipation in an initial dose of 20-30mls
three times a day and should be adjusted to maintain two or three soft bowel
motions daily.
Infection may also cause a similar rise in toxins and precipitate an encephalopathic
event. Infection should be treated promptly with an appropriate antibiotic. This may
require admission to hospital for intravenous antibiotics. In some patients with
chronic encephalopathy it may be necessary for them to take an antibiotic on a regular
basis.
Haemorrhage can also cause an increase in toxins as the blood is being digested.
Vomiting blood or passing black tarry stools is an emergency situation and should be
treated in your nearest Accident and Emergency Department.
What are the different grades of encephalopathy and what are the specific
symptoms?
Grade 1:
Grade 2:
Grade 3:
Grade 4:
Confused. Altered mood or behaviour. Loss of memory for simple
facts. Slowness of thought process.
Increasing drowsiness. Inappropriate behaviour.
Stuporous but speaking and may/may not obey simple commands.
Inarticulate speech.
Marked confusion.
Restless.
Agitated.
Aggressive.
Coma.
Once the precipitating factor has been identified and treated the encephalopathic
episode generally resolves. If the encephalopathy becomes severe and results in coma
the patient will require ventilation in an Intensive Care Unit. This means that they
will be placed on a breathing machine to assist their breathing and to protect their
airway. Again, once the cause has been identified and treated this situation can
generally be reversed.
Sedation should be avoided in patients experiencing episodes of encephalopathy.
Patients experiencing encephalopathy should avoid driving, operating machinery,
working with dangerous instruments or working at heights/on ladders as these
activities may pose a danger to themselves or others.
Patients experiencing encephalopathy are generally unaware of their confused state
and therefore are not always co-operative with family members or carers.
Encephalopathy may be an unpleasant experience for both the family and the patient.