Hepatic Encephalopathy 1. Definition • It is the occurrence of confusion, altered level of consciousness, and coma as a result of liver failure. • In the advanced stages it is called hepatic coma or coma hepaticum. • It may ultimately lead to death. • It is caused by accumulation in the bloodstream of toxic substances that are normally removed by the liver. • The diagnosis of hepatic encephalopathy requires the presence of impaired liver function and the exclusion of an alternative explanation for the symptoms.
2. Causes (all the details in the table in PPT should be memorized) Type
Causes
Excessive
Consumption of large amount of protein, GI bleeding, renal failure,
nitrogen load
constipation
Electrolyte
Hyponatraemia, hypokalaemia these are both common in taking
(or) metabolic diuretics, used for treatment of ascites, hypoxia, dehydration disturbance Drug
& Sedatives such as benzodiazepines, narcotics, antipsychotics, alchohol
medications
intoxification
Infections
Pneumonia, urinary tract infection, spontaneous bacterial peritonitis
Others
Surgery
Unknown
No clear cause
3.Pathogenesis (ammonia Intoxication, false Neurotransmitters, amino Acid imbalance, the gamma-amino butyric acid hypothesis )
4.Symptoms (mental, physical) Mental Mild
Physical
Mild confusion
Change in sleep patterns
Short attention span
Difficulty writing or doing other small
Forgetfulness
hand movements
Mood swings
Breath that smells musty or sweet
Personality changes
Slurred speech
Inappropriate behavior Difficulty doing basic math Severe Marked confusion
Extreme sleepiness
Severe anxiety or fearfulness
Slowed or sluggish movement
Disorientation regarding time and place
Shaking of hands or arms (called
Inability to perform mental tasks such as
“flapping”) Jumbled, slurred speech that can’t be
doing basic math
understood
5. Asterixis (defination, pathogenesis)
Asterixis (also called the flapping tremor, or liver flap) is a tremor of the hand when the wrist is extended
In more severe conditions of HE, Shaking of hands or arms is seen physically (c/a flapping)
6.Severe form of HE (feature: "slience") : people can become unresponsive, unconscious and enter a coma 7.Classification (4 grades should be remembered) Level
Mental Status
Flapping tremor
I
Slightly
Weak positive
II
Somnipathy
and
Positive
inappropriate III
Drowsy and psychopath
Positive
IV
Deep coma
Positive
8.Diagnosis (type A, B, C)(methods) Type
A HE + Acute liver failure, associated with cerebral oedema
(Acute) Type
B Portal systemic shunting without associated intrinsic liver disease
(Bypass) Type
C Patient with cirrhosis. Subdivided into episodic, Persistent,
(Cirrhosis) Minimal encephalopathy Type A,C Confirmed liver disease 9. To make the diagnosis of encephalopathy:
Type B Portosystemic shunt
Exclude underlying causes (such as listed above in "causes") Distinguish hepatic encephalopathy from other conditions (such as brain disease) The diagnosis of hepatic encephalopathy can only be made in the presence of confirmed liver disease (types A and C) or a portosystemic shunt (type B), as its symptoms are similar to those encountered in other encephalopathies. •
liver function tests
•
ultrasound
•
liver biopsy
•
CT scan (to exclude haemorrhage)
•
electroencephalograph (EEG, to exclude seizure activity)
Rarer mimics of encephalopathy are meningitis, encephalitis, Wernicke's encephalopathy and Wilson's disease; these may be suspected on clinical grounds and confirmed with investigations
10. Treatment principles Eliminating or correcting precipitating factors Reducing plasma ammonia and other toxin Correcting plasma amino acid imbalance and supplying normal neurotransmitters Improving hepatocyte functions Liver transplantation
11. Lactulose, antibiotics Since toxins originally arise in GI system, therapies are aimed at gut to eliminate or reduce the production of toxins. There are two types of medications : Lactulose: Works by drawing water from your body into your colon, which softens stools and causes you to have more bowel movements. This helps to lessen the absorption of toxins in your intestines by flushing toxins out of your system. Reduces the amount of ammonia in your blood by drawing the ammonia into the colon where it is removed from the body.
Antibiotics: Work by stopping the growth of certain bacteria that create toxins from your digested food. By reducing these bacteria, antibiotics reduce the amount of toxins produced in your body.