HEPATIC ENCEPHALOPATHY Flashcards
Overview (4)
- Neuropsychiatric syndrome which occurs with advanced hepatocellular disease
- Toxic substances normally detoxified by the liver bypass the liver by the collaterals and gain access to the brain
- Ammonia plays a major role and is produced from breakdown of dietary protein
- May occur acutely (fulminant hepatic failure) or acute-on-chronic in patients with cirrhosis following precipitating factors, such as:
- High dietary protein
- Gastrointestinal hemorrhage ( —> a high protein load)
- Constipation
- Infection including spontaneous bacterial peritonitis
- Fluid and electrolyte disturbance (spontaneous or diuretic-induced)
- Sedative drugs e.g. opiates, diazepam
- Portosystemic shunt operations (except splenorenal shunt) and TIPS
- Any surgical procedure
- Progressive liver damage
- Development of hepatocellular carcinoma
Symptoms and signs (6)
1- Increasingly drowsiness, hypertonia, and hyperreflexia
2- Chronically, the patient may be irritable; confused; with slow, slurred speech and a reversal of the sleep pattern (sleeping during the day and restless at night)
3- Fetor hepaticus (a sweet smell to the breath)
4- Asterexis (flapping tremor of the outstretched hand)
5- Constructional apraxia (inability to draw a five-pointed star)
6- A prolonged trail-making test (ability to join numbers and letters in a certain time)
Clinical Grading
0 —> No alteration in consciousness, intellectual function, personality, behavior
1 —> Daytime somnolence, short attention span, mild asterexis
2 —> Lethargic, drowsiness, disoriented usually in time, inappropriate behavior, obvious asterexis
3 —> Asleep but arousable, confusion, incomprehensible speech
4 —> Coma
Investigations (3)
1- Diagnosis is clinical (must rule out other metabolic or toxic encephalopathies or intracranial mass lesions)
2- Arterial blood ammonia: to follow patients
3- EEG (showing delta waves) and visual evoked potentials may be used in difficult diagnostic cases
