3.5. Liver + Biliary Tree Disease - Portosystemic Encephalopathy Flashcards
What is Portosystemic Encephalopathy?
This is a neuropsychiatric condition
What is Encephalopathy?
Irritation of the Brain
What is Portosystemic Encephalopathy secondary to?
Liver Cirrhosis / Hepatic Failure
What are the main predisposing factors to Portosystemic Encephalopathy?
- Gastrointestinal Haemorrhage
- Constipation
- Infection
- Drugs
- Fluid/Electrolyte Disturbances
- Surgical Procedures
- Toxic Substances
In which Group of people is Constipation a common source of Portosystemic Encephalopathy?
The Elderly
What infections can cause Portosystemic Encephalopathy?
- Urinary Tract Infections - These are the most common
- Chest Infection (URTI/LRTI)
- Spontaneous Bacterial Peritonitis - this must be rules out as a cause
What type of drugs can lead to Portosystemic Encephalopathy?
Central Nervous System Depressants
What can cause Fluid / Electrolyte Disturbances?
- Diuretic Therapy
2. Paracentesis
What Surgical Procedure, used in the Liver, can commonly lead to Portosystemic Encephalopathy?
Transjugular Intrahepatic Portocaval Shunt (TIPS)
What Toxic substances, in high levels, may be a causative factor?
- Ammonia
- Free Fatty Acids
- Thiols
- False Neurotransmitters (e.g. Octopamine)
- The activation of the Gamma-Aminobutyric Acid System (An inhibitory neurotransmitter)
What is the Pathology of Portosystemic Encephalopathy?
- The exact mechanism is unknown, but it is multifactorial
- Due to the Aetiology, Toxins are not deal with properly by the Liver
- These allow the Toxins to remain in the Blood which will irritate the Brain
What are the Clinical Signs of Portosystemic Encephalopathy?
- Asterixis (Hepatic Flap)
- Fetor Hepaticus
- Decreased Blood Pressure
- Decreased Blood Glucose
- Decrease Blood Urea
- Decreased Mental Function
- Confusion to Coma
What is Asterixis?
A flapping tremor caused by Hepatic Failure
What is Fetor Hepaticus?
Sweet Smelling Breath
Why does Fetor Hepaticus occur in Portosystemic Encephalopathy?
Portosystemic Shunting allows Thiols into the Lungs