Liver - arteries, veins, nerve, lymph & Percutaneous Liver Biopsy Flashcards
what type of blood supply does the liver have?
unique dual blood supply
what is the function of the hepatic artery proper?
supplies the liver with arterial blood
where is the hepatic artery proper derived from?
coeliac trunk
what does the hepatic portal vein supply the liver with?
supplies the liver with deoxygenated blood, carrying nutrients absorbed from the small intestine
what does hepatic portal vein carry?
carrying nutrients absorbed from the small intestine
what is the function of the hepatic portal vein in terms of the liver parenchyma?
This is the dominant blood supply to the liver parenchyma and allows the liver to perform its gut-related functions, such as detoxification
how is venous drainage of the liver achieved?
achieved through three hepatic veins
where do the 3 hepatic veins drain into?
inferior vena cava
what is the parenchyma of the liver innervated by?
The parenchyma of the liver is innervated by the hepatic plexus
what does the haptic plexus contain?
contains sympathetic (from the coeliac plexus) and parasympathetic (vagus nerve) nerve fibres
where do the sympathetic and parasympathetic fibres enter the liver at?
These fibres enter the liver at the porta hepatis
what course of travel do the sympathetic and parasympathetic fibres follow?
follow the course of branches of the hepatic artery and portal vein
what is Glisson’s capsule?
the fibrous covering of the liver
what is Glisson’s capsule innervated by?
innervated by branches of the lower intercostal nerves
what does distension of the Glisson’s capsule result in?
results in a sharp, well localised pain
where do the lymphatic vessels of the liver drain into?
hepatic lymph nodes
where do the hepatic lymph nodes lie?
These lie along the hepatic vessels and ducts in the lesser omentum
where do the hepatic lymph nodes empty into?
the coelic lymph nodes
what is a percutaneous liver biopsy?
A procedure used to obtain a sample of liver tissue
how do you carry out a percutaneous liver biopsy?
A needle is inserted through the skin to access the liver
when is a percutaneous liver biopsy required? give some examples of clinical scenarios
Abnormal LFTs of unknown cause.
Hepatitis C
Other liver conditions (such as Hereditary Haemochromatosis and Autoimmune Hepatitis)
Following liver transplantation
why is percutaneous liver biopsy used in hepatitis C?
Assessment for severity of liver fibrosis and disease progression
how is the liver located in the during a percutaneous liver biopsy?
During the procedure, the liver is located via ultrasound.
what is injected and where during a percutaneous liver biopsy?
Local anaesthetic is injected on the mid-axillary line, where on percussion there is dullness
what do you ask the patient to do during a percutaneous liver biopsy?
The patient is asked to deeply expire (avoiding damage to the lungs), and the needle biopsy is taken during held expiration
what do you do when a patient has an abnormal clotting?
If a patient has abnormal clotting (a contraindication for the procedure), a transvenous liver biopsy can be attempted.
what does a transvernous liver biopsy involve?
This involves cannulating the internal jugular vein, and passing the biopsy needle through to the hepatic veins, allowing for a biopsy sample to be taken.
