Lesson 2B (Part 1) Flashcards
Lymphatic system
Network of tissues and organs that primarily consists of lymph vessels, lymph nodes and lymph
What are components of the lymphatic system? (4)
- Tonsils
- Adenoids
- Spleen
- Thymus
How many lymph nodes are part of the human body?
600-700
What do lymph nodes do?
Filter the lymph before it returns to the circulatory system
- lot more lymph going in than coming out
What are the functions of the lymphatic system? (4)
- Transport clean fluids back to the blood
- Drains excess fluids from the tissues
- Removes debris from the cells of the body
- Transports fats from the digestive system
What direction does lymph flow?
Only one direction
- upward toward the neck
How does lymph flow?
It goes into the venous blood stream through the subclavien veins
- which are located on either sides of the neck near the collarbones
What are the 2 drainage systems of the lymphatic system?
- Right
2. Left
What does the right drainage system handle? (2)
- The right arm
2. Chest
What does the left drainage system handle?
Clears all of the other areas of the body
- including both legs, the lower trunk, the upper left portion of the chest, and the left arm
Where do afferent lymphatic vessels enter the lymph node?
At the hilus
What happens inside a lymph node?
It gets scrutinized by macrophages and lymphocytes ready to mount an immune response
Where does lymph exit from a lymph node?
Efferent lymphatic vessel
How does lymph get cleaned?
By passing through several nodes
Why is it significant that there are more afferent then efferent lymphatic vessels?
Because there is a lot more going into the lymph node than coming out because its filtering
Infection
Infected material may enter lymph vessels from infected tissues and if the phagocytosis is not effective then infection may spread from node to node
Lymphagitis
Inflammation of lymph vessels
Lymphadenitis
Infection of lymph nodes
Lymphadenopathy
Enlargement of lymph nodes
Splenomegaly
Enlargement of the spleen
Lymphoedema
Swelling in tissues whose lymphatic drainage has been obstructed in some way
Where are the 2 cervical chains located?
- Anterior
- Posterior
- important to scan all the way down to the clavicle and up to the ear
What should a normal lymph node look like? (10)
- Small
- Oval
- Hilum present
- Moderate echogenicity
- Sharp margins, no structural changes
- Soft tissue edema
- Central vessel on Doppler
- Single vascular pedicle
- Regular vascular pattern
- Low impedence
When does enlargement of the cervical lymph nodes commonly occur?
With a viral infection
What is the reactive lymph nodes look like?
Same as the normal lymph nodes
What is the difference between normal and reactive lymph nodes?
Reactive nodes are are usually small, firm and non-tender and they may persist for weeks to months
What do abnormal lymph nodes look like? (11)
- Large
- Rounded
- Hilum absent
- Hypoechoic
- Irregular, angular, blurred margins
- Structural changes
- No edema
- Peripheral vessel on Doppler
- Multiple vascular pedicles
- Chaotic vascular pattern
- High impedance
Lymphatic obstruction
Lymph vessel is obstructed, and lymph accumulates distal to the obstruction
- lymphoedema
What is the result of lymphatic obstruction?
Swelling and the size of the area affected depend on the size of the vessel involved
What does lymphedema lead to?
Low-grade inflammation and fibrosis of the lymph vessel and further lymphoedema
What are the most common causes for lymphedema?
An accumulation of lymph fluid that occurs if the lymphatic system is damaged or not functioning properly
- tumours
- following surgical removal of lymph nodes
Lymphedema
Chronic swelling of the limbs
Where does lymphedema occur?
Typically the limbs but can also involve the face, neck and abdomen
