C11: Lymphatics Flashcards
What is the lymphatic system
Drainage system that returns extra cellular fluid into the blood stream
What are the 3 types of extra cellular fluid
Plasma
Interstitial
Lymph
Describe plasma. Where is it found
- colourless fluid found in blood
- seeps through capillary walls into tissue…
Describe interstitial fluid. Where is it found
-plasma that has seeped through the capillary walls into body tissue
Describe lymph. Where is it found
-fluid that was once in the body tissue but has now entered the lymphatic ducts
How is the lymphatic system different from circulatory system
- no pump
- flow is only in 1 direction
- contains lymph nodes
The lymphatic system courses along which other body system
Circulatory
The lymphatic sys consists of which structures
- capillaries
- vessels
- ducts
- nodes
Describe lymphatic capillaries… where are they found
- Blind ended structures found in interstitial spaces… there walls are 1 endothelial later thick
- capillaries join together to form larger vessels
Do lymph vessels have valves?
Yes
Describe the flow of lymph from the superficial vessels to the bloodstream
- superficial vessels at the subcutaneous level drain into the deep lymphatic vessels…
- the lymph in the deep vessels pass through the lymph nodes and travel towards the chest
- once at the chest the lymph re-enters the bloodstream
Lymph nodes are part of which larger body system
RE system
Where are lymph nodes located
How large are they normally
In clusters around the lymph vessels throughout the body
- measures 1 mm to 1-2 cm
Do lymph nodes have a capsule?
Yes
Made out of connective tissue
Describe the anatomy of a lymph node
- contains afferent vessels and efferent vessels
- has a capsule
- contains a sinus and germinal centres w/in the sinus
Describe the afferent lymph node vessels
-drain lymph into the node and carry it through the sinuses which are lined with phagocytic cells
What’s the function of the phagocytic cells found in the sinus of the lymph node
Filter out and destroy bacterial and cancer cells
What’s the function of the germinal cells found in the node
-produce lymphocytes which it empties into the lymph before it leaves the node
Do the afferent vessels have multiple entry points into the node?
What about the efferent vessels
Afferent: multiple entry sites
Efferent: exit only at the hilum and carry lymph out of the node
Are lymph nodes often the site of primary disease?
No
When is secondary disease sometimes seen in lymph node
W/ systemic infection and many neoplasms
Where are the 2 major lymph bearing areas in the retroperitoneum
- iliac and hypogastric areas/pelvis
- para-aortic/upper retroperitoneum
List 3 other areas that contain lymphatic tissue
- tonsils
- thymus (produces antibodies b4 puberty and produces lymphocytes)
- spleen
Does the lymphatic system have both deep and superficial channels of drainage
Yes
List the groups of nodes found at key locations
- axillary
- cervical
- inguinal
- intestinal
What name refers to the intestinal lymph nodes
Peyer’s patch
The R lymphatic duct drains which area(s) of the body
RUQ
The L lymphatic duct drains which area(s) of the body
Another name for the L lymphatic duct
3/4 of the body
-thoracic duct
Where does the lymph drain back into the blood stream
@ the junction of the subclavian vein and IJV
Does lymph have a higher of lower albumin ratio that blood plasma?
What type of blood cells does it contain? Which does it not?
Does it contain digestive enzymes?
- higher ratio
- has small amount of WBCs but no RBCs
- yes to digestive enzymes
Describe lymph flow…. what does it depend on
- slow when resting
- depends on contraction of muscles…. valves in larger vessels to prevent back flow
List the functions of the lymphatic system
- phagocytosis
- immunity
- tissue drainage
- excretion
How does the lymphatic system carry out excretion
Through absorption and circulation of end products of fat digestion
Are lymph notes typically seen in the abdo
What’s the AP diameter of abdo lymph nodes and what is there echoexture
No
AP: <1 cm
Homogenous (w/ low level echos)
What are some pitfalls when scanning lymph nodes
- enlarged para-AO nodes can mimic an aneurysm
- bowel gas
- enlarged nodes can make it hard to assess vessels
- fluid filled areas can hide enlarged lymph nodes
What’s it called when enlarged lymph nodes in the para-AO area push the AO anteriorly
Floating AO
when assessing at the pelvic level, we should be assessing along which muscles?
Psoas and iliacus
What is the function of albumin
Helps maintain osmotic press and fluid balance
Enlarged nodes Around the renal hilum can lead to……?
Hydronephrosis
