Lymphatic system Flashcards
What is lymph
thin fluid that resembles plasma
what is lymph from GI tract called?
chyle
How many litres of lymph is produced a day
3-4
Describe the structure of lymphatic vessels
not open ended have endothelial cells at end
valves between endothelial cells- allows flow to be unidirectional
What forces valves in lymph vessels to open?
oncotic pressure
Explain lymph flow dynamics
valves- unidirectional flow
oncotic pressure forces valves open
muscle contraction aids lymph movement
some larger lymph vessels have SM in walls
adjacent to cv vessels compress lymph vessel propelling lymph
where is the lymphatic system not found
brain
what is the functional unit of a lymph vessel called
lymphagion
what sort of valves are present in lymphatic trunks or ducts
fibrocartilaginous valves
what trunk/duct does chyle drain into
cisterna chyli
where does lymph from upper R quadrant flow
right subclavian vein and internal jugular vein
where does lymph from everywhere but the R quadrant flow to
left subclavian vein and internal jugular vein
what is the role of lymph nodes
filter lymph on way to vascular system
what are lymph nodes in neck called
cervical
what are lymph nodes in groin called
inguinal
what are lymph nodes in the armpit called
axillae
Describe lymph nodes
kidney shape
several afferent lymphatic vessels on convex surface
single efferent vessel on concave surface ( hilium)
also feeding artery and draining vein that enter and leave by hilium
contain follicles ( germinal centres) with immune cells
reticulin fibers
capsule is made from collagen I and III
what are enlarged lymph nodes called
lymphadenopathy
what is cancer in lymph nodes called
lymphoma
hodgkins and non hodgkins
Name 6 lymphatic organs
thymus spleen tonsils vermiform appendix payer patches
Where is the thymus? what is its role?
superior mediastinum
similar to lymph node but no hilium
T cell maturation
Where is the spleen? what is its function?
inferior diaphragm
posterior stomach
red and white pulp
filter blood
white pulp–> immune function–>apc/ activate b/ t cells/ remove macromolecular antigens from blood
red pulp –> haemopoeitic function –> remove old erythrocytes
Where are the tonsils? What are their function?
oropharynx / nasal pharynx
nodules inferior to surface crypts
prevent pathogen ingress through nasal/ orally/aurally
surface Microfold cells that are APC s
swelling results form t and b cell proliferation
Where is the vermiform appendix? what is it role?
inferior to and attached to caecum (ascending colon)
nodules inferior to crypts like tonsiles
Microfold cells on surface
what are payer’s patches
inferior to and attached to ileum
nodules inferior to crypts again
m fold cells on surface
prevent pathogen ingress through digestion
what are the main functions of the lymphatic system
fluid balance
transport fats and fat soluble vits (chyle)
defence against pathogens
storage and destruction of erythrocytes
how can sentinel lymph nodes be used to look for cancer spread?
first ones to swell methylblue fluoroglucose injected probe identify metabolically active tissue identify metastatic tissue
Name causes of primary lymphodema
congential (milroy's disease) - FLT4 gene mutation--> missing endothelial cells in vessel wall before 2 Praecox (Meige diease) - 2-36 yr unknown cause TARDA- over 35 unknown cause
Name causes of secondary lymphodema
neoplasia surgery radiotherapy autoimmune infection
main treatment for lymphodema?
lympha press
