Lymphatics Flashcards
What are the three anatomic components of the lymphatic system?
lymph fluid, lymphatic vessels, and organized lymphatic tissues/ organs
what is the physiologic function of the lymphatic system?
it plays a major role in numerous homeostatic mechanisms of the body; maintain fluid balance, tissue cleansing, defense, and nutrition
when does lymphatic development begin?
during the 5th week of gestation
what happens when fluid overload occurs?
the lymphatic system helps prevent tissue damage by clearing the excess
what does the lymph node act as?
a purifying filter
how does the lymphatic system act as a defense mechanism?
lymph fluid brings toxins into contact with the organized lymph tissues, which contain high concentrations of immune cells
how does the lymphatic system aid in nutrition?
via fat absorption via chylomicrons
how do chylomicrons travel?
via lacteals into larger lymph vessels, which drain into the thoracic duct, which then drains into the venous system
What is lymph fluid?
substances that leak out of the arterial capillaries into the interstitium–> gets taken up by the lymphatic capillaries
what are the 4 tissues that do not have lymphatic vessels?
epidermis (including hair and nails), endomysium of muscle, cartilage, and bone marrow
what is the pathway of lymph?
terminal lymphatics–> collecting vessels–>afferent lymph vessels–>lymph nodes–> efferent lymph vessels–>lymphatic trunks–> thoracic duct or right lymphatic duct–>venous system
where does lymph formation begin?
in the interstitial space of tissues with the initial lymphatics/terminal lymphatics/ lymph capillaries
what makes up the collecting vessels?
chains of muscular units called lymphangions
what do lymphangions look like?
two-leaflet bicuspid valves
what is the role of the lymphangions?
they contract regularly throughout the lymphatic system move lymph in peristaltic waves
what is the innervation of the collecting vessels?
autonomic inenrvation
what is the most highly organized lymphoid tissue?
lymph nodes
what are the two types of lymph nodes?
superficial and deep
what is the pathway of lymph flow through a lymph node?
afferent lymphatics-subcapsular space-outer cortex-deep cortex-medullary sinus-efferent lymphatics
what region of the lymph node is rich in B cells?
outer cortex
what region is dominated by T cells?
deep cortex
where are the germinal centers found in the lymph node?
in the outer cortex
what do the lumbar lymphatic trunks drain lymph from?
lower limbs and pelvic organs
what do the intestinal lymphatic trunks drain lymph from?
the abdominal viscera
what do the bronchomediastinal lymphatic trunks drain lymph from?
portions of the thorax
what do the subclavian lymphatic trunks drain lymph from?
upper limbs
what do the jugular lymphatic trunks drain lymph from?
portions of the neck and head
what do the lymphatic vessels (efferent lymphatics) drain into?
lymphatic trunks
where is the cisterna chyli located?
at the level of L1-L2
what do the lymphatic trunks of the lower body drain into?
the cisterna chyli
what does the cisterna chyli give rise to?
the thoracic duct
what does the right lymphatic duct drain?
right head/neck, RUE, right thorax, heart, lungs (EXCEPT the LUL)
what is virchow’s node?
an enlarged node at the left supra-clavicular point
what is an enlarged virchow’s node indicative of?
intra-thoracic/ abdominal cancer
what are enlarged epitrochlear nodes (medial epicondyle) indicative of?
secondary syphilis
where is the spleen located?
beneath ribs 9-11 on the left
what does it mean when it is said that an organ is pressure-sensitive?
movement of the diaphragm drives the organ’s fluid movement
where is half of the body’s lymph formed?
in the liver
where is the thymus located?
anterior mediastinum
what replaces the thymus after puberty involutes?
fatty tisse
what is the function of the thymus?
maturation site for T cells; there is little to no function in adults
what are the 3 types of tonsils and where are they located?
all located in the posterior oropharynx; palatine, lingual, and pharyngeal
what is the visceral lymphoid tissue?
the GALT and the pulmonary lymphoid tissue
what two cell types make up the GALT?
peyer’s patches and lacteals
what is normal interstitial fluid pressure?
negative -6.3 mmHg
what happens when the interstitial fluid pressure rises above 0?
the lymph capillaries collapse and flow ceases
what could cause the interstitial fluid to rise above 0?
increased hydrostatic pressure, decreased plasma colloid osmotic pressure, increased capillary permeability
with each breath, what does contraction of the thoracic diaphragm cause?
it increases the negative intrathoracic pressure , which pulls the fluid centrally
when might the pelvic diaphragm contractions be dysfunctional?
dysmenorrhea, endometriosis, post labor and delivery, BPH
what is the effect of increased sympathetic tone on lymph valves?
it causes tighter valves, so therefore there is decreased lymph flow into the venous system
what is the effect of increased sympathetic tone on lymphatic smooth muscle?
it causes decreased peristalsis, which leads to lymphatic congestion
what are the main effects of edema?
compression of local structures, decreased tissue waste removal, decreased pathogen clearance and immunity
what are two absolute contraindications of lymphatic OMT?
anuria and necrotizing fasciitis
what are the fascial patterns of Zinc?
they describe the fascial restriction patterns that cause restriction of lymphatic flow
which zinc pattern is indicative for treatment?
uncompensated patterns
