Lymphatics Flashcards
3 Components of Lymphatic System
- lymph fluid
- lymphatic vessels
- organized lymph tissue
Embryology
- Mesoderm
- Endoderm
- Mesoderm: lymphatic vessels, nodes, spleen
- Endoderm: thymus and part of tonsils
Fluid Balance
30 L fluid capillary–> interstital space
-90% to capillaries; 10% lymphatic system
Nutrition
- fat absorbed via chylomicrons
- travel via lacteals–> larger lymph vessels–> thoracic duct–> venous system
- returns proteins to vasculature
What tissues do not have lymphatic vessels
- epidermis
- endomysium of muscle
- cartilage
- Bone marrow
Lymphatic Vessels Route
Terminal lymphatics->collecting vessels->afferent lymph vessels->lymph node->efferent lymph vessels->lymphatic trunks->thoracic duct or R lymphatic duct->venous system
Terminal Lymphatics
- lymph formation starts interstitial space with initial lymphatics
- lined by leaky endothelium and enchored to ECM
- go into collecting vessels
Collecting Vessels
- have two-leaflet bicuspid valves to prevent retrograde flow
- contains smooth muscle
- autonomic innervation
- afferent prior to lymph node and efferents drain the node
Lymph Nodes
- superficial and deep
- filtration of lymph fluid
- maturation of lymphocytes
Path of Lymph Flow through a Node
- Afferent brings lymph to node
- subscapsular space: reticular fiber, dendritic cells initial immune response
- Outer Cortex: B cells
- Deep Cortex: T Cells
- Medullary Sinus: B cells and plasma cells
- Efferent lymph exits through Hilum
Lymphatic Trunk
Lumbar- drains lymph from lower limb and pelvic organs Intestinal- drains abdomen Bronchomediastinal- drains thorax Subclavian- drains upper limbs Jugular- drains upper head and neck
Cisterna Chyli
- located at L1-2
- drains lower body
- gives rise to thoracic duct
Thoracic Duct
- pierces Sibsons fascia twice and empties into L subclavian and L IJV
- Drains L head/neck, L UE, L thorax/abdomen, LL
Right Lymphatic Duct
- origin from R jugular and subclavian trunk
- terminates at R subclavian R/IJV junction
- Drains R head/neck, R UE, R thorax, heart, lungs
Spleen
- location: beneath ribs 9-11 on left
- characteristics: largest mass of lymphoid tissue, pressure sensitive
- Functions: destroys damaged RBC, clears bacteria, synthesizes immunoglobulin
Liver
- Location: RUQ
- Characteristic: pressure sensitive, relies on diaphragm
- Function: half lymph formed here, clears bacteria, gate keeper
Thymus
- Location: anterior mediastinum
- Characteristic: disappears at puberty
- Function: matures T cells
Tonsils
- Location: 3 types
- Characteristics: enlarged in childhood
- Function: provide cells to influence and build immunity early in life, nonessential to adults
Appendix
- Location: large intestine
- Characteristics: has lymphoid pulp
- Function: part of GALT
GALT
- Gastrointestinal Assoc. Lymphoid Tissue
- contains Peyers patches in ileum and lacteals in small bowel
- filters toxins
Mech of Flow
- Thoracic Diaphragm
- Pelvic Diaphragm
- Thoracic: contraction increases neg pressure and pulls fluid and exerts force on cisterna chyli
- Pelvic: helps move fluid from LE and pelvis to thoracic duct
SNS effects on
- lymph valves
- smooth muscle
- lymph valves: increased tone-> tighter valves-> decreased lymph flow to venous system
- Smooth muscle: increased tone-> decreased peristalsis-> lymphatic congestion
Edema
- increased edema-> continued increase in pressure-> lymphatic vessel collapse-> more edema
- compression of local structures: vascular-> delivery of O2, nutrients, neuronal-> decreased sensation, pain
- decreased tissue waste removal
- decreased immunity
- fibrosis
Absolute Contraindications for Lymphatic OMT
- Anuria
- Necrotizing fasciitis
Seq of Treatment
- open inlet, myofascial restrictors
- maximize diaphragmatic functions: abdominal and pelvic diaphragms
- increase pressure differentials or transmit motions: pumps
- mobilize targeted tissue fluids