1-70 Anatomy Flashcards
Lympth functions
– Drain excess fluids from body tissues (2-4 liters/day)
– Re-circulate proteins from blood capillaries
– Absorb emulsified fat via lacteals in intestinal villi
– Body defense mechanism. 2 kinds of lymphocytes:
B-cells differentiate into plasma cells for
antibody production (humoral immunity)
and memory cells
T-cells (killer cells) for cell-mediated immunity
(3rd cell type: natural killer (NK) cells)
Lymph vessels junctions
Lymphatic vessels in general have little smooth muscle. Junctions between capillary endothelial cells (below right) do not have junctional complexes. Note the absence of a basal lamina.
Most lymph enters the blood circulation at the junction of the internal jugular and subclavian veins via:
- Jugular trunks
- Subclavian trunks
- Bronchomediastinal trunks
The thoracic duct from the lower body only goes to the veins on the left.
Schematic of left-right lymph drainage
Lymph drainage into the veins of the neck is bi-laterally symmetrical above umbilicus because of the paired trunks.
All lymph below umbilicus goes to the left veins via the thoracic duct.
Exception: deep thoracic body wall drains into thoracic duct; it all ends up on the left
Stratification of lympth flow
Lympth flow in leg
Superficial lymph flows up to the superficial inguinal Lymph nodes.
Deep lymph follows the large vessels (popliteal, femoral, etc.) to the deep inguinal nodes under the deep or investing fascia at or within the femoral canal.
Lymph Flow from Lateral Foot and Ankle, and Posterior Calf Drain Deep into Popliteal Nodes
Superficial inguinal lympth nodes
Nodes are in the superficial fascia around the greater saphenous vein.
Efferents will pierce the deep fascia to go to deep inguinal nodes around the femoral sheath.
Femoral sheath
Superficial and deep lymph converge on the femoral sheath enveloping the:
- Femoral artery
- Femoral vein
- Lymphatics
Medial to lateral:
- Lymphatics through the femoral canal
- Femoral vein
- Femoral artery
- (The femoral nerve is outside the sheath.)
The lymphatics pass through the medial femoral canal – the site of femoral hernia.
Stratification of lymph flow: anal/rectum
Aortic lymphatics recieve lymph from…
The entire lower body!
GI lymph flow into…
Aortic lymph vessels
Mesenteries are rich in lymph vessels and nodes because of their proximity to the external environment (intestinal lumen).
below the diaphragm, All lower lymph converges on the…
- cysterna chyli and then goes to thoracic duct**
- The thoracic duct drains the thoracic body wall, but not the heart & lungs.
- It joins the veins on the left side of the neck.
** Exception: upper liver drains directly through diaphragm.
Arm lymphatics
- Superficial AND deep lymph in the upper extremity flow to the axillary lymph nodes.
- The subclavian trunk drains lymph from the axillary nodes into the veins of the neck on each side.
Lymph Drainage from the Heart and Lungs:
Bronchomediastinal Trunks
Note:
– Thoracic duct (1), jugular (2) & subclavian (3) trunks
– Other smaller lymph vessels entering the veins (internal thoracic, etc.)
– Lymph passing to opposite sides
Lympth draininage of breast
- Upper lateral breast –> axillary nodes
- To opposite breast
EXCEPTIONS to the plan:
- Parasternal nodes deep to body wall
- Superficial inguinal nodes.