Lymphatic System

which body system does lymphatic system work with

circulatory system

functions of lymphatic system

• maintain tissue fluid balance

• fight infection

• assist removal of extracellular debris and waste

• transport fat from digestive system

what exists in extracellular space

plasma, interstitial fluid

what does microcirculation unit consist of

capillary bed, moving plasma and interstitial fluid

describe how body fluid moves from blood to lymphatic system

fluid from plasma leaves capillary bed from arterial end into interstitial fluid, some fluid return to venous end, leftover fluid from extracellular space and proteins are collected by lymph nodes

ways fluid crosses capillary wall

diffusion, osmosis, ultrafiltration

describe diffusion

movement of molecules from high concentrated areas to low concentrated areas

describe osmosis

movement of fluid across a semi-permeable membrane towards high molecularly concentrated areas

describe starling’s principle of fluid dynamics

fluid exchange across capillary wall is a balance between hydrostatic pressure and osmotic colloidal pressure

osmotic colloid pressure is also known as

oncotic pressure

what molecule does fluid move towards in osmotic colloidal pressure

albumin

which pressures push fluid out of capillary wall

plasma hydrostatic pressure, tissue colloidal osmotic pressure

which pressures pull fluid into capillary wall

plasma colloidal osmotic pressure, tissue hydrostatic pressure

which pressures do most of the work in microcirculation unit

plasma hydrostatic pressure, plasma colloidal osmotic pressure

describe ultrafiltration

when plasma hydrostatic pressure is greater than plasma colloidal osmotic pressure, so fluid ultimately leaves capillary wall

origin of plasma hydrostatic pressure

blood pressure from heart pumping

origin of plasma colloidal osmotic pressure

albumin in capillary

origin of tissue hydrostatic pressure

fluid in extracellular space

origin of tissue colloidal osmotic pressure

small amount of proteins that leak into tissue

describe reabsorption

fluid that returns to the capillary

components of lymph

water, protein, fat, urea, salt, insulin, bacteria, lymphocytes

list primary lymph organs

red bone marrow, thymus

list secondary lymph organs

lymph nodes, spleen, tonsils, appendix, Peyer’s patches

purpose of primary lymph organs

lymphocyte formation and maturation, B cell maturation, T cell maturation

purpose of secondary lymph organs

• monitor lymph, tissue fluid, blood

• activate lymphocytes

what drives lymphatic system

pressure, vessel pumping, muscular contractions

describe lymphatic capillary

blind-ended tubes with single layer of overlapping endothelial cell layer that work as one-way flaps

describe anchoring filaments

extensions from lymphatic capillary that attach to surrounding tissue, opens up flaps of lymphatic capillary to bring in interstitial fluid

describe pre-collector

smooth muscle that contracts lymph from capillary to collector

describe collector

smooth muscle that is made up of lymphangion, contracts lymph to lymph nodes

describe lymph node

filled with lymphocytes and macrophages, filters lymph by checking for pathogens

describe territories

areas of skin that drain to one regional lymph node group

describe watersheds

boundaries between territories

list of watersheds in human body

medial-sagittal/vertical, transverse/horizontal

describe anastomoses in lymphatic system

connecting neighboring territories across watersheds

list of lymphatic anastomoses

interaxillary, axillo-inguinal, inter-inguinal

list of lymph node groups

cervical, axillary, inguinal

describe lymphatic trunk

lymph drains from lymph node to here

list of lymphatic trunks

jugular, subclavian, bronchomediastinal, intestinal, lumbar

describe cisterna chyli

sac at base of thoracic duct, collect lymph and fat from intestinal and lumbar trunks

describe lymphatic ducts

lymph nodes drain into ducts, right lymphatic duct or thoracic duct

describe right lymphatic duct

lymph drains from right arm and right side of head and chest

describe thoracic duct

lymph drains from areas other than right arm and right side of head and chest

where does lymph return fluid to circulatory system

right or left subclavian vein depending on duct

define lymphadenopathy

swollen lymph nodes

define lymphadenitis

infected lymph node

describe transport capacity

ten times amount of normal lymph load, maximum capacity of lymph the lymphatic system can transport

root cause of lymphedema

lymph load is greater than transport capacity due to dynamic failure and/or mechanical failure of lymphatic system

causes of greater lymph load

higher capillary pressure, lower plasma protein, leakier capillaries, more protein in tissue

describe dynamic failure of lymphatic system

excess fluid

examples of dynamic lymphatic system failure

ankle sprain, knee replacement

describe mechanical failure of lymphatic system

damaged lymphatics

examples of mechanical lymphatic system failure

lymph node removal from breast cancer removal

examples of both dynamic and mechanical lymphatic system failure

chronic venous insufficiency

leading US cause of lymphedema

mechanical failure of lymphatic system

describe primary lymphedema

absence or decrease of lymph vessels at birth, abnormality in lymphatic vessels

describe secondary lymphedema

blockage or interruption of lymphatic system

define lymphorrhea

lymph weeping through skin

describe stage 0 lymphedema

reversible, heaviness or aching

describe stage I lymphedema

reversible, swelling decreases with elevation of limb, pitting edema

describe stage II lymphedema

irreversible, no change with elevation of limb, fibrosis begins, pitting occurs that fades

define fibrosis

toughening of skin

describe stage II lymphedema

irreversible, extensive swelling, non-pitting edema, fibrosis, darkening of skin, wart-like growth, skin folds

1+ pitting edema

slight pitting, rebounds immediately

2+ pitting edema

somewhat deep pitting, rebounds in a few seconds

3+ pitting edema

noticeably deep pitting, rebounds in 10-30 seconds

4+ pitting edema

very deep pitting, rebound in more than 30 seconds

exception for compression and manual lymph drainage to treat lymphedema

active deep vein thrombosis, uncontrolled heart failure, untreated infection

describe circumferential measurement of lymphedema assessment

comparing volume of bilateral limbs to check for swelling by measuring circumferences, not the most accurate but easy to use

describe volumetric water displacement measurement of lymphedema assessment

water displaced from separate bilateral limbs compared, most reliable measurement but hard to challenging to localize swelling, should not be used with open wounds or skin infection

lymphedema volume criteria

10% or greater, 200 mL or greater

lymphedema circumference criteria

1-2 cm or greater increase, 2 cm or greater difference from unaffected limb, increase at 2 or more consecutive sites

positive stemmer’s sign

skin cannot be lifted

negative stemmer’s sign

skin lifts normally

which stemmer’s sign directly indicates lymphedema

positive stemmer’s sign

describe complete decongestive therapy

manual lymph drainage, compression therapy, exercise, skin care

describe manual lymph drainage

gentle, rhythmic massage to move lymph fluid towards lymph nodes

describe compression in CDT

using short stretch bandages to apply more distal pressure up towards lymphatic trunks, pressure from compression contributes to ultrafiltration

differentiate short stretch and long stretch bandages

short produces low pressure at rest and high pressure during movement, long produces high pressure at rest and low pressure during movement

how does exercise help reduce swelling from lymphedema

muscle contractions apply pressure and help move lymph

describe lymphangitis

infection of lymphatics due to skin infection, lymphedema, lymph node removal, diabetes

signs of lymphangitis

red streaks up limb, rash

treatments for lymphangitis

penicillin, antibiotics

differentiate cellulits and erysipelas

cellulitis affects deep skin and fat, erysipelas affects superficial skin and superficial lymphatics

treatments for cellulitis and erysipelas

anitbiotics

describe lipedema

symmetrical enlargement of legs, deposits of subcutaneous adipose tissue, sensitive to touch

key indicators of lipedema

negative stemmer’s sign, no swelling at feet

treatments for lipedema

CDT, nutrition guidance, pain management