1. Health Occupations
Lymphatic System

2. Functions of the Lymphatic System
Works in conjunction with CV system
Filters out organisms that cause disease
Produces WBCs
Makes antibodies
Drains excess fluids & protein so tissues do not swell up

3. Lymphatic fluid Thin & watery Called interstitial fluid Composed of
Forms when plasma diffuses into tissue spaces
Composed of
Water
Digested nutrients
Salts
Hormones
Oxygen
CO2
Lymphocytes
Metabolic wastes

4. Vessels & Organs of the Lymphatic System
Found in almost all tissues that have blood vessels
Lymphatic capillaries
A. Tubes that reach into interstitial spaces
B. Small, open-ended like drain pipes
C. Lymph fluid contains waste products & foreign bodies from cells
D. Fluid moves from capillaries to lymph vessels

6. Vessels & Organs of the Lymphatic System
Lymphatic capillaries also have
LACTEALS – specialized capillaries
found in small intestine
1. Pick up digested fats
2. Lymph + Lipids = Chyle
3. Transports chyle to
bloodstream via thoracic duct

7. Vessels & Organs of the Lymphatic System
Lymphatic vessels
Similar to veins
Muscular contractions help to move lymph from tissues to lymphatic trunks
Valves prevent backflow of lymph so it moves in only one direction, towards heart
Fluid empties in lymphatic trunks which empty into veins & then become part of the blood plasma

8. Vessels & Organs of the Lymphatic System
Lymph nodes
Lie along lymph vessels
Small, round or oval masses
Size of pinhead to almond
Usually found in groups or clusters
Job is to filter lymph & remove impurities like carbon, CA, pathogens, dead blood cells
Also produce lymphocytes & antibodies
Purified lymph with lymphocytes & antibodies added leave node via ONE lymphatic vessel
Found in neck, armpit, chest, abdomen, elbows, groin, knees

9. Vessels & Organs of the Lymphatic System
Lymphatic ducts – all lymph vessels drain into these
Right lymphatic duct
Short tube receiving all purified lymph from right side of head, neck, right chest, & right arm
Drains into right subclavion vein
Thoracic duct
Drains purified lymph from rest of body
Empties into left subclavion vein
Cisterna chili – enlarged pouch like start of thoracic duct
Serves as storage area for purified lymph before it returns to blood stream
Picks up chyle (digested lipids) from lacteals

11. Vessels & Organs of the Lymphatic System
Tonsils
Masses of lymph tissue that are external
Filter interstitial fluid, not lymph
If too much bacteria is filtered, pathogen can overwhelm tonsils & they can become infected
3 pairs of tonsils
Palatine tonsils – on each side of soft palate
Pharyngeal tonsils – adenoids, in nasopharnyx
Lingual tonsils – on back of tongue

12. Vessels & Organs of the Lymphatic System
Spleen
A. Organ located beneath left side of diaphragm & behind upper stomach
B. Filters microorganisms & wastes
C. Makes lymphocytes & monocytes
D. Destroys old erythrocytes & stores RBCs to release into bloodstream if there is excessive bleeding
E. Destroys platelets

13. Vessels & Organs of the Lymphatic System
Thymus
Mass of lymphatic tissue located in front of aorta & behind sternum
Stores lymphocytes to defend body only in CHILDREN
Atrophies after puberty & is replaced by fat & connective tissue
During childhood, makes lymphocytes & antibodies
Function is taken over by lymph nodes in adults

14. Immunity Lymph system helps body remove foreign & harmful substances
1. Antigen – foreign matter that causes body to produce antibodies (poison, splinter, bacteria)
2. Antibody – substance made by body to produce immunity to antigen

15. 2 forms of immune response
Nonspecific – innate, provides general protection
Barrier of skin, mucous membranes, tears, leukocytes
1. Forms antibodies in response to antigens or foreign material
Inflammatory response - localized
Injured cells cause release of chemicals, causing vascular dilation & increased blood flow
Other molecules enter area, wall off injured tissue
Bacteria are destroyed by WBCs
Area is red, warm, painful, & often swollen with decreased function

16. 2 forms of immune response
Inflammatory response – systemic
Affects entire body
Same as localized, but with increased neutrophils, fever, & fluid loss in tissues
If not stopped, can lead to shock & death
Specific immunity
A. Inherited – develops before birth, is genetic (example – humans don’t contract simian AIDS)

17. 2 forms of immune response
B. Acquired
1. May be natural or artificial, depends on how it was attained
a. Natural acquired
unintentional exposure like
immunity from breast milk
b. Artificial acquired
obtained intentionally like immunization

18. Immune response may damage tissue
With allergen exposure, plasma & memory cells produced. The next exposure causes anaphylactic response
Cytoxic response when antibodies react with cells causing cellular destruction (RH incompatability)
Phagocytes released to remove antigen-antibody complexes & their actions cause by-products that can cause tissue damage
Delayed hypersensitivity – occurs more than 12 hours after exposure & results in tissue damage

19. Abnormal conditions
Lymphadenitis – inflammation or infection of lymph nodes
A. Occurs when large amounts of harmful substances enter lymph nodes
B. Symptoms – fever, swollen, painful nodes
C. If untreated, nodal abscess may form
D. Treatment – warm moist compresses, antibiotics, occasionally drain abscess

20. 2. Hodgkin’s lymphoma Chronic, malignant disease of lymph nodes
Most common form of lymphoma
Symptoms
Painful swelling of nodes
Fever
Night sweats
Weight loss
Fatigue
Pruritis (itching)
Treatment
Chemo & radiation

21. 3. Lymphangitis
Inflammation of lymph nodes, usually from infected extremity
Symptoms
Red streak extending up an arm or leg from source of infection
Fever
Chills
Pain or tenderness
Treatment
Antibiotics
Rest & elevation
Warm, moist compresses

22. 4. Lymphedema Caused by lymphatic obstruction
Commonly occurs after lymph node removal
Especially after mastectomy

23. 5. Splenomegaly Enlargement of spleen Causes Symptoms
Abnormal accumulation of RBCs
Mononucleosis
Cirrhosis of liver
Symptoms
Swelling & abdominal pain
Can lead to anemia, leucopenia, thrombocytopenia
If spleen ruptures, hemorrhage & shock, if untreated, death
May need to remove spleen

24. 6. Tonsillitis Inflammation or infection of tonsils
Usually pharyngeal or palatine tonsils
Symptoms
Throat pain
Dysphagia (difficult swallowing)
Fever
Exudate on tonsils
Swollen mandibular lymph glands
Treatment
Antibiotics
Warm saline irrigations
Analgesics
May remove with chronic infection or enlargement