1. ST120: Concorde Career College
Lymphatic System
ST120: Concorde Career College

2. Lymphatic System Objectives: Define the term lymph.
Describe the functions of the lymphatic system.
List and identify the structures of the lymphatic system and describe the function of each.
Identify the origin of lymph.

3. Lymphatic System Objectives: Trace the flow of lymph through the body.
Describe the immune system and describe the immune response.
Describe the mechanism by which the immune system helps to maintain homeostasis.

4. Lymphatic System Objectives:
Describe common diseases, disorders, and conditions of the lymphatic system including signs and symptoms, diagnosis, and available treatment options.
Demonstrate knowledge of medical terminology related to the lymphatic system verbally and in the written form.

5. Functions of the Lymphatic System
Removal of impurities
Lymphocyte processing

6. Lymphatic System
The lymphatic system parallels (same direction)the circulatory system
Lymph vessels return tissue fluid to the blood & protect the body against foreign material
The lymphatic system includes:
Lymph fluid
Lymph vessels
Lymph nodes
Spleen
Thymus
And tonsils

7. Lymph Fluid
Lymph is the tissue fluid that enters and travels through the lymphatic vessels
Plasma flows out of blood capillaries into tissue spaces (interstitial fluid) – AKA Tissue fluid
Plasma diffuses out of the capillaries faster than it is reabsorbed, the remaining interstitial fluid is returned to the blood through the lymphatic system

8. Lymphatic Capillaries
Lymphatic Capillaries - Carry lymph and resemble blood capillaries
Lacteals - Specialized lymphatic capillaries that carry chyle

9. Lymph Vessels
Vessels of the lymphatic system start with the smallest blind (dead-ended) lymph capillaries
The walls of the lymphatic capillaries are a thin walled, single layer of loosely fit squamous epithelial cells making them highly permeable
Lymphatic capillaries join larger lymphatic arterioles that then join lymphatic arteries
Lymphatic vessels like the veins of the circulatory system have valves

10. Lymph Flow

11. Relationship of Lymphatic Vessels to Circulatory System
Lymphatic System
Relationship of Lymphatic Vessels to Circulatory System

12. Thoracic Duct
Lymph returns to the blood flow through the thoracic duct and the left subclavian vein
Lymph from the lower body returns through the thoracic duct
Cisterna chyli – dilation at the beginning of the thoracic duct (pouch-like structure)
Lymph from a portion of the upper body also empties into the thoracic duct superior to the cisterna chyli
Lymph from the upper left quadrant empties into the subclavian vein
Two terminal vessels include: Right Lymphatic duct & thoracic duct

13. Lymphahtic Drainage

14. Lacteal Found in the villi of the small intestine
Responsible for absorbing fat-soluble nutrients (fatty acids and vit. A,D,E & K)
Fats are absorbed by the lacteals as chylomicron
Chylomicron: combination of fatty acids and glycerol to form triglycerides

15. Lacteal

16. Lymph nodes and nodules
Lymph Node: small ball shaped organs of the lymphatic system
Lymph Nodules: groups of lymph cells located beneath the epithelial layer of mucus membranes (ex. Respiratory tract and digestive tract)
Peyer’s patches: lymphatic nodules of the ileum
Filters pathogens and foreign material before returning to blood
Monitor the level of body fluid
Hematopoietic function – produce lymphocytes, macrophages, and monocytes
Located throughout the body
Cervical
Axillary
Inguinal

17. Regional Lymph Nodes

18. Lymph node Hilus Afferent vessels x4 pg.261 A&P Efferent vessels x1
Capsule
Germinal centers
Sinuses
Trabecula

19. Tonsils
Palatine Tonsils (throat) – located at each side of the oropharynx
Pharyngeal (Adenoids) – located on the posterior wall of the nasopharynx
Lingual Tonsils – located at the base of the tongue

20. Tonsils

21. Lymphedema Abnormal accumulation of fluid in interstitial spaces
Causes:
Obstruction of a lymphatic vessel (tumors, inflammation)
Increased capillary BP
Abnormal uptake of fluid by the lymphatic capillaries due to trauma or surgical wound (often seen after mastectomy)

22. Lymphedema

23. Lymphedema

24. Terms Lymphadenitis: inflammation of lymph node/vessels
Metastasis: is the spread of a disease from one organ or part to another non-adjacent organ or part, causing a new cancer site
Lymphadenopathy: Any disease that usually involves the lymph glands

25. Sentinel Lymph Node Biopsy
Method developed to determine if breast cancer has spread to lymph ducts or nodes in the axilla
Prevents the patient from having to undergo a lymph node dissection
Sentinel Node: first node the breast drains to
Nuclear Medicine
A radioactive dye is injected into the area where the tumor is located as well as around the areola
Hours later photos will reveal the pathway used to exit the breast, this will reveal the sentinel node OR
Surgeon injects a blue dye into the breast that assists in visual of the nodes
Small incision is made in the axilla
A special probe picks up signals form the radioactive dye and gets “excited” when over an affected node
All blue and radioactive nodes are removed

28. Spleen Highly vascular and friable (easily crumbled/delicate)
Located behind the stomach
Contains lymphoid nodules (white pulp)
Filters blood (red pulp) cleans out foreign materials/microorganisms
Stores blood (approximately 200 ml) aids in maintenance of BP during severe hemorrhage
Hematopoietic function: lymphocytes, monocytes, leukocytes, fixed plasma cells
In a fetus the spleen produces erethrocytes

29. Spleen
Hilus
Splenic artery
Splenic vein

30. Spleen cont.
#1 organ injured in MVA’s (motor vehicle accidents) despite being protected by the lower ribs
Splenectomy: surgical removal of the Spleen

31. Reticuloendothelial System
Lymphatic System
Reticuloendothelial System
Responsible for destruction of obsolete RBCs, bacteria, cancer cells, and other potentially harmful foreign substances.
Utilizes monocytes distributed throughout the body such as Kupffer’s cells located in the liver

32. Thymus Located in the mediastinum
Composed of two lateral lobes bound by a connective tissue capsule
Proper function dependent on thymosin
Produces T-cells important in cell mediated immunity

33. Thymus

34. Lymphatic System Lymphatic and Immune Systems Thymus Bone marrow
Spleen
Tonsils
Lymph nodes
Lymph capillaries
Lymph vessels
Lymphocytes
Lymph

35. Lymphatic System Immunologic Defenses
Provide the body with general defenses against disease.
Nonspecific Defenses
Specific Defenses

36. Lymphatic System Nonspecific Defenses Chemical and Mechanical Barriers
Phagocytosis
Natural Killer Cells
Inflammation
Fever
Interferon

37. Occurrence of Infection
Lymphatic System
Occurrence of Infection
Not every exposure to a pathogen results in infection.
Portal of Entry
Virulence
Toxins
Dose
Predisposition

38. Barriers Against Infection
Lymphatic System
Barriers Against Infection
Chemical
Body secretions
Mechanical
Skin
Mucous membranes
Cilia

39. First Line of Defense
Our first line of defense against microbes include:
Skin
Mucous membranes
Secretions

40. Skin Unbroken skin prevents microbes from entering the body (keratin)
Broken skin such as Burns, Cuts, Scratches open the doors for an invasion of microbes such as Staphylococcus aureus
Sweat glands and Sebaceous gland secrete acids that kill or inhibit the growth of bacteria on the skin

41. Mucous Membranes
Line tracts open to the exterior of the body (respiratory, digestive, urinary)
Goblet cells secrete mucous to line the membranes and “catch” microbes
Cilia catch and pass debris up to the pharynx to be expelled
Glands in the stomach produce highly acidic gastric juice that kills most bacteria
Helicobacter Pylori is an exception… can cause stomach and duodenal ulcers

42. Second Line of Defense
If pathogens penetrate the 1st line of defense they will encounter the body’s 2nd line of defense Circulatory and chemical defenses
Circulatory Defenses:
Phagocytes
Complement proteins
Iron
Fever
Inflammatory response
Interferons

43. Phagocytes Leukocytes responsible for phagocytosis
Phagocytosis: the process of surrounding and ingesting another microbe
Granulocytes
Neutrophils – motile and effective phagocytes
Eosinophils – attach to parasites and secrete peroxide ions which kill them. Play a larger phagocytic role during allergic response
Basophils
Agranulocytes
Monocytes – enter body tissues and mature into stationary macrophages or travel through blood to infection site (wandering macrophages)
Kupffer cells (liver), microglia (brain)
Lymphocytes – are not phagocytes but are important in the immune response

44. Phagocytosis
Chemotaxis – chemicals attract phagocytes to injured tissues or bacteria
Adherence – antibody molecules secrete a serum protein that can coat a bacterial cell and promote attachment (opsonization)
Ingestion – phagocyte surrounds the microbe
Pseudopods: “false feet” that extent to cover a microbe
The resulting sac is called a Phagosome
Digestion – phagosome is moved into the cytoplasm (phagolysosome) and enzymes (from the lysosomes) destroy the bacteria
Degranulation – digestion process

45. Complement proteins
Group of serum proteins found in blood plasma
Circulate inactive until needed in the antibody- antigen reaction
Activated Proteins: increase inflammatory response, assist in lysis of antigen, attracts phagocytes
Complement cascade: sequence of proteins “bore” holes into bacteria causing an accumulation of fluid that eventually ruptures the cell

46. Iron Virulence of bacteria increases when free iron is present
Leukocytes: produce interleukin-1 (IL-1), stimulates the liver to store iron depriving bacteria of necessary free iron

47. Inflammatory response
Inflammation is a beneficial and necessary response to injury
The four signs of inflammation include:
Pain
Heat
Redness
Swelling
Three stages of inflammation include:
Vasodilatation
Phagocyte migration
Tissue repair

48. Inflammatory Response
Vasodilation: Increased blood flow to area and increased permeability of blood vessels
Histamine, kinins, and prostaglandins: chemicals released by damaged tissues responsible for vasodilatation

49. Fever
An abnormally elevated body temperature (controlled by hypothalamus)
Systemic response frequently caused by viral or bacterial invasion
Symptoms include heat, shivering and increased metabolism rate
Vasodilatation and sweating signify the temperature falling “ fever breaking”

50. Interferons- produced by T-cells
Released to protect other cells by interferring with the ability of the virus to reproduce as it moves from cell to cell
Proteins produced by leukocytes, T-lymphocytes, and fibroblasts in response to infection “interfere with viral replication”
Proteins enter surrounding cells and inhibit the synthesis of proteins needed by invading viruses for multiplication
They interfere with viral replication
Pg. 269 A&P

51. Third line of Defense
Immune response: lymphocytes secrete antibodies that attach to microbes and inhibit or destroy them - - Called humoral antibodies
Formation of antibodies is stimulated by the presence of specific pathogens
Effective circulating antibodies gives us our immunity

52. Acquired Immunity Active acquired immunity:
Immunity that develops after a person has had a disease
Natural – individual has an infection and produces antibodies
Artificial – vaccinations
Attenuation: process of weakening a pathogen
Passive acquired immunity
Natural – antibodies pass through the placenta or in colostrum
Artificial – antiserum (immune individual > susceptible individual)
Pasteur – rabies vaccine
Sabin – polio vaccine

53. Lymphatic System Specific Defenses Immunity
Final defense against disease
Inborn (Passive)
Acquired
Natural (Active or Passive)
Artificial (Active)

54. Lymphatic System
Inborn Immunity
Species
Racial
Individual

55. Lymphatic System Acquired Immunity Develops throughout the lifespan
May occur naturally
May be induced

56. Natural Acquired Immunity
Lymphatic System
Natural Acquired Immunity
Active
Contraction of the disease
Antibodies protect from recurrence
May be long term or life long
Passive
Mother to fetus via placenta
Mother to infant via breast milk
May last six months or slightly longer

57. Artificial Acquired Immunity
Lymphatic System
Artificial Acquired Immunity
Immunization
Vaccines
Live
Weakened (attenuated)
Dead
Toxoid
Recombinant DNA
May be long term or life long

58. Cell-mediated Immunity
Humoral Immunity
Pg. 272 A&P
Cell-mediated Immunity

59. Antigens
Any substance that the body regards as foreign and stimulates the production of antibodies aka is immunogenic

60. Antibodies – A disease fighting protein created by the immune system in response to the presence of that specific antigen
Immunoglobulins produced by B-lymphocytes
Bind to receptor site of specific antigen
B-lymphocytes mature into:
Plasma cells – produce antibodies in response to an antigen (secretes them into blood)
Memory cells – produces antibodies quickly when the body is exposed to the same antigen again
Agammaglobulinemia: inability to produce antibodies (have no gammaglobulin)

61. T-cells: B-cells: Involved in cell-mediated immune response
Lymphoid stem cells that migrate to the thymus
Cytotoxic T cell:
Helper T cells:
Memory T cell:
Natural killer cell:
B-cells:
Function in Humoral immunity pg. 272 A&P

62. Organ Transplants
Tissue Rejection: cells of the recipient do not recognize the tissue of the donor as self and attack/destroy the transplanted tissue
To minimize chance of rejection recipients and donors tissue should be antigenically similar. Close family members are ideal donors
Immunosuppressive drugs: suppresses recipients formation of antibodies/suppress the immune system

63. Terms Isograft: genetically identical twin
Allograft: close family member
Xenograft: different species, Pig

64. Anaphylactic Reaction
Anaphylaxis: severe allergic reaction that can be life- threatening
Signs/Symptoms:
Itching, swelling, difficulty breathing, hives, urticaria
Severe difficulty breathing, laryngeal edema, bronchospasm
Treatment:
Epinephrine – bronchodilation, decrease laryngeal spasm, ^BP
Steroid – inhibit reaction
Levoped (vasopressor) - ^BP
Ringer’s Lactate – Fluids Box13-4

65. Latex Allergy
Many items used in the OR contain latex, daily exposure can cause a latex-sensitivity
Latex allergic patients should be scheduled as the first case of the day in an OR so there is not latex dust in the room form previous surgeries
Examples of latex in the OR
Tape, elastic bandages, electrode pads, gloves, tourniquets, endotracheal tubes,……….
Box 13-3

66. AIDS Acquired immunodeficiency syndrome (AIDS)
Human immunodeficiency virus (HIV) has the most obvious effect in certain types of T-cells – virus that causes AIDS
Characteristics:
Vulnerability to opportunistic infections
Major decrease in T-lymphocytes
Kaposi’s Sarcoma
Transmission:
Sexual contact
“dirty” hypodermic needles
mother > fetus
Blood transfusion

67. Hemolytic Transfusion Reaction
Occurs after a patient receives a transfusion of mismatched blood
Agglutination: clustering and destruction of RBC’s
Box 13-5

68. Autoimmunity
Autoimmune disorder: the bodies immune system regards normal body tissues as foreign. Can not distinguish self from non-self
Rheumatoid arthritis
Ulcerative colitis MS
Box 13-6