Pa2010 lymphatics

Glacier National Park

Grimmell Glacier

FUNCTIONS OF THE LYMPHATIC SYSTEM

I. Drainage of tissue fluid and macromolecules back into the circulation.

II. Absorption and transport of fat

III. Filtration of lymph

IV. Dissemination of cancer cells

FACTORS INVOLVED IN LYMPH FLOW

1. Smooth muscle in walls of lymph vessels

2. Compression of vessels due to contraction of surrounding muscles

3. Negative pressure in thorax generated by respiratory movements

4. Gravity

5. Pulsations of arteries

Blood capillary

Arteriole

Lymph capillary

Venule

Tissue cell

Interstitial fluid

Interstitial fluid

Endothelium of lymphcapillary

Anchoring filament

Opening

Lymphatic capillaries

• begin as blind-ended tubes

• converge to form larger lymphatic vessels

Lymph CapillaryTissue Space

(Interstitium)

Blood Capillary

Arterial End Venous End

Water

Proteins

Oxygen

Dust Particles

Bacteria

80-90 % of fluid returns to blood stream

1.5-3 L / 24 hrs

Lymph Capillary

Tissue Space

(Interstitium)

Blood Capillary

Arterial End Venous End

1.5-3 L / 24 hrs

"An adult who weighs 160 pounds has about 5 quarts (4.7 liters) of blood."

Lymph CapillaryTissue Space

(Interstitium)

Blood Capillary

Arterial End Venous End

Fluid componentBlood Capillary = Plasma

Tissue Space = Interstitial Fluid

Lymph Capillary = Lymph

COMPONENTS OF THE LYMPHATIC SYSTEM

I. Vessels

A. Capillaries

1. Not distributed evenly throughout the body

a. Dense meshwork beneath the surfaces of the body

b. Sparse in muscle, bone and fascia

c. Absent in avascular tissues

B. Small lymphatic vessels

Contain numerous valves

C. Large lymphatic vessels (Trunks or Ducts)

Contain numerous valves

II. Lymph Nodes

A. Organized accumulation of lymphoid tissue

B. Scattered along lymphatic vessels

C. Vary in size

D. Basic concept of flow of lymph through lymph nodes

E. Function as filters of lymph

F. As a general rule, lymph flows through at least one lymph node before it is returned to the circulation

III. Aggregations of lymphoid tissue

A. Peyer’s patches ( in small intestines)

B. Tonsils

C. Bone marrow

IV. Lymphoid organs

A. Spleen

B. Thymus

V. Circulating T and B lymphocytes

Inguinal nodes

Iliac nodes

Pink Area: Lymph drainage via the right lymphatic duct

Gray Area: Lymph drainage via the thoracic duct

Intestinal Trunk

Left Lumbar Trunk

Thoracic Duct

Right Lumbar Trunk

Left Jugular Trunk

Left Mediastinal Trunk

Thoracic Duct

Left Subclavian Trunk

Right Mediastinal Trunk

Right Lymphatic Duct

Right Jugular Trunk

Right Subclavian Trunk

• Lymphadenectomy - Removal of a lymph node.

• Lymphadenopathy - Enlarged, sometimes tender, lymph nodes.

• Lymphadenitis - Enlarged, tender, and inflamed lymph nodes resulting from an infection

• Lymphangioma - A benign tumor of the lymphatic vessels.

• Lymphangitis - Inflammation of the lymphatic vessels.

• Lymphedema - accumulation of lymph fluid producing subcutaneous tissue swelling.

• Lymphoma - Any tumor composed of lymphatic tissue

• Lymphostasis - A lymph flow stoppage.

• Splenomegaly - Enlarged spleen

• Elephantiasis - Long-standing edema of one or both lower extremities, and sometimes of the arms or other body parts, that is due to lymphatic obstruction.

Medical Terminology Associated with the Lymphatic System

Glacier National Park