The Lymphatic System

Lymphatic System -Consists of: Lymph, lymph vessels, lymph nodes and lymphatic tissue

-System works in conjunction with the circulatory system to remove waste and excess fluids from the tissues

-Lymph-a thin watery fluid composed of intercellular and interstitial fluid which forms when plasma diffuses into the tissue spaces.

◦ -Components are: water, digested nutrients, salts, hormones, oxygen carbon dioxide, lymphocytes, and metabolic wastes like urea.

-Lymphatic Vessels-small open-ended vessels that act as drain pipes are located throughout the body where blood vessels are found. AKA Lymphatic capillaries-Capillaries connect to larger vessels that then take fluid to lymph nodes. -Capillaries also contain valves that only allow fluid to travel in one direction.-Skeletal muscle contraction aides in movement of fluid through the vessels.

Lymphatic Capillaries

Lymphatic System -Lacteals are specialized lymphatic capillaries found in the small intestine.

-These pick up digested lipids and transport them back to the thoracic duct.

-Lymph mixed with lipids is called Chyle

Lymphatic System Lymph Nodes- AKA Lymph glands, are small round or oval shaped masses that are found all over the body.

Usually located in clusters, these masses vary in size from that of a pin-head to the size of an almond.

Vessels bring lymph to the nodes where it is filtered to remove impurities such as; carbon, cancer cells, pathogens and dead blood cells.

Node tissue also produces lymphocytes (a type of white blood cell that fights infection) and specific antibodies.

This purified lymph with antibodies and lymphocytes leaves the node through a single vessel; as the fluid drains from one vessel it continues to flow into larger and larger vessels eventually draining into one of two lymphatic ducts.

Lymphatic System

Lymphatic System Lymphatic Ducts

◦ -Right Lymphatic Duct-Short tube that receives all the purified lymph from the right side of the head and neck, the right chest and the right arm. It dumps into the right subclavian vein, returning the lymph to the blood.

-The Thoracic Duct-largest duct in the body collects the lymph from everywhere else. The duct drains into the left subclavian vein to return fluid to the body.◦ -At its beginning is a large pouch like structure where purified lymph is stored called the cisterna chyli.◦ -The Cisterna Chyli also receives chyle from the intestinal lacteals

Lymphatic System Right Lymphatic Duct Thoracic Duct

Lymphatic System Lymph Tissue is also found in other parts of the body as well those include:

◦ The Tonsils: Filter interstitial fluid and are found in three pairs: Palatine Tonsils; located on either side of the soft palate, Pharyngeal Tonsils; located in the nasopharynx aka adenoids, Lingual tonsils; located at the back of the tongue

◦ -The Spleen; Organ located beneath the left side of the diaphragm and in the back of the upper part of the stomach.

◦ -The Thymus-Located in the center of the upper chest of children, it atrophies after puberty and is replaced by fat and connective tissue.

Lymphatic System Tonsils

Main function is to trap pathogens.

Whether its through the nose or mouth

Lymphatic System Spleen

-Produces leukocytes and antibodies

-Destroys old erythrocytes (old red blood cells)

-Stores erythrocytes for release in cases of excessive bleeding

-Destroys thrombocytes (platelets)

-Filters metabolites and waste from body tissue

Lymphatic System The Thymus

Early in life it produces antibodies and lymphocytes

It is replaced by the lymph nodes when the system matures

Helps to fight infection

Problems in the Lymphatic System

Adenitis◦ Inflammation or infection of the lymph nodes◦ Occurs when large quantities of dangerous

substances enter the nodes such as cancer cells or pathogens and infect the tissue

◦ Symptoms include: fever, and swollen painful nodes

◦ If untreated can lead to abscess of the node◦ Treatment includes antibiotics and warm

compress◦ Abscess may require incise or draining of the

node

Problems in the Lymphatic System

Hodgkin’s Disease◦ Chronic Malignant Disease of the lymph nodes◦ Most common form of lymphoma (tumor of the

lymph tissue)◦ Symptoms include: pain and swelling of nodes,

fever, night sweats, weight loss, fatigue, and pruritus (itching)

◦ Treatment is chemotherapy and radiation therapy

Problems of the Lymphatic System

Lymphangitis◦ Inflammation of the lymphatic vessels◦ Results from infection within the extremity◦ Symptoms include: red streak running up the

arm from source of infection, fever, chills, tenderness, pain

◦ Treatment includes antibiotics, rest elevation of affected part, warm moist compress

Problems of the Lymphatic System

Splenomegaly◦ Enlargement of the spleen◦ Results from: abnormal accumulation of RBC,

mononucleosis, and cirrhosis of the liver◦ Symptoms include: swelling and abdominal pain,

anemia due to destruction of RBCs, leukopenia or low WBC count and Thrombocytopenia or low platelet count

◦ If spleen ruptures then hemorrhage and shock can lead to death

◦ If underlying cause cannot be flushed out then splenectomy is performed. (Removal of Spleen)

Problems of the Lymphatic System

Tonsillitis◦ Inflammation or infection of the tonsils◦ Usually involves the pharyngeal and palatine

tonsils◦ Symptoms include: throat pain, dysphagia, fever,

white or yellowish spots on the tonsils, swollen lymph nodes near the mandible

◦ Treatment: Antibiotics, warm throat irrigations, rest, and analgesics for pain

◦ Chronic infections or enlargement that causes obstruction are indications for tonsillectomy