LYMPHATIC SYSTEM

Question 1

What is the lymphatic system responsible for carrying back to blood?

Answer 1

Capillary ultrafiltrate fluid volume & escaped plasma proteins.

Question 2

What type of diuresis is the lymphatic system based on?

Answer 2

Osmotic diuresis.

Question 3

What are the four functions of the lymphatic system?

Answer 3

• Absorb macromolecules (proteins & FAs)
• Maintain fluid balance in tissue
• Fight infection
• Remove cell debris & waste products from extracellular spaces.

Question 4

What happens if normal lymphatic transport mechanisms are disrupted?

Answer 4

Lymphedema (latent, acute, or chronic).

Question 5

What are the other organs & tissues in the lymphatic system besides superficial & deep lymph vessels & nodes?

Answer 5

• Thymus
• Bone marrow
• Spleen
• Tonsils
• Peyer patches of small intestine.

Question 6

True or False: Both superficial & deep lymph drainage is symmetric.

Answer 6

False (deep is asymmetric).

Question 7

Where do right upper extremity & thoracic lymphotome drain into?

Answer 7

Right lymphatic duct.

Question 8

Where do left upper extremity, left thoracic lymphotome, both lower extremities, external genital areas, & abdominal lymphotomes drain into?

Answer 8

Left subclavian.

Question 9

True or False: 3/4 of total flow drains to the left subclavian vein.

Answer 9

True.

Question 10

What enhances flow in trunks & ducts?

Answer 10

Respiratory efforts.

Question 11

Which lymph vessels rely on interaction of oncotic & hydrostatic pressures, muscle contraction, arterial pulsation, & gentle movement of skin to absorb & transport lymph fluid?

Answer 11

Superficial lymph vessels.

Question 12

Deeper lymph vessels are generally parallel to which system?

Answer 12

Venous system.

Question 13

What are the smallest lymph vessels called?

Answer 13

Initial lymphatics or lymphatic capillaries.

Question 14

What powers initial lymphs?

Answer 14

Variations in total tissue pressure caused by movement & muscular contraction.

Question 15

What external pressures affect initial lymphs?

Answer 15

Stretch, gravity, & change in position.

Question 16

What happens without changes in total tissue pressure?

Answer 16

Fluid will accumulate in interstitium, leading to edema.

Question 17

What is the term for each segment of collecting lymphatic vessels between valves?

Answer 17

Lymphangion.

Question 18

What do lymph valves prevent?

Answer 18

Backflow.

Question 19

What increases the pumping actions of lymph valves?

Answer 19

• Extrinsic muscle contraction
• Autonomic stimulation
• Manual lymph drainage.

Question 20

True or False: Collecting lymphs form a plexus with several connections between them.

Answer 20

False (does not form plexus, some connections).

Question 21

Lymph trunks have a gradual increase in what?

Answer 21

Diameter size of collecting lymphatics.

Question 22

True or False: Muscle in collecting lymph walls contract arrhythmically.

Answer 22

False.

Question 23

What do smooth muscle cells around the endothelial cell layer of the lymph vessel network face?

Answer 23

Lumen of vessel.

Question 24

How many times per minute does the lymph vessel network contract at rest on average?

Answer 24

5-10 times per minute.

Question 25

What does the pressure inside the vessel reach if many lymphangions contract at once and outflow is obstructed?

Answer 25

100 mm Hg or more.

Question 26

What does sustained high intravascular pressure lead to?

Answer 26

- Ineffective smooth muscle contraction - Vessel failure.

Question 27

What do lymph vessel network walls dilate to prevent closure to?

Answer 27

Valve flaps.

Question 28

What does backflow of lymph distal to the site of obstruction cause?

Answer 28

Lymphedema.

Question 29

Deep lymph vessels are embedded in what type of tissue?

Answer 29

Fatty tissue.

Question 30

What are the four functions of lymph nodes?

Answer 30

- Filter to clean lymph of waste products & cell debris - Adjust fluid concentration - Produce lymphocytes & macrophages - Destroy foreign bacteria, viruses, & cancer cells.

Question 31

Why are lymph nodes often at the sites of obstruction in lymph dysfunction?

Answer 31

Nodes offer 100x normal resistance to flow of lymph within vessels themselves.

Question 32

What is the term for separate territories of lymph?

Answer 32

Watersheds.

Question 33

What are the smaller divisions in territories that designate areas specific to certain regional nodes called?

Answer 33

Lymphotomes.

Question 34

What are the four trunk quadrants?

Answer 34

Left & right: - Axillary territories - Inguinal territories.

Question 35

What are some characteristics of suspicious nodes?

Answer 35

- Changes in size (> 2 cm) - Immobile - Firm or hard - Painless & enlarged.

Question 36

What is lymphangitis?

Answer 36

Inflammation of lymph vessel.

Question 37

What is lymphadenitis?

Answer 37

Inflammation of 1 or more lymph nodes.

Question 38

What is lymphedema?

Answer 38

Increased amount of lymph fluid in soft tissues leading to swelling.

Question 39

What is lymphadenopathy?

Answer 39

Enlargement of lymph nodes.

Question 40

Lymphedema is accompanied by tissue ____________ secondary to chronic inflammation with prolonged swelling.

Answer 40

Fibrosis.

Question 41

What are the stages of lymphedema?

Answer 41

0 (latent) - III (lymphostatic elephantiasis).

Question 42

What do the following causes increase the risk for lymphedema? - Individuals who undergo lumpectomy with ALND or SLND & radiation therapy - Inguinal lymph node dissection to treat melanoma - Prostate cancer after pelvic node dissection - Gyne cancers

Answer 42

Lymphedema.

Question 43

Which type of lymphedema are these etiologic factors associated with?

Answer 43

Primary lymphedema.

Question 44

What is the most common cause of secondary lymphedema worldwide (not in the US)?

Answer 44

- Filariasis - Parasitic worm introduced by mosquito bite in endemic region.

Question 45

What is the most common cause of secondary lymphedema in the US?

Answer 45

Invasive procedures used in diagnosis & treatment of cancer.

Question 46

What are some clinical manifestations of lymphedema?

Answer 46

- Full, heavy, tight sensation in affected body part - Numbness, burning, aching, pain - Decreased flexibility in hand, wrist, or ankle - Loss of skin integrity.

Question 47

Which type of lymphadenitis is characterized by enlarged, tender, warm, & reddened lymph nodes?

Answer 47

Acute lymphadenitis.

Question 48

Which type of lymphadenitis is characterized by scarred lymph nodes with fibrous connective tissue replacement?

Answer 48

Chronic lymphadenitis.

Question 49

What is the term for acute inflammation of subcutaneous lymphatic channels that occurs as a result of strep or staph entering a wound?

Answer 49

Cellulitis.