Lymph

Question 1

What separates the extravascular interstitial space from the intravascular space?

Answer 1

semipermeable capillary endothelium

Question 2

How does interstitial fluid return to circulation?

Answer 2

via the lymphatic system

Question 3

What are the two main fxns of the lymph system?

Answer 3

fluid handling and immune surveillance

Question 4

How do Starling forces relate to fluid handling?

Answer 4

cause the interchange of fluids between the intravascular and interstitial space

Question 5

What are the three main determinants for filtration?

Answer 5

Net hydrostatic pressure, Net oncotic pressure, Capillary filtration

Question 6

What is the capillary hydrostatic pressure determined by?

Answer 6

blood pressure and specific resistances of local arterioles and venules

Question 7

What is oncotic pressure?

Answer 7

osmotic pressure exerted by proteins in blood plasma…tends to pull water into the circulatory system

Question 8

What is capillary oncotic pressure?

Answer 8

osmotic pressure contributed by plasma proteins (mainly albumin

Question 9

What is the interstitial oncotic pressure?

Answer 9

osmotic pressure contributed by osmotically active proteins in the interstitium

Question 10

Why are oncotic pressures determined by proteins?

Answer 10

because there is no large difference of salt conc btw interstitium and plasma

Question 11

what is the result of increased intravascular hydrostatic pressure?

Answer 11

edema

Question 12

What is the result of decreased intravascular oncotic pressure?

Answer 12

edema (hypoalbuminemia)

Question 13

What causes hypoabluminemia?

Answer 13

low protein intake, not enough protein produced (liver failure), too much protein lost in urine (nephrotic syndrome)

Question 14

When does increased capillary filtration occur?

Answer 14

when endothelium is damaged (burns, inflammation, toxic damage)

Question 15

How does inflammation increase capillary filtration?

Answer 15

can disrupt tight junctions between endothelial cells resulting in swelling

Question 16

What kind of toxic damage can increase capillary filtration?

Answer 16

Sepsis
Pancreatitis
Inhalation injuries

Question 17

What diseases can cause lymphatic obstruction?

Answer 17

lymphoma, metastatic cancers, surgical removal of lymph

Question 18

What are platelets derived from?

Answer 18

megakaryocytes

Question 19

What is the difference btw neutrophils and macrophages?

Answer 19

neutrophils can circulate whereas macrophages reside in tissues. also macrophages are matured monocytes

Question 20

What is the most important fxn of neutrophils and macrophages?

Answer 20

phagocytosis

Question 21

What are the 3 factors that determine whether phagocytosis will occur?

Answer 21

How smooth is it? (rough surfaces increase likelihood of phagocytosis). Protective protein coat? (most native tissues have them, dead tissues and foreign particles are without these coats). Tagged with an antibody or marker (opsonization)? (if so, more likely to be ingested

Question 22

What bacteria has a coat that is resistant to lysosomal digestion and secretes substances that resist killing effects of neutrophils/macrophages?

Answer 22

TB

Question 23

What are histiocytes?

Answer 23

macrophages in skin/sub q

Question 24

What are kupferr cells?

Answer 24

macrophages in the liver

Question 25

What diseases are patients who have asplenia more susceptible to and how should you treat them?

Answer 25

certain types of bacterial pathogens (such as Streptococcus pneumoniae, & Haemophilus influenzae—as these are encapsulated). vaccinate with pneumovax and H. flu

Question 26

What is the walling off effect?

Answer 26

Fibrinogen clots act in interstitial tissues which helps to block fluid flow making it difficult for bacteria to spread

Question 27

What is the left shift?

Answer 27

occurs when neutrophils rise rapidly

Question 28

What substances are most implicated in the feedback control of macrophages/neutrophils?

Answer 28

TNF, IL-1, GM-CSF, G-CSF, M-CSF (colony stimulating factors)

Question 29

What is in exudate?

Answer 29

necrotic tissue, dead neutrophils, dead macrophages, and tissue fluid