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Flashcards in Lymph Deck (29):
1

What separates the extravascular interstitial space from the intravascular space?

semipermeable capillary endothelium

2

How does interstitial fluid return to circulation?

via the lymphatic system

3

What are the two main fxns of the lymph system?

fluid handling and immune surveillance

4

How do Starling forces relate to fluid handling?

cause the interchange of fluids between the intravascular and interstitial space

5

What are the three main determinants for filtration?

Net hydrostatic pressure, Net oncotic pressure, Capillary filtration

6

What is the capillary hydrostatic pressure determined by?

blood pressure and specific resistances of local arterioles and venules

7

What is oncotic pressure?

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

8

What is capillary oncotic pressure?

osmotic pressure contributed by plasma proteins (mainly albumin

9

What is the interstitial oncotic pressure?

osmotic pressure contributed by osmotically active proteins in the interstitium

10

Why are oncotic pressures determined by proteins?

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

11

what is the result of increased intravascular hydrostatic pressure?

edema

12

What is the result of decreased intravascular oncotic pressure?

edema (hypoalbuminemia)

13

What causes hypoabluminemia?

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

14

When does increased capillary filtration occur?

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

15

How does inflammation increase capillary filtration?

can disrupt tight junctions between endothelial cells resulting in swelling

16

What kind of toxic damage can increase capillary filtration?

Sepsis
Pancreatitis
Inhalation injuries

17

What diseases can cause lymphatic obstruction?

lymphoma, metastatic cancers, surgical removal of lymph

18

What are platelets derived from?

megakaryocytes

19

What is the difference btw neutrophils and macrophages?

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

20

What is the most important fxn of neutrophils and macrophages?

phagocytosis

21

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

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

22

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

TB

23

What are histiocytes?

macrophages in skin/sub q

24

What are kupferr cells?

macrophages in the liver

25

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

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

26

What is the walling off effect?

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

27

What is the left shift?

occurs when neutrophils rise rapidly

28

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

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

29

What is in exudate?

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