Microcirculation Flashcards Preview

Fundies First Module--First Exam > Microcirculation > Flashcards

Flashcards in Microcirculation Deck (24):
1

nutrient and waste exchange occurs because of/by

diffusion--through/btwn capillary ENDOTHELIAL cells

2

diffusion based on

pressure within/out

3

proteins in vascular system generally

remain within system and contribute to oncotic pressure

4

arterial capillary hydrostatic pressure tends to

promote FILTRATION across capillary wall

5

oncotic pressure tends to promote

filtration from arterial side and
reabsorption by venous side

6

interstitial fluid osmotic pressure is generally lower

than oncotic pressure

7

lymphatic capillaries are formed by

single layer of endothelial cells with fenestrated basement membrane for movement of interstitial fluid and large particles

8

stationed along the lymphatic vessels

lymph nodes

9

immune system cells in lymphnodes

sample lymph gathered from tissues

10

pathophysiology of lymph system

1. lymph edema--damage to normal lymph channels
2. lymphatic cancer spread--can spread locally (i.e melanoma) or globally
3. lymphadenitis
4. lymphoma

11

knowing lymph drainage in relation to cancer will

instruct where to look for tumors around known tumor site--surgeons may remove surrounding lymph nodes when removing cancer

12

most common cause of lymph edema worldwide

Filariasis--worm that infiltrates lymphnodes causing inflammation-->obstruction

13

alarming for lymph cancer

large, very firm, NONTENDER nodes

14

press deeply on swollen extremity with finger--stays depressed

pitting edema

15

blood flow to capilaries relates to

precapillary sphincter status (contracted vs. relaxed)

16

greatly controls capillary function

autonomic NS -- Alpha 1 adrenergic receptors

17

Ex. of vasoactive substances and hormonal control

1. epinephrine--may inject with lido to decrease blood flow
2. histamine-->bradykinins
3. serotonin--vascular spasm
4. prostaglandins--vasoconstriction or vasodilation
5. nitric oxide--vasodilator

18

* substance made by endothelial cells for purpose of vasodialtion

nitric oxide

19

decreased O2 to capillaries

dilates capillary beds--except in lungs

20

lung capilaries _____ with decrease in O2

constrict--imp. increases blood flow to healthy or unobstructed (mucos/fluid buildup) lung spots--trouble with COPD pt's (leads to RIGHT VENTRICULAR hypertrophy) (hypoxic pulmonary vasoconstriction)

21

the maintenance of constant blood flow to an organ despite changing arterial pressure

AUTOREGULATION of organ blood flow

22

autoregulation of organ blood flow may be due to_____________ or _____________

1. Myogenic hypothesis--smooth muscle contraction when stretched
2. metabolic hypothesis--vasodilation upon buildup of metabolic byproducts i.e. CO2, H+, lactate

decrease in flow will lead to vasodilation

23

cerebral blood flow normal

50-150 mmHg -- related to autoregulation or organ systems

24

capillary dilation when

low pH, high CO2, histamine--except in lungs (opposite)