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Phase 2a - Introductory Clinical Sciences > Inflammation and Healing > Flashcards

Flashcards in Inflammation and Healing Deck (94)
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1

define inflammation

local tissue response to injury

2

name some beneficial effects of inflammation

Destruction of invading microorganisms.
Walling off of an abscess cavity - preventing spread of infection.

3

give examples of how inflammation may cause disease

An abscess in brain = space-occupying lesion, compressing surrounding structure.
Fibrosis from chronic inflammation - distort tissues, alter function.

4

define acute inflammation

the initial and often transient series of tissue reactions to injury

5

define chronic inflammation

subsequent and often prolonged tissue reactions following the initial response

6

what type of cell is characteristically recruited in acute inflammation?

neutrophil polymorph

7

list the possible outcomes of acute inflammation

suppuration (e.g. abscess)
organisation
progression to chronic inflammation
resolution

8

what is the vascular component of acute inflammation?

dilatation of vessels

9

what is the exudative component of acute inflammation?

vascular leakage of protein-rich fluid

10

list the causes of acute inflammation

microbial infections;
hypersensitivity reactions;
physical agents;
chemicals;
bacterial toxins;
tissue necrosis (e.g. ischaemic infarction)

11

name some physical agents that may cause acute inflammation

trauma; ionising radiation; heat; cold

12

name some chemical agents that may cause acute inflammation

corrosives; acids; alkalis; reducing agents

13

describe how a microbial infection causes acute inflammation

viruses - death of individual cells by intracellular multiplication.
bacteria - release of exotoxins/endotoxins

14

how does a hypersensitivity reaction cause acute inflammation?

inappropriate/excessive immune reaction damages tissues

15

define tissue necrosis

death of tissues from lack of oxygen/nutrients resulting from inadequate blood flow (infarction)

16

what are the macroscopic appearances of acute inflammation?

redness - rubor
heat - calor
swelling - tumor
pain - dolor
loss of function

17

what causes redness/rubor in acute inflammation?

dilatation of small blood vessels within the damaged area

18

what causes the heat associated with inflammation of peripheral parts of the body?

increased blood flow (hyperaemia) through the region - vascular dilatation and delivery of warm blood

19

what causes swelling associated with acute inflammation?

oedema - accumulation of fluid in extravascular space as part of fluid exudate.
also physical mass of inflammatory cells.

20

what causes the pain associated with acute inflammation?

stretching/distortion of tissues due to oedema.
pus under pressure in an abscess cavity.
chemical mediators (bradykinin, prostaglandins, serotonin)

21

what causes loss of function in acute inflammation?

movement of inflamed area is consciously and reflexly inhibited by pain.
severe swelling may limit movement.

22

If there are neutrophil polymorph's present, is it acute or chronic inflammation?

acute

23

what are the three processes involved in acute inflammation?

1. changes in vessel calibre and flow
2. increased vascular permeability and formation of fluid exudate
3. formation of cellular exudate - migration of neutrophil polymorphs into extravascular space

24

describe the changes in vessel calibre seen in acute inflammation

dilatation of arteriole
opening of pre-capillary sphincter
most capillaries full of blood

25

give some examples of chemical mediators that increase vascular permeability in acute inflammation?

histamine
bradykinin
nitric oxide

26

what is exudation?

net escape of protein-rich fluid from blood vessels

27

what proteins are present in the fluid exudate seen in inflammation?

immunoglobulins
coagulation factors - fibrin deposition

28

describe the process of neutrophil polymorph migration into tissues in acute inflammation

1. margination of neutrophils
2. pavementing of neutrophils
3. pass between endothelial cells
4. pass through basal lamina and migrate into adventitia

29

what is the main source of histamine?

mast cells, stored in granules in their cytoplasm

30

what stimulates histamine release?

C3a and C5a
lysosomal proteins released from neutrophils