Wound Healing

Question 1

What are the phases of wound healing?

Answer 1

• hemostasis
• inflammation
• proliferation
• remodeling (maturation)

Question 2

What is the timeframe of each phase of wound healing?

Answer 2

• hemostasis: < 1 hour
• inflammation: 4-6 days
• proliferation: 4 - 24 days
• remodeling (maturation): 21 days - 2 years

Question 3

What cells peaks during the inflammation phase?

Answer 3

Neutrophils

Question 4

What cells peaks during proliferation phase?

Answer 4

macrophages

Question 5

What cells occur during maturation?

Answer 5

• Fibroblasts
• Lymphocytes

Question 6

What does hemostasis initiate?

Answer 6

wound healing cascade

Question 7

What is the tissue injury cascade?

Answer 7

• Platelet activation
• Activation of clotting cascade
• Complement cascade (fibrinogen –> fibrin)
• Release of chemicals that promote inflammation

Question 8

What is the main function of hemostasis?

Answer 8

coagulation & secretion of growth factors

Question 9

What are the 3 stages of the inflammatory phase of wound healing?

Answer 9

• Vascular stage
• Exudate stage
• Reparative stage

Question 10

What occurs during the vascular stage of the inflammatory phase?

Answer 10

• Hyperemia
• 5 cardinal signs of inflammation

Question 11

What is hyperemia?

Answer 11

excess blood in vessels supplying an organ or other part of the body

Question 12

What are the 5 cardinal signs of inflammation?

Answer 12

• Edema
• Loss of function
• warmth
• redness
• pain

Question 13

What is included in the exudate stage of the inflammatory phase?

Answer 13

• serous
• purulent
• fibrinous
• hemorrhagic

Question 14

What does serous wound mean?

Answer 14

clear fluid like what may be seen in a blister

Question 15

What does purulent wound mean?

Answer 15

pus which means infected

Question 16

what does fibrinous wound mean?

Answer 16

fiber inside

Question 17

what does hemorrhagic wound mean?

Answer 17

bleeding

Question 18

what occurs in the reparative stage of the inflammatory phase?

Answer 18

phagocytosis with true wound healing beginning

Question 19

what is the main function of the inflammatory phase?

Answer 19

remove debris

Question 20

during the inflammatory phase of wound healing how does an increase in vascular permeability and vasodilation increase?

Answer 20

mast cells do this via degranulation and production of histamines

Question 21

During the inflammatory phase what does an increase in vascular permeability and vasodilation allow?

Answer 21

allows for neutrophils & macrophages to migrate

Question 22

During the inflammatory phase of wound healing what cells promote growth & migration of cells for tissue repair?

Answer 22

• neutrophils
• macrophages
• accumulation of lymphocytes

Question 23

During the inflammatory phase of wound healing what does neutrophils, macrophages and accumulation of lymphocytes do?
When does the highest number present?

Answer 23

• cleanse wound of debris
• highest number present within 24-48 hours after injury

Question 24

During wound debridement of the inflammatory phase what proteins break down damaged tissue?

Answer 24

Proteinases & collagenases

Question 25

What occurs during the proliferative phase of wound healing?

Answer 25

- granulation - angiogenesis - contration - epithelialization

Question 26

What is granulation during the proliferative phase of wound healing?

Answer 26

development of new tissue (want to protect this at all costs)

Question 27

What is angiogenesis during the proliferative phase of wound healing?

Answer 27

blood vessel formation

Question 28

What is wound contraction during the proliferative phase?

Answer 28

edges of the wound contract to make the damaged area smaller

Question 29

What is wound epithelialization during proliferative phase?

Answer 29

development of the epidermis

Question 30

What is the main function of the proliferative phase of wound healing?

Answer 30

- fibroblasts produce collagen & epithelial tissue covers the wound - fill & cover - heals from edge towards center

Question 31

What cell is involved in degradation of non-viable tissue during the proliferative phase?

Answer 31

macrophages

Question 32

What cells are involved in neovascularization during the proliferative phase?

Answer 32

- macrophages (a little) - endothelial cells (capillary formation)

Question 33

What cell is involved in collagen/extracellular matrix production during the proliferative phase?

Answer 33

fibroblasts

Question 34

What cell is involved in wound contracture during the proliferative phase?

Answer 34

myofibroblasts

Question 35

What cell is involved in epithelialization during the proliferative phase?

Answer 35

epithelial cells (basal epidermal cells)

Question 36

What occurs during the remodeling phase of wound healing?

Answer 36

- organization of collagen tissue into more definitive & finite pattern - increase in tensile strength (scar tissue)

Question 37

How strong can scar tissue become?

Answer 37

only about 80% of regular tissue

Question 38

How long does the remodeling phase of wound healing last?

Answer 38

2 wks - 2 years

Question 39

What is the main function of the remodeling phase of wound healing?

Answer 39

remodeling of tissue & increasing its tensile strength

Question 40

During the remodeling phase of wound healing collagen mature, what type of collagen increase?

Answer 40

Type I collagen and some type III

Question 41

Initially collagen fibers are laid down haphazardly, what happens to the fibers during the remodeling phase?

Answer 41

- Fibers align & new collagen is laid down along lines of stress to increase tensile strength of scar

Question 42

T/F: New tissue is prone to injury

Answer 42

true

Question 43

T/F: Collagen is constantly turning over

Answer 43

true

Question 44

What is healing by primary intention?

Answer 44

Edges brought together & held there by mechanical means

Question 45

What is the preferred method of healing?

Answer 45

healing by primary intention

Question 46

When does healing begin if healing by primary intention?

Answer 46

2-3 days

Question 47

What are the benefits of healing by primary intention?

Answer 47

- decrease risk of infection - decreased time to heal - minimal scar formation

Question 48

What is the difference between a separated or dehiscence suture?

Answer 48

- separated if < 1 cm - Dehiscence if > 1 cm

Question 49

What is healing by secondary intention?

Answer 49

gradual filling of the wound with granulation tissue

Question 50

When is healing by secondary intention used?

Answer 50

large surface areas with retracted edges or when large amounts of tissue have been lost

Question 51

What are the cons of healing by secondary intention?

Answer 51

- more easily infected - increased healing time - increased scar formation

Question 52

What is healing by delayed primary (tertiary) intention?

Answer 52

large wounds can be partially closed w/ retaining sutures or tension sutures

Question 53

Healing by delayed primary (tertiary) intention is used when?

Answer 53

- approximating the edges puts too much strain on the periwound skin & subcutaneous tissue - concern for infection & drainage that needs to be removed to prevent abscess formation