Week 2: Wound Healing (Ch 2)

Question 1

What are the 3 phases of healing?

Answer 1

1. Inflammation
2. Proliferation
3. Maturation and Remodeling

Question 2

What are the cardinal signs of inflammation?

Answer 2

Swelling (Tumor)
Redness (Rubor)
Warmth (Calor)
Pain (Dolor)
Decreased Function (Functio Laesa)

Question 3

What happens in the first vascular response?

Answer 3

• transudate produces localized edema
• blood vessels constrict to reduce blood loss
• platelet aggregation
• activated platelets release chemical mediators

Question 4

Which chemical mediators do activated platelets release and what do they do?

Answer 4

Cytokines: signal proteins
Growth Factors: cell growth and differentiation
Chemotactic Agents: attract cells for wound repair

Question 5

What happens in the second vascular response?

Answer 5

Vasodilation within 30 minutes of injury, exudate formation, histimine release, and prostaglandin release

Question 6

What does histamine release do?

Answer 6

increased vessel wall permeability, short term vasodilation

Question 7

What does prostaglandin release do?

Answer 7

long term vasodilation

Question 8

What cells are involved in the cellular response of inflammation?

Answer 8

platelets, PMNs, fibroblasts, macrophages, mast cells

Question 9

What are the main stages of Inflammation?

Answer 9

Vascular responses 1 and 2

Cellular response

Question 10

What are the first white blood cells to reach the site of injury? What do they do?

Answer 10

Polymorphic Neutrophils

Diapedesis, Margination, and Chemotaxis

Question 11

Which cells are very specific in their activity?

Answer 11

OMNs

Question 12

What do macrophages do?

Answer 12

enhance inflammatory processes, clean up

Question 13

What do mast cells do?

Answer 13

enhance inflammatory processes

Question 14

What are the main stages of the Proliferation phase?

Answer 14

Angiogenesis
Granulation Tissue formation
Wound contraction
Epithelialization

Question 15

Which phase of proliferation do angioblasts act in? What do they do?

Answer 15

Angiogenesis

forms new blood vessels

Question 16

Which phase of proliferation do fibroblasts act in? What do fibroblasts do?

Answer 16

Granulation tissue formation

Builds granulation tissue

Question 17

Which phase of proliferation do myofibroblasts act in?

Answer 17

Wound contraction

Question 18

Which phase of Proliferation do keratinocytes act in?

Answer 18

Epithelialization

Question 19

Which cells act in granulation tissue formation?

Answer 19

Matrix metalloproteases (MMPs), integrins

Question 20

What happens during the maturation and remodeling phase of healing?

Answer 20

• New collagen synthesis
• Old collagen broken down by collagenases
• Reorientation of collagen fibers

Question 21

How long might maturation and remodeling continue?

Answer 21

up to 2 years after wound closure

Question 22

What is it called when the edges of the wound can be physically approximated?

Answer 22

Primary closure

Question 23

What is it called when granulation tissue must be produced to full the wound defect before epithelialization and wound closure can occur?

Answer 23

Secondary closure

Question 24

How long should it take a wound to close by primary closure?

Answer 24

1-14 days

Question 25

How long does it take a wound to heal by secondary closure?

Answer 25

``` acute = within 2 weeks chronic = within 30 days ```

Question 26

What happens in delayed primary closure (tertiary)?

Answer 26

wound is cleaned and observed for signs of infections... typically kept open with a wound vac for some reason... then closed with sutures and should heal within 1-2 weeks of suturing

Question 27

What can cause chronic wounds?

Answer 27

- senescent cells - higher levels of MMPs - lower levels of TIMPs - greater numbers of inflammatory cytokines and chronic wound cells - arrested curent of injury

Question 28

What can cause chronic inflammation?

Answer 28

- presence of foreign body in wound bed - repetitive mechanical trauma - cytotoxic agents

Question 29

What else is abnormal when it comes to wound healing?

Answer 29

absence of inflammation, hypertrophic scarring, keloids, contractures, dehiscence

Question 30

What can cause hypogranulation or nonadvancing wound edge?

Answer 30

hypogranular wound, epibole