Wounding and Wound Healing

Question 1

What is the definition of a wound?

Answer 1

Break in the continuity of any body tissue

Question 2

What are the three stages of wound healing?

Answer 2

• Inflammation and debridement
• Proliferation
• Maturation and remodelling

Question 3

What does the inflammatory phase begin with?

Answer 3

• starts with haematosis, first few minutes after injury
• damage to vessels
• blood and lymph escapes
• fills the wound
• cleansing/ prevent further contamination

Question 4

How does haemostasis begin?

Answer 4

• Reflex vasoconstriction (in the first 5-10 mins)
• Reduction in blood loss
• Endothelial damage activates platelets
• Platelet plug then activates vasodilation
• Mast cells release histamine
• Endothelial damage exposes the tissue factor

Question 5

What is the function of a blood clot?

Answer 5

• Haemostatic plug
• acts as a barrier to infection
• Prevents further fluid loss
• Framework for early wound organisation
• Stabilises the wound edges

Question 6

What occurs when a blood clot dries?

Answer 6

Dries to form a scab (eschar)
allows healing to occur underneath
eventually sloughs

Question 7

What occurs in the inflammation and debridement phase?

Answer 7

Migration of leukocytes into the wound
Within 6 hours

Question 8

What is the function of the neutrophils within the wound?

Answer 8

• In 0-48 hours they destroy bacteria
• Vasodilation
• Pro-Inflammatory mediators
• act as a component of pus

Question 9

What is the function of monocytes in the wound?

Answer 9

Essential for wound healing
* transform into activated macrophages
* phagocytose/ destroy bacteria
* remove the clot
* debride necrotic tissue

Question 10

What are the gross signs of inflammation?

Answer 10

• Heat, Redness, Swelling, Pain, Loss of Function

Question 11

What is the ‘big inflammatory focus’?

Answer 11

• Not enough proteins/ Leukocytes to have an inflammatory response in the entire area
• Prolonged pro-inflammatory response

Question 12

What is persistent inflammatory focus?

Answer 12

Prolonged pro-inflammatory phase

Question 13

What are systemic Inflammatory Effects?

Answer 13

Continued vasodilation -> Hypotension
Barrier of the GIT is reduced
Hepatic Inflammation

Question 14

What is the function of the proliferative phase?

Answer 14

Restores skin integrity by filling the wound with new tissue

Question 15

What occurs during fibroplasia?

Answer 15

• Fibroblasts proliferate and migrate into the wound
• differentiation into myofibroblasts
• Migrate along the ECM
• Synthesis of collagen type I
• Requires Oxygen and Nutrition

Question 16

What is angiogenesis?

Answer 16

New capillaries form
* endothelial cells migrate into the ECM
* Capillaries are fragile and highly permeable

Question 17

What is epithelialisation?

Answer 17

• migration of epidermal cells at the margin of the wound
• Proliferation of epidermal cells behind the leading edges
• epidermis comes from wound margins after granulation tissue

Question 18

When is the new epidermis visible?

Answer 18

• large wounds may not be complete
• can be thin and easily traumatised
• adnexal structures do not regenerate
• pigmentation is variable

Question 19

What is the granulation tissue?

Answer 19

Combination of new capillaries, fibroblasts and connective tissue

Question 20

When does wound contraction occur?

Answer 20

days 5-9 post injury
* reduction in wound size
* surrounding skin then stretches
* may be a problem over joints/ body openings
* continues until wound edges meet

Question 21

What is the function of maturation/ remodelling?

Answer 21

• Increases mechanical strength of the wound
• reorganisation of connective tissue
• rearrangement of collagen bundles
• reduction in collagen content

Question 22

How would you manage inflammation?

Answer 22

• Cleaning
• debridement
• protection from further contaminants
• antibiotics if infected