Gen Path - Healing and Repair

Question 1

4 steps of healing? (HI,RF,R)

Answer 1

Hemostasis -> Infl. -> Regeneration +-/ Fibrous repair -> Remodelling (aka. organisation)

Question 2

Note: Processes of regeneration and fibrous repair happen simultaneously (and dependent on tissue characteristics)

Question 3

Outline the process of Regeneration (in healing n repair).

Answer 3

1. hemostasis
2. mitosis (to replace dead cells) (esp epithelial)
3. angiogenesis
4. infl. cells (broughtvia blood!) clear out infectious stimuli
5. ECM synthesis (ECM = matrix + fibres)

Question 4

Which tissues/ organs can undergo regeneration? (Name 4: LBSG)

Answer 4

Liver
BM
Skin
GIT

Question 5

Outline the process of fibrous repair.

Answer 5

(see notes on OneNote)

Question 6

2 requirements of collagen synthesis?

Answer 6

Vit C and Zinc

Question 7

What is granulation tissue made up of?

Answer 7

Granulation tissue = a vacular connective tissue made of:
- Vascular capillaries
- Fibroblasts/ myofibroblasts
- mixture of infl. cells

Question 8

Fibroblasts vs Myofibroblasts and both of their common fxn in healing n repair?

Question 9

Explain these local and systemic factors affecting wound healing:

Local:
- Type, size, location of wound
- Local vascular supply
- Secondary infection
- Movement
- Radiation

Systemic:
- Age of patient
- Circulatory status
- Nutrition
- Metabolic status
- Drugs
- Hormones

Question 10

Name 3 complications of wound healing

Answer 10

• atrophic scar (search google for pic n meaning)
• defective scar formation (eg. wound dehiscence and hernias)
• excessive scar tissue formation
• excessive contraction

Question 11

Outline the timeline of cutaneous wounds healing (by primary intention)

Hint:
2 days:
3 days:
5 days:

2 wks:
4 wks:
12 wks:

Answer 11

• Timeline of healing and repair: (healing by primary intention)
  Immediately aft: neutrophil migration

By Day 2: mitosis for epithelial regen

By Day 3: neutrophil replaced by macrophages
+ granulation tissue starts forming

By Day 5: angiogenesis

By 2 weeks: devascularisation

By 4 weeks (1 mth): alot of collagen fibres accum-ed → Scar formed (avascular!)

By 12 weeks (3 mths): complete healing! (resorbed scar)

Question 12

Compare between healing by primary vs secondary intention in terms of:
(i) Wound characteristics
(ii) Process
(iii) Outcome