Wounds 2

Question 1

Healing by Primary Intention

Answer 1

• Clean surgical wounds or recent traumatic wounds, minor injuries
• Stitched or glued or allowed to heal alone
- stitching is to bring deeper tissues together. Glue is used for higher layers towards the surfaces. Can also use staples which are very effective

Question 2

Healing by Primary Intention (1)

Answer 2

• Acute inflammation (within a few minutes of injury and lasts for approx 3 days)
• Platelets flow into wound
• Thromboplastin liberated
• Vasodilation results in serum being released into wound
• Neutrophils and macrophages “clean” wound

Question 3

Healing by Primary Intention (2)

Answer 3

• Fibroblasts responsible for synthesis of collagen
• Scab formed within a few hours
• Within 2‐3 days epithelial cells begin to grow
across the wound under the scab
• Complete healing within 2‐3 weeks

Question 4

Healing by Secondary Intention

Answer 4

Wound too large or “dirty” for closure 
• Necrosis (not always present)
• Granulation
• Vascularisation
• Epithelialisation

eg, pressure sores, big grazes, burns - where you have no skin surface closed up

Question 5

Necrosis (dead tissue)

Answer 5

• Dry, necrotic tissue (no nerve sensation so doesn't hurt)
– Eschar
• Wet, necrotic tissue
– Slough
• Tissue stuck to wound bed 
• Must be debrided (removed)

if it is not removed more likely to get infected and spread

Question 6

Granulation

Answer 6

• Inflammation
• Infiltration with erythrocytes, leukocytes and platelets
– “Exudate”
• Endothelial cells appear as capillary buds
• Growth factors generated which promote capillary formation

as wound gets better it changes from red to pink

Question 7

Epithelialisation

Answer 7

• Occurs once the wound cavity has filled with granulation tissue
• Epithelium around wound edges become active and begin to grow across wound
• Wound then begins to contract noticeably

big wounds shrink 3-4 weeks after

Question 8

Properties of Dressings

Answer 8

Dressings should ensure that the wound remains:
• Moist with exudate but not macerated
• Free of clinical infection and excessive slough
• Free of toxic chemicals, particles or fibres released by the dressing
• At the optimum temperature for healing to take place
• Undisturbed by frequent or unnecessary dressing changes
• At an optimum pH value (dressing pH should be neutral to the body)

(Steve Thomas, Director Surgical Materials Testing Laboratory, Brigend)