Surgical wounds

Question 1

What are the main types of wound healing?

Answer 1

• Primary and secondary intention
• Four stages to both types:
  
  • Haemostasis
  • Inflammation
  • Proliferation
  • Remodelling

Question 2

Describe primary intention healing?

Answer 2

• Occurs in wounds with edges that are close together (scalpel incision)
• Faster than secondary intention
• Complete return to function with minimal scarring

Question 3

Describe the steps of primary intention healing in more detail?

Answer 3

• Haemostasis
  
  • Platelets and cytokines form haematoma and induce vasoconstriction to limit blood close
  • Scab protects wound from infection
• Inflammation
  
  • Inflammatory response removes cell debris and pathogens
• Proliferation
  
  • Cytokines form inflammatory cells drive proliferation and formation of granulation tissue. VEGF induces angiogenesis.
• Remodelling
  
  • Devascularisation of the region and apoptosis of fibroblasts

Question 4

Describe surgical wound healing?

Answer 4

• Wound from a scalpel will heal by primary intention
  
  • Healing is aided by surgical glue, sutures or staples
• Sutures:
  
  • Too loose => wound edges not opposed which limits primary healing
  • Too tight => blood supply to the region can be compromised => necrosis

Question 5

Describe secondary intention healing?

Answer 5

• When sides of wound are not opposed
• Healing occurs from the bottom of the wound upwards

Question 6

Describe the stages of secondary intention healing in more detail?

Answer 6

• Haemostasis
  
  • Large fibrin mesh forms which fills the wound
• Inflammation
  
  • Inflammatory response removes debris and pathogens (more intense reaction than primary intention healing)
• Proliferation
  
  • Granulation tissue forms from bottom to top of wound
  • Then covered with epithelium
• Remodelling
  
  • Inflammation resolves and wound contraction occurs from myofibroblasts

Question 7

Describe the role of myofibroblasts in wound healing?

Answer 7

• Vital in secondary intention wound healing
• Modified smooth muscle cells that contain actin and myosin
  
  • Act to contract the wound during remodelling
• Can also deposit collagen for scar healing

Question 8

Describe a complication that can occur in wound healing?

Answer 8

• Keloid scarring
  
  • particularly in people with darker skin
  • excessive collagen production
  • occurs in both primary and secondary intention healing

Question 9

What are the local factors which can reduce wound healing?

Answer 9

• Type, size and wound location
• Local blood supply
• Infection
• Radiation damage

Question 10

What are the systemic factors which can reduce wound healing?

Answer 10

• Increasing age
• DM
• Nutritional deificencys (especially vitamin C)
• Obesity

Question 11

What are the basic principles for the management of a wound?

Answer 11

• Haemostasis
• Cleaning of the wound
• Analgesia
• Skin closure
• Dressing and follow-up advice

Question 12

What steps can be taken to reduce bleeding and assist haemostasis?

Answer 12

• Pressure
• Elevation
• Tourniquet
• Suturing

Question 13

What are the aspects of wound cleaning?

Answer 13

• Disinfect with antiseptic
• Decontaminate
• Debride
• Irrigate with saline
• Antibiotics if high risk wound or infection signs

Question 14

What are the main methods of skin closure of a wound?

Answer 14

• Skin adhesive strips
• Tissue adhesive glue
• Sutures
• Staples

Question 15

Describe the dressing of a wound?

Answer 15

• 1st layer:
  
  • Non-adherent (saline soaked gauze)
• 2nd layer
  
  • Absorbent material
• Top layer:
  
  • Soft gauze tape

Question 16

What is often a prelude to surgical wound infection?

Answer 16

Haematoma

Question 17

What is dehiscence?

Answer 17

When a surgical incision reopens internally or externally

Question 18

What is evisceration?

Answer 18

Extrusion of the abdominal visceral through a complete abdominal wound dihiscence