Plastic wound healing Flashcards
What are the stages of wound healing?
4 stages
- Haemostasis
- Inflammation
- Proliferation
- Remodelling
How long does epithelialisation take?
48hrs if 2 pieces of skin are cut and left to heal side by side
What happens during haemostasis?
Vasoconstriction
platelet aggregation
clotting cascade
fibrin deposition
What happens during days 1-4 of wound healing?
Inflammation stage
- chemotaxis attracts neutrophils on days 1 and 2
- macrophages arrive days 2-4
- epithelialisation begins
What happens over the first 3 weeks of wound healing?
Proliferation D4 - wk 3
- fibroblast proliferation
- ongoing angiogenesis
- ongoing epithelialisation
When does remodelling of a wound occur
from week 3 onwards
- collagen synthesis and breakdown occurs
- there is scar contraction
- after 60 days from wound injury the the scar will be at 80% of its pre-injury strength
What are the factors that affect wound healing?
There are local factors and general factors.
Local factors ; blood supply/ischaemia, infection, foreign body, haematoma, mechanical facets e.g. tension, previous radiation
General factors: smoking, chronic disease, steroid use, nutritional deficiencies, age, genetics
What is the difference between primary closure and secondary intention?
In primary closure the 2 edges are left together to heal as linear scar. In secondary intention the edges are not opposed together and the wound heals from the edges in by a combination of epithelialisation and contraction.
Which takes longer, healing by primary closure or secondary intention?
Secondary intention
What are the features of an ideal scar?
Flat
Thin
Colour match
Orientated along the relaxed skin tension lines
Types of abnormal scarring
Hypertrophic and keloid scars
What is the difference between a hypertrophic scar and a keloid scar?
Hypertrophic scars are elevated, red, enlarged scars that form within the borders of the original scar.
Keloid scars are elevated, raised, enlarged scars extending beyond the boundary of the original scar
What is the treatment of abnormal scars
pressure garments
silicone sheeting
steroid injections
re-excision
what skin type is more prone to keloid scar formation?
Darker skin groups
What is the primary goal of wound management?
To obtain a closed wound as quickly as possible to prevent infection and secondary deformity
what is surgical debridement?
Converting a chronic dirty contaminated wound into an acute clean fresh wound
Characteristics of an ideal dressing
Maintain a moist environment at the wound interface
Remove exudate
Act as a barrier to micro-organisms
Be easy to remove without trauma to the wound
Leave no foreign particles in the wound
Steps on the reconstructive ladder
Secondary intention Primary closure Delayed primary closure Skin grafts Local flap Regional flap Free flap
What is a skin graft
Segment of skin detached from its blood supply at the donor site and dependent upon revascularisation from the recipient site
Difference between split and full thickness skin grafts
Split is epidermis and some dermis
Full is all epidermis and dermis
Type of donor healing with a split thickness skin graft
Donor heals by epithelialisation
Type of donor healing with a full thickness skin graft
Donor closed primarily
What type of skin graft is better for large areas?
Split thickness
has less primary contraction
which skin graft is used for face?
Full for face and hends because better cosmesis
What is the purpose of meshing a skin graft?
increases the area the graft can cover and allows evacuation of any fluid that could build up
Factors needed for a graft to take
the graft bed must be
- well vascularise ( not bone, cartilage or tendon)
- good contact ( no haematoma or shearing)
- clean
steps of a graft taking
Adherence
Serum imbibtion
Revasularisation, Inosculation, neovascular ingrowth
Remodelling
A lat dorsi flap is an example of what type of flap
Axial regional
How is a flap different to a graft
A flap is Tissue transferred from one site to another with vascular supply intact ( not reliant on revascularisation from the recipient site like a graft is)
What needs to be checked on a flap post op
Colour Temp Cap refill Soft v tense Doppler
What are the signs of arterial insufficiency post op on a flap
Pale, cool, may or may not have arterial pulse on doppler. Decreased turgor
What are the signs of arterial insufficiency post op on a flap
Purple/ blue
warm of cool
may or may not have doppler arterial pulse
Increased turgor
Contraindications for using VAC dressing
- Exposed vital structure (organ / vessel or vascular graft)
- ongoing infection
- devitalised / alignent tissue
- adhesive allergy
What type of dressing is VAC
A closed system
