Wound Healing Flashcards
What are the three phases of wound healing?
Inflammatory, proliferative, maturation
Inflammatory phase of healing
Injury to day 4 post injury.
Vasoconstriction –> fibrin blood clots –> vasodilation –> neutrophils, macrophages –> removal of bacteria and debris
Cardinal Signs of inflammation
Rubor et tumor cum calore et dolore (redness and swelling with warmth and pain)
Proliferative phase duration
Day 4-21 days post injury
Proliferative phase chain of events
Macrophages stimulate growth factors for:
endothelial cells –> new blood vessel growth*
fibroblasts –> collagen*
epithelial cells –> re-epithelialization
*leads to granulation tissue
What are growth factors?
Proteins that affect the proliferation, movement, maturation and
biosynthetic activity of cells.
Hypergranulation tissue
Too much oxygen can cause this. Too much granulation tissue, can make a mound and cause epibole, skin can’t grow over it.
Maturation phase duration
21 days to 2 years post injury
Maturation phase chain of events
collagen, deposition, remodeling, increase tensile strength, scar reduction.
Balance between scar forming and scar remodeling.
What happens if you have too much lysis in maturation phase/with remodeling?
Chronic wound
What happens if you have too much synthesis in maturation phase/with remodeling?
Keloid
3 R of immature scar
Red, raised, rigid
3 P’s of mature scar
Pale, planar, pliable
Keloid Scarring
Too much synthesis and not enough lysis. Keloid scarring extend BEYOND the boundaries of the original injury which is what differentiates it from hypertrophic scarring. More likely in people with more pigmentation.
Epithelialization
RE-epithelialization occurs from migrating epithelial cells, may migrate from the side, from viable epithlial cells lining epidermal appendages (hair follicles). Without remaining epidermal appendages, will need skin graft..
