2. Principles of Healing Flashcards
What are the phases of wound healing?
- inflammatory phase
- proliferative phase
- maturation phase
what are some mechanisms of wound repair?
- CT deposition
- epithelialization
- contraction
what is the inflammatory phase characterized by/
hemostasis and inflammation –> stabilize the wound thru clot formation
What is the first response cell in the inflammatory phase? what is the secondary response cell?
platelets- 1st response cell
neutrophils- 2nd response cell
what cell type stimulates fibroblasts (collagen) and angiogenesis?
TNF
what is the most essential cell for wound healing?
macrophages
inflammatory phase
what unique things occur in the proliferative phase?
epithelization
angiogenesis
collagen deposition
describe the orientation of collagen in the proliferative phase vs. the maturation phase.
collagen is oriented randomly in the proliferative phase compared to being more organized in the maturation phase
in which phase does wound contraction occur?
maturation phase
what is the time scale for each phase of healing?
inflammatory phase- 3 days
proliferative phase- 2 wks
maturation phase- a few weeks to a year
what is the relationship of tissue thickness compared to tensile strength?
(inversely related) - collagen is unorganized and tissue is thick (tensile strength is low) but as maturation phase occurs, collagen becomes more organized and tensile strength increases
what is the most important factor that affects wound healing?
blood supply
what are the guiding principles of wound healing?
- vascular perfusion
- bacterial balance
- nutritional balance
- control contributing factors
what is closure by primary intention?
side to side closure of the wound with sutures
*reapproximation of skin edges
what is closure by secondary intention?
wound is left open to granulate to closure
what is delayed primary closure?
wound is left open for a period of time and then primarily closed
what is the primary event in a primary intention closure?
CT deposition
no contract, no epithelization
what is the primary event in a closure by secondary intention?
contraction
yes CT deposition, and some epithelization
what is the primary event in a partial thickness wound (very superficial)?
epithelization
no contract, no CT deposition
what is the name of the scar that extends beyond the boundary of the original skin injury?
keloid
what is the name of the scar that is within the boundary of the original skin injury?
hypertrophic scar
what areas of the body are susceptible to keloid?
sternum, deltoid area, upper back have increased susceptibility bc they have elevated levels of muscle and skin tension
what is the recurrence rate of keloid?
50%
