Chapter 166 - Wound management Flashcards
What are the three phases of wound healing
inflammation/debridement, repair(proliferation) and maturation
In the first 5-10 minutes after a wound occurs, what response happens?
Local vasoconstriction occurs in response to catecholamines and mast cell products to decrease blood loss. Followed by local vasodilation in response to histamine and interleukin-8 allowing plasma and intravascular components to reach extravascular space
Plasma and clotting factors gain access to the wound via damaged blood vessels and are activated to generate what
fibrin (forming a blood clot)
what three phases do neutrophils undergo to gain access to the wound?
margination, attachment, diapedesis
At the wound site, neutrophils release what?
superoxide radicals that kill bacteria and proteinases to degrade necrotic tissue
What cell is more important than neutrophils in wounds? and why?
Macrophages, they produce cytokines that enhance the immune response. They also produce fibronectin and growth factors that stimulate mitosis and are essential for cell proliferation
Duration of the inflammatory phase of wound healing
48-72 hr
What are the four prominent processes in the repair pahse of wound healing?
Angiogenesis, fibroplasia, wound contraction and epithelialization
When is granulation tissue present after a wound occurs?
3-5 days
What type of collagen predominates in wound healing?
INitially type 3, but then type one takes over as the most common type when new fibroblasts fill the wound
When is the height of collagen deposition?
7-14 days after wounding
When should primary closure be pursued?
clean fresh wounds, within 6 hours
When is delayed primary closure performed typically?
within 3 days, prior to the presence of granulation tissue
when does secondary closure occur?
after the onset of granulation tissue, typically 5 days after wounding
What is the optimal lavage pressure for wounds and how is it achieved?
7-8psi using 18-19 g hypodermic needle attached to a 35mL syringe
