Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
27 Cards in this Set
- Front
- Back
|
What are they two types of wound healing?
|
regneration (regrowth)
repair |
|
|
What is regeneration?
|
regrowth
normal tissue develops normal histological character Normal function healing replavement with original form and funciton uncommon in normal circumstances |
|
|
What is repair?
|
scar tissue
binds wound edges together altered function decrease strength compared to unwounded tissue |
|
|
What are the phases of wound healing?
|
inflammatory (lag)
-hemostasis -inflammation debridement proliferative -repair remodeling -maturation |
|
|
What is the inflammatory phase of wound healing?
|
-hemostasis
-inflammation debridement blood vessel constricution platelets important in initiating wound healing coagualtion - fibrin clot inflammatory mediator activation |
|
|
What are inflammatory mediators in the inflammation phase of wound healing?
|
platelets activating factor from neutrophils, basophils, enothelial cells and platelets - helps for platelete aggregation and vasodilation
platelet factor 4 - heparin like products TGF-B chemotactic for monocytes and stimulates generation of endothelium and vascular smooth muscle |
|
|
What is the debridement phase of wound healing?
|
begins 6-12 hours after wound
see migration of inflammatory cells into wound neutrophils predominate for first 2-3 days blood borne monocytes become macrophages withing 24-48 hours |
|
|
What are functions of macrophages?
|
growth factor functions
-PDGF - angiogenesis -IGF-insulin growth factor - nerve, muscle and skin stimulation for growth -TGF-B- regulate cell cycle Cytokines TNF-a - induces NO proliferation -stimulates fibroblasts -initiates a cytokine casecade that increases vascular permeability -IL 1,6,8 |
|
|
What do acute phase proteins do?
|
increase opsinization of microbes
bind free iron so unavailable to microbes inhibit plasmin and thrombin increase coagulation activate complement cascade recruit other immune cells to site |
|
|
What is the inflammation phase duration?
|
patient condition
based on delivery of O2 and nutrients to tissues local wound environment -bacteria devitalized foreign bodies **want to keep this phase short |
|
|
What is the proliferative phase?
|
begins 2-5 days after wounding
angiogenesis firbroblasts appear in the wound collagen production begins wound tensile strength increase |
|
|
What can enhance wound healing?
|
topical wound medication
ideal would dressings (possible) negative pressure wound therapy hyperbaric O2 |
|
|
what is negative wound pressure therapy?
|
used for acute wounds
stimulates healing by suction removes debris and decreases the bacterial burden promote granulation tissue decreases inflammation increase proliferation phase decreases bandage changing |
|
|
What is hyperbaric oxygen?
|
see in humans mostly but in some vet practices
can produce free radicals (decrease wound jealing) improves local deliver of O2 to tissues stimulate granulation tissue formation of bone (cortical fenestration (forage) |
|
|
What is the remodeling phase?
|
blood vessel remodeling
collagen maturation and remodeling wound tensile strength |
|
|
What are factors that affect wound healing?
|
species
wound depth/location dogs and cats - no differences in healing of sutured wounds removal of sub-q tissue slows second intention healing |
|
|
What are local factors affecting wound healing?
|
surgical technique*
blood supply infection mechanical stress foreign bodies topical medications |
|
|
What are systemic factors affecting wound healing?
|
Age
nutritional status* concurrent disease anemia hypovolemia drugs |
|
|
What are reasons for non healing wounds?
|
immunodeficiency
foreign bodies DM hyperadrenocortisism drugs nutritional status |
|
|
What are the wound healing classification?
|
first intension
second intension third intension |
|
|
What is first intention wound healing?
|
primary wound closure, minimal inflammation
delayed primary wound closure |
|
|
What is second intention wound healing?
|
healing by contraction and epithelialization
|
|
|
What is third intention wound healing?
|
secondary wound closure
wound is closed after granulation tissue forms |
|
|
What is cessation of wound contraction?
|
wound has healed
tension in surrounding skin exceeds pull of myofibroblasts collagen deposition in chronic wound interferes with pull of myofibroblasts |
|
|
What are complications of second intension healing?
|
thin tissues
susceptible to trauma may need grafting |
|
|
What is wound contrature
|
scar that interferes with normal function
need to release contracture so it can heal normally |
|
|
What is the second wound effect?
|
second surgical approach made through previous incision before repair phase is complete
-incisional hernia repair -intussusception after prior abdominal surgury if tissue is healthy do not freshen the edges-tissues are already primed for wound healing to proceed |
