IntroSx1- SA Wound Mgmt

inflammation--> repair--> maturation

injury--> bleeding--> vasoconstriction for 5-10min--> [inflammatory phase] platelet activation--> vasodilation--> increased vascular permeability and transudation--> [repair phase] blood clot and provisional ECM formation of fibrin and fibronectin--> proliferative phase and formation of granulation tissue--> [maturation phase] collagen reorganization for scar formation

• provisional matrix: blood clot of fibrin and fibronection
• proliferative phase: granulation tissue of collagen, hyaluronan, laminin, and proteoglycans
• maturation phase: scar with reorganization of collagen (not as strong as original tissue, but better than the first two)

• inflammation and debridement by inflammatory cells
• Begins with leukocyte migration promoted by ECM formation; mostly neutrophils at first, then macrophages come to debride and clean up wound
• Macrophages also send signals to fibroblasts to migrate and start repair phase

Healthy, functioning macrophages

• when fibrinolysis occurs and breaks down the fibrin clot and fibroblasts are very slowly moving in to produce collagen
• this is most significant in sutured wounds

lag phase of the inflammatory phase

• lag phase of inflammatory phase- weakest
• repair stage- intermediate strength
• maturation phase- strongest (but never normal)

Proliferation: angiogenesis and fibroplasia (new blood vessels, recruitment of fibroblasts)--> GRANULATION TISSUE--> epithelialization, wound contraction

during the repair phase, the endothelial sprouting, chemotaxis and mitogenic mediators recruit fibroblasts; oxygen tension and lactic acid levels are different in a wound than healthy tissue, which promotes new blood vessels sprouting

mesenchymal cells, such a fibroblasts and myofibroblasts, come in to deposit collagen and produce proteoglycan so the wound becomes stronger

• contains myofibroblasts, which cause wound contraction
• capillaries are perpendicular to surface of wound
• fills the tissue defect
• protects wound
• barrier to infection
• scaffold for epithelialization

• mobilization and migration of cells on the outside, which proliferate and grow new skin on the surface of the wound
• occurs UNDERNEATH the scab, from the wound edge, inward

• reduction in size of wound by myofibroblasts
• surrounding skin stretches
• in areas of joints, contracture occurs (abnormal function of joint or muscle)
• skin stops growing/ contracting due to contact inhibition (when it touches the other wound edge, it knows the wound is healed)

MMPs and TIMP are key in signaling cell death/ stopping the process after adequate wound healing

when wound edges are already apposed, epithelialization can start within 24-48 hours

• wound contraction and epithelialization (second intention and granulation tissue)
• adnexal structures don't regenerate (scars are hairless)

Cats heal slower, produce less granulation tissue, when cats finally heal they have faster contraction

• Clean: no hollow viscous entered, atraumatic (incision)
• Clean contaminated: operative wounds of a contaminated organ system, no break in technique
• Contaminated: open traumatic wounds, operative wounds with break in technique
• Dirty: old traumatic wounds, infected wounds, perforated viscera

• Class 1: within 6 hours
• Class 2: within 6-12 hours
• Class 3: >12 hours or gross contamination

• 1. prevent further contamination
• 2. remove foreign contamination
• 3. debridement
• 4. drainage
• 5. promote vascular bed
• 6. closure selection

clean table, cover wound, wear gloves, use aseptic technique, give broad spectrum antibiotics

sterile lube--> shave around wound--> scrub wound--> lavage

rehydrate necrotic tissue, reduce bacterial numbers, remove debris and foreign contaminants

sterile isotonic crystalloids

DILUTED antiseptic

• necrotic tissue is a barrier to cell migration, prolongs inflammation, and delays the repair phase
• debridement minimizes infection and promotes wound healing

• surgical (with scalpel)
• enzymatic
• mechanical (wet to dry bandage)
• interactive dressings
• larval (omg gross)

• use aseptic technique
• obtain deep tissue culture
• remove necrotic tissue
• avoid disrupting subdermal plexus (blood supply to skin)

color, vascularity, warmth, and contractility

• pocket, dead space, when you close a wound
• open wounds do not need drains

• appropriate bandaging techniques to remove exudate, debridement, protect surface of open wound, and stimulates healing and formation of granulation tissue
• topical agents

• First intention: primary wound closure by suturing, delayed primary closure (after you let the wound bed get healthier)
• Second intention: granulation tissue, epithelization and contraction
• Third intention: closure after formation of granulation tissue

depends on etiology, wound size, location, and condition [when in doubt, leave it open and wait to see]

reduce contamination, prevent infection, cleaning/ debriding

• protection
• topical stimulations (moist wound healing)
• epithelialization and contraction (prevent contracture, immobilization of wound area)

protect fragile epidermis (scar is sensitive initially)

• maintain moist environment
• provide local energy source
• reduce edema
• increase level of growth factors
• increase inflammatory response
• improve oxygen content
• improve blood flow

• highly absorptive dressings (hypertonic saline, calcium alginate, gauze)
• moisture retentive dressings (hydrocolloid, hydrogel, polyurethane foam)
• nonadherent semiocclusive dressings (telfa, adaptic)
• select dressing based on how effusive wound is and what type of debridement is needed

• primary bandage layer with considerable absorption
• indicated for partial and full thickness wounds that are very exudative

• primary bandage layers with minimal absorption and donates fluid to wound
• indicated for minimal to moderately draining wounds

• primary bandage layer, in which Na+ from the wound and Ca2+ from alginate interact to form a gel
• indicated for moderately heavy exudative wounds early on

• provide negative pressure to wound to accelerate granulation tissue formation
• fluid/ edema removal improves blood flow, immunomodulation of bad cytokines, bacterial clearance
• provide mechanical stress to cause cells to proliferate

• inflammatory or repair phase only
• exposed bone
• moderate exudation
• large wounds
• reconstructive surgery