Second intention healing Flashcards
3 components of second intention healing
- granulation
- contraction
- epithelialization
Rates of contraction in body vs limbs
Body: 1mm/day
Limbs: 0.2mm/day
What can cause delays in contraction?
-inelasticity of skin
-vascular insufficiency
-fewer myofibroblasts
-cytokines
What stops contraction?
- myofibroblasts disappear in larger, older wounds
- contact inhibition
- opposing tension
Rates of epithelialization in body vs limbs
Body: 0.2mm/day
Limbs: 0.09mm/day
What impacts epithelialization?
-dry wound bed (scabs)
-infection
-poor blood supply
-necrotic tissue
-presence of foreign bodies (even suture material)
-systemic factors (cushings or thyroid issues)
Wound management
CRITICAL for healing by second intention
-need debridement, bandaging,
When would you use immobilization techniques for a wound ?
With any wounds in high motion areas
-eg. heel bulb lacerations
Bandage use
- Pressure early!
-minimize swelling
-reduce wound size
-some degree of external coaptation (bring tissues together) - After inflammatory phase
-mechanical protection
-reduce oxygen (increases granulation tissue)
-slow healing
Sarcoid formation
Wounds can result in a sarcoid
-not as common in small animal, but definitely an issue in horses
Managing exuberant granulation tissue
- good wound management initially
- prevention- stop pressure bandages when level with skin and switch to semi-occlusive dressing
Semi occlusive bandage options
-gauzes
-transparent film
-foams
-hydrogels
-hydrocolloids
-hydroconductive dressings
What do you do if you have exuberant granulation tissue?
-surgical debridement (repeatable, will lead to hemostasis so bandage)
-topical medications (owner friendly options, controls granulation tissue)
Issue with using topical medications
Impedes healing
-slows contraction and epithelialization
Corticosteroids
-inhibits granulation tissue
-slow epithelialization
-use judiciously!
-green wound cream, panalog, dexamethazone ointment
White wound lotion
Lead acetate and zinc sulfate product
- not great to use because has metabolic toxins, kills fibroblasts, slows epithelialization, and contributes to lead poisoning
Copper sulfate
-Not great because astringent/caustic, kills fibroblasts
-10% concentration mixed with corn starch
Furacin
Should not be used unless need granulation tissue
-Stimulates granulation tissue production
-inhibits epithelialization
-harbors pseudomonas
Preparation H
- Yeast extract; not great to use
-stimulates granulation tissue, but slows contraction and epithelialization
Amnion
Good choice for Wound dressing
-inhibits granulation tissue, promotes epithelialization and speeds healing
Honey
Mannuka honey or unpasteurized (osmotic)
-can increase exudate
-harmless in wounds and joints
Collagen preparations
-no negatives or benefits but has been used in wounds
Split-thickness skin grafts
-inhibit granulation tissue and promotes wound contraction
-cause use zenographs (pig skin), allografts, autografts
Topical medications
-purple, red, green
-don’t help with healing
-if you won’t put it in your eye than don’t put in wound
Non healing wounds
