Wound Healing and Management Flashcards
What are the 7 stages of wound healing?
Vascular, inflammatory, Re-epithelialisation, Granulation and fibroplasia, wound contraction, neovascularisation, remodelling
Describe stage one, the vascular stage
Vasoconstriction occurs to limit blood loss, vasodilation allows fibrinogen and WBCs to reach wound. Fibronectin forms a mesh in the wounds and platelets clot the blood.
Describe the second stage, ‘inflammatory’
Two WBCS appear: Neutrophils attack debris and bacteria. Macrophages then engulf pathogens and release enzymes which digest blood clots/dead tissue
Describe the third stage, ‘re-epithelialisation’
Epithelial cells begin migrating across fibronectin meshwork. They stop when the cells run into each other this is known as contact inhibition.
Describe the fourth stage, ‘granulation and fibroplasia’
Granulation tissue begins 3/4 days after wound. Contains blood vessels and fibroblasts but NO NERVES. The fibroblasts secrete an enzyme called collagenase which clears away dead tissue.
Describe the fifth stage, ‘wound contraction’
The fibroblasts can develop into myofibroblasts which can contract. Contraction seen 5-15 days later
Describe the sixth stage, ‘neovascularisation’
Formation of a new blood supply occurs. Stimulated by hypoxia at the wounds centre. Once blood supply reaches centre carrying oxygen it leaves an avascular scar. This is called physiological angiogenesis
Describe the seventh stage, ‘Matrix and collagen remodelling’
The type 111 collagen is replaced by type 1 collagen, where it undergoes tissue with greater tension, giving the new tissue strength.
What factors affect wound healing?
Age, physical status, uraemia, malnutrition, drugs
What is debridement?
Removal of dead tissue/foreign objects from a wound
What factors increase the risk of wound breakdown?
Poor care of wound, infection, haematoma, poor surgical/suturing techniques.
With wound care, what are the initial assessments ?
-Stop haemorrhage -Apple sterile non adherent dressing to prevent contamination/achieve haemostasis -Administer pain relief/antibiotics as prescribed by Vet -Cover wound with saline swabs
What does lavaging the wounds consist of?
To flush away microscopic debris and reduce bacteria. Ideal solution is sterile isotonic lactated ringers or 0.9% saline. Lavage should be performed with 1L bag of fluids, 20ml syringe, 18G needle and 3 way tap.
What’s the difference between surgical debridement and non surgical debridement?
Surgical: sharp dissection to remove dead, contaminated tissue while preserving normal tissue
Non Surgical: Wet to dry dressings, useful to remove contamination not removed by lavage.
What is primary closure?
An appositional healing that is used in clean, fresh wounds under no tension. Suitable for new wounds (6-8hours old) which have minimal contamination/was lavaged.
