Wound healing Flashcards
Term: Closed wound
Contusion or crushing injury
Term: Open wound
Abrasions + Avulsions + Incisions + Lacerations
Term: Clean wound
Surgically created under aseptic conditions
Term: Clean-contaminated
Surgical wound into respiratory + alimentary + urogenital tract
Term: Contaminated
Open, acute, accidental or surgical wounds with a major break in sterility
Term: Crush wound
Result of body part being subject to high degree of force
Term: Contusion
A blod to the skin which blood vessels are damaged and rupture
Term: Abrasion
Damage to the epidermis and portions of the dermis by blunt trauma or shearing forces
Term: Avulsion
Loss of skin by tearing of tissue from attachments
Term: Incision
Sharp object that has minimal adjacent tissue damage
Term: Laceration
Irregular wound created by tearing of the tissue
Term: Puncture
Penetrative injury with minimal skin damage + variable underlying tissue damage
What are the four stages of wound healing?
Inflammatory
Debridement
Repair
Maturation
What kind of response is the inflammatory phase of healing?
Protective tissue response
What four big things occur during the inflammatory phase of healing?
Vascular constriction for 5 to 10 min
Vascular dilation
Extrinsic pathway activation by thomboplastin
Platelet aggregation + clot formation
What is the inflammatory phase causes vasoconstriction?
Catcholamine
Serotonin
Bradykinin
Histamine
What is occurring with in the inflammatory tissue in that inflammatory phase?
Localized when fibrin + plasma exudate plug the lymphatics
Clot dries –> scab forms
How long is the inflammatory phase?
3 to 5 days
What is the debridement phase characterized by?
Exudate
What is in the exudate in the debridement phase?
WBC’s + Necrotic tissue + Wound fluid
At what point do neutrophils show up to the injury?
6 hours post insult
At what point do monocytes show up to the injury?
12 hours post insult
What cell type is essential for wound healing?
Monocytes
How long does it take monocytes to become macrophages at the injury site?
24 to 48 hours
What four functions do macrophages provide at the injury site once they are activate?
Secrete collagenases + GF
Recruit mesenchymal cells
Stimulate angiogenesis
Modulate matrix production
At what point post-injury does the repair phase occur?
3 to 5 days
What occurs during the repair phase?
Fibroblasts migrate to the wound
Followed by angiogenesis
Type 3 collagen is deposited
What time point post injury is the max amount of collagen present?
2 to 3 weeks
What happens to the type 3 collagen in the wound
converts to type 1
What structurally makes up granulation tissue?
Capillaries + FIbroblasts + Fibrous tissue
What occurs at the maturation phase?
Wound strength is at its maximum
What % of original tissue strength is regained?
80%
What happens in the maturation phase?
Granulation tissue loses some of its cellularity
When is the most rapid increase in the strength of the wound during healing?
During days 7 to 14
What is moist wound healing?
Occlusive bandage to facillitate healing
Low oxygen tension within wound
Increase local temperature to site of wound
What are the advantages to moist wound healing
Optimal environment for healing Hastens debridement + granulation formation Limits infection Less scars and no scabs Less painful
How much does epithelialization increase by with moist wound healing?
twice as fast
What is the disadvantage of moist wound healing?
Bacterial COLONIZATION of wound surface + foliculitis + maceration of wound border
What Four big things affect wound healing?
Age + Serum protein level + Disease + Obestit
What level of serum protein do we start to see healing issues?
Below 1.5 to 2 g/dl
What diseases cause a decrease in a patients ability to heal?
Hepatic disease
Hyperadrenocorticism
Diabetes mellitus
What is different about the way cats heal?
Cutaneous wounds close slower
Slower by second intention
Produce less granulation tissue
Heal more by contraction of wound edges
What are some underlying tissue types that DO NOT support granulation tissue?
Periosetum + Tendon + Nerve sheath
What are common external factors applied to patient to help/harm with wound healing?
Radiation therapy
Corticosteroids
Chemotherapy
Hyperbaric oxygen therapy
What does radiation therapy do to wound healing?
Inhibits all stages of wound healing by affecting angiogenesis
What does corticosteroids do to wound healing?
Depress all stages of wound healing and increase change of infection
What are the fundamentals of wound management
Stabilize patient Cover wound till you can address it Clip and clean area Debride dead or necrotic tissue Lavage wound Perform appropriate wound closure
What are the tips for a good surgical debridement?
Start superfically and progress deeper
Sharp dissection techniques
Debribe muscle till it bleeds
Remove any and all contaminated fat
What is autolytic debridement?
Creation of moist wound environment to facilliate increase endogenous enzymes
Which is more prefered surgical or autolytic debridement?
Autoylytic
Which is faster surgical or autolytic debridement?
Surgical
What do you use on a wet bandage?
Hypertonic saline
What is bandage debridement?
Place ment of dressings that are allowed to dry on the wound
When is bandage debridement most effective?
Early stages of wound healing
– or –
Infected wounds
What is the down side to bandage debridement?
Very painful, can damage surrounding healthy tissue
What is the advantage of enzymatic debridement?
Poor anesthetic canadiates
What are the disadvantages of enzymatic debridement?
Must reamin contact for adequate time to acheive result
Local tissue irritation
What is biosurgical debridement?
Maggot therapy
When is primary wound closure appropriate?
Clean or clean contaminated wounds that have been converted to clean wounds
When is primary wound closure recommended?
Wounds that require immediate closure
What is an important consideration when it comes to primary closure?
Close without a lot of tension
When does delayed primary closure occur?
2 to 5 days post injury
When is delayed primary closure appropriate?
Clean contaminated + Contaminated wounds with questionable health (Edema + skin tension)
What is an important consideration of delayed primary closure?
Debride tissue and lavage wound before closure
When is secondary intention healing appropriate?
Wounds unsuitable for closure
Large skin defects or extensive tissue devitalization
How does healing occur with secondary intention healing?
Via granulation tissue + wound contraction + epithelialization
