Wound Healing Flashcards
What are 3 ways to stop a wound from bleeding?
- Pressure bandage
- Clamp
- Ligate
What are the first three things to consider with wound management?
- Stabilize
- Preserve life
- Evaluate the wound
If an animal has been previously vaccinated, what type of tetanus prophylaxis should be used?
Tetanus toxoid
If an animal has not been previously vaccinated, what type of tetanus prophylaxis should be used?
- Tetanus toxoid
- Tetanus antitoxin
Which type of bacteria is most commonly isolated from horses?
Streptococcus
Which 2 types of bacteria are most commonly isolated from ruminants?
- E. coli
- Arcanobacterium/Trueperella pyogenes
What are 3 examples of systemic antibiotics that can be used?
- Penicillin
- Penicillin/Aminoglycoside
- TMS
If local antibiotics are used, they might inhibit what?
Wound healing
Phenylbutazone (Bute) is only used in what large animal species?
Horses
What NSAID can be used in cattle?
Flunixin meglumine (Banamine)
What are 3 reasons to give NSAIDs with wound healing in large animals?
- Block prostaglandin synthesis
- Decrease inflammation
- Decrease pain
What are 4 classifications of wounds?
- Clean
- Clean/contaminated
- Contaminated
- Infected
A wound made sterilely under surgery is classified as what?
Clean
If pus is present in a wound, the wound is considered what?
Infected
The period of time after a wound has occurred during which the wound may be closed primarily is known as what?
Golden Period
When is the golden period for wound healing?
4 - 6 hours
If past the golden period, should the wound be sutured?
No
What are 4 classifications of wound healing?
- Primary intention
- Delayed primary
- Second intention
- Tertiary intention
Healing without fibroplasia is what type of wound healing?
Primary intention
Primary intention healing can be done with what type of wound?
Clean wound
What are 2 types of suture patterns that can be used to close the skin in large animals with primary wound healing?
- Simple interrupted
- Vertical mattress
What is a suture pattern that is good for use on the line alba in the horse?
Near-far-far-near
If a wound occurred more than 6 hours ago, how is it classified?
Contaminated
If a wound has a large gap and necrotic looking muscles, should the wound be closed?
No
What are 3 aspects of cleaning a wound?
- Pack
- Clip
- Lavage
What should be done before clipping a wound?
The wound should be packed.
What should be used to lavage a wound?
What can be used in the field?
- Fluid that is physiologic
- Water
When does the body of the animal begin debridement?
6 hours after wound occurs
What are 2 types of cells involved in debridement?
- Neutrophils/PMNs
- Monocytes
Delayed closure of a contaminated wound is known as what type of healing?
Delayed primary intention
Contaminated wounds are left open until what occurs?
Until the infection is under control.
Wounds should be closed before when?
How long does this take?
- Before period of fibroplasia occurs
- Less than 4 days
What are 3 steps involved in second intention healing?
- Fibroplasia
- Contraction
- Epithelialization
What is the goal of second intention wound healing?
To provide an optimal environment for wound healing.
What are 2 examples of stimulants for granulation tissue formation?
- Hydrotherapy
- Moist & irritant dressings
What are 4 effects of cold hydrotherapy on a wound?
- Vasoconstriction
- Decreased metabolism
- Cutaneous anesthesia
- Cell death
What are 3 effects of heat hydrotherapy on a wound?
- Vasodilation
- Increased metabolism
- Decrease pain
What are 4 examples of inhibitors of granulation tissue?
- Pressure
- Dry dressing
- Corticosteroid cream
- Caustic agents
What are 2 ways to create pressure in order to inhibit granulation tissue?
- Bandage
- Cast
When is the period of fibroplasia for wound healing?
Days 4 to 16
What takes place during the period of fibroplasia of wound healing?
Rapid collagen synthesis
What is the lag period for wound contraction (when does it begin)?
9 days
Complete closure of a wound is determined by what?
Amount of skin available.
What can wound contraction be inhibited by?
Exudate
What takes place under a scar?
Centripetal migration
What are 3 different components of epithelialization?
- Mobilization
- Migration
- Mitosis
After wound contraction ceases, closure is completed by what?
Epithelialization only
With large animals, exuberant granulation tissue can form where?
Distal limbs
Why does exuberant granulation tissue tend to form in distal limbs of large animals?
Slow healing time
Epithelialization of a truncal wound occurs at what rate?
Of a distal limb wound?
- 0.2 mm/day
- 0.09 mm/day
Wound contraction of a truncal wound occurs at what rate?
Of a distal limb wound?
- 1 mm/day
- 0.2 mm/day
What are 2 problems with exuberant granulation tissue?
- Cosmetically displeasing
- Can impair function
What is another name for exuberant granulation tissue?
Proud flesh
What is a differential for proud flesh?
Sarcoid tumor
What is one way to decrease bleeding of a leg wound?
Hanging limb upside down and using a tourniquet.
Which 2 species are the only mammals to develop excessive granulation tissue during wound healing?
- Humans
- Horses
Abnormal collagen production and organization can produce what?
Exuberant granulation tissue
What can exuberant granulation tissue delay?
Wound healing
Growth of exuberant granulation tissue is promoted by what type of treatments?
Ones that arrest wound contraction and epithelialization.
What is a common treatment option for exuberant granulation tissue?
Surgical resection
What is the number one reason for the use of skin grafting in large animals?
Exuberant granulation tissue
How often should a pressure bandage be changed?
Every couple of days.
What are heel bulb lacerations usually caused by?
Contact with wire or other metal objects.
Why is a thorough examination of heel bulb lacerations warranted?
Adjacent synovial structures may be affected.
With heel bulb lacerations it is important to check what?
Wound depth
With heel bulb lacerations it is important to check if what is involved?
Joint
Involvement of what joint in a heel bulb laceration is associated with a poor prognosis?
Distal interphalangeal joint
What is the difference between delayed primary healing and third intention healing?
No granulation tissue formed in delayed primary healing.
What is something that can be used to reduce movement to allow for wound healing?
Cast
Skin grafting is done on what type of surface?
Clean bed of granulation tissue or a clean wound.
What type of skin graft is between species?
Xenografts
What type of skin graft is between two different animals of the same species?
Allograft
What is the purpose of skin grafting?
To provide dermal coverage of a wound and to stimulate epithelial edges of a wound.
Which type of skin graft involves a portion of the dermis?
Which type involves the epidermis plus the dermis?
- Split thickness
- Full thickness
Which type of skin graft gives the fest cosmetic appearance and hair growth?
Full thickness
What is a disadvantage of skin grafting?
Limited amount of donor skin available.
Are free grafts used more in small animal or large animal surgery?
Large animal
What are 2 types of free grafts?
- Island/seed (pinch or punch)
- Sheet (split or full)
What are 3 advantages of a pinch/punch graft?
- Harvested and placed without general anesthesia
- Equipment and technical requirements are minimal
- Complete graft failure is rare
What is a disadvantage of a pinch/punch graft?
Poor cosmetic result with scant hair growth
Use local anesthesia, form a skin tent with forceps, cut at a right angle and remove a 3mm disk of tissue is the harvesting process what type of graft?
Pinch graft
Insert graft into pocket, beginning distally, usually using a dull needle to push into the pockets is the process for placing what type of graft?
Pinch graft
What should be placed over a pinch skin graft?
Bandage
When should a pinch graft be checked?
After 5 days
What is used to harvest a graft punch?
6 mm biopsy punch
What is a punch graft placed on while waiting to insert it?
Blood soaked sponge
What are 3 good donor sites for pinch/punch grafts?
- Neck
- Ventral abdomen
- Pectoral region
What is placed to close the harvest site of a punch graft?
Simple interrupted suture
What size hole is punched into the recipient site?
4 mm
What type of graft is inexpensive and easy to do?
Punch graft
What is the percentage range of times that punch grafts will take?
60-95%
Where is a common location for punch grafts to be used?
Distal limb
Split thickness and full thickness grafts are examples of what type of grafts?
Sheet grafts
What type of sheet graft technique increases the number of edges for epithelialization?
Mesh technique
What is a good type of graft for covering awkward surfaces?
Mesh graft
Are mesh grafts easy or difficult to immobilize?
Easy to immobilize
Mesh grafts produce problems from what?
From serum/blood
What tool can be used to harvest a skin graft?
Dermatome
What is a benefit of using a mesh graft?
Excellent drainage
What are three was skin grafts are secured to the bed?
- Suture material
- Staples
- Glue
How long is the graft very fragile for?
The first week
When is the first bandage change done?
Day 5
How long do skin grafts take to heal?
A LONG TIME!
