Lecture 11 - Basic Wound Care and Skin Grafting Flashcards
What does DIMES stand for?
debride, infection, moisture, edge protection, and support
What are the types of debridement?
surgical, autolytic, enzymatic, mechanical, and biosurgical
What is surgical debridement?
when devitalized tissues are removed with sharp dissection
What is removed during surgical debridement?
fat, fascia, skin, and muscle
In surgical debridement you want a ______ edge.
bleeding
What is surgical debridement often combined with?
autolytic debridement
What is osteostixis/forage?
the use of small pins to penetrate bone that is exposed
What does osteostixis/forage promote?
vascular medullary canal communication with the wound bed
Osteostixis/forage enhances _____.
healing
When is autolytic debridement preferred?
with tissue viability
What type of dressings do you use with autolytic debridement?
hydrophilic, occlusive dressings
What is enzymatic debridement?
enzyme agents are applied topically to dissolve collagenous tissue and cause superficial sloughing of debris
What is enzymatic debridement an adjunct to?
lavage and surgical debridement
What enzymes are used for enzymatic debridement?
trypsin, collagenase, papain, and urea
What is enzymatic debridement used for?
chronic, nonhealing, indolent wounds
If wet-to-dry dressings are done, how long are they usually done for?
1-2 days
Wet-to-dry dressings and enzymatic debridement are both ________ debridement.
nonselective
What are the risks that accompany wet-to-dry dressings?
they can leave lint/fiber in the wound and they inhibit epithelialization
What are some forms of biosurgical debridement?
maggots and leeches
If you use a maggot for biosurgical debridement, how many do you put per cm squared of wound surface area?
5-10 larva
What do you cover the maggots with in biosurgical debridement?
dacron chiffon dressing
What do maggots do in biosurgical debridement?
they secrete enzymes that dissolve necrotic tissue
What can be the negatives to using maggots for biosurgical debridement?
they can destroy healthy epithelium if not careful or be irritating to the patient
What do leeches do in biosurgical debridement?
they can improve skin perfusion
What are leeches used for in biosurgical debridement?
venous insufficiency and to salvage skin flaps and grafts
What is the goal of moist wound healing?
to keep the wound exudate on the wound bed
What type of debridement does moist wound healing allow for?
autolytic debridement
What does moist wound healing promote?
granulation tissue formation and epithelialization
What does moist wound healing prevent?
desiccation and tissue devitalization
What does moist wound healing limit?
infection
What are some things used for inflammation/debridement?
hypertonic saline and TenderWet
What are some things used for inflammation/early repair?
sugar, honey, alginate, hydrogel, hydrocolloid, and foam
What does hypertonic saline do?
its osmotic gradient lyses and destroys bacteria
What does hypertonic saline reduce?
edema
What does hypertonic saline remove?
exudate and debris
When is hypertonic saline used?
in heavily exudative, necrotic, and infected wounds
What can happen if hypertonic saline is left on for too long?
it can dehydrate viable tissue
What is TenderWet?
hypertonic Ringer’s solution
Is sugar hypertonic or hypotonic?
hypertonic
What does sugar do in wounds?
dehydrates bacteria to inhibit growth
What does sugar enhance?
granulation formation and epithelialization
How do you apply sugar on wounds?
1cm thick on the wound surface with an absorbent bandage
What can sugar be combined with for an antimicrobial effect?
betadine solution
When is sugar used and in what type of wounds is it used in?
in the inflammatory phase in exudative wounds
What does honey do in wounds?
its hyperosmolarity decreases edema and inflammation, and enhances debridement
What does honey promote?
granulation and epithelialization
What does honey have that makes it antimicrobial?
it releases a small amount of hydrogen peroxide and methylglyoxal
What is honey used for?
inflammatory and early repair
What are some types of honey that is used in wound healing?
manuka honey and medihoney
What is alginate?
polysaccharide fibers that are in sheets or rope
What type of agent is alginate?
a hemostatic agent
What does alginate form?
hydrophilic gel-like substance on the wound
What does alginate maintain?
moisture - it absorbes 20-30x its weight
What can alginate supply?
calcium, zinc, manganese, and silver
When is alginate used?
for early inflammation, heavy exudate wounds, deep wounds, and after surgical debridement
When can alginate dehydrate a wound?
if there is not enough exudate
What is polyurethane foam?
an absorbaent, nonirritating synthetic polymer
What does polyurethane foam maintain?
moisture with wound surface
What can polyurethane foam slow?
granulation tissue formation
What does polyurethane foam promote?
epithelialization
What does polyurethane foam provide?
thermal insulation
What is a negative of using polyurethane foam?
it can dessicate tissues if they are non-exudative
What is polyurethane foam used for?
repair phase mostly, moderate exudative wounds depending on the product
What is hydrocolloid?
sheet, paste, or powder that turns into gel with absorption
What does hydrocolloid promote?
autolytic debridement, granulation tissue formation, and epithelialization
What can hydrocolloid inhibit?
wound contraction and promote excess granulation tissue
When do you want to avoid using hydrocolloid?
in infected wounds
What is hydrocolloid used for?
inflammatory or repair phase with low-to-moderate exudate
What is hydrogel?
gel, impregnated guaze or sheets up to 95% water
What type of dressing is hydrogel?
hydrophilic
What can happen if hydrogel is not cut to the size of a wound?
it can macerate the wound edges
What is hydrogel used for?
inflammatory and early repair with minimally exudative wounds to promote autolytic debridement and over granulation tissue to promote epithelialization and contraction
What are some antimicrobial dressings?
triple antibiotic ointment, silver, tris hydroxynethyl aminomethane buffer, and hyperosmotic dressings
What are some examples of triple antibiotic ointment?
bacitracin, neomycin, and polymyxin
Triple antibiotic ointment is more effective at ______.
prevention
How is silver used as an antimicrobial dressing?
silver sulfadiazine cream, nanoparticle or impregnated-dressings
What is silver effective against?
broad-spectrum antibacterial and antifungal
What does silver enhance?
epithelialization
What is tris hydroxymethyl aminomethane buffer good for?
pseudmonas
Tris hydroxymethyl aminomethane buffur has antimicrobial properties of ______.
EDTA
What is the purpose of nonadherent dressings?
to prevent adhesion of the bandage
What do nonadherent dressings allow for?
exudate transfer to overlying bandage
What are nonadherent dressings used for?
the repair phase, over grafts or sutured wounds
What are some examples of nonadherent dressings?
petroleum-gauze and tefla pads
Semiocclusive dressings are _______ so they don’t ______ exudate.
waterproof; absorb
What is a negative to using semiocclusive dressings?
they may trapwound fluid and promote bacterial growth
What are semiocclusive dressings used for?
partial thickness wounds or suture wounds
What are some examples of semiocclusive dressings?
Opsite, Tegaderm, bioguard, and primapore
What is negative pressure wound therapy?
vacuum assisted closure that uses subatmospheric pressure across the wound
What does negative pressure wound therapy do to the wound?
improved wound perfusion, decreased edema, decreased bacterial colonizaiton
What does negative pressure wound therapy stimulate?
granulation tissue - removes wound exudate
What does negative pressure wound therapy expedite?
contraction and epithelialization
When is negative pressure wound therapy used?
in deep wounds, chronic wounds, infected wounds, and adjunct to skin flap or graft
How often is negative pressure wound therapy changed?
every 3-5 days
What must be considered for wound closure?
- size and shape of the wound
- anatomic location
- chronicity
- wound bed condition
- state of the periwound skin
- animal health and stability
- the owner
- surgeon ability and expertise
What are the goals for reconstruction?
- minimize tension and motion
- return function to the area
- to ensure final outcome is free of ongoing morbidity
What are the options for wound closure?
direct apposition, tension-relieving techniques, skin flap development, free skin grafts, second intention wound healing, and combination
What are some examples of skin grafts?
random pattern flap, axial pattern flap, free skin graft, microvascular free graft, and composite graft
What vessels does the random pattern flab use?
subdermal plexus
What vessels does the axial pattern flap use?
direct cutaneous artery
How are subdermal plexus flaps made/executed?
epidermis and dermis is detached from the surrounding skin, stretched and rotated
What are subdermal plexus flaps limited by?
skin tension, mobility, and elasticity
How is an advancement flap used/executed?
adjacent, loose, elastic skin used to slide into the defect
What are some examples of advancement flaps?
H-plasty and scrotal flap
How is the rotational flap used/executed?
it is developed and pivoted over a defect with a common border; can be bilateral
When is a rotational flap used?
to close circular or triangular defects
How is a transitional flap used/executed?
rectangular local pedicle brings additional skin, developed 90 degrees of long axis of defect
How is the size of a transitional flap determined?
it should be the same width as the defect, the length is equal to defect from the pivot point
What are some examples of transitional flaps?
Z-plasty, elbow fold flap, and flank fold flap
How is an interpolation flap used/executed?
rectangular pedicle is rotated into nearby vs. adjacent defect
What is an interpolation flap modified from?
a transposition flap without a common border
In the interpolation flap, the length must include the _____ ___ ______.
inverting skin segment
What is an example of an interpolation flap?
lip-to-lid flap
What skin is used for a distant flap?
skin that is not adjacent to the wound
What is required for a distant flap?
a staged procedure
What are some examples of a distant flap?
pouch, tube flaps
What are axial pattern flaps based upon?
specific direct cutaneous artery and veins
Axial pattern flaps can be rotated up to _____ degrees.
180
When are axial pattern flaps usually used?
to bridge an incision with primary closure of the donor bed
When are axial pattern flaps more likely to fail?
if it exceeds the length recommendation
What is considered the most difficult flap?
the omocervical flap
What vessels are involved in the omocervical flap?
cervical cutaneous branch, omocervical artery and vein
Where is the omocervical flap used?
in the head, neck, face, ear, palate, cervical, shoulder, and axillary defects
What vessels are involved with the thoracodorsal flap?
cutaneous branch, thoracodorsal artery and vein
Where are thoracodorsal flaps used?
thoracic, shoulder, forelimb, and axillary defects
What vessels are involved with the dorsal deep circumflex iliac flap?
deep circumflex iliac artery and vein and dorsal branch
Where are dorsal deep circumflex iliac flaps used?
ipsilateral flank, lateral lumbar, pelvic, area over greater trochanter, lateromedial thigh defect
What is the easiest and most consistent flap?
the caudal superficial epigastric flap
What vessels are associated with the caudal superficial epigastric flap?
external pudendal artery and vein
Where are caudal superficial epigastric flaps used?
in the caudal abdomen, flank, inguinal, preputial, perineal, thigh, and stifle defects
What vessels are associated with cranial superficial epigastric flaps?
short cutaneous branch, cranial superficial epigastric artery and vein
When are cranial superficial epigastric flaps used?
sternal defects
What vessels are associated with reverse saphenous conduit flaps?
saphenous arteries and medial saphenous veins
Where are reverse saphenous conduit flaps used?
distal limb and tarsal region
What vessels are associated with the caudal auricular flap?
sternocleidomastoideus branch, caudal auricular artery and vein
Where are caudal auricular flaps used?
neck, face, dorsal head, and ear reconstruction
What are lateral caudal flaps associated with?
tail amputation
What vessels are associated with lateral caudal flaps?
right and left lateral caudal artery and vein, and branches of caudal gluteal artery and vein
Where are lateral caudal flaps used?
perineal and caudodorsal pelvic defects
What vessels are associated with the superficial temporal flap?
superficial temporal artery
Where are superficial temporal flaps used?
maxillofacial, medial eyelid, and palate defect
What vessels are associated with the angularis oris flap?
angularis oris artery and vein
Where are angularis oris flaps used?
palate, face, and nasal reconstruction
What do composite flaps incorporate?
underlying structures with overlying skin
What are some examples of composite flaps?
myocutaneous flap (latissimus dorsi flap) and mucocutaneous flap (lip-to-lid and labial advancement flap)
What are free skin grafts classified by?
thickness, donor, mesh vs. non-meshed, and type
What are the thickness types of free skin grafts?
full and partial thickness
what are the donor types of free skin grafts?
autograft, allograft, and xenografts
What are the different types of free skin grafts?
sheet graft and island grafts
The thinner the graft the _____ success for ______.
greater; success
The thicker the graft the ____ the ______ _____.
better; cosmetic result
What parts of the skin are used in ‘full thickness’ skin grafts?
epidermis and entire dermis
What parts of the skin are used in ‘partial thickness’ skin grafts?
epidermis and portion of dermis
Recipient beds are NOT what?
irregular surfaces, directly over bone, tendon, and ligament, irradiated tissues, avascular tissues, or infected or hypertrophic granulation tissue
Recipient beds ARE what?
acute wounds and healthy bed of granulation tissue
When harvesting skin what must you keep in mind?
that the skin is similar thickness and the hair contour, color, and growth pattern is the same
How do you get the moroccan leather appearace when harvesting donor skin?
remove all SQ fat
What does engraftment mean?
to take
What are the steps of engraftment?
adherence, plasmatic imbibition, inosculation, revascularization, and reinnervation
What occurs in phase I of adherence?
adhesion between fibrin strands on exposed graft surface to recipient bed
What occurs in phase II of adherence?
conversion to fibrous adhesion
How long does it take for phase II of adherence to occur?
begins at 72 hours and is completed by 10 days
What occurs during plasmatic imbibition?
graft vessels dilate and pull in cells and fluid via capillary action
What is inosculation?
anastamosis of graft vessels with recipient vellses
When does inosculation begin?
at 48-72 hours
When does normal flow in inosculation return?
by 5-6 days
What is the scaffolding for inosculation made out of?
fibrin network
How long does it take for lymphatic drainage to return in skin grafts?
4-5 days
How long does it take for reinnervation to return in skin drafts?
3-4 weeks
Through the engraftment process what does the graft look like at 2 days, 2-4 days, 3-5 days, and 7-8 days?
first 2 days - pale
days 2-4 - purpule
days 3-5 - lighter red
days 7-8 - red to pink if surviving
If a skin graft is white to tan what does that indicate?
avascular necrosis
If a skin graft is black what does that indicate?
dry ischemic necrosis
What are major causes for failure of engraftment?
motion, lifting from the recipient bed (due to hematoma, seroma, or exudate), or infection
