55 Basic Wound Management LAB
In this lab we will clip wounds, clean and flush wounds, open glove and gently explore wound, then apply a dressing and bandage. In a later lab we will clip, clean and flush wound, scrub, glove gown, apply 4 quarter drape, debride edges of wound and close wound with sutures.
REVIEW General information below
WATCH clip/cleaning video and bandaging video below
BE READY TO DO in lab and ask questions! Wounds are fun, but do take thought process and planning, you will add to your repertoire with every wound you evaluate!
Background information about wounds to review for this lab:
A good history about what happened is helpful especially if there was a witness to add details about what happened. For example where the animal was bitten, if animal was shaken, or which side of the body was hit by what part of the car and other factors-recall is variable among witnesses!
A thorough physical exam is important in any case of trauma. If bite wounds are involved, a wide clip of the area is important to determine the extent of injury as often jaw pressure on deeper soft tissue takes time to form a bruise and serial exams are very important to monitor wounds over time.
6 steps of Wound management from Dr. Pavletic Angell Memorial Hospital Boston, MA, with tid bits from Dr. Sue Spence, U of MN, CVM.
- Prevent further contamination Povidone iodine 1 part to 9 parts Saline OR Chlorhexidine 1 part to 40 parts sterile saline soaked sterile gauze and cover.
- Debride dead and dying tissue (under sedation/anesthesia) (clip/clean/debride via non-selective methods scalpel or wet-dry bandage sugaring or selective using autolytic-allowing body’s own defenses to work, enzymatic gels/dressings (collaginase common treatment in diabetic ulcers in humans) Medical maggots click for Gladiator video clip
- Remove foreign debris and contaminants (copious flushing-8 psi high volume low pressure so don’t drive debris deeper!) If really contaminated-get the hose first!
- Provide adequate wound drainage (match wound dressing with amount of exudate-sucks up exudate, but still keeps moist environment, keep wound moist)
- Establish viable vascular bed (make sure wound has good blood supply-can be area dependent, head good blood supply, extremities not as great of a blood supply) Need healthy place for granulation bed to form!
- Select appropriate method of closure Primary-right away, Delayed Primary 3-5 days, Secondary 5-10 days , Second-Intention-let the body heal on own
A classic quote regarding in wound care: “its all about Time, Trash, and Trauma.” In other words wounds are evaluated in terms of
Time-age of wound acute/chronic, the longer a wound is neglected the more bacteria will be present
Trash-level of gross contamination or infection of wound
Trauma-to what level of tissues are damaged? joint involved? blood supply in area compromised? underlying unknown damage?
and I would add Topography or where the wound is located on the body and structures involved.
*These evaluations are important as they guide how we treat a given wound and is usually multifactorial. For example: head has good blood supply compared to the extremities and primary closure of older head wound more appropriate than if wound was on distal limb where allowing to heal by second intention is more appropriate. Many of these evaluations and decisions are gained with experience so be sure to ask yourself hmmm why did they choose this method?
4 Basic Wound Classifications (listed in increasing order of severity)
Clean surgical incision made under aseptic conditions NOT when incision involves oral cavity, respiratory tract, GI or genitourinary tract.
Clean-contaminated surgical wounds where the oral cavity, respiratory tract, GI or genitourinary tract are entered without unusual contamination. Wounds with minor contamination or clean wound with minor break in sterility. Usually <6 hrs old.
GOLDEN PERIOD-generally considered about 6 hrs (time it takes for 100 bacteria-100,000/gram of tissue. However time itself not accurate guideline…
- Class 1 < 6 hrs
- Class 2 6-12 hrs
- Class 3 > 12 hrs
Contaminated wounds include open traumatic wounds, wounds made during surgery where a major break in sterility occurs, and wounds made in areas of acute, non-purulent inflammation or made in or near contaminated or inflamed skin.
Dirty and Infected include old traumatic wounds, obvious clinical infection, or perforated viscera. Generally considered >100,000 organisms/gram of tissue (this is not a practical definition other than in research). Risk of infection involves many factors presence of necrotic tissue, poor circulation in area, region of body involved. (
Descriptive terms for wounds
Abrasion: Skin is scraped against a resistant surface (road rash-cycling term)
Avulsions: Displacement/tearing of tissue named for extent of injury
- Complete:displacement or tearing of part of body (complete avulsion of dewclaw)
- Partial:partial detachment of tissue segment (traumatic skin flap)
- Degloving injury: traumatic partial avulsion of skin from the foot circumferentially, (resembles the peeling off of a glove from a hand)
Incision: intended orderly cut with sharp instrument (intentional precise incision)
Laceration: Irregular cut, differing depth, jagged wound (jagged edge cut from object)
Puncture Wound:
- A hole: created by sharp pointed object (not always sharp or fine point!)
- Penetrating wound: puncture enters tissue plane, but does not emerge beyond it
- Perforating wound: puncture enters and exits a given tissue plane or structure (through and through bite wound of scruff of neck)
Contusion: (bruise) An injury in which the skin is not broken however capillaries are ruptured with escape of blood. Healing involves color change as blood is processed purple/red to green/yellow.
Quick review of normal wound healing
Wound healing is a complex and dynamic process involving cytokines that act locally and distantly to orchestrate cells involved in the healing process who, in turn produce various factors. Nutrition status, age, parasite burden and underlying metabolic disease can increase healing time! Sutures often left in longer or remove every other suture in delayed healing cases.
3 Phases overlap given various circumstances
- Inflammatory Phase: (preparatory phase) Immediate-Vasoconstriction, then dilation, start of clot formation, leukocytes, fibrin highway. Lasts about 4-5 days? Signs of inflammation Redness, Heat, Swelling, Pain (Rubor, Calor, Tumor, Dolor) often add disuse (functio laesa)
- Proliferative Phase: Granulation tissue (actually has a pink granular appearance) begins to form migration of cells continues clot acts as matrix, macrophage are important mediators! 1) Neovascularization/angiogenesis 2) Fibroplasia and Collagen formation 3) Epithelialization 4) Wound contracture (experimentally contracture happens at about 0.6-0.75 mm/day, dramatically slows after 6 weeks. Therefore after about 6 weeks, the remaining skin defect will need to close by epithelial cell migration over the defect, or occasionally by surgeon intervention
- Maturation and Remodeling Phase: Collagen remodeling directly related to tensile strength of the wound 3 weeks after injury scar as 20% of final strength. Over the next several weeks scar will achieve only 70-80% of tensile strength of normal skin. Maturation and remodeling day 20 -1 year! Chronic wound beds often lack the vascularity to support further epithelization or acceptance of skin graft-need to prepare the bed.
HOW DO WE HELP WOUNDS HEAL? What are our options?
*If in doubt keep wound open and change and assess daily!
Primary Closure: (healing by first intention-direct closure of recently created wound or clean wound with sutures) closure within 1-2 days
- Wounds with little or no contamination or wounds converted to “clean”
- Skin wounds after complete excision of smaller areas of contamination/infection
- Sufficient adjacent skin available to close the wound without undue tension ALWAYS ALWAYS ALWAYS double check lines of tension and that there is sufficient skin to close before debriding AND have a plan for flap or tension relieving techniques that you can accomplish or refer (don’t get in over your head!)
KEY POINT Almost any wound regardless of how old can be considered for primary closure (surgical closure) IF after Aggressive cleansing, irrigation, and debridement
- All devitalized tissue is removed
- All contaminants and debris are removed
- The tissues appear healthy with viable circulation
- No evidence of infection
However just because you can doesn’t mean you should there are a lot of factors including cost to client, underlying health concerns, and age (old heal slowly, young heal fast)
Delayed primary Closure: wound closure delayed for 3-5 days in order to manage and reassess wound during daily bandage changes. Sterile bandages placed in the wound and changed once to twice a day to allow for proper drainage, resolution of inflammatory phase, and circulation to improve before closure.
- Wounds with borderline contamination despite explore, debride, lavage
- Wounds with moderate tissue trauma or at risk of infection despite explore, debride, lavage
- Wounds with questionable tissue viability-we don’t know if viable or not yet
- Wounds that require serial debridement
- Wounds in which significant tissue swelling prevents primary closure
Secondary Closure within 5-10 days at this point wound has healthy granulation bed (this is a great sign as is natural barrier-don’t need systemic antibiotics anymore, and lets you know necrotic tissue has been eliminated) options include 1) suturing granulation beds together 2) removal of scar and granulation tissue prior to suturing wound (more common in human surgery as can be more cosmetic) 3) removal of some scar and granulation tissue.
- Delayed Primary closure with in 3-5 days not sufficient enough due to persistent inflammation or infection
- Persistence of necrotic tissue that required serial debridement and wound care past 5 days
Second-Intention Healing: (Contraction and Epithelialization) used to close problematic wounds, with proper management (Vetericyn spray) wound contraction and epithelial cell migration over granulation bed is promoted.
- Dirty and infected wounds unable to close by first 3 methods
- Skin defects in areas where there is insufficient loose skin to facilitate primary closure (extremities, tail wounds, large trunk wounds…)
- Financial constraints to closure by first 3 methods
- Puppies and Kittens often heal quite well by second intention
Healing by Adnexal Re-Epithelialization Partial thickness wounds will re-epithelialize via surviving adnexal structures-hair follicles, sweat glands, sebaceous glans in dermis and SQ. However a partial thickness wound can convert to full thickness (deteriorate) without good wound care! (Vetericyn spray). Examples below:
- Abrasions, grazes
- First and second degree burns
- Chemical burns
- Split thickness graft sites
WOUNDS IN A NUTSHELL
- Always do a thorough exam and evaluate healing ability (multifactorial)
- Its all about TIME, TRASH, TRAUMA, and I add TOPOGRAPHY where is the wound
- Sedate/Anesthesia to clip, clean, flush, explore, evaluate, and debride
- Clean, Clean Contaminated, Contaminated, Dirty and infected
- Types of wounds: Abrasion, Avulsion-complete, -partial, degloving, Incision, Laceration, Puncture-hole, penetrating (not all the way through), perforating (all the way through), and Contusion (bruise-healing purple-blue/red-green-yellow)
- Measure, Classify, and Type wound, and give location on body (Body map used as supplement to good a good medical description)
- Methods of debridement (removal of necrotic tissue if infected underneath, or healing has stopped) Selective (less aggressive, slower method-only necrotic tissue is targeted, appropriate if surgical closure not an option) -autolytic gels, dressings, enzymatic gels, medical grade maggots. Selective debridement may be a helpful option if time is not a pressing issue, or if the wound is small (this is what occurs under a non-infected scab). Non-selective surgical (even the best surgeon can’t tell the definite border between healthy and necrotic tissue, so some healthy tissue is removed with necrotic) mechanical wet-dry bandage, sugar bandage. One must plan carefully as may not be room to close by primary or delayed primary closure after debridement!
- Primary Closure-within 1-2 days, ready to close surgically after steps above, Delayed Primary Closure-within 3-5 days needs serial evaluations and wound management for few days before surgical closure. Secondary Closure- within 5-10 days, assisting the body after healthy granulation bed to close wound, serial evaluation, and wound management Second-Intention Healing: Let the body do it with serial wound management. Or for small non-infected wounds (think little kid scabbed knees and elbows)
- Carefully consider your options and discuss with colleagues
- Open wounds need serial assessment and bandage changes
- Wounds need to be kept moist to heal, many specialized dressings on the market
- You will debride and close wounds in the Wound Closure lab later in the semester.
- Click here for wound care supplies
BANDAGING
- Dressing appropriate to level of exudate (deeper/infected generally more exudate)
- Cotton between toes, cotton roll around elbow/tarsus if needed
- Tape stirrups held apart with tongue depressor
- Soft conforming padding distal to proximal, roll off logically around limb, ½ overlap
- Conforming gauze, applied same as above
- Turn tape from tongue depressor onto leg on gauze to hold bandage on
- Vetrap or Elasticon wrapped distal to proximal-leave a bit of each later exposed proximally-strip of conforming padding or cotton, strip of gauze as helps to secure bandage. In general leave toes exposed to check for swelling-exceptions-Florida
- Bandage care handout!
BANDAGING
- Dressing appropriate to level of exudate (deeper/infected generally more exudate)
- Cotton between toes, cotton roll around elbow/tarsus if needed
- Tape stirrups held apart with tongue depressor
- Soft conforming padding distal to proximal, roll off logically around limb, ½ overlap
- Conforming gauze distal to proximal
- Turn tape from tongue depressor onto leg on gauze to hold bandage on
- Vetwrap or Elasticon distal to proximal
- Bandage care handout!
TIDY UP TIME