wound management 2 Flashcards
Antimicrobial Dressings
- types, how they work and when to apply
- Silver dressings: Mepilex AgTM
> Polyurethane foam (Semi Occlusive)
> Silver is bactericidal - Effective against pseudomonas
- Antifungal
- No known resistance
() - Granulation / epithelialization phase
> Non cytotoxic and increase epithelialization - Bactericidal
- Can be left on wound for 3-7 days
> Grey/Green, odor…normal
Wound Topical Medications
- useful? what types to use?
- Wound Topical Medications
- Does not replace good wound management * Of little benefit but if you decided to use:
- Oil based may be better for healthy granulation tissue because it forms an oily barrier to dehydration
- Water based better for delayed primary closure because it can be lavaged out more easily
Vacuum Assisted Closure (VAC)
- how does it work? what does it do?
- Constant or intermittent vacuum applied to the wound
> Promotes drainage, decreases edema, promotes bacterial clearance
> Increases wound blood flow, promotes granulation tissue and wound contraction - “Open cell” foam covered by airtight plastic, connected to a pump
Open Wound Tx Routine…
- Use correct attire
- Sedation / analgesia (if needed)
- Remove the bandage
- Assess the wound
- Débride (if necrotic tissue present)
- Lavage
- Re-assess the wound
- Re-bandage (usually with honey, sugar or mepilex) until a healthy bed of granulation tissue begins to cover the wound - then non-adherent dressing only
Clean and granulating wound
- what do we do?
- surgical closure (secondary closure)
> complete closure or graft
> partial closure or partial graft
OR - aim for healing by second intention
> continue bandaging
Wound Closure options
- Primary closure
- Delayed primary closure
- Secondary closure
- Healing by second intention
First Intention Healing
- what is this
- Ideal apposition of subcutaneous, dermis and epidermis (your goal if primary closure)
- Epithelial seal within 24h (ideal conditions)
- Fast
- Less scarring
- Less pain
- Less bandaging
Primary Closure (First Intention Healing)
- used for which wounds?
Most surgical wounds which are clean wounds
* Some clean contaminated & traumatic wounds
> Minimal tissue contamination or trauma
()
Primary Closure = Fresh wound
* Caught in a hook, less than 1h ago
* Minimal contamination (clean contaminated)
* Minimal tissue injury
DelayedPrimaryClosure (First Intention Healing)
- what is this for? what does it allow for?
- Wounds that are not closed immediately but are closed before granulation tissue appears (2-5 days)
()
Allows for lavage and debridement of a wound: - Contaminated
- Clean but not fresh when examined
- Contused / swollen
- Tissues that need to declare themselves
Secondary Closure (Third Intention Healing)
- what is this for?
- > 5 days
- Granulation tissue in the wound
- Wounds that are not ready for delayed closure because of excess infection, necrotic tissue or wound already granulated
Secondary Closure advantages
- Limits risks of infection (vs 1st intention)
> More time for debridement
> Granulation tissue acts as a
biological barrier to infection - Limit dead space (vs 1st intention)
- Faster than 2nd intention healing which often lowers cost
Secondary Wound Closure disadvantages
- Closure of a granulated wound can be difficult due to the adherence of the surrounding epithelium to the granulation bed
Second Intention Healing - what does this mean? what do we do?
- Wound is left to heal and close on its own by granulation, epithelialization and contraction
- No actual surgical closure but need wound management, debridement, bandage changes until closed or almost closed
- Can get very labour intensive and expensive!!
Second Intention Healing is ideal for…
- Wounds that are heavily contaminated or bruised
- Wounds that can easily be covered by a bandage
- *Wounds surrounded by enough extra tissues to allow
/ facilitate contraction and closure -
Where primary closure is not possible because there is not enough loose skin
** This is not necessarily cheaper than surgery…
Second Intention Healing - considerations about skin contraction? how to deal with incomplete coverage naturally?
Contraction power is limited… after that you only get epithelial coverage
* This tissue is thin and will be easily traumatized
* Full thickness skin flap or graft is necessary
Second Intention Healing considerations close to joint
Beware of wounds healing by second intention close to a joint … This can result in contracture and decreased range
of motion
options for contaminated, undeclared, need to debride, not enough tissue wounds
Treat Open
- Delayed primary closure (before granulation tissue <5days)
- Secondary Closure (after granulation tissue >5days)
- Heal by second intention contraction and epithelialization
Debridement, lavage and primary closure
- for what wounds?
Convert contaminated wound into one clean enough to be closed primarily (usually over a drain). e.g. bite wounds over the thorax/abdomen
best alternative for many traumatic wounds
Delayed primary closure is the best alternative for many traumatic wounds
* Treat open for 3-5 days and close when cleaner
Heal by second intention or other reconstruction when…
When there isn’t enough tissue to close the wound primarily and this is reasonable
Wound Closure
- how much to resect
At the time of Closure
* Unless fresh wound, sharply resect 1 to 2 mm strip of tissue at the wound edge
minimize what in wound closure
Minimize tension and dead space
()
Gentle manipulation of skin edges
* Towel clamps, skin hooks
* Can reduce tension during closure
* Configuration resulting in the least tension or smallest “dog ears”
how to plan wound closure
- Use sterile technique and towel clamps (the least traumatic tool in your surgery pack for skin) to bring the edges of the skin together in various configurations
- The arrangement that creates the least amount of tension (and often concurrently the smallest dog ears) is the one to pick
- Towel clamps can be left in place as the remainder of the wound is sutured (close dead space sufficiently)
when and how to Undermine Surrounding Skin for wound closure? when not to?
- Release of the elastic skin from the non elastic underlying tissue allowing it to stretch more easily towards the centre of the incision
- Helpful when skin will not appose or apposes under tension
- If the skin edges pull easily into apposition – DO NOT UNDERMINE
() - Combination of blunt and sharp dissection
- Place the scissors (blades closed)
into tissue plane BELOW the panniculus muscle to preserve blood supply to the skin - Open blades, pull back & repeat (don’t cut)
Walking Sutures
- what are they? purpose?
Tack down the dermis to underlying tissue
* Progressively advance from the outer edge toward the center (closing off the wound)
* Decrease dead space
* Distribute tension on wound
Releasing incisions
- how? why?
- Create several small wounds to release tension
- Turn a large wound into a few smaller wounds to help contraction / epithelialization
why we need to eliminate dead space?
Space will fill with fluid and form a seroma
* May resolve on its own / with warm packing if skin is healed
* May result in wound dehiscence
* Increases likelihood of infection
purpose and advantages of penrose drains
- Inexpensive
- Latex
- Passive drainage by capillary action, gravity, and pressure differentials working on the outer surface of the drain
Penrose Drains Application Rules
- Clip liberally
- Use fewest # possible
- Do not exit through primary incision
> Delayed healing - Exit at the most ventral aspect of cavity through separate stab incision
- Do not exit above the pocket
- Do not perforate drain (decreases surface area)
- Do not incorporate in your closure
- Always cover with absorbent bandage
- Remove as early as possible
> Ensure it is removed COMPLETELY
why always cover drains
- To prevent retrograde infection
- To prevent “early” removal by patient
- To evaluate the quantity and quality of fluid produced
- To keep the dog & environment clean
Active Drains
- how do they work? when to use?
Apply negative pressure (suction)
* If anticipate large amount of fluid
* Cannot easily bandage area
* Less likely to become infected
* Does not need to exit in dependent area
* Wound must be completely closed for suction to develop
Drain Removal
- when?
- Remove after 24 hours to 7 days
- Most can be removed in 2-4 days
- Drainage will never completely stop (foreign body)
- When drainage decreases (1-2ml/kg/day) and appears to plateau
- Fluid has changed from purulent to thin serosanguineous
- If abundant / malodorent fluid continues despite drains > Reassess, re-explore and culture…
how to ensure limb bandage not too tight
- Start at the bottom
- Place equal tension (enough but not too much) all
the way up - Watch for:
- Toe swelling
- Coldness
- Pain / discomfort
- Oozing
- Smell
Difficult area to bandage? Try what?
the ‘Tie-over’ bandage
bite wound - force and skin mobility consequence
- Grasped and shaken violently (150-450 psi)
- Inherent mobility of the skin allows extensive movement in the subdermal tissues
> Even with little outward cutaneous trauma
Often can only see the ’Tip of the Iceberg’
are bite wounds contaminated? assocaited with what?
Bite wounds are always contaminated and are associated with more dead space and tissue necrosis
most bite wound damage is where?
- Initial appearance is deceptive
- Most of the damage is under the skin
- Laceration & avulsion of fat and muscle creating dead space under the skin
- Inoculation of underlying (necrotic) tissues
> Oral and skin bacteria
> If untreated, can rapidly become infected - Penetration of chest or abdomen
> Internal organ trauma, rib fracture, intercostal muscle avulsion
Common Bite Wound? how bad?
Thorax 22-35%
* Potentially life threatening
* Severe damage to chest wall, vessels, ribs, lungs
* Pneumothorax, hemothorax
* Lung laceration, contusions
* Flail chest
* Even if no visible skin perforation…
* Smaller dogs predisposed to worse and potentially life-threatening thoracic injuries
Wound contamination, necrotic tissue and dead space will invariably lead to…
will invariably lead to infection even if only a few bacteria are present initially > Sepsis
Sepsis & SIRS
- what is it? from what? how serious?
- Systemic Inflammatory Response Syndrome
- Extensive tissue trauma
- Infection
- Dead space
- Devitalization of tissues & compromised blood supply
- Reported mortality rates are ~7% up to 25%
- Bacteria from oral cavity and cutaneous flora? what does this mean?
- Positive aerobic cultures: 65%
- Positive anaerobic cultures: 15%
- Negative cultures in 33%
()
for bite wounds: - Prompt administration of systemic broad-spectrum
antibiotics
*Ampicillin, clavamox, Ampi + Enro
General Treatment Principles for biite wounds
- Explore wounds to their full extent
> Connect punctures to explore the area where sterile probing reveals dead space
> Explore cavities if they appear to connect
> Identification of occult trauma to deeper tissues - Debride necrotic tissues
- Lavage & culture
- Drain if wound is closed primarily
> Help control / reduce potential infection
When to Intervene Surgically for bite wound
- Penetrating injury to abdominal wall
> Exploratory Laparotomy
> Or at least ultrasound and then decide - All thoracic bite wounds should be explored
> Start with wound exploration and see if thoracotomy is necessary / ensues
Wounds closed in the presence of what…
… are likely to dehisce (breakdown) and result in additional loss of tissue
Wounds closed in the presence of:
* Infection
* Necrotic tissue
* Foreign material
* Excessive tension
* Dead space
If there is any doubt as to whether a wound should be closed …
… Leave it open longer
