Principles of wound management Flashcards
Possible complications of larger wounds - 3
infection
dehisence
seroma formation
compromise of limb function necessitating amputation
What type of wound may heal by secondary intention?
wounds without major tissue loss free of large areas of necrotic tissue confined to non-vital areas open to drainage not overwhelmed by pathogens and contaminants
List the 4 main aims of wound management
achieve a healed wound
minimise scar formation
preserve function
prevent infection
What are the main steps of wound management? 5
initial management assess patient assess wound manage open wound close wound
What can you cover a wound with to prevent further contamination? 3
dry gauze
clean linen
sterile dressing
(rarely is a tourniquet required)
Why might a tourniquet be a disadvantage?
may cause more trauma through ischaemia (especially if applied by lay personnel)
How should the wound be assessed? 6
aetiology location nature extent degree of contamination rest of affected region examined
THORAX: pleural and peritoneal space integrity
LIMBS: underlying bones, joints, neruovascular structures
How often should open wounds be assessed?
every 12-24 hours (serial assessments)
wound progression to be monitored
What is the ‘golden period’ in terms of wound contamination?
< 6 hours after injury, a contaminated wound may be cleaned and closed primarily without development of infection
BUT, factors other than time are more important:
bacterial numbers and virulence
wound factors predisposing to infection
integrity of host IR
AB use - prophylactic or therapeutic
What are the logical steps in promoting the development of healthy granulation tissue? 7
protect wound from dessication and contamination
preparation and clipping
debridmenet
removal of FB and contaminants (lavage)
provision of adequate wound drainage
promotion of a viable vascular bed
selection of appropriate method of closure
When are topical treatments to prevent contamination redundant?
when GT has formed because of its resistance to infection
How can you prevent wound contamination before GT formation?
saline-soaked gauze swabs
water-soluble AB solutions/ointments or antiseptics (0.1% poivdone iodine, 0.05% chlorhexidine diacetate)
animals should be sedated or anaesthetised for this
If conscious - use local/regional anaesthetic techniques (local application, infiltration, ring block, regional block)
How can a wound be protected during clipping?
KY jelly or saline-soaked swabs or temporarily closed (sutures or towel clips)
How should you clip round a wound?
clip from wound margins and move towards the periphery
clip a generous margin round the wound to allow exploration
hair removed with vacuum cleaner
keep blades moist and hair moistened
How is the area around the wound prepared aseptically?
start at wound margin and move to the periphery (keep antiseptic out of wound)
What is the most common cause of delayed wound healing?
inadequate debridement
How can you debride a wound? 3
Which is the most common?
scalpel (sharp debridement, most common) adherent dressing (wet-to-dry, dry-to-dry) hydrogel dressings and enzymes (trypsin and chymotrypsin)
How should a surgeon not debride a wound?
diathermy
ligating large pedicles
excessive retraction or dissection
What should be done with areas of questionable viability?
excised (if not essential to normal function, SC fat) staged debridement (tissue is essential for normal function, tendons)
How should muscle be debrided?
excise (until bleeds/contracts) but preserve function
How is tissue vaibility assessed?
Simple measurements: colour, warmth, pain sensation, bleeding
Complex measurement: doppler ultrasound, transcutaneouus pO2, fluorescein injection, scintigrpahy
May change ofr the better or worse over the first 5 days and staged daily assessment of the wound to let the tissue ‘declare itself’ may be appropriate.
Define ‘layered debridement’
begine at wound margins
progress deeper
thus each layer considered separately
surgeon can be selective in what is removed
Define ‘en bloc’ debridement
complete excision of the wound (as though it was a tumour) with no entry into the wound.
wound may be closed or packed with swabs to facilitate
simple technique
result if a clean wound which may be closed primarily
but a larger wound
damage to surrounding vital structures
How do you deal with gross contamination of tissue that is not redundant?
mechanical removal followed by pressure lavage will remove most contaminants left after the initial debridement
What can you use for wound lavage?
18 guage needle attached to a 20ml syringe and a baf of fluids via a giving set and a 3-way tap
generally performed daily after changing the dressing
What liquid can you use to lavage a wound?
grossly contaminated tissue where high volume needed - tap water via shower head initially
definitive lavage - sterile isotonic fluid (Hartmann’s solution or saline)
Add ABs (ampicillin, cefazolin, neomycin) or antiseptic (chlorhexidine, povidone iodine) sometimes but my be irritating, may inhibit GT formation and may cause sytemic toxicity
What is the best way of keeping a wound drained?
leave wound open
How can you increase wound drainage when you close the wound? 4
leaving part of wound open
fenestration of part of the covering skin surface (meshed free skin grafts)
physiologic implant (omentum)
synthetic implant (surgical drain)
How may the problem that ‘exposed areas of bone dended of periosteum may not support a GT bed’ be overcome?
drill small holes into cancellous bone (forage) to promote the coverage of cortical bone or by using a muscle flap to cover the bone
What are the 2 stages of 2nd intention healing?
contraction and epithelialisation
What are reasons for closing a wound? 6
can convert to a clean wound no skin tension wound is not a crush wound wound is not infected granulating wound wound won't heal by 2nd intention
What are options against closing a wound?
puncture wound
can’t debride and lavage
infected wound
tension on closure
What is primary closure?
When do you use it?
direct apposition on the skin edges
clean or clean-contaminated wounds
What is delayed primary closure?
When?
apposition of the skin edges 2-5 days after wounding during which the wound is covered with a sterile dressing
contaminated wounds
What is secondary closure?
When?
How rapid is wound healing?
wound closure in the presence of granulation tissue
may be combined with reconstructive techniques to avoid excessive wound tension
wounds with superficial contamination or invasive infection - including those wounds closed primarily which subsequently become infected. It is perfomred 5-10 days after wounding and comprises either direct apposition of wounding surfaces (healing by third intention) or excision of GT and primary clsure
wound healing is rapid after closure since the wound is already in the proliferative phase of healing
Disadvantages of secondary closure? 2
reduction in tissue pliability which might make tissue closure difficult
What is second intention healing?
healing by contraction and epithelialisation
useful for dirty wounds in which closure by other 3 techniques not possible
What are the disadvantages of second intention healing? 7
- expensive - if many bandage changes, hospital visits/meds
- healing prolonged
- healing may not complete (chronic non-healing wound may result)
- cosmetic result (hairless epithelium) is relatively poor
- recurrent wound breakdown possible
- stenosis or impairment of function of orifices
- reduction in range of motion of limb
What is another name for a bruise?
contusion
How is wound duration classified?
Class 1: clean lacerations 0 to 6 hours duration, minimal contamination
Class 2: wounds of 6-12 hours duration with significant contamination
Class 3: wounds of 12 hours duration or longer with gross contamination
How should you treat accidental wounds?
Control haemorrhage (pressure not tourniquets) Apply fresh sterile bandage Topical AB (TC or neomycin and bacitracin in 0.9% saline)
What happens if you lavage with balanced electrolyte solution?
efffect is proportional to volume
remove gross debris, fat and blood clots
What happens if you lavage under pressure?
loosens debris
avoid driving contamination deeper into tissue
addition of ABs?
What does hydrogel do?
helps to create/maintain a moist environment of a wound
T/F: muscle that does not bleed or twitch on stimulation should go
True
Name 4 factors you should look for when choosing a dressing
provide support
prevent further trauma
debridement
moist environment
What are passive dressings?
adherent absorbant non-adherent vascular permeable films barrier films
They protect the wound and provide an environment to support healing of the wound.
What do hydrogels do?
Examples? 5
protect the wound and alter or enhance the environment in an attempt to improve wound healing
hydrocolloids hydrogels alginates collagens skin substitutes
What are the advantages of a passive adherent dressing?
excellent debridement - wide meshed gauze allows dessication and tissue adherence
good at combating infection
cheap
Disadvantages - passive adherent dressing?
painful to remove change frequently (24 hours) delay fibroplasia and epithelialisation as wound healing progresses
What do dry-to-dry and wet-to-dry refer to?
adherent dressings
they refer to the condition of the dressing when it is applied to the wound and at the time it is removed.
What are important points to note about wound closure?
may need a combination of techniques
can change your mind
if in doubt, don’t close
What impairs GT formation? 5
necrosis or devitalised tissue in wound infection movement poor blood supply mechanical abrasion
How can you aid GT formation? 5
remove impediments/further debridement
excise old GT bed
enhance blood supply (mm, omentum vascular skin)
reconstruct using tissue with good blood supply
support/immobilise
What can impair epithelialisation? 6
Necrotic or devitalised tissue in wound Infection Eschar Movement Poor blood supply Mechanical abrasion surface trauma
How can epithelialisation be enhanced? 4
- Remove impediments (further debridement)
- Treatment of any infection
- Enhance blood supply (muscle, omentum vascular skin)
- Protection
What can inhibit contraction? 4
- Tension in local skin
- Lack of local skin
- Restrictive fibrosis
- Tight bandages
What can enhance contraction? 2
- Excision of restrictive scar
* Wound reconstruction using skin flap or graft
What should be done with indolent pocket wounds? 6
ID cause control infection excise wound tension free closure/reconstruction manage dead space enhance local vascular supply (omentalisation)
What is an indolent pocket wound?
Which species is most commonly affected?
a pocket/pouch beneath skin margin forms, despite presence of healthy GT bed, result of wound failing to contract and epithelialise
CATS
