Lecture 8, wounds and wound management Flashcards
1
Q
Wound etiology
A
- Identification of the causative agent necessary before initiating treatment
- Trauma vs. dermatologic disease (including parasitosis) vs. neoplasia vs. ?
- Important to treat the underlying cause in case of non-traumatic wounds
- Some wounds are impossible to treat successfully
2
Q
Wound irrigation (lavage)
A
- Dirty or contaminated wounds can be cleaned by irrigation
- Obvious debris, necrotic tissue, dirt and bacteria will be washed away by fluid under pressure
- Irrigation pressure should not be too high because it may damage
tissue and push contamination further into the wound - Minimal to moderately contaminated wounds – cleaning performed using isotonic saline or Ri-Lac
- In selected patients, dilute antiseptic solutions such as 0.05%
chlorhexidine or 1% povidone–iodine solution can be used
3
Q
Debridement
A
- In case of debris or necrotic tissue
- Anaesthesia often required
- Objective to convert the open contaminated wound into a surgically clean wound
- Different methods (choice depends on the patient): surgical,
mechanical, autolytic, enzymatic, chemical, biosurgical - More than one procedure may be necessary
4
Q
Surgical debridement
A
- Used most commonly
- Goal is to remove all obvious necrotic tissue and debris
- Difficult to distinguish necrotic nonviable tissue from healthy viable
tissue during the inflammatory phase - Layered approach often used (superficial tissues removed first)
- Removal to the level where active bleeding is present
- Questionably viable tissue should be left in place and re-evaluated
- En-bloc debridement sometimes used (complete excision of the
wound and all affected tissue)
5
Q
Mechanical debridement
A
- Performed using wet-to-dry or dry-to-dry dressings after layered surgical debridement or as the sole means of debridement
- Wet-to-dry dressing (typically changed daily until granulation)
- Primary dressing of gauzes wetted with isotonic saline
- Several layers of wet gauze followed by several layers of dry gauze added
- As the bandage dries, it adheres to the wound surface
- Adhering tissue is removed as the dressing is changed
- Dry-to-dry – same procedure without wetting
- Several disadvantages
- Some authors believe that these dressings no longer meet the expected standard of care in veterinary medicine
6
Q
Autolytic debridement
A
- Creation of a moist wound environment to allow endogenous
enzymes to dissolve nonviable tissue - Often preferred in wounds with questionable tissue viability
- Highly selective for devitalized tissue
- Can be performed with interactive dressings such as hydrogels,
hydrocolloids, hydrofibres and foam dressings - Use of honey or sugar topically (attraction of fluid)
- Painless
- Slow process
7
Q
Enzymatic debridement
A
- Proteolytic enzymes are applied to the wound to break down the
necrotic tissue - Wounds with small amounts of necrotic tissue or debris
- (Trypsin, fibrinolysin, chymotrypsin, desoxyribonuclease, papain-urea and collagenase)
- Sometimes used as an adjunct to mechanical and chemical wound
debridement - Effectiveness questionable
- Slow process
8
Q
Chemical debridement
A
- Nonselective method (cells important for healing are also damaged)
- Can be performed with antiseptics
- (Dakin’s solution, chlorhexidine, povidone-iodine, hydrogen peroxide)
- Not generally recommended
9
Q
Biosurgical debridement
A
- Placement of medical maggots (Lucilia sericata) into the wound
- The maggots produce enzymes that dissolve the necrotic tissue, but
spare healthy tissue - Maggots specially bred, expensive
- May be indicated for management of deep wounds
10
Q
Topical antibiotics and antiseptics
A
- Systemic AB preferred (only for infected wounds)
- The use of topical antibiotics and antiseptics is controversial – no
beneficial effect once infection is established - Do not replace proper debridement
11
Q
Topical wound medications
A
Antimicrobials and antibiotics:
* Triple antibiotic ointment
* Silver sulfadiazine
* Nitrofurazone
* Gentamicin sulfate
* Cefazolin
* Mafenide
Wound-healing enhancers:
* Aloe vera
* Tripeptide-copper complex
* D-glucose polysaccharide
* Honey
* Sugar
* Growth factors
* Hydrolyzed bovine collagen
* Chitosan
12
Q
Open wound management
A
- Due to wound characteristics/financial reasons/until surgical closure
- Superficial wounds
- Dressing, bandage?
- Wound-healing enchancers used
- Healing process often time-consuming
- Might need some surgical intervention
13
Q
Wound closure
A
- Decision whether or not to close the wound, when?
- Primary closure
- Delayed primary closure
- Secondary closure
- Drainage
- Tension lines (incisions/closure
parallel to tension lines if possible)
14
Q
Primary closure
A
- Preferred for clean wounds, including surgical wounds and
contaminated wounds that have been debrided and are less than 6
hours old - Direct closure of the wound after lavage and debridement
- Leads to a more rapid anatomical and functional recovery than
delayed and secondary closure - Sutures can generally be removed in 1-2 weeks
- If the level of contamination, tissue viability, depth of tissue damage
or vascular supply is questionable, other options should be
considered
15
Q
Delayed primary closure
A
- Wound managed as an open wound until it is clean and without
formation of granulation tissue, then closed - Closure 3-5 days after the emergence of the wound
- Allows for drainage of the wound, a decrease in contamination and
the development of a clear demarcation line between viable and necrotic tissue prior to surgery
