Open Wound Management (12) Flashcards
Dr. Thompson
What are some fundamentals of wound management?
- temporarily cover the wound to prevent further trauma or contamination
- assess animal and stabilize
- clip and aseptically prepare the area around the wound
- culture wound before antibiotics
- debride dead tissue and remove foreign debris from the wound
How should you manage the wound?
- lavage the wound
- provide wound drainage
- promote healing by stabilizing and protecting the cleaned wound
- perform appropriate wound closure
What is the Golden Period?
first 6-8 hours between wound contamination at injury and bacterial multiplication to greater than 10^5 CFU per gram of tissue
When is a wound considered infected and not contaminated?
infected when bacterial numbers exceed 10^5 CFU per gram of tissue
What does contamination mean?
presence of microbes on an surface
What does colonization mean?
surface microorganisms are replicating
What does infection mean?
invasion and replication of microbes within the tissues
What is microbial burden?
(number of microorganisms x virulence) / host resistance
What is Class 1 - wound classification?
- 0-6 hours old
- minimal contamination and tissue trauma
What is Class 2 - wound classification?
- 6-12 hours old
- microbial levels may not have reached critical level consistent with development of infection
What is Class 3 - wound classification?
- older than 12 hours
- microbial levels may have reached critical level consistent with development of infection
What are abrasions?
superficial and involve destruction of varying depths of skin by friction from blunt trauma or shearing forces
- sensitive to pressure or touch and bleed minimally
- heal rapidly by repithelialization
What kind of wound?
abrasion
What are puncture wounds?
characterized by small skin openings with deep tissue contamination and damage
wound depth and width vary depending on the velocity and mass of the object creating the wound
What should you be careful of with puncture wounds?
- pieces of hair, skin, and debris can be embedded in wounds
- be careful - don’t know depth or velocity
What are some types of puncture wounds?
- penetrating foreign objects (stick, wire, bone)
- gunshot injuries
- bite wounds
Type of wound?
puncture
What is a laceration?
created by tearing, which damages skin and underlying tissue (muscle, tendons)
What defines something as a laceration?
may be superficial or deep and have irregular edges
- typically, minimal peripheral trauma to the wound edges (unless concurrent avulsion injury)
Type of wound?
laceration
What are avulsions or degloving injuries?
characterized by the tearing of tissues from their attachments and the creation of skin flaps
- exposed wound bed
- common on distal limbs
What are degloving injuries?
avulsion injuries on limbs with extensive skin loss
What is anatomic degloving?
skin and various levels of underlying tissue are torn off
What is physiologic degloving?
skin surface is intact but separated or avulsed from underlying subcutaneous tissue and blood supply
- results in delayed necrosis of the skin
What are thermal burns?
caused by heat or chemicals like fire, cage dryers, heating pads, heat lamps
What happens with deep and extensive burn injuries?
may cause systemic compromise due to
- severe fluid loss
- electrolyte loss
- protein loss
What is increased with thermal burns?
risk of infection and sepsis
What are crush injuries?
can be a combination of other types of wounds with extensive damage and contusions to skin and deeper tissue
What are decubital ulcers?
result of compression of the skin and soft tissues between a bony prominence and a hard surface
What can decubital ulcers result in?
skin loss over a bony prominence, may extend into deeper soft tissue and bone
What are common sites for decubital ulcers? **
- greater trochanter
- lateral elbow
- lateral hock
What is primary wound closure?
wound edges are apposed and allowed to heal by first intention
- occurs in most surgical wounds
- class I and some class II
What are delayed primary closures?
appositional closure within 3-5 days
before granulation tissue has been produced in wound bed
class 2 - mildly contaminated, minimal trauma
What is healing by contraction and epithelialization?
wound left open to heal by contraction and epithelialization
- eventually produces a continuous epithelial surface
- may be inefficient and fail to produce a functional outcome
When is healing by second intention indicated?
- dirty wounds
- contaminated wounds
- traumatized wounds
What is secondary closure - third intention healing?
appositional closure more than 3-5 days after wounding
granulation tissue has formed in the wound bed
When is secondary closure indicated?
severely contaminated, severely traumatized, infected wounds
What happens with secondary closure?
development of granulation tissue in the wound provides a microbial resistant, vascular substrate that facilitates healing
- closure is performed over the granulation tissue
What does immediate wound care involve?
- reduce microbial burden
- prevent further contamination
large volume irrigation - the solution to solution is dilution
What is often required for initial wound inspection and care?
anesthesia
How should you prepare to clip and prep the wound?
applying a sterile, water-soluble lubricant
placing saline-soaked sponges in the wound and covering with a sterile pad or towel
hair may be clipped from the wound margin
After you clip the wound, how should you prep the wound?
use povidone-iodine or chlorhexidine gluconate skin scrubs
What should you not use on open wounds?
alcohol - very damaging to exposed tissue and should be used only on intact skin
What is the preferred lavage solution for initial wound management?
sterile isotonic saline or a balanced electrolyte solution (Lactated Ringer’s)
Why do we do wound lavage?
it reduces bacterial numbers mechanically by loosening and flushing away bacteria and associated necrotic debris
What do noncytotoxic wound cleansers do?
applied to loosen debris and soften necrotic tissue during bandage changes
- surfactant and disrupts the ionic bonding of particles and organisms other than the wound
What in the lavage solution reduces bacterial numbers? What are the drawbacks?
antibiotics or antiseptics - may damage tissue, have little effect on bacteria in established infections
What is the most consistent delivery method to generate 7 or 8 psi for wound lavage?
a 1 liter bag of fluid within a cuff pressurized to 300 mmHg
What are the drawbacks to higher pressure wound irrigation systems?
- drive bacteria and debris into loose tissue planes
- damage underlying tissue
- reduce resistance to infection
How should you lavage this?
1 L of 0.9% saline , maintained at 300 mmHg with extension tubing and an 18-gauge needle
What is debridement?
involves removal of dead or damaged tissue, foreign bodies, and microorganisms that compromise local defense mechanisms and delay healing
What is the goal of debridement?
to obtain fresh clean wound margins and wound bed for primary or delayed closure
The extent of devitalized tissue is usually obvious within ______ of injury
2 days (48 hours)
How do you surgically debride a wound?
excised in layers beginning at the surface and progressing to the depths of the wound
- sharp dissection
- electrosurgery
- laser
How should you debride muscle?
until it bleeds and contracts with appropriate stimuli
How should you debride subcutaneous tissue?
should be avoided as it may delay wound healing
How should you debride fat?
should be liberally excised - easily devascularized and harbors bacteria
How should you debride cutaneous vessels?
must be spared to maintain the viability of overlying skin
When can the entire wound be excised en bloc?
if sufficient healthy tissue surrounds the wound and vital structures can be preserved
What should you do when debriding penetrating wounds or punctures?
it may be necessary to enlarge the wound to asses the extent of injury and allow debridement
When should wounds be closed after surgical debridement?
when it appears healthy or when a bed of healthy granulation tissue has formed
What is autolytic debridement?
accomplished through creation of a moist wound environment to allow endogenous enzymes to dissolve nonviable tissue
How is autolytic debridement accomplished?
hydrophilic, occlusive, or semi occlusive bandages
What is bandage (mechanical) debridement?
dressings that are allowed to dry on the wound, such as wet-to-dry bandages or dry-to-dry bandages
adhere to the wound surface and pull the debris and strip the superficial layers off the wound bed when removed
What do wet-to-dry bandages do?
provide adequate wound protection and coverage, maintain a moist wound environment and absorb moderate amounts of wound exudates
What are mechanical debridement bandage most used?
early stages or in management of wound infection
painful and nonselective
What is enzymatic debridement?
used as an adjunct to wound lavage and surgical debridement
What does enzymatic debridement do?
break down necrotic tissue and liquefy coagulum and bacterial biofilm
What is bio surgical debridement?
maggot therapy
for chronic, non healing wounds
What is maggot therapy best used for?
necrotic, infected, or chronic non healing wounds
What do maggots do?
- remove necrotic tissue
- disinfect the wound
- promote granulation tissue formation
When are antibiotics not normally used with wounds?
if less than 6-8 hours old
When are antibiotics used regarding wounds?
severely contaminated, crushed, or infected wounds
wounds older than 6-8 hours
ultimately based on culture and susceptibility testing
Which kinds of antimicrobials/antibiotics should not be used?
powders
When is triple antibiotic ointment effective?
effective against a broad spectrum of pathogenic bacteria commonly infecting superficial skin wounds
not good against pseudomonas
Triple antibiotic ointment is more effective for _____
preventing infections rather than treating them
What is the drug of choice to treat burn wounds?
silver sulfadiazine
What is silver sulfadiazine effective for?
effective against most gram+ and gram- bacteria and most fungi
serves as an antimicrobial barrier and can penetrate necrotic tissue
What is nitrofurazone?
broad-spectrum antibacterial and hydrophilic properties
What is gentamicin sulfate?
especially effective in controlling gram-negative bacterial growth like pseudomonas
What is cefazolin?
effective antimicrobial against gram+ and gram- organisms
What is mafenide?
topical sulfa compound
- broad spectrum against many gram+ and gram- bacteria
What are the benefits of honey?
- enhancing wound debridement
- reducing edema and inflammation
- promoting granulation tissue formation and epithelialization
- improving wound nutrition
What should honey be used then discontinued?
used: early in the course of wound healing
discontinued: once a healthy granulation bed is present
What are the benefits in using sugar for wounds?
What is the purpose of vacuum-assisted closure?
removes atmospheric pressure
What are the benefits of vacuum-assisted closure?
- increased rate of granulation
- accelerated healing times
- wound cleaning
- improved blood flow
- reduced edema
