Ch 40 open fractures Flashcards
What percentage of traumatic appendicular fractures in dogs and cats are classified as open?
14% dogs
29% cats
What regions of the body are at the highest risk for development of an open fracture after trauma?
Scapula
Radius and Ulna
Tibia and Fibula
Tarsus - At or distal to the tarsus is at the greatest risk
What is name of the classification scheme used for open fractures?
Define each grade
Gustilo-Anderson Open Fracture Classification Scheme
Type 1: Wound <1cm in size, often formed from in-to-out. Surrounding soft tissue is mildly/moderately contused
Type 2: Wound >1cm in size, without extensive soft tissue damage/flaps/avulsions. Often from out-to-in trauma
Type 3: Extensive soft tissue damage
3(a) - Adequate soft tissue coverage of fractured bone despite extensive laceration of flaps
3(b) - Extensive soft tissue loss, periosteal stripping and bone exposure. Usually associated with massive contamination
3(c) - Arterial injury requiring repair
Tx goals (5)
prompt and aggressive debridement of contaminated material and nonviable tissue
wound irrigation
administration of antimicrobials;
restoration of soft tissue coverage to heal
fracture stability
What percentage chlorhexidine solution can be used on the surrounding skin and in the wound?
lavage with?
4% solution for skin
0.05% solution for in wounds - Provide antibacterial activity without causing tissue reactivity
vs sterile isotonic fluid at a desired pressure of 7 to 8 psi.
The authors of a prospective, randomized, double-blinded study found that only 18% of open fracture infections were caused by organisms cultured at the time of initial presentation.
Numerous studies have demonstrated that the organism cultured initially (i.e., the contaminating organism at the time of presentation) is not the organism that ultimately causes infection
In humans, what time period for administration of ABx has been shown to significantly reduce the risk of infection?
Within 3 hours after injury - Reduces infection rates to 4.7% from 7.4%
What is the recommended ABx treatment for each type of open fracture?
Type 1 and 2 - 1st or 2nd gen cephalosporin
Type 3 - Combo of 1st or 2nd gen cephalosporin and a fluoroquinolone
Continuation of antibiotics, should be guided by results of aerobic and anaerobic C&S.
the decision to continue antibiotic therapy is best based on post–surgical debridement samples.
increase the risk of infection include
failure to administer antibiotics
resistant organisms
delay from injury to initiation of antibiotic therapy,
extensive soft tissue trauma
positive culture obtained following debridement-irrigation.
common bacteria
Ab’s covering Gram-positive and Gram-negative aerobic and anaerobic organisms
Staphylococcus spp., Streptococcus spp.,
Klebsiella spp.,
Pseudomonas spp.,
Clostridium spp.,
Enterobacter spp.
Escherichia col
What are the reported infection rates for each type of open fracture in humans?
Type 1 - 1-2%
Type 2 - 2-10%
Type 3 - 10-50%
What are the reported delayed union and non-union rates for each type of open fracture in humans?
Type 1 - 0-5%
Type 2 - 1-14%
Type 3 - 2-37%
In humans, what aspects of treatment of open fractures resulted in fewer infections?
Treating all with emergent surgical debridement
Administering ABx before surgical stabilisation
Primarily closing type I and II Fx
Delayed closure type III
Using no internal fixation (ie. opting for ESF)
Decreased infection rate to 5% from historical control of 12%
What percentage of open Fx infections are cause by the organism which is cultured on presentation?
18%
Suggests that the majority are nosocominal Ix, highlighly the importance of prompt wound care and coverage
How did antibiotic beads effect the infection rate of open fractures in humans?
Combining ABx beads in surgical site with systemic ABx therapy decreased infection rate from 12% to 3.7%
