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sustained in Iraq and Afghanistan, as well as the current in CPG arose from evidence highlighting the need to remove
TCCC guidelines. Studies that explored the prophylactic anti- expanded gram-negative coverage. 16
biotic use of powdered vancomycin in orthopedic extremity
surgeries were included. Additionally, the Defense Technical To extrapolate and supplement from civilian trauma care,
Information Center’s PubDefense was queried to explore on- Lack et al. identified a time greater than 66 minutes from
going clinical trials as well as research that has been conducted injury to the administration of antibiotics as a predictor of
on this topic. Lastly, primary research on animal trials, and infection in type III open tibia fractures with an odds ratio
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retrospective and prospective studies exploring the efficacy of of 3.78 (95% CI, 1.16–12.31; p = .03). This retrospective
prophylactic vancomycin powder, use have also been incorpo- study examined patients (n = 137) who had type III open tibia
rated in this work. fractures. The outcome measured was the presence of deep in-
fection within 90 days of the fracture. The variables of age,
smoking, diabetes, and injury severity score were shown to
Results
have minimal influence upon infection rates. They further as-
Blast Injuries and Osteomyelitis sessed that outcomes for these types of fractures would be im-
Throughout the duration of the recent conflicts in Afghani- proved with antibiotic prophylaxis occurring within one hour
stan and Iraq, substantial research has been conducted re- of the incident. This continues to support the notion that time
garding the infectious pathogens found post-injury. Casualties is a critical variable in the avoidance of infection. 17
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that suffered blast injuries were at a higher risk for infection.
Blast injuries were also associated with the development of Intrawound Vancomycin Powder Use
osteomyelitis (p = .001) as demonstrated by Tribble et al. in in Orthopedic Wound Models
a case-control analysis of 215 patients with combat-related Using orthopedic wound models, Tennent et al. analyzed
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open tibia fractures. Of these 215 patients that were evalu- debridement and irrigation (D&I) as the sole treatment in
9
ated, 130 cases of osteomyelitis were identified. Osteomyeli- trauma wounds, in contrast with vancomycin powder as an
tis has been identified as the primary complication associated adjunct to debridement and irrigation. An essential variable
5
with combat-related extremity wounds, with 15% of patients to this study was time, with the treatments being performed
developing this infection and 17% of patients having recur- at either 6 hours or 24 hours. This study examined 54 rat
rent osteomyelitis. A retrospective cohort study conducted femurs contaminated with S. aureus (an osteomyelitis isolate).
1
by Yun et al. identified 110 patients with orthopedic injuries The research demonstrated statistically significant results
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from early (2003–2006) in the Iraq and Afghanistan wars. (p < .001) with the bacterial load being reduced in the bone
These 110 patients underwent hospitalization 139 times for when vancomycin was applied 6 hours after contamination as
osteomyelitis. The most common pathogens identified at the an adjunct to D&I. This was in contrast to solely D & I. When
first level of higher care include Acinetobacter spp., Klebsiella the powder was administered at 24 hours following the bac-
pneumoniae, and Pseudomonas aeruginosa. The recurrent terial contamination, the infection was not reduced. This was
10
infections were primarily gram-positive organisms: Staphylo- most likely due to the formation of the bacterial biofilm. A
coccus aureus, methicillin-susceptible S. aureus, and methicil- significant residual amount of vancomycin powder remained
lin-resistant S. aureus (MRSA). 10 present in the animal’s musculature for up to 14 days follow-
ing the inoculation. 5
An additional variable is the virulence of S. aureus, P. aeru-
ginosa, and E. coli and their biofilm formation. When given Likewise, Caroom et al. examined 45 rats with simulated
19
enough time, these organisms adhere to one another and to open femur fractures that were inoculated with S. aureus.
their environment when they begin to produce an extracellu- This study was different than the Tennent et al. study, in that
5
lar polymeric substance (EPS). 11–15 This EPS formation confers time was not the variable. The variables in this study were
defenses to each bacterium contained therein, providing recal- the three treatment modalities, all of which were conducted
citrance to host defenses and antimicrobial treatment. Biofilm at 6 hours post-wound. These included D&I alone (control
5
formation is of particular importance in the destructiveness group), D&I plus vancomycin and tobramycin beads, or D&I
14
of osteomyelitis and the threat it poses to further limb loss. plus 10mg of intrawound vancomycin powder. The results for
While the recognition of biofilms and their role in chronic in- this study showed that the placement of intrawound vancomy-
fections is becoming more evident, a clear picture of their func- cin powder significantly reduced bacterial growth (p < .0001)
tion in combat trauma is not yet known. 1 when compared with the control group. 19
TCCC Guidelines for Antibiotic Administration and An unexpected benefit of prophylactic vancomycin powder
16
Antibiotic Use in Civilian Trauma Care administration was researched by Seavey et al. in 2017. Het-
Prompt use of antibiotics at the point of injury is a part of the erotopic ossification (HO) commonly occurs following blast
standard operating procedure for combat medics on the bat- injuries in up to 65% of patients. The early use of this powder
tlefield. Point of injury antimicrobial treatment by the combat in the rat models lead to a statistically significant reduction
medic provider is advised in the case of all open penetrating in HO. Time was again the critical variable. The earlier the
trauma wounds on the battlefield. The medic may adminis- vancomycin powder was applied, the higher likelihood both
ter antibiotics, but it is the wounded soldier’s responsibility infection and HO would be prevented. 16
to take their personally issued Combat Wound Medication
Pack (CWMP). The current standard of care is moxifloxacin, Results of Vancomycin Administration During Surgery
400mg by mouth if the patient can swallow or ertapenem, or The orthopedic realm has been prophylactically applying
1g IV / intramuscular (IM) if the patient is unconscious or in vancomycin powder before closing surgical wounds for over
shock. These guidelines have been reached through a decade a decade. From 2009–2015, in a Pavey et al. study, one sur-
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of evolution with the last major updates in 2012. The change geon conducted 223 (n = 223) lower limb amputations. This
Efficacy of Vancomycin Powder on the Battlefield | 77