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8,9
population included both primary closures and revision am- and Tribble et al. More specifically, blast injuries and injuries
putation surgeries. Of that, 141 patients did not receive van- with concomitant muscle necrosis were most associated with
comycin, and 82 patients’ amputations were closed with the the development of osteomyelitis. 9
prophylactic application of vancomycin powder. The overall
absolute risk reduction (ARR) was 13% (p = .034), while the Treatment for osteomyelitis is particularly challenging due
ARR for revision amputations was 16% (p = .037). To prevent to the pathogenic organism’s biofilm formation and limited
one infection of deep tissue in amputation surgery, the number bioavailability of the antibiotics in the dense bone tissue in
needed to treat (NNT) was eight, while the NNT for revision an area already subjected to vascular insult. 22, 23 This is where
amputations was seven. The greatest benefit was seen in the vancomycin powder finds its niche. When vancomycin is used
patients who underwent revision amputation surgery with a at the point of injury, the pathogens will not be afforded the
history of infection, with an ARR of 25% and NNT of four time required for biofilm formation. 5, 12, 13 Additionally, this
(p = .01). Initially, in 2009, the surgeon began applying the prophylaxis offers penetration into tissue that has been devas-
vancomycin powder to patients who had previous infections cularized from the trauma. 12
or had been difficult to treat. However, after the clinical evi-
dence suggested improved outcomes, he began treating all pa- TCCC Guidelines for Antibiotic Administration and
tients with it by 2013. 4 Antibiotic Use in Civilian Trauma Care
The current TCCC guidelines, when adhered to, have antibi-
Intrawound vancomycin powder is also being applied pro- otic administration as the eleventh step, following necessary
3
phylactically in total joint arthroplasty. A retrospective inves- stabilization of the patient. This DoD guideline takes into ac-
tigation conducted by Patel et al. explored 460 primary total count time, which is a critical component in getting ahead of
6
hip and knee arthroplasties conducted by one surgeon. Two an imminent infection. A Schauer et al. study from 2007–2016
groups were formed including the vancomycin powder group highlights that while it is the wounded soldier’s responsibility
(n = 348) and the control group without prophylactic antibi- to take their own CWMP, that was done < 1% of the time in
24
otics (n = 112). The vancomycin group’s infection rate was combat. This infers that a more medic driven solution, such as
0.57%, while the control group maintained an infection rate topical application of vancomycin powder, should be pursued.
of 2.7% (p = .031). Another focus of this study was the cost of
the use of antibiotic powder on every patient compared to the As demonstrated by the Lack et al. study, when antibiotics were
cost of one infection. The NNT for this research was 47.5. If applied in a time greater than one hour after a type III open
each patient has $17 of vancomycin powder applied, it would tibia fracture, there was a significantly higher likelihood of in-
17
cost $816 to prevent one infection. When a single hip or knee fection. The local vascular injury complicates the delivery and
joint infection is averaging over $25,000, this cost/benefit bioavailability of these antibiotics in the event of amputations
analysis shows vancomycin powder is a low-cost option with or other open-penetrating trauma wounds. Near immediate
immediate value. 6 and locally administered vancomycin powder mitigates the
variables of time and lack of diffuse local penetration. 12,13
While many studies establish vancomycin’s prophylactic effi-
cacy, the Gande et al. meta-analysis demonstrates the increased Intrawound Vancomycin Powder Use
risk of developing gram-negative and polymicrobial skin and in Orthopedic Wound Models
20
soft tissue infections (SSIs). In this meta-analysis, the con- Vancomycin is a cell wall synthesis inhibitor and has bacteri-
trol group (n = 10,846) had 412 cases of SSI, in comparison cidal and time-dependent properties that give it an advantage
with the vancomycin powder group (n = 8,456), which had when applied early in the process, as demonstrated by Tennent
197 SSIs. In contrast, gram-positive SSIs were much higher et al. 5, 18 Time was one of the variables confirmed to be crucial
in the control group (70% versus 45.1%, p < .05). However, to the elimination of the biofilm formation and establishment
gram-negative and polymicrobial SSIs were significantly more of infection. Vancomycin powder that was delivered to the
prevalent in the vancomycin group (35.8% versus 18.5%, wound at 6 hours was shown to be much more effective in re-
p < .05). The rate of infection in the control group remained ducing the S. aureus bacterial load than waiting until 24 hours
higher (3.8%) than that of the treatment group (2.3%). An- before application. The Caroom et al. study removed the vari-
other contribution that was demonstrated by this analysis was able of time and showed that application of vancomycin pow-
the lack of development of vancomycin-resistant S. aureus in- der was more effective in reducing bacterial growth than the
19
fections in any of these surgeries. 20 vancomycin/tobramycin beads. The advantage that is offered
in using vancomycin powder versus antibiotic beads is that the
vancomycin/tobramycin beads lack the diffuse wound cover-
Discussion
age and some types may have to be later removed, reintroduc-
Blast Injuries and Osteomyelitis ing more opportunities for infection.
Multiple organisms have been cultured from combat wound
infections. While a wide variety of both gram-positive and Results of Vancomycin Administration During Surgery
8
gram-negative microorganisms contaminate wounds, S. au- The evidence for the efficacy of vancomycin powder’s periop-
reus, a gram-positive cocci, is the most commonly isolated erative use following orthopedic injuries has accumulated over
pathogen in recurrent osteomyelitis infections. It has been the past decade. The primary reasons surgeons have used local
21
demonstrated to be a particularly virulent organism and is re- prophylactic antibiotic is that it significantly reduced infection
sponsible for the recurring osteomyelitis infections requiring rates post surgery, reduced financial burden and healthcare
revisional surgeries. Several variables have been found to con- costs, and improved outcomes. These reasons would be po-
5,6
tribute to the likelihood of infection in combat trauma. Both a tentially appealing for the DoD in the reduction of costs and
higher initial severity score and the mechanism of injury have healthcare burden, as well as improved outcomes and return
a direct correlation to infection as established by Mende et al. to duty for their Servicemembers.

78 | JSOM Volume 22, Edition 1 / Sping 2022