Experience with intrawound vancomycin powder for posterior cervical fusion surgery

Impact of Plastic Surgery and an Enhanced Prophylaxis Protocol on Cervical Spine Surgery Infection

Background: Reduction of surgical site infections (SSIs) is important in improving cervical spine surgery outcomes. Plastic surgery involvement and an enhanced modified prophylaxis protocol may reduce infection rates. Methods: A total of 962 cervical spine operations were conducted by a single surgeon (TFC). An enhanced modified prophylaxis protocol and plastic surgery were used in some operations. Differences in infection rates, surgical approach, previous operations, prophylaxis use, and plastic surgery involvement were compared using Fisher's exact tests and multivariate linear regression. Results: Four patients (0.42%) experienced SSIs. All 4 infections involved the standard protocol, posterior approach, and did not involve plastic surgery. The infection rate was lower in the enhanced protocol group when compared to the standard protocol (β -0.78, 95% CI -1.23 to -0.33, P = .0008). The enhanced protocol group had an increased percentage of operations with plastic surgery (β 0.19, 95% CI 0.10 to 0.28, P < .0001). The infection rate among the plastics group was 0.00% compared to 0.60% for the non-plastics group (P = .32). The plastics group had a lower rate of anterior approach when compared to the non-plastics group (β -0.20, 95% CI -0.24 to -0.15, P = .049). Among the posterior approach group, procedures with plastic surgery had an infection rate of 0.00% compared to 2.53% without plastic surgery (P = .13). Conclusion: The enhanced protocol was associated with a lower SSI rate and increased plastic surgery involvement. Posterior approaches were associated with increased infection rates and the likelihood of utilizing plastic surgery. Both the enhanced protocol and plastic surgery may decrease infection.

Incidence and risk factors of surgical site infection following cervical laminoplasty: A retrospective clinical study

There are many debates regarding the risk factors of surgical site infection (SSI) following posterior cervical surgery in previous studies. And, till now there is no such a study to examine cervical laminoplasty surgery. From January 2011 through October 2021, a total of 405 patients who were treated with unilateral open-door laminoplasty surgeries were enrolled in this study. We divided the patients into the SSI group and the non-SSI group and compared their patient-specific and procedure-specific factors. Univariate and multiple logistic regression analysis were performed to determine the risk factors. Of the 405 patients, 20 patients had SSI. The rate of SSI found to be 4.93%. There were significant differences between groups in the thicker subcutaneous fat thickness (FT) (p < 0.001), the higher ratio of subcutaneous FT to muscle thickness (MT) (p < 0.001), the higher preoperative Japanese Orthopaedic Association (JOA) Scores (p < 0.003), the decreased preoperative serum albumin (p < 0.001), the more postoperative drainage (p < 0.05) and the longer time of draining (p < 0.001). Logistic regression analysis of these differences showed that the higher ratio of subcutaneous FT/MT, the higher preoperative JOA scores, the decreased preoperative serum albumin and the longer time of draining were significantly related to SSI (p < 0.05). The higher ratio of subcutaneous FT/MT, the higher preoperative JOA scores, the decreased preoperative serum albumin and the longer time of draining are identified as the independent risk factors of SSI in cervical laminoplasty. Identification of these risk factors could be useful in reducing the SSI incidence and patients counselling.

Prevention of Surgical Site Infections in Spine Surgery: An International Survey of Clinical Practices Among Expert Spine Surgeons

STUDY DESIGN

Questionnaire-based survey.

OBJECTIVES

Surgical site infection (SSI) is a common complication in spine surgery but universal guidelines for SSI prevention are lacking. The objectives of this study are to depict a global status quo on implemented prevention strategies in spine surgery, common themes of practice and determine key areas for future research.

METHODS

An 80-item survey was distributed among spine surgeons worldwide via email. The questionnaire was designed and approved by an International Consensus Group on spine SSI. Consensus was defined as more than 60% of participants agreeing to a specific prevention strategy.

RESULTS

Four hundred seventy-two surgeons participated in the survey. Screening for Staphylococcus aureus (SA) is not common, whereas preoperative decolonization is performed in almost half of all hospitals. Body mass index (BMI) was not important for surgery planning. In contrast, elevated HbA1c level and hypoalbuminemia were often considered as reasons to postpone surgery. Cefazoline is the common drug for antimicrobial prophylaxis. Alcohol-based chlorhexidine is mainly used for skin disinfection. Double-gloving, wound irrigation, and tissue-conserving surgical techniques are routine in the operating room (OR). Local antibiotic administration is not common. Wound closure techniques and postoperative wound dressing routines vary greatly between the participating institutions.

CONCLUSIONS

With this study we provide an international overview on the heterogeneity of SSI prevention strategies in spine surgery. We demonstrated a large heterogeneity for pre-, peri- and postoperative measures to prevent SSI. Our data illustrated the need for developing universal guidelines and for testing areas of controversy in prospective clinical trials.

Intra-wound versus systemic vancomycin for preventing surgical site infection induced by methicillin-resistant S. aureus after spinal implant surgery in a rat model

BACKGROUND

Systemic vancomycin administration pre-operatively for the infection prophylaxis of spinal implant surgery remains unsatisfactory. This study aimed to explore the efficacy and dosage of local use of vancomycin powder (VP) in preventing surgical site infections after spinal implant surgery in a rat model.

METHODS

Systemic vancomycin (SV; intraperitoneal injection, 88 mg/kg) or intraoperative intra-wound VP (VP0.5: 44 mg/kg, VP1.0: 88 mg/kg, VP2.0: 176 mg/kg) was applied after spinal implant surgery and methicillin-resistant S. aureus (MRSA; ATCC BAA-1026) inoculation in rats. General status, blood inflammatory biomarkers, microbiological and histopathological evaluation were performed during 2 weeks post-surgery.

RESULTS

No post-surgical deaths, wound complications and obvious signs of vancomycin adverse effects were observed. Bacterial counts, blood and tissue inflammation were reduced in the VP groups compared with the SV group. VP2.0 group showed better outcomes in weight gain and tissue inflammation than the VP0.5 and VP1.0 group. Microbial counts indicated that no bacteria survived in the VP2.0 group, whereas MRSA was detected in VP0.5 and VP1.0 groups.

CONCLUSIONS

Intra-wound VP may be more effective than systemic administration in preventing infection caused by MRSA (ATCC BAA-1026) after spinal implant surgery in a rat model.

Effect of powdered vancomycin on stopping surgical site wound infections in neurosurgery: A meta-analysis

We performed a meta-analysis to evaluate the effect of powdered vancomycin on stopping surgical site wound infections in neurosurgery. A systematic literature search up to July 2022 was performed and 24 137 subjects with neurosurgery at the baseline of the studies; 10 496 of them were using the powdered vancomycin, and 13 641 were not using the powdered vancomycin as a control. Odds ratio (OR) with 95% confidence intervals (CIs) were calculated to assess the effect of powdered vancomycin on stopping surgical site wound infections in neurosurgery using dichotomous methods with a random or fixed-effect model. The powdered vancomycin had significantly lower surgical site wound infections after spinal surgery (OR, 0.53; 95% CI, 0.41-0.70, P < .001), deep surgical site wound infections after spinal surgery (OR, 0.45; 95% CI, 0.35-0.57, P < .001), superficial surgical site wound infections after spinal surgery (OR, 0.60; 95% CI, 0.43-0.83, P = .002), and surgical site wound infections after cranial surgery (OR, 0.37; 95% CI, 0.22-0.61, P < .001) compared to control in subjects with neurosurgery. The powdered vancomycin had significantly lower surgical site wound infections after spinal surgery, deep surgical site wound infections after spinal surgery, superficial surgical site wound infections after spinal surgery, and surgical site wound infections after cranial surgery compared to control in subjects with neurosurgery. The analysis of outcomes should be done with caution even though the low number of studies with low sample size, 3 out of the 42 studies, in the meta-analysis, and a low number of studies in certain comparisons.

Prophylactic Application of Vancomycin Powder in Preventing Surgical Site Infections After Spinal Surgery

OBJECTIVE

We sought to analyze the preventive effect of local vancomycin powder application on surgical site infection (SSI) in spinal surgeries and provide the basis for future clinical practice.

METHODS

Through PubMed, Medline, Elsevier, and the Cochrane Library, with MeSH words "vancomycin powder," "local/intraoperative/topical/intra-wound," "spine/spinal/lumbar/cervical/thoracolumbar," "surgery," "infection," and "SSI," we searched for case-control research papers on the impact of prophylactic application of vancomycin powder on the incidence of SSI and compared the rate of infection using RevMan 5.3 meta-analysis software.

RESULTS

A total of 1950 publications were found using the mesh words, and 50 of those studies were selected for final analysis. There were 34,301 cases in total, including 14,793 cases in vancomycin group and 19,508 cases in the control group. Results of meta-analysis showed that the incidence of SSI was significantly lower in the prophylactic vancomycin powder group than the control group (P < 0.001). Further subgroup analysis showed that the incidence of SSI was significantly lower in the prophylactic vancomycin powder group than the control group in spine surgeries with internal fixation, deformity correction, and deep tissue infections (P < 0.001). Meanwhile, there were no significant differences between the 2 groups concerning patients undergoing noninstrumented spine surgeries and the incidence of superficial tissue infection.

CONCLUSIONS

Overall, prophylactic application of vancomycin powder in spinal surgery can significantly reduce the incidence of SSI in deep tissues, and this effect is more prominent in patients undergoing internal fixation and deformity correction surgeries.

Use of an intraoperative sodium oxychlorosene-based infection prevention protocol to safely decrease postoperative wound infections after spine surgery

OBJECTIVE

Postoperative infection remains prevalent after spinal surgical procedures. Institutional protocols for infection prevention have improved rates of infection after spine surgery. However, prior studies have focused on only elective surgical patients. The aim of this study was to determine the efficacy of a multiinstitutional intraoperative sodium oxychlorosene-based infection prevention protocol for decreasing rate of infection after instrumented spinal surgery.

METHODS

A retrospective analysis was performed at two tertiary care institutions with level I trauma programs, and patients who underwent posterior instrumented spinal fusion between January 1, 2011, and May 31, 2019, were included. Postoperative deep wound infection rates were captured before and after implementation of a multiinstitutional infection prevention protocol. Possible adverse outcomes related to infection prevention techniques were also examined. In addition, consecutive patients treated from January 1, 2018, to May 31, 2019, were prospectively included in a database to collect preoperative and postoperative spine-specific quality of life measures and to assess the impact of postoperative infection on quality of life.

RESULTS

A total of 5047 patients fit the inclusion criteria. Of these, 1043 patients underwent surgery prior to protocol implementation. The infection rate of this cohort (3.5%) decreased significantly after protocol implementation (1.2%, p < 0.001). Postoperative sterile seroma rates did not differ between the preprotocol and postprotocol groups (0.7% vs 0.7%, p = 0.5). In the 1031 patients who underwent surgery between January 2018 and May 2019, the fusion rate was 89.2%. Quality of life outcomes between patients with infection and those without infection were similar, although statistical power was limited owing to the low rate of infection. Notably, 2 of 10 patients who developed deep wound infection died of infection-related complications.

CONCLUSIONS

An intraoperative sodium oxychlorosene-based infection prevention protocol helped to significantly decrease the rate of infection after spine surgery without negatively impacting other postoperative procedure-related metrics. Postoperative wound infection may be associated with higher-than-expected rate of postoperative mortality.

Effectiveness of topical vancomycin in the prevention of spinal surgical site infections: a retrospective cohort study

BACKGROUND

The risk of surgical site infections (SSIs), particularly methicillin-resistant Staphylococcus aureus (MRSA) SSIs, after spinal surgeries is one of the most daunting experiences to patients and surgeons. Some authors suggest applying vancomycin powder on the wound before skin closure to minimize the risk of SSIs; however, this practice is not supported by well-established evidence. This study sought to assess the effectiveness of topical (i.e. intra-wound) vancomycin in minimizing the risk of SSIs in patients who underwent spinal surgeries at a Saudi hospital.

METHODS

A retrospective cohort study was conducted using the hospital database. Patients who underwent spinal surgeries from the period of 09/2013 to 09/2019 were included and followed up (observed from the time of the surgery) to 30 days (surgeries without implants) or 90 days (with implants). The odds ratio (OR) of the primary outcome between vancomycin treated versus non-treated patients was estimated using a logistic regression model adjusting for the measured confounders. A sensitivity analysis was conducted using propensity score analysis (inverse probability of treatment weighting [IPTW] with stabilized weights) to control for confounding by indication. All study analyses were completed using RStudio Version 1.2.5033.

RESULTS

We included 81 vancomycin treated vs. 375 untreated patients with 28 infections (8/81 vs. 20/375; respectively). The adjusted OR of SSIs between the two groups was 0.40 (95% confidence interval [CI] 0.11 to 1.34). The result of the propensity score analysis was consistent (OR: 0.97 [95% CI 0.35 to 2.68]).

CONCLUSIONS

We could not find a lower association of SSIs with intra-wound vancomycin in patients who underwent spinal surgeries. Further studies are needed to assess benefits of using topical vancomycin for this indication vs. the risk of antimicrobial resistance.

Invasive Staphylococcus aureus Infection among Patients Undergoing Elective, Posterior, Instrumented Spinal Fusion Surgeries: A Retrospective Cohort Study

Background: Post-surgical invasive Staphylococcus aureus infections among spinal fusion patients are serious complications that can worsen clinical outcomes and increase healthcare utilization. Risk of such infections at the population level remains unknown. This study assessed the post-surgical risk of invasive Staphylococcus aureus infections among patients undergoing elective posterior instrumented spinal fusion surgeries in 129 U.S. hospitals. Patients and Methods: This retrospective cohort study analyzed adult patients ≥18 years of age who underwent thoracolumbar/lumbar and cervical fusion surgeries during 2010 - 2014 using the Premier Healthcare Database, the largest hospital discharge database in the United States. Risks of blood stream infection (BSI), deep or organ/space surgical site infections (SSI) caused by Staphylococcus aureus during 90 and 180 days post-index surgery were estimated. Infections were identified based on positive culture results, related International Classification of Diseases, Ninth Revision (ICD-9) procedure codes, and specific claims information. Results: Among 11,236 patients with thoracolumbar/lumbar fusion, 90- and 180-day BSI/SSI infection risks were higher for multilevel than single level fusion (90-day, 1.52% vs. 1.07%, p = 0.05; 180-day, 1.66% vs. 1.07%, p = 0.014). Among 1,641 patients with cervical fusion, 90- and 180-day BSI/SSI infection risks were also higher in multilevel fusions but not statistically significant (90-day, 1.66% vs. 0.52%, p = 0.350; 180-day, 1.80% vs. 0.51%, p = 0.241). The risk for SSI/BSI was more than twice as high among multilevel thoracolumbar/lumbar fusion patients with more than two comorbidities than those with no comorbidity at both 90-day (2.78% vs. 1.00%, p < 0.05) and 180-day (3.01% vs. 1.10%, p < 0.05). Similar trend without statistical significance was seen in multilevel cervical fusion cohort (90-day, 2.91% vs. 1.25%, p > 0.05; 180-day, 3.88% vs. 1.41%, p > 0.05). Conclusions: The risk of BSI/SSI infection for elective posterior instrumented spinal fusions ranged between 0.5% and 2%. Higher risk was observed in multilevel thoracolumbar/lumbar surgery, with infection risk greatest in patients with more than two comorbidities. These real-world findings highlight the need for additional measures, in addition to antibiotic prophylaxis, to reduce invasive Staphylococcus aureus infections in this setting.

A meta-analysis of the local application of vancomycin powder to prevent surgical site infection after spinal surgeries

Objective

This study aimed to systematically analyze the effectiveness and safety of the local application of vancomycin powder to prevent surgical site infection (SSI) after spinal surgeries and provide guidance for clinical practice.

Methods

Two researchers independently searched PubMed, Web of Science, Elsevier, and China National Knowledge Infrastructure using the MeSH terms “spinal surgery,” “vancomycin,” “local,” “topical,” “prophylactic,” “surgical site infection,” and “SSI” to identify studies published between January 2010 and January 2020 on the local application of vancomycin powder for preventing SSI after spinal surgeries. The outcome assessment indicators were analyzed using RevMan 5.3 software.

Results

Three randomized controlled trials, two prospective studies, and 26 retrospective studies were included in the current research. The results of the meta-analysis revealed significant differences between the vancomycin and control groups (non-vancomycin group) concerning the incidence of SSI (risk ratio = 0.39, 95% confidence interval = 0.28–0.55, Z = 5.46), indicating that local application of vancomycin powder can significantly reduce the incidence of SSI.

Conclusion

Local application of vancomycin powder is an effective and safe method to prevent SSI after spinal surgeries.

Intrawound vancomycin application after spinal surgery: a propensity score-matched cohort analysis

OBJECTIVE

Surgical site infection (SSI) following spine surgery is associated with increased morbidity and healthcare costs. In an effort to reduce SSI rates, the application of intrawound vancomycin powder has gained popularity. However, there is limited high-quality evidence to support the safety and efficacy of this practice. The authors sought to determine if intrawound application of vancomycin powder improves 90-day overall SSI rates.

METHODS

The authors performed a retrospective, vancomycin exposure-matched cohort study at a single tertiary care hospital over 21 months. They included all patients undergoing elective spinal surgery and stratified the patients into two groups: those who received intrawound vancomycin powder application and those who received no application of vancomycin powder. The primary outcome of interest was the 90-day overall SSI rate. Secondary outcomes included rates of superficial SSI, deep SSI, wound disruption, and a post hoc analysis of the microbiology and minimum inhibitory concentrations. Baseline patient demographics, clinical presentation, comorbidities, perioperative factors, and 90-day postoperative outcomes were manually abstracted from patient charts. To mitigate bias, we performed 1:1 matching after calculating propensity scores and identified 1 patient from the no-vancomycin cohort for each patient in the vancomycin cohort.

RESULTS

A total of 997 patients met our inclusion criteria (473 patients receiving vancomycin and 524 patients not receiving vancomycin). Propensity score matching produced 221 matched pairs. Risk-adjusted analysis demonstrated similar overall SSI rates between the groups (OR 1.9, p = 0.329). On unadjusted analysis, the overall 90-day SSI rate was greater in the vancomycin group (n = 10 [4.5%]) than in the no-vancomycin group (n = 5 [2.3%]) (p < 0.001), as were the superficial SSI rate (7 [3.2%] vs 4 [1.8%], p < 0.001), deep SSI rate (3 [1.4%] vs 1 [0.5%], p < 0.001), and wound disruption rate (5 [2.3%] vs 1 [0.5%], p < 0.001). No cultured isolate demonstrated vancomycin resistance.

CONCLUSIONS

The authors observed no difference in SSI rates after the intrawound application of vancomycin powder during spine surgery. Vancomycin use did not contribute to antimicrobial resistance; however, it may select out gram-negative bacteria and increase rates of wound disruption.

Topical Vancomycin Powder and Dilute Povidone-Iodine Lavage Reduce the Rate of Early Periprosthetic Joint Infection After Primary Total Knee Arthroplasty

BACKGROUND

Vancomycin powder and dilute povidone-iodine lavage (VIP) was introduced to reduce the incidence of periprosthetic joint infection (PJI) in high-risk total knee arthroplasty (TKA) patients. We hypothesize that VIP can reduce the incidence of early PJI in all primary TKA patients, regardless of preoperative risk.

METHODS

An infection database of primary TKAs performed before a VIP protocol was implemented (January 2012-December 2013), during a time when only high-risk TKAs received VIP (January 2014-December 2015), and when all TKAs received VIP (January 2016-September 2019) at an urban, university-affiliated, not-for-profit orthopedic hospital was retrospectively reviewed to identify patients with PJI. Criteria used for diagnosis of PJI were the National Healthcare Safety Network and Musculoskeletal Infection Society guidelines.

RESULTS

VIP reduced early primary TKA PJI incidence in both the high-risk and all-risk cohorts compared with the pre-VIP cohort by 44.6% and 56.4%, respectively (1.01% vs 0.56% vs 0.44%, P = .0088). In addition, after introducing VIP to all-risk TKA patients, compared with high-risk TKA patients, the relative risk of PJI dropped an additional 21.4%, but this finding did not reach statistical significance (0.56% vs 0.44%, P = .4212). There were no demographic differences between the 3 VIP PJI cohorts.

CONCLUSION

VIP is associated with a reduced early PJI incidence after primary TKA, regardless of preoperative risk. With the literature supporting its safety and cost-effectiveness, VIP is a value-based intervention, but given the nature of this historical cohort study, a multicenter randomized controlled trial is underway to definitively confirm its efficacy.

[The effectiveness of local application of vancomycin powder in the prevention of surgical site infections in spine surgery: a meta-analysis]

OBJECTIVE

To perform a meta-analysis of studies examining the effectiveness of the local application of vancomycin powder for the prophylaxis of surgical site infections (SSIs) in spine surgery.

MATERIAL AND METHODS

Retrospective cohort studies and prospective randomized clinical trials were searched for in the Pubmed, EMBASE, Cochrane Library and eLibrary databases published from 2008 to December 2018. For the resulting variables, the odds ratio and 95% confidence interval were calculated using random and fixed effects models. Estimation of the degree of heterogeneity is estimated using the coefficient I². Statistically significant differences were considered differences p<0.05.

RESULTS

The meta-analysis included 28 clinical studies that included the results of the local application of vancomycin powder in 17,469 patients after performing various spinal surgical interventions. Two publications had a prospective, randomized, controlled study design. Topical application of vancomycin powder reduces the incidence of SSIs after spine surgery (p<0.0001). The use of vancomycin powder reduces the incidence of SSIs in patients operated on with stabilizing implants (p=0.004). On the other hand, the topical application of vancomycin powder did not affect the prevalence of SSIs in respondents who were operated on without the use of stabilizing implants (p=0.12) or due to deformities of the spine (p=0.06).

CONCLUSION

Topical application of vancomycin powder is highly effective in preventing the development of SSIs in patients after spinal surgical interventions.

Progress not panacea: vancomycin powder efficacy and dose evaluated in an in vivo mouse model of spine implant infection

BACKGROUND

Intrawound vancomycin powder (VP) has been rapidly adopted in spine surgery with apparent benefit demonstrated in limited, retrospective studies. Randomized trials, basic science, and dose response studies are scarce.

PURPOSE

This study aims to test the efficacy and dose effect of VP over an extended time course within a randomized, controlled in vivo animal experiment.

STUDY DESIGN/SETTING

Randomized controlled experiment utilizing a mouse model of spine implant infection with treatment groups receiving vancomycin powder following bacterial inoculation.

METHODS

Utilizing a mouse model of spine implant infection with bioluminescent Staphylococcus aureus, 24 mice were randomized into 3 groups: 10 infected mice with VP treatment (+VP), 10 infected mice without VP treatment (No-VP), and 4 sterile controls (SC). Four milligrams of VP (mouse equivalent of 1 g in a human) were administered before wound closure. Bioluminescence imaging was performed over 5 weeks to quantify bacterial burden. Electron microscopy (EM), bacterial colonization assays (Live/Dead) staining, and colony forming units (CFU) analyses were completed. A second dosing experiment was completed with 34 mice randomized into 4 groups: control, 2 mg, 4 mg, and 8 mg groups.

RESULTS

The (+VP) treatment group exhibited significantly lower bacterial loads compared to the control (No-VP) group, (p<.001). CFU analysis at the conclusion of the experiment revealed 20% of mice in the +VP group and 67% of mice in the No-VP group had persistent infections, and the (+VP) treatment group had significantly less mean number of CFUs (p<.03). EM and Live/Dead staining revealed florid biofilm formation in the No-VP group. Bioluminescence was suppressed in all VP doses tested compared with sterile controls (p<.001). CFU analysis revealed a 40%, 10%, and 20% persistent infection rate in the 2 mg, 4 mg, and 8 mg dose groups, respectively. CFU counts across dosing groups were not statistically different (p=.56).

CONCLUSIONS

Vancomycin powder provided an overall infection prevention benefit but failed to eradicate infection in all mice. Furthermore, the dose when halved also demonstrated an overall protective benefit, albeit at a lower rate.

CLINICAL SIGNIFICANCE

Vancomycin powder is efficacious but should not be viewed as a panacea for perioperative infection prevention. Dose alterations can be considered, especially in patients with kidney disease or at high risk for seroma.

Current Strategies in Prevention of Postoperative Infections in Spine Surgery

STUDY DESIGN

Narrative review.

OBJECTIVES

Postoperative surgical site infections (SSIs) are among the most common acute complications in spine surgery and have a devastating impact on outcomes. They can lead to increased morbidity and mortality as well as greater economic burden. Hence, preventive strategies to reduce the rate of SSIs after spine surgery have become vitally important. The purpose of this article was to summarize and critically analyze the available evidence related to current strategies in the prevention of SSIs after spine surgery.

METHODS

A literature search utilizing Medline database was performed. Relevant studies from all the evidence levels have been included. Recommendations to decrease the risk of SSIs have been provided based on the results from studies with the highest level of evidence.

RESULTS

SSI prevention occurs at each phase of care including the preoperative, intraoperative, and postoperative periods. Meticulous patient selection, tight glycemic control in diabetics, smoking cessation, and screening/eradication of Staphylococcus aureus are some of the main preoperative patient-related preventive strategies. Currently used intraoperative measures include alcohol-based skin preparation, topical vancomycin powder, and betadine irrigation of the surgical site before closure. Postoperative infection prophylaxis can be performed by administration of silver-impregnated or vacuum dressings, extended intravenous antibiotics, and supplemental oxygen therapy.

CONCLUSIONS

Although preventive strategies are already in use alone or in combination, further high-level research is required to prove their efficacy in reducing the rate of SSIs in spine surgery before evidence-based standard infection prophylaxis guidelines can be built.

Spinal Fusion Surgery and Local Antibiotic Administration: A Systematic Review on Key Points From Preclinical and Clinical Data

STUDY DESIGN

Systematic review.

OBJECTIVE

The present review of clinical and preclinical in vivo studies focused on the local antibiotic administration for surgical site infection (SSI) in spinal fusion procedures and identifying new approaches or research direction able to release antibiotics in the infected environment.

SUMMARY OF BACKGROUND DATA

SSI is a severe complication of spinal fusion procedures that represents a challenging issue for orthopedic surgeons. SSIs can range from 0.7% to 2.3% without instrumentation up to 6.7% with the use of instrumentation with significant implications in health care costs and patient management.

METHOD

A systematic search was carried out by two independent researchers according to the PRISMA statement in three databases (www.pubmed.com, www.scopus.com and www.webofknowledge.com) to identify preclinical in vivo and clinical reports in the last 10 years. Additionally, to evaluate ongoing clinical trials, three of the major clinical registry websites were also checked (www.clinicaltrials.gov, www.who.int/ictrp, https://www.clinicaltrialsregister.eu).

RESULTS

After screening, a total of 43 articles were considered eligible for the review: 36 clinical studies and seven preclinical studies. In addition, six clinical trials were selected from the clinical registry websites.

CONCLUSION

The results reported that the topical vancomycin application seem to represent a strategy to reduce SSI incidence in spine surgery. However, the use of local vancomycin as a preventive approach for SSIs in spine surgery is mostly based on retrospective studies with low levels of evidence and moderate/severe risk of bias that do not allow to draw a clear conclusion. This review also underlines that several key points concerning the local use of antibiotics in spinal fusion still remains to be defined to allow this field to make a leap forward that would lead to the identification of specific approaches to counteract the onset of SSIs.

LEVEL OF EVIDENCE

4.

Complications following posterior cervical decompression and fusion: a review of incidence, risk factors, and prevention strategies

Posterior cervical decompression and fusion (PCF) is a common surgical technique used to treat various cervical spine pathologies. However, there are various complications associated with PCF that can negatively impact patient outcome. We performed a comprehensive literature review to identify the most common complications following PCF using PubMed, Cochrane Database of Systematic Reviews, and Google Scholar. The overall complication rates of PCF are estimated to range from about 15% to 25% in the current literature. The most common immediate complications include acute blood loss anemia, surgical site infection (SSI), C5 palsy, and incidental durotomy; the most common long-term complications include adjacent segment degeneration, junctional kyphosis, and pseudoarthrosis. Three principal mechanisms are thought to contribute to complications. First, higher number of fusion levels, obesity, and more complex pathologies can increase the invasiveness of the planned procedure, thus increase complications. Second, wound healing and arthrodesis may be impaired due to poor blood flow due to various patient factors such as smoking, diabetes, increased frailty, steroid use, and other medical comorbidities. Finally, increased biomechanical stress on the upper instrumented vertebra (UIV) and lowest instrumented vertebra (LIV) may predispose patient to chronic degeneration and result in adjacent level degeneration and/or junctional problems. Reducing the modifiable risk factors pre-operatively can decrease the overall complication rate. Neurologic deficits may be reduced with adequate intraoperative decompression of neural elements. SSI may be reduced with meticulous wound closure that minimizes dead space, drain placement, and the use of intra-wound antibiotics. Careful design of the fusion construct with consideration in spinal alignment and biomechanics can help to reduce the rate of junctional problems. Spine surgeons should be aware of these complications associated with PCF and the corresponding prevention strategies optimize patient outcomes.

Double-blind randomized clinical trial of vancomycin in spinal arthrodesis: no effects on surgical site infection

OBJECTIVE

Surgical site infection (SSI) results in high morbidity and mortality in patients undergoing spinal fusion. Using intravenous antibiotics in anesthesia induction reduces the rate of postoperative infection, but it is not common practice to use them topically, despite recent reports that this procedure helps reduce infection. The objective of this study was to determine whether the topical use of vancomycin reduces the rate of postoperative SSI in patients undergoing thoracolumbar fusion.

METHODS

A randomized, double-blind clinical trial in a single hospital was performed comparing vancomycin and placebo in thoracolumbar fusion patients.

RESULTS

A total of 96 patients were randomized to placebo or vancomycin treatment. The mean patient age was 43 ± 14.88 years, 74% were male, and the most common etiology was fall from height (46.9%). The overall rate of postoperative SSI was 8.3%, and no difference was found between the groups: postoperative infection rates in the vancomycin and placebo groups were 8.2% and 8.5% (relative risk [RR] of SSI not using vancomycin 1.04, 95% confidence interval [CI] 0.28-3.93, p = 0.951), respectively. Patients with diabetes mellitus had higher SSI rates (RR 8.98, 95% CI 1.81-44.61, p = 0.007).

CONCLUSIONS

This is the first double-blind randomized clinical trial to evaluate the effects of topical vancomycin on postoperative infection rates in thoracolumbar fusion patients, and the results did not differ significantly from placebo.Clinical trial registration no.: RBR-57wppt (ReBEC; http://www.ensaiosclinicos.gov.br/).

Does the Application of Topical Intrawound Vancomycin Powder Affect Deep Surgical Site Infection and the Responsible Organisms after Spinal Surgery?: A Retrospective Case Series with a Historical Control Group

STUDY DESIGN

Retrospective case series with a historical control group.

PURPOSE

To compare the deep wound infection rates in patients undergoing spinal surgery with the application of topical intrawound vancomycin powder (TIVP) in the surgical site in addition to standard systemic prophylaxis with those in a matched historical cohort of patients for whom TIVP was not used.

OVERVIEW OF LITERATURE

Surgical site infection (SSI) after spine surgery is debilitating and is responsible for a significant increase in the health care costs, hospital stay, and morbidities. Although the application of TIVP before surgical closure is a promising method for reducing the SSI rate after spine surgery, its use is controversial, and currently, research trials are focusing on identifying its safety, efficacy, and the potential patient population.

METHODS

A group of 88 patients who underwent posterior spinal surgery with TIVP administration (treatment group) was compared to a historical control group of 70 patients who had received only standard systemic intravenous prophylaxis (control group) for the analysis of deep SSI rate and the involved organisms.

RESULTS

The overall rate of deep SSIs was 2.5% (4/158). All the SSIs were observed in patients who had posterior instrumentation and fusion for ≥3 levels. In the treatment group, the SSI rate was 3.4% (3/88), and the bacteria isolated were Escherichia coli (n=2) and Pseudomonas aeruginosa (n=1). In the control group, the infection rate was 1.4% (1/70), and the isolated bacteria were Morganella morganii and Staphylococcus epidermidis. No statistically significant association was found between the SSI rates of the treatment and control groups.

CONCLUSIONS

Although the difference in the SSI rates was not statistically significant, the present results suggest that TIVP administration could not reduce the risk of deep SSIs after spinal surgery. Moreover, TIVP administration might also affect the underlying pathogens by increasing the propensity for gram-negative species.

Meta-analysis of topical vancomycin powder for microbial profile in spinal surgical site infections

OBJECTIVES

To systematically evaluate the impact of topical vancomycin powder for microbial profile in spinal surgical site infections.

METHODS

All available literature regarding the topical use of vancomycin powder to prevent postoperative spinal infections was retrieved from the MEDLINE, EMBASE, and Cochrane databases starting from the creation date and up until September 30, 2018.

RESULTS

A total of 21 studies involving 15,548 patients were reviewed. The combined odds ratio showed that topical use of vancomycin powder was effective for reducing the incidence of gram-positive bacterial infections in spinal surgical sites (OR 0.41, P < 0.00001) without affecting its efficacy in the prevention of polymicrobial infections (OR 0.30, P = 0.03). Additionally, it could significantly reduce the infection rate of methicillin-resistant staphylococcus (OR 0.34, P < 0.0001). However, topical vancomycin powder showed no advantage for preventing gram-negative bacterial infections (OR 0.94, P = 0.75).

CONCLUSIONS

Topical administration of vancomycin powder may not increase the rates of gram-negative bacterial or polymicrobial infections in spinal surgical sites. On the contrary, it can significantly reduce the infection rates of gram-positive bacteria, methicillin-resistant staphylococcus (MRS) and microorganism. Of course, the topical vancomycin powder cannot change the rates of gram-negative bacterial infections, which may be related to the antimicrobial spectrum of vancomycin. Due to the limited number of articles included in this study, additional large-scale and high-quality studies are needed to provide more reliable clinical evidence.

Local Application of Vancomycin in Spine Surgery Does Not Result in Increased Vancomycin-Resistant Bacteria-10-Year Data

STUDY DESIGN

Case-control study.

OBJECTIVES

To analyze the microbial flora in surgical spine infections and their antibiotic resistance patterns across time and determine the correlation between vancomycin application in the wound and vancomycin-resistant microbes.

SUMMARY OF BACKGROUND DATA

Prior studies show a reduction in surgical site infections with intrawound vancomycin placement. No data are available on the potential negative effects of this intervention, in particular, whether there would be a resultant increase in vancomycin-resistant organisms or bacterial resistance profiles.

METHODS

All culture-positive surgical site infections at a single institution were analyzed from 2007 to 2017. Each bacterium was assessed independently for resistance patterns. The two-tailed Fisher exact test was used to determine the correlation between vancomycin application and the presence of vancomycin-resistant bacteria, polymicrobial infections, or gram-negative bacterial infections.

RESULTS

One hundred and eight bacteria were isolated from 113 surgical site infections from 2007 to 2017. The most common organisms were staphylococcus with varying resistance patterns and Escherichia coli. Vancomycin-resistant Enterococcus faecium was isolated in three infections. Out of the 4,878 surgical cases from 2011 to 2017, vancomycin was placed in 48.3%, and no vancomycin in 51.7%. There were 33 infections (1.4%) in the vancomycin group and 20 infections (0.8%) in the no-vancomycin group (χ² = 0.0521). There was no correlation between vancomycin application in the wound and vancomycin-resistant microbes (χ² = 0.2334) and polymicrobial infections (χ² = 0.1328). There was an increased rate of gram-negative organisms in infections after vancomycin application in the wound versus no vancomycin (χ² = 0.0254).

CONCLUSIONS

Topical vancomycin within the surgical site is not correlated with vancomycin-resistant bacteria. However, there was an increased incidence of gram-negative organisms in infections after vancomycin application in the wound versus no vancomycin. Continued surveillance with prospectively collected randomized data is necessary to better understand bacterial evolution against current antimicrobial techniques.

LEVEL OF EVIDENCE

Level III.

Selection pressures of vancomycin powder use in spine surgery: a meta-analysis

BACKGROUND CONTEXT

Surgical site infection (SSI) is a serious and costly complication of spine surgery. Many surgeons apply vancomycin powder to the surgical wound to prevent SSIs. While multiple studies have reported reduced rates of SSI, others have suggested that widespread use of intrawound vancomycin may increase the incidence of vancomycin-resistant, gram-negative, or polymicrobial spinal infections.

PURPOSE

To systematically review the current literature on vancomycin powder in spine surgery and its impact on SSI culture profiles.

STUDY DESIGN

Meta-analysis.

SAMPLE

We included observational studies, retrospective chart reviews, and randomized controlled trials of patients who underwent spine surgeries with and without vancomycin powder application to surgical wounds and reported SSI rates.

OUTCOME MEASURES

The primary outcome was postoperative SSIs. Subgroup analyses compared rates of postoperative SSIs.

METHODS

We performed a comprehensive search of numerous electronic databases and conference proceedings pertaining to this topic. Our meta-analysis was conducted according to Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Inclusion criteria consisted of spine surgeries with or without use of vancomycin powder, case-control design, sample sizes of at least 10 in each arm, SSIs identified with bacterial cultures, and follow-up of at least 1 month. Data extracted from eligible studies included, but was not limited to, SSI rates, cultured organisms, and vancomycin powder dose. Chi-square analyses were used to assess pooled risk-estimates of intrawound vancomycin powder on reducing SSIs and selecting for gram-negative and/or polymicrobial organisms compared to controls. Pooled odds ratios, relative risks, and relative risk increase for observed outcomes were calculated. A meta-analysis was then performed with a forest plot to determine risk estimates' heterogeneity with I² index, Q-statistic, and p value under a fixed-effects model. Funnel plot was used to assess publication bias. None of the authors received funding or other support for this review.

RESULTS

After reviewing nearly 400 titles and abstracts, 28 articles met inclusion criteria. They included two randomized controlled trials, one observational study, and 25 retrospective analyses. There were 412 cases of SSI (3.8%) in the control group (N=10,846) compared to 197 SSIs (2.3%) in the vancomycin powder group (N=8,456). The pooled odds ratio was 0.60 (95% confidence intervalCI 0.51-0.71, p<.05). The rate of gram-positive SSI was significantly higher in the control group compared to the vancomycin group (70% vs. 45.1%, p<.05). The rate of gram-negative and polymicrobial SSI was significantly higher in the vancomycin group (35.8% vs. 18.5%, p<.05). The risk of developing a gram-negative or polymicrobial SSI was nearly twice (93.5% higher) in the vancomycin group. Study heterogeneity and synthesizing mostly retrospective data were primary limitations.

CONCLUSIONS

Widespread use of prophylactic intrawound vancomycin may increase the incidence of gram-negative and polymicrobial SSIs. Vancomycin powder should likely be restricted to procedures and patients most at risk for infection.

A double-blind randomized controlled trial of the local application of vancomycin versus ampicillin powder into the operative field for thoracic and/or lumbar fusions

OBJECTIVERetrospective studies have reported that the local application of vancomycin (VCM) powder into the operative field decreases the incidence of surgical site infection (SSI) in thoracic and/or lumbar fusion. Authors of the present study prospectively evaluated the effects of VCM in patients undergoing thoracic and/or lumbar fusion.METHODSIn this randomized double-blind trial, 230 patients undergoing thoracic and/or lumbar fusion were randomly assigned to the local administration of VCM (interventional group, 1 g) or ampicillin (AMP; control group, 1 g) into the surgical field. The primary outcome was SSI results within 1 year of surgery.RESULTSThe trial was prematurely stopped according to predetermined rules. The results showed one superficial infection (0.9%, Staphylococcus aureus) and one deep infection (0.9%, S. aureus) in the VCM group and two superficial infections (1.8%, Staphylococcus epidermidis and culture negative) and one deep infection (0.9%, methicillin-resistant S. aureus) in the AMP group. No significant differences in infection rates were observed between the groups (p = 0.8).CONCLUSIONSThis double-blind randomized controlled trial demonstrated that the local application of VCM or AMP powder into the operative field in short thoracic and/or lumbar fusion procedures resulted in a similar incidence of SSI.■ CLASSIFICATION OF EVIDENCE Type of question: therapeutic; study design: randomized controlled trial; evidence: class III.Clinical trial registration no.: UMIN000009377 (umin.ac.jp/ctr).

Effect of intrawound vancomycin application in spinal surgery on the incidence of surgical site infection: a meta-analysis

Background

Despite great advances in aseptic surgical techniques, surgical site infection (SSI) is still one of the main complications after spine surgery. SSI can bring tremendous physical, psychological, and economic challenges to patients. Intrawound vancomycin application is a much disputed method for the prevention of SSI after spine surgery.

Objective

The aim of this study is to review the current literature for studies on the intra-wound application of vancomycin powder and to analyze its effectiveness in the prevention of postoperative SSI.

Methods

PubMed, Medline, Elsevier, and CNKI were searched for the key words “vancomycin”, “local/intraoperative/topical/intra-wound”, “spine/spinal/lumbar/cervical/thoracolumbar surgery”, “infection”, and “SSI” in published studies on the effectiveness of intrawound vancomycin application to prevent postoperative SSI. RevMan 5.3 was used to compare the data extracted from the studies included.

Results

A total of 27 studies involving 17,321 patients were included in the final analysis. Among those patients, 7,423 patients were treated with vancomycin to prevent SSI, with 9,898 in control groups. SSI incidence after surgery in experimental groups was 0.39 times as high as control groups, and this difference was statistically significant (P<0.01). Among patients who underwent internal fixation, vancomycin application significantly reduced the incidence of postoperative SSI (OR 0.31 95% CI 0.19–0.50; P<0.01). Meanwhile, vancomycin did not affect SSI incidence in patients who did not receive internal fixation (P=0.17) or received deformity correction (P=0.25).

Conclusion

SSI incidence after spinal surgery can be significantly reduced by intrawound application of vancomycin in most circumstances. This method can be applied in various spinal procedures involving instrumentation to prevent postoperative SSI.

Use of Intrawound Antibiotics in Orthopaedic Surgery

Intrawound antibiotics have been used in orthopaedic surgery procedures to prevent the development of surgical site infections. Local delivery of antibiotic powder has demonstrated a notable reduction in surgical site infection in rabbit and rodent in vivo models, as well as in other surgical fields, including vascular, colorectal, cardiothoracic, and dermatologic surgery. Intrawound antibiotic powder has been used in many orthopaedic applications, including spine surgery, total joint arthroplasty, trauma, foot and ankle reconstruction, and elbow surgery. Although the theory behind the use of intrawound antibiotic powder is promising, it has potential adverse effects, including antibiotic resistance, circulatory collapse, and decreased bone healing. In addition, most studies in the orthopaedic literature on the use of intrawound antibiotic powder are retrospective in nature.

Effect of Intra-wound Vancomycin for Spinal Surgery: A Systematic Review and Meta-analysis

Intra-site prophylactic vancomycin in spine surgery is an effective method of decreasing the incidence of postsurgical wound infection. However, there are differences in the prophylactic programs used for various spinal surgeries. Thus, this systematic review and meta-analysis aimed to evaluate the effectiveness of using intra-wound vancomycin during spinal surgery and to explore the effects of dose-dependence and the method of administration in a subgroup analysis. A total of 628 citations or studies were searched in PubMed, Ovid, Web of Science, and Google Scholar that were published before August 2016 with the terms "local vancomycin", "intra-wound vancomycin", "intraoperative vancomycin", "intra-site vancomycin", "topical vancomycin", "spine surgery", and "spinal surgery". Finally, 19 retrospective cohort studies and one prospective case study were eligible for inclusion in the systematic review and meta-analysis. The odds of developing postsurgical wound infection without prophylactic local vancomycin use were 2.83-fold higher than the odds of experiencing wound infection with the use of intra-wound vancomycin (95% confidence interval, 2.03-3.95; P = 0.083; I² = 32.2%). The subgroup analysis including the dosage and the method of administration, revealed different results compared to previous research. The value of I² in the 1-g group was 27.2%, which was much lower than in the 2-g group (I² = 57.6%). At the same time, the value of I² was 0.0% (P = 0.792, OR = 2.70) when vancomycin powder was directly sprinkled into all layers of the wound. However, there is high heterogenicity (I² = 60.0%, P = 0.007, OR = 2.83) when vancomycin powder is not exposed to the bone graft and instrumentation. There are differences found with the method of local application of vancomycin for reducing postoperative wounds and further studies are necessary, including investigations focusing on the dose-dependent effects during spinal or the topical pharmacokinetic and other orthopaedic surgeries.

Implementation of an infection prevention bundle and increased physician awareness improves surgical outcomes and reduces costs associated with spine surgery

OBJECTIVE

Previous studies have demonstrated the efficacy of infection prevention protocols in reducing infection rates. This study investigated the effects of the development and implementation of an infection prevention protocol that was augmented by increased physician awareness of spinal fusion surgical site infection (SSI) rates and resultant cost savings.

METHODS

A cohort clinical investigation over a 10-year period was performed at a single tertiary spine care academic institution. Preoperative infection control measures (chlorohexidine gluconate bathing, Staphylococcus aureus nasal screening and decolonization) followed by postoperative infection control measures (surgical dressing care) were implemented. After the implementation of these infection control measures, an awareness intervention was instituted in which all attending and resident neurosurgeons were informed of their individual, independently adjudicated spinal fusion surgery infection rates and rankings among their peers. During the course of these interventions, the overall infection rate was tracked as well as the rates for those neurosurgeons who complied with the preoperative and postoperative infection control measures (protocol group) and those who did not (control group).

RESULTS

With the implementation of postoperative surgical dressing infection control measures and physician awareness, the postoperative spine surgery infection rate decreased by 45% from 3.8% to 2.1% (risk ratio 0.55; 95% CI 0.32–0.93; p = 0.03) for those in the protocol cohort, resulting in an estimated annual cost savings of $291,000. This reduction in infection rate was not observed for neurosurgeons in the control group, although the overall infection rate among all neurosurgeons decreased by 54% from 3.3% to 1.5% (risk ratio 0.46; 95% CI 0.28–0.73; p = 0.0013).

CONCLUSIONS

A novel paradigm for spine surgery infection control combined with physician awareness methods resulted in significantly decreased SSI rates and an associated cost reduction. Thus, information sharing and physician engagement as a supplement to formal infection control measures result in improvements in surgical outcomes and costs.

Reduction in surgical site infection with suprafascial intrawound application of vancomycin powder in instrumented posterior spinal fusion: a retrospective case-control study

OBJECTIVE Recent studies have demonstrated the efficacy of subfascial intrawound application of vancomycin powder in spine surgery in reducing the rate of surgical site infections (SSIs). However, to date no study has evaluated the efficacy and safety of suprafascial application of vancomycin powder in spine surgery. The purpose of this study was to quantify the rate of SSIs after open instrumented posterior spinal fusion with and without application of suprafascial vancomycin powder and to evaluate the rate of vancomycin powder-related local adverse effects. METHODS The authors conducted a single-center retrospective case-control study of adult patients undergoing open instrumented posterior fusion of the cervical, thoracic, or lumbar spine performed by a single surgeon from January 2010 through December 2016. In March 2013, routine application of 1 g of suprafascial vancomycin powder was started for all cases in addition to standard systemic antibiotic prophylaxis. Baseline demographics and operative data as well as the SSI rates were compared between the study groups. The incidence of vancomycin powder-related adverse effects was analyzed. RESULTS A total of 515 patients (268 in the untreated group and 247 in the treated group) were included in the study. The mean age was significantly higher in the treated group than in the untreated group (58.4 vs 54.4 years, p < 0.01). Operative variables were similar between the study groups. Patients receiving vancomycin powder had a significantly lower infection rate (5.6% in the untreated group vs 0% in the treated group, p < 0.001). No vancomycin powder-related adverse effects were identified in the treated group. CONCLUSIONS Routine application of suprafascial intrawound vancomycin powder in addition to systemic antibiotic prophylaxis is an easy-to-use, safe, and effective strategy for preventing SSIs after instrumented posterior spinal fusion. Suprafascial application of vancomycin powder could be a valuable alternative to previously reported subfascial distribution, minimizing the risk of local adverse drug reactions.

Do Dose-Dependent Microbial Changes Occur during Spine Surgery as a Result of Applying Intrawound Vancomycin Powder?: A Systematic Literature Review

We analyzed dose-dependent effects of vancomycin on wound infection bacteria and investigated the relationship between dose and microbial imbalances in patients treated with intrawound vancomycin powder during spine surgery. Numerous trials have confirmed that using intrawound vancomycin powder during spine surgery may decrease postoperative wound infection rates. However, potential risks include changes in wound infection bacteria, inhibition of bone fusion, and systemic toxicity. We searched PubMed for articles published since October 2016 with the following terms: “local vancomycin” or “intrawound vancomycin” or “intraoperative vancomycin” or “intrawound vancomycin” or “topical vancomycin” and “spinal surgery” or “spine surgery.” We also screened the reference lists of included articles for additional studies and extracted data related to dose, infecting bacteria, sample size, infection rate and types, location of spine surgery, and perioperative antibiotics used. Our review includes one prospective and nine retrospective studies. Overall, 1 or 2 g local vancomycin powder was used in 2,394 patients. Gram-negative bacteria were dominant in patients in whom 1 g vancomycin powder was used, whereas gram-positive bacteria were dominant in those in whom 2 g powder was used. The exact mechanism underlying this dose-dependent trend remains unclear, although it may be attributed to the pharmacological characteristics of vancomycin. The included studies showed that trends in infection bacteria may change after the use of topical vancomycin powder. In addition, the observed increase in gram-negative bacteria when intrawound vancomycin powder is used has generated considerable attention. The present results differ from previous results but do not provide additional information regarding vancomycin dose and microbial changes in infected wounds. Additional large randomized controlled trials are needed to determine the relationship between vancomycin dose and the types of wound infection bacteria in patients treated with intrawound vancomycin powder during spine surgery.

Use of intrawound vancomycin powder against postoperative infection after spine surgery

Local application of vancomycin has recently become widely used in spine surgery. However, local application is not included in the indication and has not been approved by the US Food and Drug Administration (FDA). Thus, we searched for reports with "intra wound-vancomycin" and "SSI" as keywords in the MEDLINE database, and investigated the efficacy, problems with use, and future prospects based on these reports. Intrawound vancomycin was described as effective in most of the reports, but was found to have no effect or to aggravate the condition in some reports. A toxic effect on osteoblasts due to a high local concentration was described in some reports, whereas local application was found to be safe in other studies. The amount of vancomycin used and the administration method varied among the reports. Overall, the results suggest that intrawound vancomycin is clinically effective, but this has yet to be established in a randomized controlled trial. There is a need to identify cases that should be selected for this treatment and to investigate the dose and optimum concentration of vancomycin for clinical use.

Intrawound application of vancomycin changes the responsible germ in elective spine surgery without significant effect on the rate of infection: a randomized prospective study

PURPOSE

Surgical site infection (SSI) is a costly complication associated with spine surgery. The impact of intrawound vancomycin has not been strongly postulated to decrease the risk of surgical site infection. We designed study to determine whether intrawound vancomycin application reduces the risk of SSI in patients after spine surgery.

METHODS

A prospective randomized control trial study to evaluate the patients with elective spine surgery in a period of 15 month was designed. Patients were divided into two groups based on whether intrawound vancomycin was applied or not. The relative risk of SSI within postoperative 30 days was evaluated.

RESULTS

Three hundred and eighty patients were included in this study: degenerative spine pathologies and tumor 80% (304), trauma 11% (42) and deformity 9% (34). Intrawound vancomycin was used in 51% of patients. Prevalence of SSI was 2.7% in the absence of vancomycin use versus 5.2% with intrawound vancomycin. In multivariable regression model, those with higher number of levels exposed, postoperative ICU admission and obesity and use of instrumentation more than two levels had higher risk of developing SSI. In the treatment group Acinetobacter and Pseudomonas aeruginosa (20%) were the most common pathogens. In control group, Staphylococcus aureus and Acinetobacter (40%) were the most common organisms.

CONCLUSIONS

Intrawound application of vancomycin after elective spine surgery was not associated with reduced risk of SSI and return to OR associated with SSI in our patients. However, the use of intrawound vancomycin changed the responsible infection germ.

Local Intra-wound Administration of Powdered Antibiotics in Orthopaedic Surgery

Surgical site infection (SSI) is one of the most common complications after orthopaedic surgery, leading to significant morbidity and its associated costs. Surgical guidelines strongly recommend the use of systemic antibiotic prophylaxis to reduce the risk for developing SSI. Locally administered powdered antibiotics have the potential to provide remarkably high intra-wound concentrations without risk for systemic toxicity. However, a paucity of high quality evidence in the orthopaedic literature has prevented widespread adoption of this technique. The majority of clinical studies on local intra-wound antibiotics have evaluated the use of topical powdered vancomycin in spinal surgery, though only a single prospective study currently exists. This review will discuss all the available evidence describing the effectiveness, pharmacokinetics, and potential adverse effects with the use of topical powdered antibiotics in orthopedic surgery.

Time-Dependent Effectiveness of Locally Applied Vancomycin Powder in a Contaminated Traumatic Orthopaedic Wound Model

OBJECTIVES

To evaluate the effectiveness of locally applied vancomycin powder at different times postinfection in a contaminated traumatic animal model.

METHODS

This study used an established segmental defect rat femur model contaminated with Staphylococcus aureus UAMS-1 followed by treatment at 6 or 24 hours postinfection. Three treatments were evaluated: debridement and irrigation alone (control group) or in combination with either vancomycin powder or vancomycin-impregnated poly(methyl methacrylate) beads. Serum vancomycin levels were determined at scheduled time points over 14 days; bone, surrounding muscle, and implants were harvested for bacterial and inflammatory analyses.

RESULTS

Locally applied vancomycin powder and impregnated beads significantly reduced bacteria both within the bone and implant when treatment was performed at 6 hours. Delaying treatment to 24 hours significantly reduced the therapeutic efficacy of locally applied vancomycin of both groups. Serum vancomycin levels were detectable in all animals treated with vancomycin powder at 24 hours, but absorption was negligible from beads. At 14 days, vancomycin was detectable in the surrounding musculature of all animals and in serum of 20% of animals treated with vancomycin powder.

CONCLUSIONS

This study suggests that vancomycin powder is a promising adjunctive therapy for preventing infection in traumatic wounds when treatment is performed early. This time-dependent effectiveness of vancomycin powder is similar to that observed with systemic and other local delivery adjuncts, which is likely attributable to biofilm formation after contamination, conferring intrinsic recalcitrance to antimicrobials.

Evaluation of antimicrobial prophylaxis against postoperative infection after spine surgery: Limit of the first generation cephem

In our department, first-generation cephem (CEZ) are generally administered for 2 days as antimicrobial prophylaxis (AMP) for spinal surgery. However, the incidence of surgical site infection (SSI) has recently increased, particularly cases involving coagulase-negative Staphylococci (CNS) as an etiologic agent. The objective was to elucidate the problems with the current AMP and the risk factors of SSI through a retrospective investigation of affected cases. The subjects were patients who underwent spine surgery at our department between August 2007 and June 2013. The subjects were divided into those who developed SSI (S group) and who did not develop SSI (non-SSI (N) group), patients who developed CNS infection in the S group was subdivided as C group, and the risk factors were investigated. The significance of each factor was analyzed using cross tabulation, and multivariate logistic regression analyses were performed with 22 of the investigation factors as explanatory variables. The incidence of SSI was 2.55%, and the etiologic agent was CNS in 17 patients. Upon comparison between the S and N groups, the presence of 3 or more underlying diseases and blood loss were extracted as significant risk factors. Upon comparison between the C and N groups, emergency surgery and intra- and postoperative steroid administration were extracted as significant risk factors, in addition to the presence of 3 or more underlying diseases and blood loss. The effect of the current AMP using first generation cephem is limited, and reconsideration of the protocol may be necessary.