Glycopeptides Versus β-Lactams for the Prevention of Surgical Site Infections in Cardiovascular and Orthopedic Surgery: A Meta-Analysis

WHO's essential medicines and AWaRe: recommendations on first- and second-choice antibiotics for empiric treatment of clinical infections

The WHO Model List of Essential Medicines (EML) prioritizes medicines that have significant global public health value. The EML can also deliver important messages on appropriate medicine use. Since 2017, in response to the growing challenge of antimicrobial resistance, antibiotics on the EML have been reviewed and categorized into three groups: Access, Watch, and Reserve, leading to a new categorization called AWaRe. These categories were developed taking into account the impact of different antibiotics and classes on antimicrobial resistance and the implications for their appropriate use. The 2023 AWaRe classification provides empirical guidance on 41 essential antibiotics for over 30 clinical infections targeting both the primary health care and hospital facility setting. A further 257 antibiotics not included on the EML have been allocated an AWaRe group for stewardship and monitoring purposes. This article describes the development of AWaRe, focussing on the clinical evidence base that guided the selection of Access, Watch, or Reserve antibiotics as first and second choices for each infection. The overarching objective was to offer a tool for optimizing the quality of global antibiotic prescribing and reduce inappropriate use by encouraging the use of Access antibiotics (or no antibiotics) where appropriate. This clinical evidence evaluation and subsequent EML recommendations are the basis for the AWaRe antibiotic book and related smartphone applications. By providing guidance on antibiotic prioritization, AWaRe aims to facilitate the revision of national lists of essential medicines, update national prescribing guidelines, and supervise antibiotic use. Adherence to AWaRe would extend the effectiveness of current antibiotics while helping countries expand access to these life-saving medicines for the benefit of current and future patients, health professionals, and the environment.

Role of targeted and universal mupirocin-based decolonization for preventing surgical-site infections in patients undergoing cardiothoracic surgery: A systematic review and meta-analysis

The purpose of the present study was to provide a systematic literature review and pool evidence on the efficacy of mupirocin-based decolonization protocol in reducing surgical-site infections (SSIs) in patients undergoing cardiothoracic (CT) surgery based on their Staphylococcus (S.) aureus carrier state. The PubMed, Embase, Ovid, BioMed Central, Cochrane Central Register of Controlled Trials and Google Scholar databases were searched for studies comparing mupirocin-based decolonization with controls for reducing SSIs in patients following CT surgery. Studies were grouped based on the targeted population of intervention, i.e. carriers or all patients. A total of 17 studies were included. Of these, 8 studies used targeted mupirocin-based decolonization, while universal decolonization was performed in 9 studies. The results were conflicting for studies performing targeted decolonization and it was not possible to perform a meta-analysis due to non-homogenous studies. Pooled analysis of 34,859 patients indicated that universal mupirocin-based decolonization significantly reduced the risk of all SSIs [risk ratio (RR): 0.54; 95% CI: 0.40,0.75; I²=73.35%]. The intervention significantly reduced the risk of superficial SSIs (RR: 0.37; 95% CI: 0.25,0.55; I²=0%) but not of deep SSIs (RR: 0.45; 95% CI: 0.19,1.09; I²=80.67%). The results indicated a significantly reduced risk of S. aureus SSIs (SA-SSIs) with mupirocin-based decolonization (RR: 0.44; 95% CI: 0.32,0.61; I²=0%) but not for methicillin-resistant S. aureus (MRSA-SSIs; RR: 0.25; 95% CI: 0.05,1.28; I²=79.07%). Evidence on the role of targeted mupirocin-based decolonization to reduce SSIs after CT surgery was non-coherent and inconclusive. Analysis of low-quality retrospective studies suggested that universal mupirocin-based decolonization may reduce all SSIs, superficial SSIs and SA-SSIs, but not deep SSIs or MRSA-SSIs in patients after CT surgery.

Treatment with Ceftriaxone in Complicated Diverticulitis Increases the Incidence of Intra-Abdominal Enterococcus faecium Detection

Background: Complicated diverticulitis of the sigmoid colon typically is treated by resection after initial antibiotic treatment. Third-generation cephalosporins are the drugs of choice but are not effective against enterococci and can induce colonic colonization by Enterococcus faecium within hours. Infections caused by enterococci, especially E. faecium, are difficult to treat but should be considered in the strategic treatment planning of hospital-acquired peritonitis (e.g., anastomotic leakage), especially in immunocompromised patients. Methods: To determine whether the duration of pre-operative ceftriaxone treatment in complicated diverticulitis increases the incidence of intra-abdominal E. faecium detection, we analyzed all patients operated on for diverticulitis of the sigmoid colon in our department between 2008 and 2016. Results: Analyzing 516 resections performed for complicated diverticulitis, we found that E. faecium generally was detected intra-abdominally more often in the group that underwent longer pre-operative ceftriaxone treatment (≥ 4 days). During primary resection, E. faecium was detected in 2.7%, 11.1%, and 37.0% cases in the group undergoing immediate operation, 1-3 days of antibiotic treatment, and ≥4 days of antibiotic treatment, respectively. Enterococcus faecium was detected in 0, 25.0%, and 70.6% of surgical revisions and 28.6%, 14.3%, and 56.0%, respectively, of incisional surgical site infections with identified pathogens. A multivariable analysis discovered anastomotic leakage and antibiotic treatment lasting ≥4 days to be independent risk factors for intra-abdominal isolation of E. faecium. Conclusion: A ceftriaxone treatment ≥4 days led to a higher incidence of intra-abdominal E. faecium. Our data further suggested that empiric coverage of E. faecium in the treatment of hospital-acquired peritonitis could be beneficial after a long duration of ceftriaxone treatment.

[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.

Adding vancomycin to perioperative prophylaxis decreases deep sternal wound infections in high-risk cardiac surgery patients

OBJECTIVES

Perioperative prophylaxis with cephalosporins reduces sternal wound infections (SWIs) after cardiac surgery. However, more than 50% of coagulase-negative staphylococci, an important pathogen, are cephalosporin resistant. The aim of this study was to determine the impact of adjunctive vancomycin on SWIs in high-risk patients.

METHODS

We conducted a pre- and postintervention study in an academic hospital. Preintervention (2010-2011), all patients received prophylaxis with 1.5 g of cefuroxime for 48 h. During the intervention period (2012-2013), high-risk patients additionally received 1 g of vancomycin. High-risk status was defined as body mass index ≤18 or ≥ 30 kg/m2, reoperation, renal failure, diabetes mellitus, chronic obstructive pulmonary disease or immunosuppressive medication. Time series analysis was performed to study SWI trends and logistic regression to determine the effect of adding vancomycin adjusting for high-risk status.

RESULTS

A total of 3902 consecutive patients (n = 1915 preintervention and n = 1987 postintervention) were included, of which 1493 (38%) patients were high-risk patients. In the high-risk group, 61 of 711 (8.6%) patients had SWI before and 30 of 782 (3.8%) patients after the intervention. Focusing on deep SWI (DSWI), 33 of 711 (4.6%) patients had DSWI before and 13 of 782 (1.7%) patients afterwards; the absolute risk difference of 2.9% yielded a number-needed-to-treat of 34 to prevent 1 DSWI. Corrected for high-risk status, adding vancomycin significantly reduced the overall SWI rate (odds ratio 0.42, 95% confidence interval 0.26-0.67; P < 0.001) and the subset of DSWI (odds ratio 0.30, 95% confidence interval 0.14-0.62; P = 0.001). The rate of SWI in low-risk patients remained unchanged.

CONCLUSIONS

Adding vancomycin to standard antibiotic prophylaxis in high-risk patients significantly reduced DSWI after cardiac surgery.

Multicentre randomised double-blind placebo controlled trial of combination vancomycin and cefazolin surgical antibiotic prophylaxis: the Australian surgical antibiotic prophylaxis (ASAP) trial

INTRODUCTION

Resistant Gram-positive organisms, such as methicillin-resistant staphylococci, account for a significant proportion of infections following joint replacement surgery. Current surgical antimicrobial prophylaxis guidelines recommend the use of first-generation or second-generation cephalosporin antibiotics, such as cefazolin. Cefazolin, however, does not prevent infections due to these resistant organisms; therefore, new prevention strategies need to be examined. One proposed strategy is to combine a glycopeptide antibiotic with cefazolin for prophylaxis. The clinical benefit and cost-effectiveness of this combination therapy compared with usual therapy, however, have not been established.

METHODS AND ANALYSIS

This randomised, double-blind, parallel, superiority, placebo-controlled, phase 4 trial will compare the incidence of all surgical site infections (SSIs) including superficial, deep and organ/space (prosthetic joint) infections, safety and cost-effectiveness of surgical prophylaxis with cefazolin plus vancomycin to that with cefazolin plus placebo. The study will be performed in patients undergoing joint replacement surgery. In the microbiological sub-studies, we will examine the incidence of SSIs in participants with preoperative staphylococci colonisation (Sub-Study 1) and incidence of VRE acquisition (Sub-Study 2). The trial will recruit 4450 participants over a 4-year period across 13 orthopaedic centres in Australia. The primary outcome is the incidence of SSI at 90 days post index surgery. Secondary outcomes include the incidence of SSI according to joint and microorganism and other healthcare associated infections. Safety endpoints include the incidence of acute kidney injury, hypersensitivity reactions and all-cause mortality. The primary and secondary analysis will be a modified intention-to-treat analysis consisting of all randomised participants who undergo eligible surgery. We will also perform a per-protocol analysis.

ETHICS AND DISSEMINATION

The study protocol was reviewed and approved by The Alfred Hospital Human Research Ethics Committee (HREC/18/Alfred/102) on 9 July 2018. Study findings will be disseminated in the printed media, and learnt forums.

TRIAL REGISTRATION NUMBER

ACTRN12618000642280.

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.

[Spectrum of pathogens in postoperative complications of visceral surgery : The problem of multidrug resistance]

In general surgery the etiology of surgical site infections has not significantly changed over the last 30 years. Gram-positive bacteria, e.g. coagulase negative staphylococci (CNS), Staphylococcus aureus and Enterococcus spp. as well as Gram-negative bacteria, e.g. Escherichia coli, Enterobacter spp., Klebsiella spp. and Pseudomonas aeruginosa, are the most common findings. Although in general surgery 10% of the S. aureus causing postoperative wound infections were methicillin resistant (MRSA), no cases of multidrug-resistant Gram-negative (MRGN) bacteria were reported. Yeasts (particularly Candida spp.) are rarely the pathogen causing surgical site infections (≤3%) and concomitant risk factors are typical (e.g. diabetes, chemotherapy, immunosuppression and malnutrition). Viruses are rarely the cause of surgical site infections. Transmission can occur by HBV, HCV or HIV positive surgical staff or in organ transplantations and postoperative reactivation of persistent infections is possible (especially for HBV, HCV, CMV, EBV and HIV). The principles for prevention of surgical site infections are dealt with as consequences of preoperative colonization by MRSA, methicillin-sensitive S. aureus (MSSA) and MRGN and reviewed with respect to screening, perioperative antibiotic prophylaxis and decolonization. In nosocomial peritonitis, the selection of antibiotics should consider previous antibiotic treatment. A single intra-abdominal detection of Candida spp. usually does not require antimycotic treatment in postoperatively stable and immunocompetent patients but is recommended in severe community-acquired or nosocomial peritonitis. Viral infections can be avoided by screening of organ donors and serological surveillance of surgery personnel.

Review of MRSA screening and antibiotics prophylaxis in orthopaedic trauma patients; The risk of surgical site infection with inadequate antibiotic prophylaxis in patients colonized with MRSA

AIMS

The primary aim of this study was to determine whether orthopaedic trauma patients receive appropriate antibiotic prophylaxis keeping in view the results of their MRSA screening. The secondary aim was to analyse the risk of developing MRSA surgical site infection with and without appropriate antibiotic prophylaxis in those colonized with MRSA.

PATIENTS AND METHODS

We reviewed 400 consecutive orthopaedic trauma patient episodes. Preoperative MRSA screening results, operative procedures, prophylactic antibiotics and postoperative course were explored. In addition to these consecutive patients, the hospital MRSA database over the previous 5 years identified 27 MRSA colonized acute trauma patients requiring surgery.

RESULTS

Of the 400 consecutive patient episodes, 395(98.7%) had MRSA screening performed on admission. However, in 236 (59.0%) cases, the results were not available before the surgery. Seven patient episodes (1.8%) had positive MRSA colonization. Analysis of 27 MRSA colonized patients revealed that 20(74%) patients did not have the screening results available before the surgery. Only 5(18.5%) received Teicoplanin and 22(81.4%) received cefuroxime for antibiotic prophylaxis before their surgery. Of those receiving cefuroxime, five (22.73%) patients developed postoperative MRSA surgical site infection (SSI) but none of those (0%) receiving Teicoplanin had MRSA SSI. The absolute risk reduction for SSI with Teicoplanin as antibiotic prophylaxis was 22.73% (CI=5.22%-40.24%) and NNT (Number Needed to Treat) was 5 (CI=2.5-19.2) CONCLUSION: Lack of available screening results before the surgery may lead to inadequate antibiotic prophylaxis increasing the risk of MRSA surgical site infection. Glycopeptide (e.g.Teicoplanin) prophylaxis should be considered when there is history of MRSA colonization or MRSA screening results are not available before the surgery.

Potential burden of antibiotic resistance on surgery and cancer chemotherapy antibiotic prophylaxis in the USA: a literature review and modelling study

BACKGROUND

The declining efficacy of existing antibiotics potentially jeopardises outcomes in patients undergoing medical procedures. We investigated the potential consequences of increases in antibiotic resistance on the ten most common surgical procedures and immunosuppressing cancer chemotherapies that rely on antibiotic prophylaxis in the USA.

METHODS

We searched the published scientific literature and identified meta-analyses and reviews of randomised controlled trials or quasi-randomised controlled trials (allocation done on the basis of a pseudo-random sequence-eg, odd/even hospital number or date of birth, alternation) to estimate the efficacy of antibiotic prophylaxis in preventing infections and infection-related deaths after surgical procedures and immunosuppressing cancer chemotherapy. We varied the identified effect sizes under different scenarios of reduction in the efficacy of antibiotic prophylaxis (10%, 30%, 70%, and 100% reductions) and estimated the additional number of infections and infection-related deaths per year in the USA for each scenario. We estimated the percentage of pathogens causing infections after these procedures that are resistant to standard prophylactic antibiotics in the USA.

FINDINGS

We estimate that between 38·7% and 50·9% of pathogens causing surgical site infections and 26·8% of pathogens causing infections after chemotherapy are resistant to standard prophylactic antibiotics in the USA. A 30% reduction in the efficacy of antibiotic prophylaxis for these procedures would result in 120,000 additional surgical site infections and infections after chemotherapy per year in the USA (ranging from 40,000 for a 10% reduction in efficacy to 280,000 for a 70% reduction in efficacy), and 6300 infection-related deaths (range: 2100 for a 10% reduction in efficacy, to 15,000 for a 70% reduction). We estimated that every year, 13,120 infections (42%) after prostate biopsy are attributable to resistance to fluoroquinolones in the USA.

INTERPRETATION

Increasing antibiotic resistance potentially threatens the safety and efficacy of surgical procedures and immunosuppressing chemotherapy. More data are needed to establish how antibiotic prophylaxis recommendations should be modified in the context of increasing rates of resistance.

FUNDING

DRIVE-AB Consortium.

Novel citation-based search method for scientific literature: application to meta-analyses

Background

Finding eligible studies for meta-analysis and systematic reviews relies on keyword-based searching as the gold standard, despite its inefficiency. Searching based on direct citations is not sufficiently comprehensive. We propose a novel strategy that ranks articles on their degree of co-citation with one or more “known” articles before reviewing their eligibility.

Method

In two independent studies, we aimed to reproduce the results of literature searches for sets of published meta-analyses (n = 10 and n = 42). For each meta-analysis, we extracted co-citations for the randomly selected ‘known’ articles from the Web of Science database, counted their frequencies and screened all articles with a score above a selection threshold. In the second study, we extended the method by retrieving direct citations for all selected articles.

Results

In the first study, we retrieved 82 % of the studies included in the meta-analyses while screening only 11 % as many articles as were screened for the original publications. Articles that we missed were published in non-English languages, published before 1975, published very recently, or available only as conference abstracts. In the second study, we retrieved 79 % of included studies while screening half the original number of articles.

Conclusions

Citation searching appears to be an efficient and reasonably accurate method for finding articles similar to one or more articles of interest for meta-analysis and reviews.

Electronic supplementary material

The online version of this article (doi:10.1186/s12874-015-0077-z) contains supplementary material, which is available to authorized users.