Antisepsis of the skin before spinal surgery with povidone iodine-alcohol followed by chlorhexidine gluconate-alcohol versus povidone iodine-alcohol applied twice for the prevention of contamination of the wound by bacteria: a randomised controlled trial

Povidone Iodine vs Chlorhexidine Gluconate for Preoperative Skin Antisepsis: A Systematic Review and Meta-analysis of Randomised Controlled Trials

BACKGROUND

Surgical site infection (SSI) remains a challenge in healthcare, contributing to prolonged hospital stays, increased healthcare costs, and adverse patient outcomes, including mortality. Effective preoperative skin disinfection interventions, such as povidone-iodine (PVI) and chlorhexidine (CHG), are widely used but their efficacy remains debated. To address this gap, this meta-analysis aims to evaluate the efficacy of PVI and CHG.

METHOD

We searched PubMed, Embase, and Cochrane databases up to June 2024 to identify studies comparing PVI versus CHG for preoperative skin antisepsis. We calculated odds ratios (ORs) for binary outcomes, with 95% confidence intervals (CIs). A random-effects model was used with statistical significance set at p < 0.05. Data were analysed using R software (version 4.4.0), and heterogeneity was assessed using I2 statistics.

FINDINGS

Sixteen randomised controlled trials (RCTs) were included, involving a total of 13,721 patients, among whom 6,836 (49.8%) received PVI. Compared to CHG, PVI was associated with a non-significant reduction in deep SSI (OR 1.00; 95% CI 0.66 - 1.50; p = 0.994), but an increased risk of overall SSI (OR 1.25; 95% CI 1.06 - 1.48; p = 0.007) and superficial SSI (OR 1.67; 95% CI 1.25 - 2.24; p < 0.001).

CONCLUSION

PVI as preoperative skin antisepsis demonstrated a non-significant reduction in deep SSI compared to CHG but was associated with an increased risk of overall and superficial SSI. Despite these findings, PVI remains an effective option, especially in resource-limited settings. Further research is needed to optimise its use and improve infection prevention strategies in clinical practice.

Which antiseptic to use for a caesarean section? A systematic review and network meta-analysis of randomized controlled trials

Guidelines for pre-operative skin antisepsis recommend using chlorhexidine in an alcohol-based solution. However, other antiseptics such as aqueous povidone-iodine or alcohol-based solutions continue to be used. Randomized controlled trials (RCTs) in caesarean section are rare and do not include all possible comparisons of antiseptics. The aim of this study was to assess the efficacy (reduction of surgical site infections) of chlorhexidine at two different concentrations (0.3% and 2%) and povidone-iodine in aqueous or alcohol-based solutions using a network meta-analysis, including only RCTs of caesarean sections. Fragility indices and prediction intervals were also estimated. A systematic literature review and network meta-analysis were performed. RCTs published up to February 2024 were collected from PubMed, ScienceDirect and the Cochrane Library. Interventions included alcohol-based povidone-iodine, aqueous povidone-iodine, and alcohol-based chlorhexidine 2% and 0.3%. The primary outcome measure was surgical site infection. Nine RCTs with 4915 patients and four interventions were included in the network meta-analysis. All credible intervals of the compared interventions overlapped. Alcohol-based 2% chlorhexidine had the highest probability of being effective in preventing surgical site infections, followed by alcohol-based povidone-iodine. The fragility index ranged from 4 to 18. The prediction intervals were wide. On the basis of rank probabilities, chlorhexidine 2% in an alcohol-based solution was most likely to be effective in preventing surgical site infections after caesarean section, followed by alcohol-based povidone-iodine. Given the paucity of literature and the relatively small difference between povidone-iodine and chlorhexidine found in our meta-analysis, we suggest that either can be used in an alcohol-based solution as antisepsis for planned or emergency caesarean section.

Shotgun sequencing of sonication fluid for the diagnosis of orthopaedic implant-associated infections with Cutibacterium acnes as suspected causative agent

Orthopaedic implant-associated infections (OIAIs) due to Cutibacterium acnes can be difficult to diagnose. The aim of this pilot study was to determine if metagenomic next-generation sequencing (mNGS) can provide additional information to improve the diagnosis of C. acnes OIAIs. mNGS was performed on sonication fluid (SF) specimens derived from 24 implants. These were divided into three groups, based on culture results: group I, culture-negative (n = 4); group II, culture-positive for C. acnes (n = 10); and group III, culture-positive for other bacteria (n = 10). In group I, sequence reads from C. acnes were detected in only one SF sample, originating from a suspected case of OIAIs, which was SF and tissue culture-negative. In group II, C. acnes sequences were detected in 7/10 samples. In group III, C. acnes sequence reads were found in 5/10 samples, in addition to sequence reads that matched the bacterial species identified by culture. These samples could represent polymicrobial infections that were missed by culture. Taken together, mNGS was able to detect C. acnes DNA in more samples compared to culture and could be used to identify cases of suspected C. acnes OIAIs, in particular regarding possible polymicrobial infections, where the growth of C. acnes might be compromised due to a fast-growing bacterial species. However, since SF specimens are usually low-biomass samples, mNGS is prone to DNA contamination, possibly introduced during DNA extraction or sequencing procedures. Thus, it is advisable to set a sequence read count threshold, taking into account project- and NGS-specific criteria.

Effective Biofilm Eradication on Orthopedic Implants with Methylene Blue Based Antimicrobial Photodynamic Therapy In Vitro

Periprosthetic joint infections (PJI) are difficult to treat due to biofilm formation on implant surfaces, often requiring removal or exchange of prostheses along with long-lasting antibiotic treatment. This in vitro study investigated the effect of methylene blue photodynamic therapy (MB-PDT) on PJI-causing biofilms on different implant materials. MB-PDT (664 nm LED, 15 J/cm²) was tested on different Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Cutibacterium acnes strains in both planktonic form and grown in early and mature biofilms on prosthetic materials (polyethylene, titanium alloys, cobalt-chrome-based alloys, and bone cement). The minimum bactericidal concentration with 100% killing (MBC_100%) was determined. Chemical and topographical alterations were investigated on the prosthesis surfaces after MB-PDT. Results showed a MBC_100% of 0.5-5 μg/mL for planktonic bacteria and 50-100 μg/mL for bacteria in biofilms-independent of the tested strain, the orthopedic material, or the maturity of the biofilm. Material testing showed no relevant surface modification. MB-PDT effectively eradicated common PJI pathogens on arthroplasty materials without damage to the materials, suggesting that MB-PDT could be used as a novel treatment method, replacing current, more invasive approaches and potentially shortening the antibiotic treatment in PJI. This would improve quality of life and reduce morbidity, mortality, and high health-care costs.

Efficacy comparison of chlorhexidine and iodine preparation in reduction of surgical site infection: A systemic review and meta-analysis

BACKGROUND

Chlorhexidine and povidone-iodine are the most common disinfectants used in preoperative skin preparation. However, there is no consistent conclusion regarding the prevention of surgical site infection (SSI) and bacterial culture data.

OBJECTIVE

To assess the efficacy of chlorhexidine and povidone-iodine in the prevention of postoperative SSI and relevant bacterial data.

DESIGN

Systematic Review and Meta-Analysis SETTINGS: N/A PARTICIPANTS: N/A METHOD: Literature relevant to "skin antisepsis" and "surgical site infections" was retrieved from PUBMED, Web of Science, EMBASE, CINHAL and CNKI. The incidence of SSI was the primary outcome, while the secondary outcome was bacterial data from the infected incision. All data were analyzed with Revman 5.3 and Stata Statistical Software.

RESULTS

A total of 36 studies were identified in this study, which included 16,872 participants. This study revealed that chlorhexidine is superior to povidone-iodine in the prevention of postoperative SSI (risk ratio [RR], 0.73; 95% confidence interval [CI], 0.61-0.87; p = 0.019, I² = 39%). Further meta-regression analysis revealed that the effect of chlorhexidine was directly associated with the type of incision, but failed to differentiate between the subgroups divided according to the type of incision. With respect to bacteria colonization, the most common bacteria for chlorhexidine arm were propionibacterium's, while the most common bacteria for the iodine arm were staphylococci species.

CONCLUSION

In comparison to povidone-iodine, chlorhexidine showed better results in preventing postoperative SSI.

Examining the effect of wound cleansing on the microbiome of venous stasis ulcers

Common treatment for venous leg wounds includes topical wound dressings with compression. At each dressing change, wounds are debrided and washed; however, the effect of the washing procedure on the wound microbiome has not been studied. We hypothesized that wound washing may alter the wound microbiome. To characterize microbiome changes with respect to wound washing, swabs from 11 patients with chronic wounds were sampled before and after washing, and patient microbiomes were characterized using 16S rRNA sequencing and culturing. Microbiomes across patient samples prior to washing were typically polymicrobial but varied in the number and type of bacterial genera present. Proteus and Pseudomonas were the dominant genera in the study. We found that washing does not consistently change microbiome diversity but does cause consistent changes in microbiome composition. Specifically, washing caused a decrease in the relative abundance of the most highly represented genera in each patient cluster. The finding that venous leg ulcer wound washing, a standard of care therapy, can induce changes in the wound microbiome is novel and could be potentially informative for future guided therapy strategies.

Disinfectants In Interventional Practices

PURPOSE OF REVIEW

This review aims to provide relevant, aggregate information about a variety of disinfectants and antiseptics, along with potential utility and limitations. While not exhaustive, this review's goal is to add to the body of literature available on this topic and give interventional providers and practitioners an additional resource to consider when performing procedures.

RECENT FINDINGS

In the current SARS-CoV2 epidemiological environment, infection control and costs associated with healthcare-associated infections (HAIs) are of paramount importance. Even before the onset of SARS-CoV2, HAIs affected nearly 2million patients a year in the USA and resulted in nearly 90,000 deaths, all of which resulted in a cost to hospitals ranging from US$28 billion to 45 billion. The onset SARS-CoV2, though not spread by an airborne route, has heightened infection control protocols in hospitals and, as such, cast a renewed focus on disinfectants and their utility across different settings and organisms. The aim of this review is to provide a comprehensive overview of disinfectants used in the inpatient setting.

Pathway for enhanced recovery after spinal surgery-a systematic review of evidence for use of individual components

BACKGROUND

Enhanced recovery in spinal surgery (ERSS) has shown promising improvements in clinical and economical outcomes. We have proposed an ERSS pathway based on available evidence. We aimed to delineate the clinical efficacy of individual pathway components in ERSS through a systematic narrative review.

METHODS

We included systematic reviews and meta-analysis, randomized controlled trials, non-randomized controlled studies, and observational studies in adults and pediatric patients evaluating any one of the 22 pre-defined components. Our primary outcomes included all-cause mortality, morbidity outcomes (e.g., pulmonary, cardiac, renal, surgical complications), patient-reported outcomes and experiences (e.g., pain, quality of care experience), and health services outcomes (e.g., length of stay and costs). Following databases (1990 onwards) were searched: MEDLINE, EMBASE, and Cochrane Library (Cochrane Database of Systematic Reviews and CENTRAL). Two authors screened the citations, full-text articles, and extracted data. A narrative synthesis was provided. We constructed Evidence Profile (EP) tables for each component of the pathway, where appropriate information was available. Due to clinical and methodological heterogeneity, we did not conduct a meta-analyses. GRADE system was used to classify confidence in cumulative evidence for each component of the pathway.

RESULTS

We identified 5423 relevant studies excluding duplicates as relating to the 22 pre-defined components of enhanced recovery in spinal surgery. We included 664 studies in the systematic review. We identified specific evidence within the context of spinal surgery for 14/22 proposed components. Evidence was summarized in EP tables where suitable. We performed thematic synthesis without EP for 6/22 elements. We identified appropriate societal guidelines for the remainder of the components.

CONCLUSIONS

We identified the following components with high quality of evidence as per GRADE system: pre-emptive analgesia, peri-operative blood conservation (antifibrinolytic use), surgical site preparation and antibiotic prophylaxis. There was moderate level of evidence for implementation of prehabilitation, minimally invasive surgery, multimodal perioperative analgesia, intravenous lignocaine and ketamine use as well as early mobilization. This review allows for the first formalized evidence-based unified protocol in the field of ERSS. Further studies validating the multimodal ERSS framework are essential to guide the future evolution of care in patients undergoing spinal surgery.

Pro-Inflammatory and Neurotrophic Factor Responses of Cells Derived from Degenerative Human Intervertebral Discs to the Opportunistic Pathogen Cutibacterium acnes

Previously, we proposed the hypothesis that similarities in the inflammatory response observed in acne vulgaris and degenerative disc disease (DDD), especially the central role of interleukin (IL)-1β, may be further evidence of the role of the anaerobic bacterium Cutibacterium (previously Propionibacterium) acnes in the underlying aetiology of disc degeneration. To investigate this, we examined the upregulation of IL-1β, and other known IL-1β-induced inflammatory markers and neurotrophic factors, from nucleus-pulposus-derived disc cells infected in vitro with C. acnes for up to 48 h. Upon infection, significant upregulation of IL-1β, alongside IL-6, IL-8, chemokine (C-C motif) ligand 3 (CCL3), chemokine (C-C motif) ligand 4 (CCL4), nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF), was observed with cells isolated from the degenerative discs of eight patients versus non-infected controls. Expression levels did, however, depend on gene target, multiplicity and period of infection and, notably, donor response. Pre-treatment of cells with clindamycin prior to infection significantly reduced the production of pro-inflammatory mediators. This study confirms that C. acnes can stimulate the expression of IL-1β and other host molecules previously associated with pathological changes in disc tissue, including neo-innervation. While still controversial, the role of C. acnes in DDD remains biologically credible, and its ability to cause disease likely reflects a combination of factors, particularly individualised response to infection.

Cutibacterium avidum resists surgical skin antisepsis in the groin-a potential risk factor for periprosthetic joint infection: a quality control study

BACKGROUND

The skin commensal Cutibacterium avidum has been recognized as an emerging pathogen for periprosthetic joint infections (PJI). One currently assumes that the early occurring PJIs are a consequence of skin commensals contaminating the peri-implant tissue during surgery. We addressed whether standard skin antisepsis with povidone-iodine/alcohol before total hip arthroplasty (THA) is effective to eliminate colonizing bacteria with focus on C. avidum.

METHODS

In a single-center, prospective study, we screened all patients for skin colonizing C. avidum in the groin before THA. Only in the patients positive for C. avidum, we preoperatively repeated skin swabs after the first and third skin antisepsis and antibiotic prophylaxis. We also obtained dermis biopsies for microbiology and fluorescence in situ hybridization (FISH).

RESULTS

Fifty-one out of 60 patients (85%) were colonized on the skin with various bacteria, in particular with C. avidum in 12 out of 60. Skin antisepsis eliminated C. avidum in eight of ten (20%) colonized patients undergoing THA. Deeper skin (dermis) biopsies were all culture negative, but FISH detected single positive ribosome-rich C. avidum in one case near sweat glands.

CONCLUSION

Standard skin antisepsis was not effective to completely eliminate colonizing C. avidum on the skin in the groin of patients undergoing THA. Colonizing with C. avidum might pose an increased risk for PJI when considering a THA. Novel more effective antisepsis strategies are needed. Trial registration No clinical trial.

Preparación de la piel para la prevención de la Infección del Sitio Operatorio: Revisión de Alcance

Introducción: La Infección del sitio operatorio genera un impacto económico y social debido a los altos costos durante la recuperación, la estancia hospitalaria y la afectación de la calidad de vida, por esto, es necesario identificar las intervenciones y recomendaciones para la preparación de la piel, encaminadas a la prevención de la infección del sitio operatorio, basado en la evidencia científica. Materiales y Métodos: Se realizó una revisión sistemática de alcance en el marco del Instituto Joanna Briggs y los parámetros Prisma-P. En las bases de datos Medline, OVID, Pubmed, Scielo, BVS y Cochrane, publicadas entre los años 2010–2019, en los idiomas inglés, portuges y español. Resultados: Se analizaron 28 artículos. De estos, se identificaron 6 de la categoría general incluidas las guías de prevención de infección del sitio operatorio, 6 para el baño preoperatorio, 6 para la realización del rasurado y 10 de asepsia y antisepsia. Discusión: Con respecto al baño preoperatorio, es una práctica recomendada internacionalmente, la evidencia demuestra que esta actividad no representa ningún beneficio; en la categoría de rasurado, la recomendación es no remover el vello a menos que sea absolutamente necesario. Frente a la asepsia del sitio quirúrgico, el aporte es más que todo informativo acerca de los antisépticos y se recomienda el uso de la clorhexidina. Conclusiones: De acuerdo a la revisión sistemática de alcance de la literatura, no se evidencia una estandarización en las recomendaciones e intervenciones, para la preparación de la piel en la prevención de Infección del Sitio Operatorio.

Preoperative Antisepsis with Chlorhexidine Versus Povidone-Iodine for the Prevention of Surgical Site Infection: a Systematic Review and Meta-analysis

BACKGROUND AND OBJECTIVE

Chlorhexidine (CH) and povidone-iodine (PI) are the most commonly used preoperative skin antiseptics at present. However, the prevention of the surgical site infection (SSI) and the incidence of skin adverse events do not reach a consistent statement and conclusion. This meta-analysis aimed to evaluate the efficacy of chlorhexidine and povidone-iodine in the prevention of postoperative surgical site infection and the incidence of corresponding skin adverse events.

METHOD

Substantial studies related to "skin antiseptic" and "surgical site infection" were consulted on PUBMED, Web of Science, EMBASE, and CNKI. The primary outcome was the incidence of postoperative SSI. The secondary outcome was associated with skin adverse events. All data were analyzed with Revman 5.3 software.

RESULTS

A total of 30 studies were included, including 29,006 participants. This study revealed that chlorhexidine was superior to povidone-iodine in the prevention of postoperative SSI (risk ratio [RR], 0.65; 95% confidence interval [CI], 0.55-0.77; p < 0.00001, I² = 57%). Further subgroup analysis showed that chlorhexidine was superior to povidone-iodine in the prevention of postoperative SSI in clean surgery (risk ratio [RR], 0.81; 95% confidence interval [CI], 0.67-0.98; p = 0.03), I² = 28%) and clean-contaminated surgery (risk ratio [RR], 0.58; 95% confidence interval [CI], 0.47-0.73; p < 0.00001, I² = 43%). However, there was no statistically significant difference in the incidence of skin adverse events between CH and PI groups.

CONCLUSION

Chlorhexidine was superior to povidone-iodine in preventing postoperative SSI, especially for the clean-contaminated surgery. However, there was no statistically significant difference in the incidence of skin adverse events between CH and PI groups.

Bacterial skin recolonization in the operating room: comparison between various antisepsis protocols

BACKGROUND

Surgical site infection (SSI) largely implicates the patient's endogenous skin microbiota. Perioperative disinfection protocols do not follow a general agreement.

AIM

To compare antisepsis and skin protection protocols on quantitative analysis of recolonization in the operating room at regular time-steps. The study hypothesis was that one protocol would be more effective than others.

METHODS

A single-centre prospective interventional study was conducted between January and June 2019. Healthy volunteers were randomized between protocols and served as their own controls. The protocols began ahead of scheduled orthopaedic surgery with a preoperative shower, mechanical cleansing, application of major antiseptics (alcoholic Bétadine™ 5% or alcoholic chlorhexidine 0.5%), sterile draping, then adhesive draping (3M™ Steri-Drape™ or iodine-impregnated 3M™ Ioban2™). Sampling was by swabbing in the operating room at 30 min intervals up to 90 min after draping. Cultures were performed under aerobic and anaerobic conditions. Qualitative and quantitative (cfu/mL) bacteriology was performed in the laboratory by direct reading on the blood agar plates.

FINDINGS

Thirty subjects were included; none was lost to follow-up or excluded from analysis. Bacterial load before manipulation (T0) was significantly higher in males (P < 0.0001) despite a significantly shorter shower-to-sampling interval (P = 0.03). Smoking (P = 0.85), body mass index (P = 0.38), and depilation (P = 0.50) did not significantly affect preoperative load. Mean load increased significantly under all protocols up to T90 min, without significant superiority for any one protocol. Associated Bétadine™/Ioban™ showed the lowest T90 load, and chlorhexidine alone the highest, but without significant difference. Isolates at T0 were predominantly healthy skin commensals: coagulase-negative staphylococci, micrococci, and coryneforms.

CONCLUSION

No one protocol demonstrated superiority, whether in immediate bactericidal action or in preventing skin recolonization in the operating room. Further studies are needed to define generally agreed protocols for SSI risk management.

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.

Sequential use of povidone-iodine and chlorhexidine for cutaneous antisepsis: A systematic review

Cutaneous antisepsis with chlorhexidine or povidone-iodine, usually with alcohol, has been extensively studied. This review of published studies reveals that sequential use of povidone-iodine and chlorhexidine leads to a greater reduction in the bioburden of aerobic and anaerobic bacteria on the skin, lower risk of intravascular catheter colonization, and lower risk of surgical site infection compared to use of either agent alone. As such, sequential use of cutaneous antiseptic agents may further reduce risk of surgical site infections, as well as infections associated with insertion of transdermal devices such as nephrostomy tubes, left-ventricular assistance devices, and intravascular catheters.

Propionibacterium acnes and Acne Vulgaris: New Insights from the Integration of Population Genetic, Multi-Omic, Biochemical and Host-Microbe Studies

The anaerobic bacterium Propionibacterium acnes is believed to play an important role in the pathophysiology of the common skin disease acne vulgaris. Over the last 10 years our understanding of the taxonomic and intraspecies diversity of this bacterium has increased tremendously, and with it the realisation that particular strains are associated with skin health while others appear related to disease. This extensive review will cover our current knowledge regarding the association of P. acnes phylogroups, clonal complexes and sequence types with acne vulgaris based on multilocus sequence typing of isolates, and direct ribotyping of the P. acnes strain population in skin microbiome samples based on 16S rDNA metagenomic data. We will also consider how multi-omic and biochemical studies have facilitated our understanding of P. acnes pathogenicity and interactions with the host, thus providing insights into why certain lineages appear to have a heightened capacity to contribute to acne vulgaris development, while others are positively associated with skin health. We conclude with a discussion of new therapeutic strategies that are currently under investigation for acne vulgaris, including vaccination, and consider the potential of these treatments to also perturb beneficial lineages of P. acnes on the skin.

Current preoperative antisepsis in neurosurgery: an example of the challenges in implementing evidence-based medicine to surgical practice

INTRODUCTION

Surgical site infection is associated with significant morbidity and mortality. Effective preoperative skin decolonisation is an important preventative strategy. The National Institute for Health and Care Excellence clinical guidelines recommend decolonisation using chlorhexidine gluconate (CHG) or povidone iodine (PVI). Current evidence indicates that CHG is more effective, while the combination of CHG and PVI is greater still. This study describes current practice among neurosurgeons in the UK, including differences between trainees and consultants, to review compliance with the latest evidence.

MATERIALS AND METHODS

A Society of British Neurosurgical Surgeons approved national, multicentre questionnaire was circulated online. A total of 74 complete responses were obtained from 27 trainees and 47 consultants, representing 28 of 37 neurosurgical centres.

RESULTS

Of the total responding centres, 36 (49%) used a single agent and 38 (51%) used a dual-agent preparation. One respondent used Tisept®. Seventy (95%) used alcohol in some form and none used aqueous CHG. Trainees were more likely to use a dual-agent preparation (P = 0.025). Forty-seven (63%) prepared the skin three or more times, with trainees preparing the skin more times than consultants (P = 0.002).

CONCLUSION

Neurosurgical practice adheres to national clinical guidelines but not the latest evidence from the literature. Given the weighting placed on randomised controlled trials, such a trial may be required to standardise practice that is likely to reduce surgical site infection.

A state of the art review on optimal practices to prevent, recognize, and manage complications associated with intravascular devices in the critically ill

Intravascular catheters are inserted into almost all critically ill patients. This review provides up-to-date insight into available knowledge on epidemiology and diagnosis of complications of central vein and arterial catheters in ICU. It discusses the optimal therapy of catheter-related infections and thrombosis. Prevention of complications is a multidisciplinary task that combines both improvement of the process of care and introduction of new technologies. We emphasize the main component of the prevention strategies that should be used in critical care and propose areas of future investigation in this field.

Over a Decade of recA and tly Gene Sequence Typing of the Skin Bacterium Propionibacterium acnes: What Have We Learnt?

The Gram-positive, anaerobic bacterium Propionibacterium acnes forms part of the normal microbiota on human skin and mucosal surfaces. While normally associated with skin health, P. acnes is also an opportunistic pathogen linked with a range of human infections and clinical conditions. Over the last decade, our knowledge of the intraspecies phylogenetics and taxonomy of this bacterium has increased tremendously due to the introduction of DNA typing schemes based on single and multiple gene loci, as well as whole genomes. Furthermore, this work has led to the identification of specific lineages associated with skin health and human disease. In this review we will look back at the introduction of DNA sequence typing of P. acnes based on recA and tly loci, and then describe how these methods provided a basic understanding of the population genetic structure of the bacterium, and even helped characterize the grapevine-associated lineage of P. acnes, known as P. acnes type Zappe, which appears to have undergone a host switch from humans-to-plants. Particular limitations of recA and tly sequence typing will also be presented, as well as a detailed discussion of more recent, higher resolution, DNA-based methods to type P. acnes and investigate its evolutionary history in greater detail.