Current preventive measures for health-care associated surgical site infections: a review

Surgical Marking Pen Contamination: Writing a Postoperative Infection Into Your Preoperative Plan

Introduction Preoperative marking is an essential safety practice to prevent "never" events, including wrong site surgery. Moreover, the Joint Commission regulations of the Universal Protocol require that patients be marked to indicate the operative site. Marking typically occurs with a pen or marker, which may be disposable or reusable. Previous studies have demonstrated that methicillin-resistant Staphylococcus aureus (MRSA) can survive in the dark, moist, capped environment of the marking pen and thus could plausibly be a nidus for transmission from patient to patient. The Joint Commission has established no increased risk of postoperative infection with these markings. With this study, we aimed to determine the colonization of surgical marking pens in the plastic surgery population. Methods Two marking pens from five different attending plastic surgeons at a single institution were cultured in standard fashion for aerobic and anaerobic growth. All pens were used repeatedly in office settings for performing patient markings. Those same ten marking pens were then used to mark incision sites on mock patients. Standard povidone-iodine prepping was then performed in a paint-only fashion over the skin markings, and cultures were again taken. A control group consisted of cultures from five sterile pens from the operating room. Each sterile pen was opened, uncapped, and then swabbed. All twenty-five cultures were analyzed in the hospital laboratory in a blinded fashion. Results The five control pens revealed no bacterial growth. Of the 10 direct pen cultures, two samples grew coagulase-negative staphylococci and one culture contained Pseudomonas aeruginosa. The 10-patient marked and prepped specimens showed eight negative cultures and two with coagulase-negative staphylococci. Although Pseudomonas was detected on standard pen culture, no pseudomonal growth was present in any of the samples after patient marking and prepping with povidone-iodine. Conclusions Our findings reaffirm that marking pens may be vehicles for bacterial transmission and expand upon previous studies by describing the presence of bacterial colonization on marking pens even after surgical site preparation with povidone-iodine.

The susceptibility of multidrug resistant and biofilm forming Klebsiella pneumoniae and Escherichia coli to antiseptic agents used for preoperative skin preparations at zonal referral hospital in Mwanza, Tanzania

Background

Non-susceptibility of bacteria to antiseptic agents used for preoperative skin preparations threaten the effectiveness of prevention of surgical site infections. Data concerning susceptibility of multidrug resistant bacteria strains to antiseptic agents was limited at our setting. This study presents the susceptibility of extended spectrum β-lactamases producing Klebsiella pneumoniae and Escherichia coli (with and without biofilm formation) to antiseptic agents used for preoperative skin preparations at zonal referral hospital in Mwanza, Tanzania.

Methods

This cross-sectional descriptive study was conducted through July 2020. Presumptive extended spectrum beta-lactamase producing Klebsiella pneumoniae and Escherichia coli were recovered for this study. Disc combination method was used to confirm production of ESBL while tube method was used to detect biofilms formation. Then, isolates were tested for susceptibility towards 10% povidone iodine, 70% methylated spirit, 50% hydrogen peroxide (6% of industrial H₂O₂ diluted in equal volume with sterile distilled water) and 2% chlorhexidine. STATA software version 13.0 was used for data analysis.

Results

A total of 31 presumptive ESBL producers were recovered and phenotypically confirmed, whereas 54.8% (n=17) were K. pneumoniae and 45.2% (n=14) were E. coli. Five (35.7%) E. coli and seven (41.2%) K. pneumoniae had positive biofilms test results. Four (12.9%) bacteria were non-susceptible to antiseptic agents used for preoperative skin preparations. However, none exhibited resistance towards 10% PVP-I.

Conclusion

In this study we highlight the existence of multidrug resistant Gram-negative bacteria with resistance to antiseptic agents used for preoperative skin preparation at a zonal referral hospital in Mwanza, Tanzania.

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.

Time-dependent surgical instrument contamination begins earlier in the uncovered table than in the covered table

PURPOSE

Time-dependent surgical instrument contamination and the effect of covering during arthroplasty have not been investigated. This study aimed to evaluate time-dependent contamination of surgical instruments and the effect of covering on contamination as well as to perform bacterial typing of contaminated samples. The hypothesis was that covering the surgical instruments would decrease contamination rates.

METHODS

Sixty patients who underwent total knee arthroplasty were randomized and divided into two groups: surgical instruments covered with a sterile towel or surgical instruments left uncovered. K-wires were used to extract microbiological samples. The K-wires were placed in a liquid culture medium at 0, 15, 30, 60, 90, and 120 min. After 24-h incubation period, samples from liquid cultures were cultured on blood agar using swabs. Samples with growth after 48 h were considered contaminated. Microscopic, staining, and biochemical properties were used for bacterial typing.

RESULTS

Bacterial growth started after 30 and 60 min in the uncovered and covered groups, respectively. An increase in the number of K-wires contaminated with time was detected. At least 10,000 CFU/mL bacterial load was observed in the culture samples. Contamination was more significant in the uncovered group. A statistically significant difference in contamination was found between the uncovered and covered groups at 30-, 60-, 90-, and 120 min (p = 0.035, p = 0.012, p = 0.024, and p = 0.037, respectively). The most common bacteria on the contaminated instruments were coagulase-negative Staphylococci (60.4%), Staphylococcus aureus (22.9%), and Streptococcus agalactia (16.7%), respectively.

CONCLUSION

The risk of contamination increases with time. However, it may decrease if surgical instruments are covered. In the clinical practice, empiric antibiotic regimens based on the type of identified microorganisms in this study may be developed for postoperative periprosthetic joint infection prophylaxis.

LEVEL OF EVIDENCE

Prognostic, Level II.

Antimicrobial coating of spider silk to prevent bacterial attachment on silk surgical sutures

Microbial infections from post-surgery or other medical-related procedure is a serious health problem. Nowadays, the research is focused on the development of new drug-free materials with antibacterial properties to prevent or minimize the risk of infections. Spider silk is known for its unique biomechanical properties allied with biocompatibility. Recombinant DNA technology allows to bioengineering spider silk with antimicrobial peptides (AMP). Thus, our goal was to bioengineered spider silk proteins with AMP (6mer-HNP1) as an antibacterial drug-free coating for commercial silk sutures (Perma-Hand®) for decreasing bacterial infections. Perma-Hand® sutures were coated with 6mer-HNP1 by dip coating. In vitro tests, using human fetal lung fibroblasts (MRC5), showed that coated sutures sustained cell viability, and also, the contact with red blood cells (RBCs) demonstrate blood compatibility. Also, the coatings inhibited significantly the adherence and formation of biofilm, where sutures coated with 6mer-HNP1 produced a 1.5 log reduction of Methicillin-Resistant Staphylococcus aureus (MRSA) and a 2 log reduction of Escherichia coli (E. coli) compared to the uncoated Perma-Hand® suture. The mechanical properties of Perma-Hand® sutures were not affected by the presence of bioengineered spider silk proteins. Thus, the present work demonstrated that using spider silk drug-free coatings it is possible to improve the antibacterial properties of the commercial sutures. Furthermore, a new class of drug-free sutures for reducing post-implantation infections can be developed. STATEMENT OF SIGNIFICANCE: Microbial infections from post-surgery or other medical-related procedure is a serious health problem. Developing new drug-free materials with antibacterial properties is an approach to prevent or minimize the risk of infections. Spider silk is known for its unique biomechanical properties allied with biocompatibility. Recombinant DNA technology allow to bioengineering spider silk with antimicrobial peptides (AMP). Our goal is bioengineered spider silk proteins with AMP as an antibacterial coating for silk sutures. The coatings showed exceptional antibacterial properties and maintained intrinsic mechanical features. In vitro studies showed a positive effect of the coated sutures on the cell behavior. With this new drug-free bioengineered spider silk coating is possible to develop a new class of drug-free sutures for reducing post-implantation infections.

Operation Department: Infection Control

Infection control in the operation department is the result of many single factors and routines, based on experience, documentation and expert panels through more than a hundred years. Many factors and routines in surgery are evidence-based, but most of them are still lacking evidence and can probably never be investigated because of ethical problems. Consequently, consensus and guidance are used to a great extent. Surgery opens into sterile tissues for hours, where there is massive tissue damage by knife, diathermy, clogging of vessels, pressure against and drying of tissues, decreased blood supply, impaired phagocytosis and impaired infection defence. Microbes deposited in this devitalized tissues may find a good basis for growth and proliferation if there is lack of infection control and sterility. For patients with ongoing infections and who need surgery, special routines are made to prevent the spread of infections in the operation department. This chapter is a practical description of many important preventive procedures that may protect the surgical patient against surgical site infection (SSI).

Health care-associated infections - an overview

Health care-associated infections (HCAIs) are infections that occur while receiving health care, developed in a hospital or other health care facility that first appear 48 hours or more after hospital admission, or within 30 days after having received health care. Multiple studies indicate that the common types of adverse events affecting hospitalized patients are adverse drug events, HCAIs, and surgical complications. The US Center for Disease Control and Prevention identifies that nearly 1.7 million hospitalized patients annually acquire HCAIs while being treated for other health issues and that more than 98,000 patients (one in 17) die due to these. Several studies suggest that simple infection-control procedures such as cleaning hands with an alcohol-based hand rub can help prevent HCAIs and save lives, reduce morbidity, and minimize health care costs. Routine educational interventions for health care professionals can help change their hand-washing practices to prevent the spread of infection. In support of this, the WHO has produced guidelines to promote hand-washing practices among member countries.

Removal of Staphylococcus aureus from skin using a combination antibiofilm approach

Staphylococcus aureus (S. aureus) including methicillin resistant S. aureus (MRSA) is one of the primary microorganisms responsible for surgical site infection (SSI). Since S. aureus contamination is known to originate from the skin, eradicating it on the skin surface at surgical sites is an important intervention to reduce the chance of SSIs. Here we developed and evaluated the efficacy of a combination probiotic/brush sonication strategy for skin preparation at surgical, injection and insertion sites in medicine. A 24 h biofilm on porcine skin explants was used as a worst-case scenario for the evaluation of preparation strategies. Conventional ethanol wipes achieved 0.8~2 log reduction in viable bacteria depending on how many times wiped (x4 or x6). Brush sonication or probiotic supernatant pre-treatment alone achieved a similar reduction as ethanol wipes (1.4 and 0.7~1.4 log reduction, respectively). Notably, combining sonication and probiotic pre-treatment achieved a 4 log reduction in viable bacteria. In addition, probiotic supernatant incubation times as short as 2 h achieved the full effect of this reduction in the combined strategy. These findings suggest the promising potential of combination-format skin preparation strategies that can be developed to more effectively penetrate cracks and folds in the skin to remove biofilms.

Combining brush sonication with secretions from probiotic bacteria cleans skin before surgery more effectively than ethanol wipes. Researchers in the USA, led by K. Scott Phillips at the United States Food and Drug Administration, investigated removal of Staphylococcus aureus biofilm from pig skin as a “worst case” pre-surgical scenario. This bacterium is a major cause of serious and drug-resistant surgical site infections. Brush sonication or treatment with probiotic-derived solutions were individually approximately as effective as ethanol wipes, but in combination they proved substantially more effective. The treatment with the secretions surrounding probiotic bacterial cells requires exposure for several hours, but this could be readily achieved using a pre-surgery ointment. The sonication and probiotic combination could be developed into a highly effective pre-surgical procedure, penetrating cracks and folds in the skin to remove dangerous biofilms.

1α,25-dihydroxyvitamin D3-eluting nanofibrous dressings induce endogenous antimicrobial peptide expression

AIM

The aim of this study was to develop a nanofiber-based dressing capable of local sustained delivery of 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) and augmenting human CAMP induction.

MATERIALS & METHODS

Nanofibrous wound dressings containing 1,25(OH)2D3 were successfully prepared by electrospinning, which were examined in vitro, in vivo and ex vivo.

RESULTS

1,25(OH)2D3 was successfully loaded into nanofibers with encapsulation efficiency larger than 90%. 1,25(OH)2D3 showed a sustained release from nanofibers over 4 weeks. Treatment of U937 and HaCaT cells with 1,25(OH)2D3-loaded poly(ϵ-caprolactone) nanofibers significantly induced hCAP18/LL37 expression in monocytes and keratinocytes, skin wounds of humanized transgenic mice and artificial wounds of human skin explants.

CONCLUSION

1,25(OH)2D3 containing nanofibrous dressings could enhance innate immunity by inducing antimicrobial peptide production.

The Association Between Operating Room Personnel and Turnover With Surgical Site Infection in More Than 12 000 Neurosurgical Cases

BACKGROUND

Surgical site infection (SSI) contributes significantly to postoperative morbidity and mortality and greatly increases the cost of care.

OBJECTIVE

To identify the impact of workflow and personnel-related risk factors contributing to the incidence of SSIs in a large sample of neurological surgeries.

METHODS

Data were obtained using an enterprisewide electronic health record system, operating room, and anesthesia records for neurological procedures conducted between January 1, 2009, and November 30, 2012. SSI data were obtained from prospective surveillance by infection preventionists using Centers for Disease Control and Prevention definitions. A multivariate model was constructed and refined using backward elimination logistic regression methods.

RESULTS

The analysis included 12 528 procedures. Most cases were elective (94.5%), and the average procedure length was 4.8 hours. The average number of people present in the operating room at any time during the procedure was 10.0. The overall infection rate was 2.3%. Patient body mass index (odds ratio, 1.03; 95% confidence interval [CI], 1.01-1.04) and sex (odds ratio, 1.36; 95% CI, 1.07-1.72) as well as procedure length (odds ratio, 1.19 per additional hour; 95% CI, 1.15-1.23) and nursing staff turnovers (odds ratio, 1.095 per additional turnover; 95% CI, 1.02-1.21) were significantly correlated with the risk of SSI.

CONCLUSION

This study found that patient body mass index and male sex were associated with an increased risk of SSI. Operating room personnel turnover, a modifiable, work flow-related factor, was an independent variable positively correlated with SSI. This study suggests that efforts to reduce operating room turnover may be effective in preventing SSI.

ABBREVIATIONS

OR, operating roomSSI, surgical site infection.

A Simple Way to Eradicate Methicillin-Resistant Staphylococcus aureus in Cynomolgus Macaques (Macaca fascicularis)

Our investigation of indoor-housed cynomolgus macaques (Macaca fascicularis) by using automated identification followed by antibiotic susceptibility testing revealed 1 of 7 immunocompetent animals and 2 of 9 immunosuppressed monkeys as carriers of methicillin-resistant Staphylococcus aureus (MRSA). Follow-up management involving mupirocin treatment resulted in the conversion of the 3 MRSA carriers into MRSA-negative cases. Prospective assessment of newly imported monkeys involving 24-h culture of nasal swabs on chromogenic agar revealed that 22% (18 of 82 animals) were MRSA-positive. Mupirocin treatment successfully converted all of the MRSA-positive macaques into non-carriers, suggesting the feasibility of this simple, one-step screening procedure for rapidly identifying MRSA carriers in large cohorts. In addition, 8 animals that had been diagnosed MRSA-positive and subsequently treated with mupirocin demonstrated no recolonization during follow-up, even under immunosuppressive conditions. We propose rapid screening using chromogenic agar followed by mupirocin treatment as a time- and cost-effective regimen for managing MRSA in cynomolgus monkeys.

Developing professional habits of hand hygiene in intensive care settings: An action-research intervention

OBJECTIVES

To explore perceptions and unconscious psychological processes underlying handwashing behaviours of intensive care nurses, to implement organisational innovations for improving hand hygiene in clinical practice.

RESEARCH METHODOLOGY

An action-research intervention was performed in 2012 and 2013 in the intensive care unit of a public hospital in Italy, consisting of: structured interviews, semantic analysis, development and validation of a questionnaire, team discussion, project design and implementation. Five general workers, 16 staff nurses and 53 nurse students participated in the various stages.

RESULTS

Social handwashing emerged as a structured and efficient habit, which follows automatically the pattern "cue/behaviour/gratification" when hands are perceived as "dirty". The perception of "dirt" starts unconsciously the process of social washing also in professional settings. Professional handwashing is perceived as goal-directed. The main concern identified is the fact that washing hands requires too much time to be performed in a setting of urgency. These findings addressed participants to develop a professional "habit-directed" hand hygiene procedure, to be implemented at beginning of workshifts.

CONCLUSIONS

Handwashing is a ritualistic behaviour driven by deep and unconscious patterns, and social habits affect professional practice. Creating professional habits of hand hygiene could be a key solution to improve compliance in intensive care settings.

A controlled antibiotic release system to prevent orthopedic-implant associated infections: An in vitro study

A new device for local delivery of antibiotics is presented, with potential use as a drug-eluting fixation pin for orthopedic applications. The implant consists of a stainless steel hollow tubular reservoir packed with the desired antibiotic. Release takes place through several orifices previously drilled in the reservoir wall, a process that does not compromise the mechanical properties required for the implant. Depending on the antibiotic chosen and the number of orifices, the release profile can be tailored from a rapid release of the load (ca. 20 h) to a combination of rapid initial release and slower, sustained release for a longer period of time (ca. 200 h). An excellent bactericidal action is obtained, with 4-log reductions achieved in as little as 2 h, and total bacterial eradication in 8 h using 6-pinholed implants filled with cefazolin.