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Clinicians often perform pumping of infusions with a syringe (PIS) to quickly deliver fluid or blood transfusion to patients, especially during an emergency. Despite the efforts of the clinicians, critically ill patients are prone to acquire catheter-related bloodstream infections. Although clinicians have reported the possibility of PIS contamination, no group of researchers has studied nor confirmed this possibility. Here, we examined whether PIS can cause bacterial contamination of the fluid inside the syringes, using microbiological tests, including the analysis Escherichia coli DH-5 alpha growth by measuring the absorbance at OD 600 . We confirmed that contamination of fluid in the barrel was almost proportional to the applied volume of bacterial fluid. Aliquots of DH-5 alpha artificially applied on the surface of the gloved hand of an examiner, the plunger or the inner side of the barrel of a syringe could permeate inside the syringe. Furthermore, disinfection with ethanol before PIS almost successfully prevented bacterial multiplication. Our findings suggest that PIS can cause intraluminal contamination when performed with unsterilized hands, and that previous disinfection with ethanol can effectively prevent PIS-induced contamination. These results highlight the risk of PIS-induced contamination and the importance of disinfection in the daily clinical practice., (© 2021. The Author(s).)

Microbial cells can rapidly form biofilm on endotracheal tubes (ETT) causing ventilator-associated pneumonia, a serious complication in patients receiving mechanical ventilation. A novel polyamide with a good balance of hydrophilic/hydrophobic moieties was used for the embedment of green-reduction silver nanoparticles (AgNPs) for the composite-coated ETT. The films were conformal with a thickness of ∼ 17 ± 3 µm accommodating high loading of 60 ± 35 nm spherical-shaped AgNPs. The coated ETT resulted in a significant difference in reducing both planktonic growth and microbial adhesion of single and mixed-species cultures, compared with uncoated ETT ( p  < 0.05). A time-kill assay demonstrated rapid bactericidal effects of the coating on bacterial growth and cell adhesion to ETT surface. Biofilm formation by Pseudomonas aeruginosa and Staphylococcus aureus , commonly encountered pathogens, was inhibited by > 96% after incubation for 72 h. Polyamide/AgNP composite-coated ETT provided a broad-spectrum activity against both Gram-positive and Gram-negative bacteria as well as Candida albicans and prolonged antimicrobial activity.

Background: Overnight catheter drainage (OCD) is introduced to avoid overdistention of the bladder at night-time when clean intermittent catheterization proves ineffective for daytime management of neurogenic bladder. We adopted OCD using disposable silicone no-balloon (DSnB) catheters, with the distal end outside the body opening into diapers. OCD using DSnB catheter, however, had risks of retrograde bacterial contamination. Therefore, in this study, the validity of equipping DSnB catheters with check valves to prevent retrograde bacterial contamination was examined., Methods: For the in vitro study, excised saline-filled swine bladders were drained using DSnB catheters with or without check valves, and the time required for intravesical pressure to reach 5 cmH 2 O was measured. For the in vivo study, in cross-over experiments comparing DSnB catheters with and without check valves, OCD using DSnB catheters for 10 h was performed in rabbits under analgesia. Bacterial growth from urine samples before and after OCD and residual urine volume were examined., Results: For the in vitro experiment, the median drainage time was 368.2 s (range, 88-1,085 s) and 344.7 s (range, 28-840 s) with and without check valves, respectively (n = 6), which was not significantly different. For the in vivo experiment, in cross-over experiments (n = 8) new bacterial growth rates after OCD did not differ, and median residual urine volume was 17.1 mL (range, 0-75 mL) and 1.2 mL (range, 0-5 mL) with and without check valves, respectively (P = 0.055)., Conclusions: Installing a check valve in the DSnB catheter did not decrease new bacterial growth, while tending to increase residual urine volume. DSnB catheters without check valves appear to be better for continuous drainage of urine from bladder., (© 2019 Japan Pediatric Society.)

Aim: To determine the risk of microbiological contamination with hospital use high- and low-flow bubbling humidifiers., Methods: A systematic literature review was carried out in 6 databases. Observational or experimental studies published between 1990 and 2016 were selected, written in English or Spanish, and in which microbiological contamination with hospital use high- and low-flow bubbling humidifiers was investigated., Results: A total of 12 articles were included: 4 analyzed the water from reusable humidifiers, 4 analyzed the water from prefilled system humidifiers, and the rest compared samples from both models. Microbial contamination was observed in all studies in which reusable humidifiers were evaluated, usually involving common bacteria from the skin flora, while potential pathogenic species were notified in 2 studies. No microbial contamination was isolated from reusable humidifiers, regardless of whether they had been consecutively used over time by a single patient or by several patients., Conclusion: On one hand, there seems to be a low risk of contamination during the first weeks of use of prefilled humidifiers, which allows multiple use in different patients, without a risk of cross-contamination. On the other hand, it should be underscored that handling reusable humidifiers without correct aseptic measures can increase the risk of contamination; replacing reusable humidifiers with prefilled models therefore could be the safest option., (Copyright © 2018 Elsevier España, S.L.U. y SEMICYUC. All rights reserved.)

Prions are proteinaceous infectious agents that are highly resistant to denaturation. Sterilization of prion-contaminated mouse cages requires chemical agents and increased autoclave temperatures that damage traditional cages, thus increasing facility costs. Disposable cages are a possible alternative that might decrease replacement costs without compromising the environment of the mice. We compared our standard protocol of changing traditional cages and bedding once every 2 wk to an experimental protocol using disposable cages in which only the bedding was changed once every 2 wk over an 8-wk period. We hypothesized that disposable cages would retain an acceptable level of cleanliness (measured by ATP swabs and contact plates) for at least 8 wk when bedding is replaced every 14 d. Results from ATP swabs and contact plates showed no difference between the 2 protocols during the 8-wk experiment. Prolonged use (that is, as long as 8 wk) of disposable cages had no additional environmental concerns, compared with traditional cages.

Background and study aims  The preferred management of bleeding esophageal varices includes endoscopic band ligation. Endoscopic ligation devices (ELDs) are expensive and designed for single use, limiting their uptake in developing countries. We aimed to assess the efficacy of reprocessing ELDs using terminal microbial cultures and adenosine triphosphate (ATP) testing. Materials and methods  ELDs were recovered after clinical use and their components (cap, handle, and cord) were subjected to reprocessing. This included manual cleaning, automated high-level disinfection (HLD), and drying with forced air. Using sterile technique, ELD components were sampled for ATP at three stages: before manual cleaning, after manual cleaning, and after HLD. Components were sent to an external laboratory for culturing. Cultures were interpreted as positive upon identification of Gram-negative bacilli. Results  A total of 14 clinically used ELDs were studied, and 189 ATP tests and 41 cultures were evaluated. Overall, 95 % (39/41) of components and 86 % (12/14) of ELDs were culture-negative or did not yield Gram-negative bacilli. Two components (5 %; one handle and one cord) harbored Gram-negative bacilli in quantities of 1 CFU per component. There was no apparent correlation between ATP at any juncture of reprocessing and terminal cultures. Conclusions  Reprocessing of ELDs is effective, resulting in infrequent and minimal microbial contamination. Microbial culturing can be used to ensure adequacy of ELD reprocessing if pursued. Until reusable ELDs are commercially available, continued efforts to better define the adequacy and long-term effects of reprocessing ELDs are needed., Competing Interests: Competing interests: None, (© Georg Thieme Verlag KG Stuttgart · New York.)

BACKGROUND Endoscope-associated infections are reported despite following proper reprocessing methods. Microbiological testing can confirm the adequacy of endoscope reprocessing. Multiple controversies related to the method and interpretation of microbiological testing cultures have arisen that make their routine performance a complex target. OBJECTIVE We conducted a pilot study using disposable bronchoscopes (DBs) to simulate different reprocessing times and soaking times and to compare high-level disinfection versus ethylene oxide sterilization. We also reviewed the time to reprocessing and duration of the procedures. METHODS Bronchoscopes were chosen because an alternative disposable scope is commercially available and because bronchoscopes are more prone to delays in processing. Disposable bronchoscopes were contaminated using a liquid bacterial suspension and were then incubated for 1-4 hours. Standard processing and high-level disinfection were performed on 36 endoscopes. Ethylene oxide sterilization was performed on 21 endoscopes. Endoscope cultures were performed using the standard "brush, flush, brush" technique. RESULTS After brushing was performed, a final water-flush culture procedure was the most effective method of detecting bacterial persistence on the disposable scopes. Klebsiella pneumoniae was the most commonly recovered organism after reprocessing. Ethylene oxide sterilization did not result in total elimination of viable bacteria. CONCLUSION Routine endoscopy cultures may be required to assess the adequacy of endoscopic processing. Infect Control Hosp Epidemiol 2017;38:136-142.

Disposable bronchoscopes such as the Ambu aScope TM 3 are marketed as 'single use' The risks of contamination from prolonged device storage before possible re-use are unknown. Following clinical bronchoscopy in patients whose lungs were mechanically ventilated, 20 aScope TM 3's bronchoscopes received a standard 'social clean' and were then stored. Subsequent paired saline flush and swab samples were taken at time zero, and at 24 h and 48 h. Positive microbiological cultures were obtained from at least one time point from 16 of the 20 bronchoscopes. Pathogens considered at high risk of causing pneumonia were isolated from seven bronchoscopes, with significant quantities from six of them. Our study demonstrates that aScope TM 3's should not be re-used on the same patient, as clinically significant growth of micro-organisms occurs frequently, despite adequate social cleaning. Culture of bronchoscopes themselves may be a potentially useful diagnostic tool in the context of pulmonary infection. Our data make it clear that these devices are single use and not single patient use., (© 2016 The Association of Anaesthetists of Great Britain and Ireland.)

Background: Reutilization of single-use vials containing medical drugs is still under discussion. This practice has been adopted as a standard to avoid drug wastage, particularly in developing countries and in the aftermath of disasters. Some studies have assessed sterility of medications stored in single-use vials after utilization as multiple doses; however, most of these were limited to one single drug, included a low number of samples and did not consider an intermediate transfer step from the vial to a disposable syringe. The purpose of this study was to assess microbial contamination of samples withdrawn over three days from disposable syringes prepared from single-use vials., Methods: A prospective sterility study was conducted. A total of 600 initial samples were prepared from six-hundred 10 mL single-use vials of physiological solution into six-hundred 20 mL disposable syringes. Samples were prepared in three different standard operating rooms, on six different days and by the same operator, using basic sterile technique. All syringes were capped, placed together in a non-sterile steel container, covered with a clean drape and stored in the refrigerator at 4°C under non-sterile conditions. Using basic sterile technique, four samples were withdrawn daily and cultured from each syringe over the next 3 days. Microbial growth was examined on Sabouraud agar and chocolate agar culture media., Results: A total of 7200 samples were collected and 14,400 cultures were performed. No evidence of microbial growth in any of the culture media plates was found., Conclusion: This study demonstrated that contents initially stored in single-use vials and subsequently transferred into disposable syringes in an operating room using sterile technique, maintain sterility after 4 withdrawals per day for a total of 3 days., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: To describe the microbiological findings from bandage contact lenses in patients who work in a hospital environment submitted to photorefractive keratectomy (PRK)., Methods: This prospective comparative case series enrolled 43 eyes of 22 volunteers (28.05 ± 3.50 years). Fourteen individuals (n = 27) were health care professionals who work in health care facilities or community physician's offices. Eight individuals (n = 16) were patients who do not work in hospital environment. Photorefractive keratectomy was performed using standard technique, and a silicone hydrogel bandage contact lens was placed on the cornea and evaluated for adequate fit. Seven days after surgery, the bandage lenses were removed and imprinted in the following culture media: blood agar, chocolate agar, anaerobic-selective agar, and Sabouraud agar. When microbial growth was detected, the microorganism was identified, colony-forming units were quantified, and morphology and Gram-staining properties were analyzed. All isolates were tested for susceptibility to various antibiotics. Significance was assessed by Fisher exact test., Results: Microbial growth was detected in 16.27% of all contact lenses samples. No fungi or anaerobes were found. Microbial growth was only observed in bandage lenses removed from patients who work in hospital environments. Most microorganisms found were sensitive to all antibiotics tested., Conclusion: These results suggest that working in hospital environments increase contamination of the contact lenses after PRK.

Background: Mediastinitis costs hospitals thousands of dollars a year and increases the incidence of patient morbidity and mortality. No studies have been done to evaluate adenosine triphosphate (ATP) counts on disposable and nondisposable electrocardiography (ECG) lead wires in pediatric patients., Objective: To compare the cleanliness of disposable and nondisposable ECG lead wires in postoperative pediatric cardiac surgery patients by measuring the quantity of ATP (in relative luminescence units [RLUs]). ATP levels correlate with microbial cell counts and are used by institutions to assess hospital equipment and cleanliness., Methods: A prospective, randomized trial was initiated with approval from the institutional review board. Verbal consent was obtained from the parents/guardians for each patient. Trained nurses performed ATP swabs on the right and left upper ECG cables on postoperative days 1, 2, and 3., Results: This study enrolled 51 patients. The disposable ECG lead wire ATP count on postoperative day 1 (median, 157 RLUs) was significantly lower (P < .001) than the count for nondisposable ATP lead wires (median, 610 RLUs). On postoperative day 2, the ATP count for the disposable ECG lead wires (median, 200 RLUs) was also lower (P = .06) than the count for the nondisposable ECG lead wires (median, 453 RLUs)., Conclusion: Results of this study support the use of disposable ECG lead wires in postoperative pediatric cardiac surgery patients for at least the first 48 hours as a direct strategy to reduce the ATP counts on ECG lead wires., (©2014 American Association of Critical-Care Nurses.)

Background: The environment is a well-known source of health care-acquired infection. Because of the known risk of contamination, patient privacy curtains require frequent changes to decrease the risk of spread from patients to curtain and visa versa., Methods: Fourteen disposable sporicidal privacy curtains were tested from December 2012 to June 2013 while hanging in a busy intensive care unit. Significant bacterial pathogens were identified and total bacteria enumerated as colony-forming units. Antimicrobial activity of curtain swatches was also tested against a range of bacteria in the laboratory. Measurements were recorded as zone of inhibition and contact inhibition. A cost analysis to replace standard curtains with disposable sporicidal curtains was also undertaken., Results: Cultures grew low numbers of skin and environmental microorganisms with no methicillin-resistant Staphylococcus aureus, carbapenem-resistant Enterobacteriaceae, or Clostridium difficile detected. Vancomycin-resistant enterococci were recovered in very low numbers from 2 curtains where vancomycin-resistant enterococci-infected patients had been located. Privacy curtains demonstrated antimicrobial activity against C difficile and 13 additional bacterial pathogens., Conclusion: We conclude that disposable sporicidal privacy curtains are cost-effective and best replaced at 6 months in a high-risk area such as an intensive care unit., (Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.)

Background and Aim: Endoscopic examinations carry a potential risk of cross-infection, and the traditional reprocessing method is time consuming. We evaluated the safety and efficacy of a novel disposable sheathed gastroscope system in clinical practice in comparison with the conventional gastroscope., Methods: There were two phases in the study. In phase 1, 20 patients with hepatitis B were randomized into two groups: the sheathed group was examined with the novel disposable sheathed gastroscope (n = 10) and the conventional group with the conventional gastroscope (n = 10). Microbiologic tests were performed on each endoscope afterwards. In the second phase, 1120 patients were randomized again into the same two groups with 568 and 552 patients in the sheathed group and the conventional group, respectively. The time duration of the endoscopic procedure and reprocessing were measured. The pathology detection rate of endoscopic examinations, the patients' subjective feelings, and problems occurred during procedures were also recorded., Results: The total instrument turn-around time in the phase 2 sheathed group (9.9 ± 1.3 min) was significantly shorter than the conventional group (39.0 ± 1.4 min, P = 0.000). The mean procedural time was slightly longer in the sheathed group than in the conventional group (4.9 ± 1.4 vs 4.1 ± 1.3 min, P = 0.000). However, the duration of endoscopic reprocessing was much shorter (4.9 ± 0.2 vs 35 ± 0.2 min, P = 0.000). No significant differences were observed in patient discomfort, optical clarity, or pathology detection rate. There were no complications in either group, and no microbial contamination was detected in phase 1 of the study., Conclusions: Compared with the conventional gastroscope, the novel disposable sheathed gastroendoscope is safe and more efficient in clinical practice., (© 2013 Journal of Gastroenterology and Hepatology Foundation and Wiley Publishing Asia Pty Ltd.)

We present a microfabricated paper-based microbial fuel cell (MFC) generating a maximum power of 5.5 μW/cm(2). The MFC features (1) a paper-based proton exchange membrane by infiltrating sulfonated sodium polystyrene sulfonate and (2) micro-fabricated paper chambers by patterning hydrophobic barriers of photoresist. Once inoculum and catholyte were added to the MFC, a current of 74 μA was generated immediately. This paper-based MFC has the advantages of ease of use, low production cost, and high portability. The voltage produced was increased by 1.9 × when two MFC devices were stacked in series, while operating lifetime was significantly enhanced in parallel., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Background: Flexible cystoscopy is used in urological outpatient departments for diagnostic cystoscopy of bladder cancer and requires a high-level disinfection between each patient. The purpose of this study was to make a microbiological post disinfection efficacy assessment of flexible cystoscopes (FC) using disposable sterile endosheaths., Methods: One hundred endosheaths underwent a leak-test for barrier integrity after cystoscopy. Microbiological samples from these cystoscopies were obtained; after removal of the endosheath, and after cleaning the scope with a detergent cloth, rinsing with tap water followed by 70% ethanol disinfection and subsequent drying. The number of colony forming units (cfu) from the samples was counted after 72 hours and then divided in three categories, Clean FC (<5 cfu/sample), Critical FC (5-50 cfu/sample) and High-risk FC (>50 cfu/sample). The result was compared with data of 10 years continuous control sampling recorded in the Copenhagen Clean-Endoscope Quality Control Database (CCQCD) and analyzed with a Chi-square test for homogeneity., Results: All 100 endosheaths passed the leak-test. All samples showed a Clean FC and low means of cfu. A query to the CCQCD, showed that 99.8% (1264/1267) of all FC with a built-in work-channel reprocessed in a WD were clean before use., Conclusion: The reprocessing of FC using endosheaths, as preformed in this study, provides a patient-ready procedure. The results display a reprocessing procedure with low risk of pathogen transmission, high patient safety and a valid alternative to the recommended high-level disinfection procedure of FC. However, the general impression was that sheaths slightly reduced vision and resulted in some patient discomfort.

Erlenmeyer flask or conical flask, usually made of glass, is widely used for laboratory scale suspension culture of microorganism, such as Escherichia Coli and yeast. Due to being non-disposable culture vessel, it has to be cleaned, packaged and sterilized prior to use, which are time, labor and energy consuming work, and has the potential risk of cross-contamination. Despite the rigid plastic conical flasks are possible for single use, they are not economically effective and produce more waste. To overcome these drawbacks, here we successfully developed a novel disposable flexible bioreactor with a plastic film through a thermo-fusion technique. With a triangular pyramid shape, the bioreactor enabled itself to keep a three-dimensional internal space without needing air inflation and well adapted to the commercial available orbital shaker. Unlike the conventional rigid conical flasks and other reported flexible flasks, which had to be fixed in the shaker, the flexible bioreactor could keep sitting on the silicone pad-carpeted platform of the orbital shaker steadily without any fixation needed at the shaking speeds below 250 rpm, thus making it simple to handle. Compared with the traditional conical glass flasks, the innovative flexible bioreactors achieved a significant higher efficiency in bacteria growth and oxygen transfer rates. In conclusion, the novel flexible bioreactor is an ideal disposable culture vessel for microorganism suspension culture at laboratory scale and holds a promising potential to replace the glass flask and rigid plastic flask in the future., (Copyright © 2013. Published by Elsevier B.V.)

It is desirable to maintain a low bacterial count in the operating room air to prevent surgical site infection. This can be achieved by ventilation or by all staff in the operating room wearing clothes made from low-permeable material (i.e. clean air suits). We investigated whether there was a difference in protective efficacy between a single-use clothing system made of polypropylene and a reusable clothing system made of a mixed material (cotton/polyester) by testing both in a dispersal chamber and during surgical procedures. Counts of colony-forming units (cfu)/m(3) air were significantly lower when using the single-use clothing system in both settings., (Copyright © 2013 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.)

Objective: To determine the efficacy of decontamination and sterilization of a disposable port intended for use during single-incision laparoscopy., Sample: 5 material samples obtained from each of 3 laparoscopic surgery ports., Procedures: Ports were assigned to undergo decontamination and ethylene oxide sterilization without bacterial inoculation (negative control port), with bacterial inoculation (Staphylococcus aureus, Escherichia coli, and Mycobacterium fortuitum) and without decontamination and sterilization (positive control port), or with bacterial inoculation followed by decontamination and ethylene oxide sterilization (treated port). Each port underwent testing 5 times; during each time, a sample of the foam portion of each port was obtained and bacteriologic culture testing was performed. Bacteriologic culture scores were determined for each port sample., Results: None of the treated port samples had positive bacteriologic culture results. All 5 positive control port samples had positive bacteriologic culture results. One negative control port sample had positive bacteriologic culture results; a spore-forming Bacillus sp organism was cultured from that port sample, which was thought to be an environmental contaminant. Bacteriologic culture scores for the treated port samples were significantly lower than those for the positive control port samples. Bacteriologic culture scores for the treated port samples were not significantly different from those for negative control port samples., Conclusions and Clinical Relevance: Results of this study indicated standard procedures for decontamination and sterilization of a single-use port intended for use during singleincision laparoscopic surgery were effective for elimination of inoculated bacteria. Reuse of this port may be safe for laparoscopic surgery of animals.

Purpose: To compare the locations and types of bacterial contamination of bandage disposable soft contact lenses after laser subepithelial keratectomy (LASEK) and photorefractive keratectomy (PRK)., Methods: Bandage disposable soft contact lenses were collected with sterile forceps from 30 eyes of 15 consecutive patients treated with LASEK (LASEK group) and 30 eyes of 15 consecutive patients who underwent PRK (PRK group) to correct myopia. Immediately after collection, each lens was cut in two parts with sterile scissors and placed onto chocolate agar with one piece outer face down and the inner face down for the other piece. The lenses were analyzed for bacterial colonization and evaluated for the amount of growth on the inner face and outer face, respectively. The antibiotic susceptibility tests were performed for the isolates using disk diffusion., Results: Five positive cultures (16.7%) were found in LASEK group: 4 appeared in the inner face of the lens and1 appeared in the outer face. In PRK group, 2 of the 30 contact lenses (6.67%) had positive cultures; both of them appeared in the outer face of the lens. The difference of positive culture rate in the two groups was not statistically significant (χ=1.46, P=0.228). When comparing the positive colonization rate in location, the positive culture rate in the inner face of LASEK group was statistically significantly higher than that of PRK group (13.3% vs. 0%, χ=4.29, P=0.038); however, no clinical finding of infection was noted. In both groups, methicillin-sensitive coagulase-negative staphylococci (MSSCoN) were the most common isolate. Besides MSSCoN, the growth of methicillin-resistant coagulase-negative staphylococci, Corynebacterium, and Micrococcus were also present in this study. All the microorganisms were sensitive to tobramycin, which was used in conjunction with dexamethasone to treat the cases., Conclusions: Previous literature reports that the risk of infectious keratitis after LASEK or PRK is relatively low. However, within this study, the rate of positive cultures was relatively higher in LASEK group (16.7%) compared with that of PRK group (6.67%), especially in the inner face of the lens. The reason may be related to the procedure of keeping the epithelial flap in place, which could develop a local environment suitable for bacterial colonization and potential infection. Coagulase-negative staphylococci, a major element of the natural conjunctival flora, remain a major potentially infectious agent after LASEK and PRK.

Introduction: Cotton as well as synthetic textile medical products are widely used as barrier materials and individual protection against displacement of biological infectious factors. The required level of protection of these products for multiple use and disposable multilayer laminates against the penetration of microbes depends on the risk connected with type of surgical procedure defined in normative documents. METHODS. Cotton and syntetic medical textiles for multiple use, 30-times subjected to processes simulating conditions of the use as well as disposable multilayer surgical drapes were tested. Resistance to microbial wet penetration was conducted according to the PN-EN ISO 22610: 2007 standard., Results: The barrier of cotton fabrics was reduced after first washing and then systematically grew after each often cycles to the value close to the value at the beginning. From the twentieth cycle of simulated conditions of the use, barrier index was reduced. The barrier of the synthetic textile stayed on the average level, while multilayer disposable products ensured the full impermeability for the bacteria., Conclusions: Natural cotton textiles for multiple use could be apply on operative blocks in limited range because of the changes of the cotton structure caused by repeated laundering process and sterilization. Synthetic materials also have limited application, although are more resistant to cleaning and sterilization processes. Disposable synthetic laminates with many layers use guarantee impermeability for bacteria and may be applied in operative blocks without restrictions.

Objectives: To evaluate neutrophil-enhanced Pseudomonas aeruginosa (PA) biofilm formation on silicone hydrogel contact lenses and to determine the effect of epithelial biodebris on PA adherence in contact lens storage cases., Methods: A fully invasive PA corneal isolate stably conjugated to green fluorescent protein was used. Unworn lotrafilcon A contact lenses were incubated at various ratios of PA to polymorphonuclear neutrophil (PMN) for 24 hours at 37°C. Lens-associated PA was evaluated using laser scanning confocal microscopy and nonviable PA were visualized using propidium iodide. Viable bacteria were enumerated by colony-forming unit (CFU) analysis. For acute epithelial cell studies, PA viability was determined after coincubation with freeze-thaw epithelial cell lysates in 96-well polystyrene plates. Levels of residual cellular debris and bacterial viability were further assessed in used contact lens storage cases., Results: Laser scanning confocal microscopy demonstrated that cotreatment with PMA-stimulated neutrophils increased PA adherence over 24 hours to lens surfaces with a striking alteration of PA architecture. Propidium iodide staining showed that the adherent bacteria consisted of a mixture of viable and nonviable PA; a PMN-associated increase in viable PA was confirmed by CFU (PA:PMN 0.1:1, P = 0.025; PA:PMN 1:1, P = 0.005). Acute epithelial cell debris studies revealed a significant increase in viable PA in 96-well plates in the presence of epithelial freeze-thaw lysates (PA:debris 1:1, P = 0.002; PA:debris 100:1, P = 0.002). Crystal violet staining of used lens storage cases revealed residual cellular debris at all time points, which was independent of microbial contamination; all lens cases used for periods of 9 months or more were uniformly associated with high levels of viable microorganisms., Conclusion: These results demonstrate that prolonged corneal inflammation with the presence of PMNs when confronted with simultaneous PA challenge in extended contact lens wear has the potential to stimulate biofilm formation on silicone hydrogel contact lenses. These findings further suggest that a persistent buildup of extracellular debris in lens storage cases may contribute to the heavy biofilms reported on these surfaces.

Fluid therapy is an integral component of standard supportive care in veterinary medicine and is often given subcutaneously for ease of administration. Multiple animals may be treated by using the same bag. These bags often are used repeatedly until they are empty or until a time specified by an IACUC or similar advisory group. This practice introduces the risk of contamination. Here we assessed the sterility of multiple-use fluid bags in the laboratory setting for a maximum of 60 d. Bags were manipulated to mimic infrequent and frequent use. Bacterial cultures of fluid and bag wall and assays for endotoxin and ATP activity were negative at all time points through 30 d. Two fluid samples yielded bacterial growth at 60 d, although all other tests were negative. These results suggest that fluid bags used chronically can be maintained in a sterile condition for a maximum of 30 d.

Background: A gap between the bottom of gowns and the top of gumboots (commonly known as wellingtons or rubber boots outside of New Zealand) makes it possible for blood splashes to enter surgeons' gumboots and contact skin, putting them at risk of exposure to HBV, HCV and HIV. This study investigated the prevalence of blood splashes inside gumboots used by surgical staff at a single hospital., Method: Ninety-four pairs of gumboots (91 from male surgeons, 3 from female surgeons) from the hospital operating theatres were used in this study. Each pair of boots was visually inspected for internal contamination with blood. Possible stains were checked using urine dipsticks to confirm the presence of blood., Results: Of the 94 pairs of gumboots checked, 55 pairs (58.5%) had blood staining on the inside lining. Eighty percent of blood stains were larger than 20 mm². None of the female surgeons' gumboots were contaminated compared to 60% of the males' pairs., Cocnlusion: A large proportion of the gumboots used in operating theatres were contaminated internally with blood. The results of this study suggest that longer gowns should be available to health care workers in operating theatres to reduce internal contamination of gumboots and minimise the chance of exposure to body fluids.

Hospital-acquired infections caused by antibacterial-resistant microorganisms are associated with high mortality and morbidity rates and markedly affect hospital economics. The expense became greater in 2008 when reimbursement for treatment of hospital-acquired infections was no longer provided by Medicare. Infections caused by cross-contamination with resistant bacteria can be eliminated by 3 methods: kill the bacteria before resistance develops, stop bacteria from communicating and acquiring resistance, and eliminate the pathway from one patient to another. Because electrocardiography wires cannot be completely disinfected 100% of the time, they may be contributing to the growth of resistant bacteria. The many pathways provided by reusable wires for cross-contamination with resistant bacteria increase the risk for hospital-acquired infection when these wires are used. Disposable electrocardiography leads eliminate risk of infection through these pathways. Adoption of disposable electrocardiography leads as an adjunct to an overall infection control program can decrease infection rates in acute health care facilities.

We assessed the effect of a double concentration of supplemental polymyxin B, amphotericin B, nalidixic acid, trimethoprim and azlocillin (PANTA) added to the Mycobacterial Growth Indicator Tube (MGIT) on contamination and positivity rates in 216 sputum cultures. Contamination rates were respectively 12.9% and 5.5% for samples processed using standard and double PANTA concentrations (P = 0.0001, McNemar's test). Thirty-five per cent of cultures performed using standard PANTA and 36.5% of those performed using two-fold PANTA concentrations were positive for Mycobacterium tuberculosis, compared to 25.9% of cultures inoculated on Ogawa medium. These results suggest that the use of MGIT with 2× PANTA may be useful in reducing culture contamination without reducing the diagnostic yield.

Background: Reprocessing of single-use medical instruments has been proposed as a mechanism for managing the rising costs of health care. We compared the performance of new and reprocessed laparoscopic trocars., Study Design: New and reprocessed laparoscopic trocars were evaluated. Testing consisted of visual and microscopic inspection, force of trocar insertion and removal through a porcine abdominal wall, trocar seal leak rate determination, and testing of blade shield speed., Results: Three hundred twenty-eight reprocessed trocars and 199 new trocars were evaluated. Trocars undergoing force testing were inspected for imperfections. In this group, 28.2% of reprocessed and 3.79% of new trocars manifested some gross or microscopic imperfections (p = 0.063). D12LT trocars (Ethicon) required more force with insertion with reprocessed compared with new trocars (0.021). D5LT (Ethicon) new trocars required more force to remove than reprocessed trocars (p = 0.004). Both the shield cover time and the shield response time were found to be faster in the reprocessed (p = 0.0001) compared with the new trocars. Leak testing performed with probes (4.7 mm and 12.9 mm) in place demonstrated a significantly greater amount of leakage for the reprocessed trocars compared with the new trocars, both before and after insertion of the right-angled instrument (p = 0.0001)., Conclusions: When comparing new and reprocessed trocars, there are significant differences in visual trocar defects, insertion and extraction forces, shield response times, and trocar leak rates for some of the device comparisons. The clinical significance of these changes should be weighed against cost savings and environmental impact. Additional testing is necessary for a better understanding of the impact of trocar reprocessing., (Copyright © 2010 American College of Surgeons. Published by Elsevier Inc. All rights reserved.)

Purpose: To elucidate the reservoirs of Pseudomonas aeruginosa keratitis associated with contact lens (CL) wear by using a molecular genotyping method., Method: Ten P. aeruginosa isolates obtained from two young adult patients with infectious keratitis associated with CL wear were studied. These were isolated from corneal specimens, conjunctival swabs, discharges, CL storage cases, and the living environment of the two patients. Species identification was performed with an Oxi/Ferm Tube II system using well-separated colonies on MacConkey and NAC agar plates. We employed molecular genotyping by pulsed-field gel electrophoresis., Results: We isolated three (one each from a corneal scraping, discharge, and a CL storage case) P. aeruginosa samples from patient 1, and seven (one each from the conjunctival swab, CL storage case, and the patient's fingers, and four from the patient's room) from patient 2. Pseudomonas aeruginosa of environmental origin could not be obtained from the house of patient 1. The genotypes of two P. aeruginosa isolates, from corneal scraping and discharge, were identical to that of the isolate from the CL storage case belonging to patient 1. In patient 2, the isolates from the eye and the CL storage case showed the identical genotype, which was different from those of the environmental isolates., Conclusion: Our results suggest that the causative P. aeruginosa strains in cases of infectious keratitis associated with CL wear originate in contaminated CL storage cases. However, it is still unclear whether the environmental strains in the patients' houses also cause keratitis.

Objectives: To estimate the rate of corneal erosion coupled with gram-negative bacterial contamination of contact lenses and compare this with the rate of microbial keratitis (MK) with contact lenses., Methods: The rate of corneal erosion and contact lens contamination by gram-negative bacteria were calculated from several prospective trials. These rates were used to calculate the theoretical rate of corneal erosion happening at the same time as wearing a contact lens contaminated with gram-negative bacteria. This theoretical rate was then compared with the rates of MK reported in various epidemiological and clinical trials., Results: Corneal erosions were more frequent during extended wear (0.6-2.6% of visits) compared with daily wear (0.01-0.05% of visits). No corneal erosions were observed for lenses worn on a daily disposable basis. Contamination rates for lenses worn on a daily disposable basis were the lowest (2.4%), whereas they were the highest for low Dk lenses worn on an extended wear basis (7.1%). The estimated rate of corneal erosions occurring at the same time as wearing lenses contaminated with gram-negative bacteria was the lowest during daily wear of low Dk lenses (1.56/10,000 [95% CI: 0.23-10.57]) and the highest during extended wear of high Dk lenses (38.55/10,000 [95% CI: 24.77-60.04]). These rates were similar in magnitude to the rates reported for MK of different hydrogel lenses worn on differing wear schedules., Conclusion: The coincidence of corneal erosions during lens wear with gram-negative bacterial contamination of lenses may account for the relative incidence of MK during lens wear with different lens materials and modes of use.

Background and Objectives: In October 2008, an investigation was conducted into a cluster of gram-negative bloodstream infections after invasive pain management procedures at an outpatient facility to identify additional cases and determine the source of illness., Methods: We conducted a retrospective cohort study to determine exposures associated with illness. Eligible patients had an invasive procedure in the 4 days before or after the procedure date of the initial case-patients. Infection control assessments were made, and environmental specimens collected., Results: Four laboratory-confirmed case-patients (3 with Klebsiella pneumoniae and 1 with Enterobacter aerogenes) and 5 suspect case-patients were identified. In addition to the 9 confirmed and suspect case-patients, 45 patients were interviewed. All confirmed and suspect case-patients had a sacroiliac joint steroid injection procedure; injection into the sacroiliac joint was associated with illness (9/22 versus 0/31; P < 0.0001). Multiple breaches in infection control were noted including the reuse of single-use vials for multiple patients. The 3 K. pneumoniae with positive blood cultures were indistinguishable by pulse-field gel electrophoresis, and the E. aerogenes-positive blood culture was indistinguishable by pulse-field gel electrophoresis to the culture from an open vial of 100-mL iodixanol contrast solution., Conclusion: Infection was associated with pain management procedures, specifically those involving injection to the sacroiliac joint. Lapses in infection control likely led to the contamination of single-use vials that were then used for multiple patients. Reuse of medication vials should be restricted, and affordable single-dose vials should be made available.

Background: Instilling eye drops is a ubiquitous procedure in eye clinics. This audit aimed to assess the risk of contamination of disposable droppers and to quantify the financial and waste implications of reducing this risk to zero by using disposable droppers only once., Methods: A total of 100 disposable Minims were used to place one drop in each eye of 70 patients. The dropper tip was then cultured for aerobic and anaerobic microbes., Results: Coagulase-negative staphylococcus was cultured from five samples. The contamination rate per drop application was 2.5%. The risk of cross-contamination with coagulase-negative staphylococcus would be between 1 : 400 and 1 : 80 if the bottle was reused once or six times. Reducing this risk to zero costs between pound2.75 and pound4.6 million per annum and generates between 6.85 and 11.42 more tonnes of paper waste and between 12.69 and 21.15 more tonnes of plastic waste than a strategy that reuses the disposable dropper., Conclusion: Reducing the risk of dropper contamination and subsequent cross infection has financial and environmental costs. As exposure to coagulase-negative staphylococcus is not necessarily associated with infection, it would be useful to decide acceptable risk levels for a given cost to maximise both cost-effectiveness and patient safety.

Aims: The instillation of a combined fluorescein-anaesthetic eye drop is common practice in most ophthalmology clinics. Chauvin Pharmaceuticals produce unpreserved proxymethacaine 0.5% and fluorescein 0.25% in a Minims vial (PFM) intended for single application only. Our aim was to determine whether the reuse of these eye drops for multiple applications has the potential for bacterial transmission., Methods: Samples were collected from doctors in general outpatient clinics. Each sample constituted a blood agar plate inoculated with the initial drop of fluid from a PFM as a control. The vial was then used for multiple applications on consecutive patients. One of the last remaining drops was then inoculated onto an alternate marked site on the same plate to serve as the test sample. The samples were immediately transported to the Microbiology laboratory and incubated at 37 degrees C for 48 h. The results were interpreted thereafter by a Microbiologist., Results: A total of 41 samples were collected by eight Samplers. In all, 7/41(17%) samples showed growth of normal conjunctiva and lid flora on the test area. These were coagulase negative Staphylococci and Corynebacterium spp., Conclusions: The reuse of single application of PFM should be questioned due to the potential risk of transmitting pathogens. A change to a single use only policy would result in a projected threefold increase in the annual budget for these drops.

Background: Conventional reprocessing of endoscopes with high-level disinfection is labor intensive, expensive, delays the turnover of instruments, and involves potential exposure of personnel to toxic chemicals. We report a prospective clinical trial with rigorous microbiologic assessment of a novel disposable, sterile, polyurethane sheath, which can be easily and snugly applied over a nasopharyngoscope before performing the endoscopic procedure, with enzymatic cleansing and disinfection of the instrument with 70% ethanol following the procedure to determine whether the use of the novel sheath can provide reliable protection against bacterial contamination and obviate the need for routine high-level disinfection in reprocessing., Methods: Baseline cultures were obtained at 3 time periods from the control heads and insertion shafts of nasopharyngoscopes used in 100 clinical examinations: before application of the protective sheath and execution of the procedure; immediately after the procedure and removal of the sheath; and after enzymatic cleaning, disinfection with 70% ethanol, and drying. All 100 used sheaths and 20 unused sheaths were subjected to high-pressure leak testing to assess barrier integrity., Results: Bacteria were detected on 16 control heads and 6 shafts prior to the procedure; from 13 heads and 1 shaft immediately following the nasopharyngoscopic procedure and sterile sheath removal; and none of the instruments following cleaning, ethanol disinfection, and drying. No sheath showed loss of barrier integrity on leak testing., Conclusion: Use of a high-quality, snugly fitting, sterile, disposable polyurethane sheath on a nasopharyngoscope during a clinical examination, combined with enzymatic detergent cleaning and disinfection with 70% ethanol, can provide a reliably decontaminated, patient-ready instrument, eliminating the need for high-level disinfection of endoscopes.

Ventilator-associated pneumonia is the most common nosocomial infection in the intensive care unit, and it is associated with prolonged hospitalization, increased health care costs, and high attributable mortality. During the past several decades, numerous studies focused on the crucial role of the endotracheal tube (ETT) in the pathogenesis of ventilator-associated pneumonia. Tracheal intubation thwarts the cough reflex, compromises mucocilliary clearance, injures the tracheal epithelial surface, provides a direct conduit for rapid access of bacteria from upper into the lower respiratory tract, and allows the formation of biofilm on the ETT surface. The combination of these factors puts the mechanically ventilated patient at great jeopardy of developing ventilator-associated pneumonia. Many preventive strategies have arisen from this understanding: control of intracuff pressure, aspiration of subglottic secretions, decontamination of subglottic area, use of antiseptic impregnated ETTs, and elimination or prevention of the ETT biofilm formation. The authors review the role of ETT management for the prevention of the ventilator-associated pneumonia.

Various guidelines have been proposed regarding which portions of a surgical gown may be considered sterile. Unfortunately, the validity of these recommendations has not been definitively established. We therefore evaluated gown sterility after major spinal surgery to assess the legitimacy of these guidelines. We used sterile culture swabs to obtain samples of gown fronts at 6-inch increments and at the elbow creases of 50 gowns at the end of 29 spinal operations. Another 50 gowns were swabbed immediately after they were applied to serve as negative controls. Bacterial growth was assessed using semiquantitative plating techniques on a nonselective, broad-spectrum media. Contamination was observed at all locations of the gown with rates ranging from 6% to 48%. Compared with the negative controls, the contamination rates were greater at levels 24 inches or less and 48 inches or more relative to the ground and at the elbow creases. The section between the chest and operative field had the lowest contamination rates. Based on these results, we consider the region between the chest and operative field to be the most sterile and any contact with the gown outside this area, including the elbow creases, should be avoided to reduce the risk of infection.

Objectives: Disposable soft contact lenses that are commonly used after laser refractive surgery are known to be colonized by bacteria and play a key role in Bacterial Keraitis (BK) pathogenesis. Coagulase-negative staphylococci (CoNS) have been found to be the most common pathogen involved in this postoperative infection. In this study a rapid and a simple assay was developed for studying attachment and accumulation of CoNS on soft contact lenses in vitro using [3H] thymidine., Methods: Thirty-five isolates of CoNS were obtained from 27 laser refractive surgery patients. Twenty-five of these thirty-five CoNS were isolated in multiple cultures. Ten CoNS were isolated in cultures from patients who underwent reoperation. The assay was optimized using a biofilm-producing strain, S. epidermidis RP62A, which was subcultured overnight at 37 degrees C on blood agar medium. Quantitative determination of biofilm production was tested. Presence of the genes icaADB and icaD was determined in all isolates. All isolates were biochemically analyzed using the Phene Plate (PhP) system modified for typing of CoNS. The CoNS isolates were further characterized to species level using ID32Staph.Mann-Whitney rank sum test and chi-square test were used to identify statistical differences in adherence, index, antibiotic susceptibility patterns, and biofilm production or presence of the ica operon between clinically significant isolates and non-postoperative BK isolates., Results: No differences in attachment and accumulation were found between isolates causing BK after laser refractive surgery and contaminant isolates. In addition, there were no differences in the distribution of the ica operon between the two groups, as determined by polymerase chain reaction. Nevertheless, the ability to produce biofilm was found to be present significantly more frequently among BK isolates than among non-postoperative BK isolates., Conclusions: This study shows that the method using radioactive thymidine to analyze adherence of CoNS to soft contact lenses enables detection of differences in the adherence patterns of individual isolates.

Nanostructured materials with various methods of coating have antimicrobial activity and can be used in creation of biologically active systems with a given medical-biological characteristics. Use of organic derivatives of fullerene S60 as a new class of biologically active compounds and their use is a new and promising direction in this area, providing a selective effect on the micro-organisms of different species. Using probes with the biologically active nanostructured surfaces useful for the correction of pH-dependent states, such as the translocation of microflora in the intestine when postgastrectomical states may have to correct with GERD. Programmable output regulators of activity of intestinal microbiota can be viewed as a way of normalizing the digestive-transport processes in the intestine.

Purpose: To evaluate the extent and agents of bacterial contamination of bandage disposable soft contact lenses after laser subepithelial keratectomy (LASEK) and to correlate the findings with clinical data., Methods: Disposable soft contact lenses were collected from 52 eyes of 26 consecutive patients treated with LASEK for myopia. The patients were treated with a fixed combination of tobramycin and diclofenac until epithelial closure. The lenses were removed on the fourth or fifth postoperative day with sterile forceps and immediately placed in sterile tubes containing culture media brain-heart infusion broth. The lenses were evaluated for microbial colonization., Results: Of the 52 contact lenses analyzed, six (11.5%) had positive cultures. However, no clinical finding of infection was noted. Isolated microorganisms were coagulase-negative staphylococci (two lenses), Stenotrophomonas maltophilia (two lenses), Acinetobacter species (one lens), and Aeromonas hydrophila (one lens). Except for one case, the microorganisms were sensitive to the administered antibiotic., Conclusions: The risk of infectious keratitis after LASEK seems to be low. Except for staphylococci, the isolated microorganisms have not been previously reported to colonize the ocular surface or cause keratitis after refractive surgery. These findings may suggest a changing trend of potentially infectious agents after surface ablation.