Selective photoantisepsis.

BACKGROUND AND OBJECTIVE: Selective killing of pathogens by laser is possible due to the difference in absorption of photon energy by pathogens and host tissues. The optical properties of pathogenic microorganisms are used along with the known optical properties of soft tissues in calculations of the laser-induced thermal response of pathogen colonies embedded in a tissue model. The objective is to define the laser parameters that optimize pathogen destruction and depth of the bactericidal effect. MATERIALS AND METHODS: The virtual periodontium is a computational model of the optical and time-dependent thermal properties of infected periodontal tissues. The model simulates the periodontal procedure: Laser Sulcular Debridement.1 Virtual pathogen colonies are placed at different depths in the virtual periodontium to determine the depth for effective bactericidal effects given various laser parameters (wavelength, peak power, pulse duration, scan rate, fluence rate) and differences in pathogen sensitivities. RESULTS: Accumulated background heat from multiple passes increases the depth of the bactericidal effect. In visible and near-IR wavelengths the large difference in absorption between normal soft tissue and Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi) results in selective destruction. Diode laser (810 nm) efficacy and depth of the bactericidal effect are variable and dependent on hemin availability. Both pulsed-Nd:YAG and the 810 nm diode lasers achieve a 2-3 mm deep damage zone for pigmented Pg and Pi in soft tissue without surface damage (selective photoantisepsis). The model predicts no selectivity for the Er:YAG laser (2,940 nm). Depth of the bactericidal effect is highly dependent on pathogen absorption coefficient. Highly sensitive pathogens may be destroyed as deep as 5-6 mm in soft tissue. Short pulse durations enable confinement of the thermal event to the target. Temporal selectivity is achieved by adjusting pulse duration based on target size. CONCLUSION: The scatter-limited phototherapy model of the infected periodontium is applied to develop a proper dosimetry for selective photoantisepsis. Dosimetry planning is essential to the development of a new treatment modality. Lasers Surg. Med. 48:763-773, 2016. © 2016 Wiley Periodicals, Inc.

Cuidados del cordón umbilical en el recién nacido: revisión de la evidencia científica / Umbilical Cord Care Procedures in the Newborn: A Systematic Review

Objetivos: En este trabajo se realiza una revisión de la evidencia científica sobre las pautas de cuidado de la herida umbilical del recién nacido recomendadas en la actualidad con el objetivo de determinar cuál es el mejor cuidado posible. Metodología: En mayo de 2015 se realizó una revisión, siguiendo los criterios PRISMA, de la literatura científica que se completó con una revisión manual. La herramienta utilizada para la evaluación de los trabajos seleccionados fueron las «Fichas de Lectura Crítica» de OSTEBA del Servicio de Evaluación de Tecnologías Sanitarias del Gobierno Vasco. Resultados: Incluimos en la revisión 9 artículos, de los cuales 5 son revisiones previas y 4 ensayos clínicos aleatorizados y controlados. La mayoría de los trabajos comparan la utilización de un antiséptico para la cura del ombligo (generalmente clorhexidina) frente al cuidado seco de la herida. Conclusiones: De acuerdo a la evidencia científica resumida en esta revisión sobre las recomendaciones para la cura del ombligo del recién nacido el método a recomendar será diferente según el país en el que nos encontremos ya sea desarrollado o en vías de desarrollo

Objectives: This paper presents a review of the scientific evidence about the recommended care for newborn umbilical wound in order to establish the best care possible. Methodology: The search was conducted in May 2015, following the PRISMA criteria of scientific literature searches and completed with a manual review. We used the tool «Critical Reading Sheets» of OSTEBA Service for Health Technology Assessment of the Basque Government for the scientific evaluation of the selected works. Results: We included 9 articles in this s review: 5 of them were previous revisions and 4 randomized controlled clinical trials. Most of them compared the use of an antiseptic (mainly clorhexidine) versus dry care. Conclusions: Accordingly to the scientific evidence summarized In this manuscript about the care of newborn’s umbilical cord, the method to recommend will differ depending on whether we are in a developed country or in a developing one

Fundamentos de antisepsia, desinfección y esterilización / Principles of antisepsis, disinfection and sterilization

Este artículo pretende realizar una breve revisión de los principales conceptos en los que se basan las medidas de prevención y control de la infección. La antisepsia comprende el conjunto de técnicas destinadas a la eliminación total (esterilización) o mayoritaria (desinfección) de los gérmenes que contaminan un medio. Ambos procedimientos deben ir precedidos de una limpieza del medio donde se vayan a aplicar. La desinfección se lleva a cabo por medio de biocidas o germicidas, sustancias químicas antimicrobianas cuyos mecanismos de acción y resistencia son muy similares a los de los antibióticos. Esta similitud está generando inquietud por la posibilidad de cruce de información genética que agrave el problema de las resistencias bacterianas. La mayoría de los biocidas pueden actuar como antisépticos, aplicados sobre piel y tejidos, o desinfectantes, sobre materiales inanimados. El espectro de acción de los germicidas depende de las características propias del producto y de factores externos controlables: temperatura, concentración, tiempo de exposición, etc. Las técnicas de esterilización son fundamentalmente de carácter físico, a través de autoclaves que exponen el material a vapor o gas esterilizante. Los mayores avances están en las exposiciones a bajas temperaturas con tiempos más cortos de exposición, en paralelo con los avances tecnológicos de instrumentación con materiales que no soportan temperaturas elevadas y con rotaciones de uso altas, por la presión asistencial

This article aims to provide a brief review of the main concepts on which the prevention and control of infection are based. Antisepsis comprises a set of techniques aimed at the total sterilization, or at most, disinfection, removing germs that contaminate an environment. Both procedures must be preceded by an environmental cleanup in the location in which they intend to be applied. The disinfection is carried out using biocides or germicides. Antimicrobial chemicals, that have mechanisms of action and resistances very similar to antibiotics, are generating concern due to the possibility of crossing genetic information that aggravates the problem of bacterial resistance. Most biocides can act as antiseptics, and applied to skin tissue, or disinfectants on inanimate materials. The spectrum of action of germicides depends on the product itself and external controllable factors: temperature, concentration, exposure time, etc. Sterilization techniques are primarily physical, by exposing the material to steam, or sterilizing gas, using autoclaves. Major advances are the use of low temperatures with shorter exposure times, in parallel with technological advances in instrumentation in order to avoid high temperatures and high use rotations due to workload

Low-temperature plasma--a prospective microbicidal tool.

The effects of low-temperature plasma treatment on microorganisms typically related to skin diseases are studied qualitatively by the inhibition of growth and viability assays to evaluate the potential for classifying as a prospective antiseptic agent. A variety of microorganisms enveloping gram- negative and gram-positive bacteria as well as one genus of yeast and fungus each were exposed to plasma in vitro. In a comparative approach, two power supplies, both of which produce high voltage pulses yet at different temporal characteristics, are applied for the growth study. While operation with both devices led to growth inhibition of all microbes, the results indicate a superior antimicrobial efficacy for high voltage pulse lengths in the nanosecond scale. Fluorescence assays reveal the efficacy of nanosecond-pulse driven plasma in reducing germ viability. Furthermore, the technical background for patents related to low-temperature plasma technology in the field of plasma medicine is discussed.

[Prospects for the use of low-temperature gas plasma as an antimicrobial agent].

Results of application of LTP at atmospheric pressure as an antibacterial agent during the last decade are considered with reference to physicochemical mechanisms of its bactericidal action. The principles of designing modern LTP sources are described in conjunction with the results of LTP application against pathogenic bacteria in vitro and in biofilms. The possibility to destroy biofilm matrix by LTP is estimated along with the results of its testing for the treatment of acute and chronic wound surfaces. Prospects for the development of "plasma medicine" in this country and abroad are discussed with special emphasis on its advantages, such as the absence of long-acting toxic compounds, small probability of spontaneous mutations accounting for resistance to LTP, relatively low cost of LTP sources, independence of LTP effect of the surface relief, painless application.

Prevención de la infección de localización quirúrgica, según un bundle modificado / Prevention of surgical site infection using a modified bundle

Para controlar la infección de localización quirúrgica (IL) se han descrito, además de otras medidas habituales (esterilización de instrumental, atuendo quirúrgico, limpieza de superficies, filtros HEPA, correcta técnica quirúrgica, etc.), unas medidas sencillas, basadas en evidencia tipo i, que además actúan sinérgicamente (bundle): corte del vello con maquinilla en lugar de rasurado, profilaxis antibiótica, control de la glucemia y la temperatura del enfermo intraquirófano. A estas medidas del bundle habría que añadir otra: antisepsia del campo quirúrgico, en el enfermo, y de las manos-antebrazos, en el equipo quirúrgico. En los últimos años se están introduciendo soluciones alcohólicas en lugar de clorhexidina o povidona iodada para la antisepsia del equipo quirúrgico, con muy buenos resultados, y recientemente (enero, 2010) se ha demostrado con un ensayo clínico multicéntrico que la clorhexidina al 2% en alcohol puede reducir a la mitad la ILQ, respecto de la utilización de povidona yodada. Por todo ello, creo que debemos implementar estos cambios de conducta para lograr reducir, sin apenas coste, la ILQ (AU)

Besides the usual measures to control surgical site infection (SSI) (instrument sterilisation, surgical wear, clean surfaces, HEPA filters, and correct surgical technique, etc), there are some simple measures, based on type I evidence which also work synergically (bundle): hair cutting with a machine instead of a razor, antibiotic prophylaxis, blood glucose monitoring and patient temperature during surgery. To this bundle of measures should be added another: antisepsis of the surgical field, on the patient and on hands and forearms, and surgical equipment. In the last few years alcohol solutions have been introduced in place of chlorhexidine and povidone iodide for antisepsis of surgical equipment, with very good results, and in a recent multicentre clinical trial (January, 2010) it was shown that 2% chlorhexidine in alcohol could reduce SSI by half compared to the use of povidone iodide. For these reasons, I believe that we should introduce these behavioural changes to reduce SSI, with a minimum of cost (AU)

Comparison of bacterial counts in glove juice of surgeons wearing smooth band rings versus those without rings.

BACKGROUND: Removal of rings is recommended before surgeons aseptically prepare for surgical procedures. OBJECTIVES: This study was undertaken to determine whether there is a difference between bacterial counts under surgical gloves of ring wearers compared with nonring wearers after proper aseptic hand preparation and 3 hours of wear. METHODS: Twenty volunteer veterinary medical students were divided into 2 groups: One group wore a smooth ring band (without projections or mounted stones) on their ring finger, and the other group did not wear a ring. A modified glove juice method was used to obtain bacterial counts (colony-forming units/mL) inside surgically gloved hands prior to a proper aseptic hand preparation and 3 hours after hand preparation and wear. Each of the pre- and postsurgical glove juice samples were inoculated onto Letheen agar plates, which were incubated aerobically under atmospheric conditions for 48 hours at 35 degrees C. Gloves were tested for perforations using a water pressure test. RESULTS: No differences, or significant change, in bacterial counts were found before or after surgery between all ring hands and nonring hands or between ring and nonring hands for ringed participants. No differences in bacterial counts were found within perforated versus nonperforated gloves. CONCLUSION: There is no compelling evidence to suggest that surgeons wearing rings possess higher bacterial counts under their gloves during surgery.

Are antiseptic-coated central venous catheters effective in a real-world setting?

BACKGROUND: Catheter-related bloodstream infections are common, costly, and morbid. Randomized controlled trials indicate that antiseptic-coated central venous catheters reduce infection rates. OBJECTIVE: To assess the clinical and economic effectiveness of antiseptic-coated catheters for critically ill patients in a real-world setting. METHODS: Central venous catheters coated with chlorhexidine/silver-sulfadiazene were introduced in all patients requiring central venous access in adult intensive care units at the University of Michigan Health System, a large, tertiary care teaching hospital. A pretest-posttest cohort design measured the primary outcome of catheter-related bloodstream infection rate, comparing the 2 years prior to the intervention with the 2 years following the intervention. We also evaluated cost-effectiveness and changes in vancomycin use. RESULTS: The intervention was associated with a 4% per month relative reduction in the incidence of catheter-related bloodstream infection, after controlling for the effects of time. Overall, a 35% relative risk reduction (P < .0003) in the catheter-related bloodstream infection rate occurred in the posttest phase. The use of antiseptic-coated catheters reduced costs more than $100,000 annually. Vancomycin use was less in units in which antiseptic catheters were used compared with wards in which these catheters were not used. CONCLUSION: Antiseptic-coated catheters appear to be clinically effective and economically efficient in a real-world setting.

Disposable surgical face masks: a systematic review.

UNLABELLED: Surgical face masks were originally developed to contain and filter droplets of microorganisms expelled from the mouth and nasopharynx of healthcare workers during surgery, thereby providing protection for the patient. However, there are several ways in which surgical face masks could potentially contribute to contamination of the surgical wound. Surgical face masks have recently been advocated as a protective barrier between the surgical team and the patient, but the role of the surgical face mask as an effective measure in preventing surgical wound infections is questionable. The aim of the systematic review is to identify and review all randomised controlled trials evaluating disposable surgical face masks worn by the surgical team during clean surgery to prevent postoperative surgical wound infection. All relevant publications about disposable surgical face masks were sought through the Specialised Trials Register of the Cochrane Wounds Group (March 2001). Manufacturers and distributors of disposable surgical masks as well as professional organisations including the National Association of Theatre Nurses and the Association of Operating Room Nurses were contacted for details of unpublished and ongoing studies. Randomised controlled trials (RCTs) and quasi-randomised controlled trials comparing the use of disposable surgical masks with the use of no mask were included. MAIN RESULTS: Two randomised controlled trials were included involving a total of 1453 patients. In a small trial there was a trend towards masks being associated with fewer infections, whereas in a large trial there was no difference in infection rates between the masked and unmasked group. Neither trial accounted for cluster randomisation in the analysis. REVIEWERS' CONCLUSIONS: From the limited results it is unclear whether wearing surgical face masks results in any harm or benefit to the patient undergoing clean surgery.

Hand decontamination.

Hand decontamination is an important intervention in controlling hospital-acquired infections. Dinah Gould examines the issues relating to this, including different decontaminants, the evidence base, the need for improvements in practice, and effective practice.

Surgical gloves: current problems.

One century ago surgical gloves were introduced to practice as part of the new antiseptic technique and originally to protect the hands of the surgeon and his assistants from the harmful dermatologic effects of powerful antiseptics (e.g., carbolic acid) in use at that time. Since then, the wearing of gloves during surgery has been standard practice. Furthermore, the protection value of surgical gloves in preventing cross-infection has stood the test of time. Nevertheless, materials used in glove manufacturing have caused a succession of iatrogenic problems in surgical patients over the years. More recently, emergence of transmissible viruses, such as hepatitis B and C and human immunodeficiency virus, has led surgeons to consider their own safety with the frequent possibility of perforation of surgical gloves by sharp instruments. In this review we discuss the problems associated with surgical glove practice: glove powder-induced peritonitis and adhesions, latex rubber-associated hypersensitivity, and glove perforation.

Electrochemical bacteriocidal action based on electron transfer of salivary bacteria.

Based upon the observation that most oral bacteria are negatively charged, we attempted to restrain the development of oral bacteria in saliva by applying a constant electric potential to an electrode. The development of salivary bacteria was clearly restrained by applying 0.74V electric current for 30 min. This restraint was in inverse proportion to the concentration of the suspension of salivary bacteria. The authors hypothesize that the electrochemical restraining was based on electron transfer between the salivary bacteria and the electrode.

Asepsis yesterday and today

Louis Pasteur; the French Chemist; had exposed microbes as the bane of wound healing long before its appreciation by surgeons. Hence wound infection remained one of the major obstacles to progress in surgery until the development and general acceptance of antisepsis and aseptic surgical techniques. The discovery of antibiotics by Alexander Fleming and the introduction of rubber gloves into surgery by Williams Halsted also contributed notably to the control of wound infections