Usos y limitaciones de la lámpara ultravioleta germicida portátil para la desinfección de superficies.

RESUMENLa morbimortalidad causada por infecciones vinculadas a la atención sanatoria ha llevado a cuestionar si los métodos de desinfección convencionales son inadecuados y se requieren métodos complementarios, como la fumigación de la habitación y la irradiación ultravioleta. Ello ha dado lugar a la preocupación por que estos métodos alternativos puedan poner en riesgo al personal sanitario y a los pacientes.Objetivos. (1) Determinar la eficacia de la lámpara ultravioleta C germicida portátil para la desinfección de superficies, (2) evaluar el cambio de la humedad relativa (HR) y las distintas distancias específicas en las tasas de letalidad bacteriana, y (3) evaluar los posibles problemas a que conlleva la exposición.Métodos. En el presente estudio se investiga si una lámpara germicida portátil puede desinfectar de forma eficaz superficies tratadas con esporulación o germinación bacteriana y se evalúa el efecto de condiciones ambientales cambiantes, como la humedad relativa (HR), la posición y las distancias específicas, en las tasas de letalidad germicida.Resultados. Se constató una mejor tasa de letalidad con una HR de 40-65% y en un rango de temperatura de 21-24°C. Tanto la HR alta como la HR baja interfirieron con la capacidad de la radiación UV-C para inactivar la germinación microbiana. En el caso de la esporulación bacteriana, el aumento del secado de la superficie fue el factor de mayor importancia para aumentar la tasa de letalidad.Conclusiones. En esta investigación se demostró la eficacia de la radiación UV-C bajo condiciones óptimas, irradiación directa y una distancia específica corta (12.7 cm). Sin embargo, cuando es utilizada en condiciones que no son óptimas existen limitaciones. El aumento de la distancia y los ángulos de irradiación indirecta resultaron en tasas de letalidad más bajas. Cabe señalar que durante su uso es importante minimizar la exposición innecesaria de pacientes y personal sanitario.

The uses and limitations of a hand-held germicidal ultraviolet wand for surface disinfection.

The morbidity and mortality from healthcare associated infections has raised concern that conventional disinfection methods are inadequate and that other adjunct methods such as room fumigation and ultraviolet irradiation may be needed. There is also concern that these alternative methods may pose a risk to workers and patients. OBJECTIVES: (1) Determine the efficacy of a germicidal UV-C wand for surface disinfection, (2) evaluate changing relative humidity (RH) and different target distances on bacteria kill rates, and (3) assess potential exposure concerns. METHODS: This study investigates whether a hand-held germicidal wand can efficaciously disinfect surfaces treated with either a vegetative or spore forming bacterium and to evaluate the effect of changing environmental conditions such as relative humidity (RH), target position, and target distances on microbial kill rates. RESULTS: Kill rate was best at 40-65% RH at a temperature range of 21-24°C. Both high and low RH interfered with the ability of UV-C to kill the vegetative microbe. In the case of the spore forming bacterium, increased surface drying time was the most significant factor increasing kill rate. CONCLUSIONS: This research demonstrates that UV-C was efficacious under optimal conditions, a direct beam exposure, and a short target distance (12.7 cm). However, there are limitations when used in non-optimal conditions. Increased distance and indirect beam angles resulted in lower kill rates. It is also important to minimize unnecessary patient and worker exposure during its use.

The risks and benefits of chemical fumigation in the health care environment.

Fumigation of hospital rooms with high concentrations of toxic chemicals has been proposed to reduce microbial agents on hospital surfaces and to control infections. Chemical fumigation has been used effectively in other areas, such as building decontamination after bioterrorism events, in agriculture, and in residential structures. However, even in these situations, there have been incidents where fumigants have escaped, causing illness and death to exposed workers and the public. Before expanding the use of a potentially hazardous technology in areas where there are vulnerable individuals, it is important to fully weigh benefits and risks. This article reviews the effectiveness of fumigation as a method of inactivating microbes on environmental surfaces and in reducing patient infection rates against the potential risks. Peer-reviewed literature, consensus documents, and government reports were selected for review. Studies have demonstrated that fumigation can be effective in inactivating microbes on environmental surfaces. However, the current consensus of the infection control community is that the most important source of patient infection is direct contact with health care workers or when patients auto-infect themselves. Only one peer-reviewed, before-after study, at one hospital reported a significant reduction in infection rates following chemical fumigation. The limitations of this study were such that the authors acknowledged that they could not attribute the rate reduction to the fumigation intervention. A serious concern in the peer-reviewed literature is a lack of evidence of environmental monitoring of either occupational or non-occupational exposures during fumigation. Currently, there are neither consensus documents on safe fumigation exposure levels for vulnerable bedridden patients nor sampling methods with an acceptable limit of detection for this population. Until additional peer-reviewed studies are published, demonstrating significant reductions in patient infection rates following chemical fumigation and consensus guidance on the safe exposure levels and monitoring methods, chemical fumigation in health care should be conducted only in the most stringently controlled research settings.

Attributions, stress, and work-related low back pain.

Occupational low back pain (LBP) is a major cause of morbidity and cost. Efforts to control LBP are largely unsuccessful, and better understanding of risks is needed, especially psychological factors. The purpose of this research was to assess the association between worker attributions and LBP. Attributing LBP to internal causes may increase the worker's perceived control, whereas external attribution may cause distress. A new model was developed to explore these associations. A cross-sectional design was used in this study of 278 garment workers. Data were gathered by a self-administered questionnaire and through direct observation. Responses to questions on worker attributions of LBP cause and knowledge of back safety were subjected to factor analysis and other psychometric evaluation to develop scales. Six hypotheses were tested using multivariate logistic regression. Workers who scored high in internal attribution were more likely to be knowledgeable of back safety (OR = 3.7, 95% CI = 2.0-6.7). Workers reporting high demand were more likely to report LBP (OR = 2.3, 95% CI = 1.2-4.4). Workers attributing LBP to job tasks were more likely to report LBP (OR = 3.2, 95% CI = 1.5-6.9), and those reporting high supervisor support were less likely to report LBP (OR = 0.23, 95% CI = 0.08-0.66). Workers with annual incomes above 15,000 dollars were more likely to report LBP in the test of both the Demand-Control-Support and Attribution models (OR = 2.8, 95% CI = 1.2-6.9 and OR = 4.1, 95% CI = 1.5-11.1, respectively). While both models appeared to be useful for the study of low back pain, the R(2)(L) of the Demand-Control-Support model equaled only 11.9 percent, whereas the Attribution model equaled 26.2 percent. This study provides evidence that attribution theory is useful in the study of LBP, including in future interventions in the prevention of LBP.

Risk factors for work-related low back pain in registered nurses, and potential obstacles in using mechanical lifting devices.

Back pain disability is a serious and costly problem affecting the nursing profession. The purposes of this study were to determine risk factors for work-related low back pain (WRLBP) in registered nurses and to record the reported use or reasons for nonuse of mechanical lifts. Our hypothesis was that workers who attributed the cause of WRLBP to their own actions would be knowledgeable about back safety, would be more likely to use lifts, and would report less WRLBP. A random sample of 270 registered nurses was selected from two acute care hospitals in central Illinois to identify WRLBP risk factors. This cross-sectional study gathered information on individual, physical workload, psychological, and organizational factors that may present a risk for WRLBP. Information was also collected on the use of safety devices and back pain symptoms. The response rate was 50.4%. Nearly 84% of respondents had WRLBP in the past, and 36.2% had WRLBP in the past year that limited movement or interfered with routine activities. Among the risk factors significantly associated with WRLBP were more years worked in nursing, frequent lifting, and low social support. Only 11% reported that they routinely used mechanical lifting devices, and the primary reason given for failure to use lifting equipment was unavailability of equipment. The reasons for the lack of use of mechanical lifts should be investigated and addressed.

A new direction in low-back pain research.

This article suggests reasons for the difficulty in understanding and preventing low-back pain (LBP), provides a framework for understanding the causes of reported LBP, and highlights an important new direction in research that could accelerate progress in reducing LBP. Fundamental to understanding LBP is the recognition that it is a symptom not an underlying condition. Worker reports of LBP depend not only on the extent and nature of underlying injury but also the worker's perceptions and the likelihood of reporting the symptoms. Each of these factors, in turn, depends on a number of other proximal and distal factors. Identifying the root causes of underlying injury is essential to improving prevention programs. Yet, many of the methods used to study LBP and its causes have serious shortcomings, adding to the confusion over appropriate preventive strategies. An important gap in LBP research has been the factors influencing preventive behaviors for both workers and managers. If workers or managers attribute the causes of LBP to the wrong factors, preventive behaviors will be misdirected and ineffective. Attribution theory, a relatively recent application in the occupational health field, offers promise for identifying incorrect attributions and modifying these attributions so that appropriate protective actions are taken.