Effectiveness in Sterilization of Objects Produced by 3D Printing with Polylactic Acid Material: Comparison Between Autoclave and Ethylene Oxide Methods / Eficácia na esterilização de objetos produzidos pela impressão 3D com material ácido polilático: Comparação entre os métodos autoclave e óxido de etileno

Abstract Objective Due to the popularity of 3D technology, surgeons can create specific surgical guides and sterilize them in their institutions. The aim of the present study is to compare the efficacy of the autoclave and ethylene oxide (EO) sterilization methods for objects produced by 3D printing with polylactic acid (PLA) material. Methods Forty cubic-shaped objects were printed with PLA material. Twenty were solid and 20 were hollow (printed with little internal filling). Twenty objects (10 solid and 10 hollow) were sterilized in autoclave, forming Group 1. The others (10 solid and 10 hollow) were sterilized in EO, composing Group 2. After sterilization, they were stored and referred to culture. Hollow objects of both groups were broken during sowing, communicating the dead space with the culture medium. The results obtained were statistically analyzed (Fisher exact test and residue analysis). Results In group 1 (autoclave), there was bacterial growth in 50% of solid objects and in 30% of hollow objects. In group 2 (EO), growth occurred in 20% of hollow objects, with no bacterial growth in solid objects (100% of negative samples). The bacteria isolated in the positive cases was non-coagulase-producing Staphylococcus Gram positive. Conclusions Sterilization by both autoclave and EO was not effective for hollow printed objects. Solid objects sterilized by autoclave did not demonstrate 100% of negative samples and were not safe in the present assay. Complete absence of contamination occurred only with solid objects sterilized by EO, which is the combination recommended by the authors.

Resumo Objetivo Devido à popularidade da tecnologia 3D, cirurgiões podem criar guias cirúrgicos específicos e esterilizá-los nas suas instituições. O objetivo do presente estudo é comparar a eficácia dos métodos de esterilização por autoclave e óxido de etileno (OE) de objetos produzidos pela impressão 3D com material ácido polilático (PLA, na sigla em inglês). Métodos Quarenta objetos em formato cúbico foram impressos com material de PLA. Vinte eram sólidos e 20 eram ocos (impressos com pouco enchimento interno). Vinte objetos (10 sólidos e 10 ocos) foram esterilizados em autoclave, formando o Grupo 1. Os demais (10 sólidos e 10 ocos) foram esterilizados em OE, compondo o Grupo 2. Após a esterilização, os objetos foram armazenados e encaminhados para cultura. Objetos ocos de ambos os grupos foram quebrados durante a semeadura, comunicando o espaço morto com o meio de cultura. Os resultados obtidos foram analisados estatisticamente (teste exato de Fisher e análise de resíduo). Resultados No grupo 1 (autoclave) houve crescimento bacteriano em 50% dos objetos sólidos e em 30% dos objetos ocos. No grupo 2 (OE) o crescimento ocorreu em 20% dos objetos ocos, com ausência de crescimento bacteriano nos objetos sólidos (100% de amostras negativas). A bactéria isolada nos casos positivos foi Staphylococcus Gram positivo não produtor de coagulase. Conclusões A esterilização tanto em autoclave quanto pelo OE não foi eficaz para objetos impressos no formato oco. Objetos sólidos esterilizados em autoclave não demonstraram 100% de amostras negativas, não sendo seguro no presente ensaio. Ausência completa de contaminação ocorreu apenas com objetos sólidos esterilizados pelo OE, sendo a combinação recomendada pelos autores.

Determination of residual impurities in pharmaceutical excipient cetomacrogol 1000 by gas chromatography / 中国药科大学学报

@#For the quality control of cetomacrogol 1000, a gas chromatographic method for the determination of residual impurities in cetomacrogol 1000, such as ethylene oxide, 1, 4-dioxane, ethylene glycol, diethylene glycol and triethylene glycol, was established and validated.The DB-1 column with headspace injection was used to detect ethylene oxide and 1, 4-dioxane with the inlet temperature of 150 °C, the FID temperature of 250 °C, the headspace equilibration temperature of 70 °C and the equilibration time of 45 min.The VF-17MS column with liquid injection was used to detect ethylene glycol, diethylene glycol and triethylene glycol with the inlet temperature of 270 °C, and the FID temperature of 290 °C.The results showed that ethylene oxide and 1,4-dioxane have a good linearity within their specified addition amount ranges (r > 0.999), with the RSD of precision of below 8.0% and the average recovery rates of 90.6% and 101.2%; and that ethylene glycol, diethylene glycol and triethylene glycol also have a good linearity between 3 ? 60 μg/mL (r > 0.999), with the RSD of precision of below 3.0%, and the recovery rates of 96% ~ 103%.The method established in this study has good specificity, linearity, precision and recovery rate, which can effectively detect the multi-component and trace impurities.

Aeração de dispositivos médicos esterilizados a óxido de etileno: considerações acerca da regulação brasileira / Aecization of medical devices sterilized to ethylene oxide: considerations about Brazilian regulation / Aireación de dispositivos médicos esterilizados con óxido de etileno: consideraciones sobre la regulación brasileña

Objetivos: Descrever níveis residuais aceitáveis de óxido de etileno em dispositivos médicos, analisar processos de aeração recomendados e compará-los com a regulação brasileira. Método: Revisão integrativa da literatura, com descritores específicos, sem restrição de ano de publicação. Busca dos dados entre outubro e novembro de 2019, que resultou em 34 estudos incluídos no estudo. Resultados: A regulação brasileira vigente está desatualizada em relação à classificação de produtos, à determinação de valores de resíduos tóxicos de óxido de etileno em dispositivos médicos e aos processos recomendados para a aeração desses produtos, podendo contribuir para riscos de eventos adversos para pacientes usuários de dispositivos inadequadamente aerados, e, consequentemente, urge sua atualização. Conclusão: As lacunas desse marco regulatório beneficiam indiretamente as empresas que terceirizam a esterilização a óxido de etileno ao omitir controles essenciais para a segurança do paciente exposto a possíveis resíduos tóxicos de óxido de etileno, favorecer práticas inseguras de esterilização de produtos para saúde, além de dificultar o controle de serviço de saúde pelas vigilâncias sanitárias do país.

Objectives: To describe acceptable residual levels of ethylene oxide in medical devices, analyze recommended aesther processes and compare them with the Brazilian regulation. Method: Integrative literature review, with specific descriptors, without year of publication restriction. Data search between October and November 2019, which resulted in 34 studies included in the study. Results: Current Brazilian regulation is outdated in relation to product classification, the determination of waste values ethylene oxide toxic in medical devices and the recommended processes for the aecization of these products, and may contribute to risks of adverse events for patients users of inappropriately aenated devices, and consequently urge their update. Conclusion: The shortcomings of this regulatory framework indirectly benefit companies that outsource ethylene oxide sterilization by omitting essential controls for safety of the patient exposed to possible toxic residues of ethylene oxide, unsafe practices of sterilization of health products, in addition to hindering the control of health service by the country's health surveillance.

Objetivos: Describir los niveles residuales aceptables de óxido de etileno (OE) en dispositivos médicos, analizar los procesos de aireación recomendados y compararlos con la normativa brasileña. Método: revisión integrativa de la literatura, con descriptores específicos, sin restricción de año de publicación. Búsqueda de datos entre octubre y noviembre de 2019, que resultó en 34 estudios incluidos en el estudio. Resultados: La normativa brasileña actual está desactualizada en cuanto a la clasificación de productos, determinación y valores de residuos tóxicos de OE en dispositivos médicos y procesos recomendados para la aireación de estos productos, lo que puede contribuir al riesgo de eventos adversos para los pacientes que utilizan una aireación inadecuada de dispositivos y, en consecuencia, se necesita urgentemente una actualización. Conclusión: Las brechas en este marco regulatorio benefician indirectamente a las empresas que externalizan la esterilización a OE, al omitir controles esenciales para la seguridad de los pacientes expuestos a posibles residuos tóxicos de OE, favoreciendo prácticas inseguras de esterilización de productos sanitarios, además de dificultar el control de servicio de salud por la Vigilancia Sanitaria del país.

Source Analysis of Ethylene Oxide Sterilization Residues in Medical Devices / 中国医疗器械杂志

At present, the most commonly used sterilization method for medical devices is ethylene oxide sterilization. The residue after sterilization is closely related to the health of the people who contacted with the medical devices. The study team analyzed the possible residues of medical devices after sterilization with ethyleneoxide. It is suggested that ethylene oxide, 2-chloroethanol and ethylene glycol should be evaluated comprehensively through the analysis of factors such as production links of medical devices, production process of ethylene oxide, sterilization process, sterilization environment and detection method.

Physicochemical and Tissue Response of PLA Nanofiber Scaffolds Sterilized by Different Techniques / Evaluación fisicoquímica y respuesta tisular de andamios nanofibrilares de PLA esterilizados por diferentes técnicas

ABSTRACT In recent years, tissue engineering has evolved considerably, due to the problems in the biomedical area concerning tissue regeneration therapies. Currently, work has been focused on the synthesis and physicochemical characterization of poly lactic acid scaffolds, a synthetic polyester that has been extensively study for its excellent biocompatibility and biodegradability. Moreover, sterilization strategies of scaffold are a crucial step for its application in tissue regeneration, however, the sterilization process have to maintain the structural and biochemical properties of the scaffold. Therefore, it is very important to carry out studies on the sterilization methods of the sample's material, since translational medicine is intended for in vivo applications. The aim of the present study was designed to analyze the effects of different sterilization techniques, i.e. ethylene oxide (ETO), gamma radiation (GR) and hydrogen peroxide- based plasma (H2O2) in biodegradable PLA scaffolds, and to determine the best sterilization technique to render a sterile product with minimal degradation and deformation, and good tissue response. Analysis of surface morphology showed that ETO and GR modified the PLA scaffolds without any change in its chemical composition. Moreover, the histological response showed that the scaffolds are biocompatible and those sterilized by GR showed a more severe inflammatory response, accompanied with the presence of giant foreign body cells. In conclusion, the results show that among sterilization techniques used in the preset study, the best results were observed with H2O2 sterilization, since it did not significantly modify the surface structure of the PLA fibers and their in vivo response did not cause an unfavorable tissue reaction.

RESUMEN En los últimos años, la ingeniería de tejidos ha evolucionado considerablemente, debido a las incógnitas en las terapias de regeneración en el área biomédica. Actualmente, se ha trabajado en la síntesis y caracterización fisicoquímica de andamios de poliácido láctico, el cual es un polímero sintético que se ha estudiado para aplicaciones en ingeniería de tejidos, debido a su biocompatibilidad y biodegradabilidad. El proceso de esterilización es un paso crucial en la aplicación de andamios en terapias de regeneración, sin embargo, la técnica de esterilización debe mantener las propiedades estructurales y bioquímicas del andamio. Por lo tanto, es muy importante realizar estudios sobre los métodos de esterilización de dichos andamios, ya que la medicina traslacional está diseñada para aplicaciones in vivo. El objetivo del presente estudio fue analizar los efectos de diferentes técnicas de esterilización como óxido de etileno (ETO), radiación gamma (GR) y plasma a base de peróxido de hidrógeno (H2O2) en andamios biodegradables de PLA, y determinar la mejor técnica de esterilización con mínima degradación y deformación, así como una respuesta tisular favorable. La estructura de la superficie de los andamios de PLA se modificó principalmente con las técnicas de óxido de etileno y radiación gamma, sin embargo, ninguna técnica modificó su composición química. Con la respuesta histológica se demostró que los andamios de PLA son biocompatibles y que los esterilizados por radiación gamma desencadenan una mayor respuesta inflamatoria y la formación de células gigantes de cuerpo extraño. En conclusión, los resultados muestran que las técnicas de esterilización utilizadas pueden modificar la morfología del andamio, sin embargo; los mejores resultados se observaron con la esterilización por plasma a base de peróxido de hidrógeno, ya que no modificó significativamente la estructura de la superficie de las fibras de PLA y su respuesta in vivo no provocó una reacción desfavorable en el tejido.

A cluster of central retinal artery occlusions following cataract surgery

Purpose: To report a series of central retinal artery occlusions (CRAO) following cataract surgery complicated by posterior capsular rupture (PCR). Methods: Data from 14 patients with acute CRAO following cataract surgery was collected for this study including subject demographics, initial and final best-corrected visual acuity, systemic investigations, optical coherence tomography (OCT) and fundus fluorescein angiography (FFA) findings. Results: Mean subject age was 59.9 ± 12.1 years. Male: Female ratio was 1:1. All patients were operated between October and November 2015 and presented with acute vision loss 1 to 4 days after surgery. All the patients underwent cataract surgery under peribulbar anesthesia and had PCR for which anterior vitrectomy (AV) was done. In all the cases Ethylene oxide (ETO) sterilized vitrectomy probe was used for AV. Clinical picture of CRAO was noted in all the cases during the immediate postoperative period. OCT showed inner retinal layer hyperreflectivity while FFA was normal in all the cases. The final visual acuity was poor in all the eyes. This paper discusses the possible mechanisms of CRAO in these cases. Conclusion: CRAO is a potential complication of peribulbar anesthesia for intraocular surgery in patients with vascular risk factors and hence any substance that can aggravate the vasospasm in such patients should be used cautiously. Vasospasm could be caused by ETO as residual ETO could be present in the vitrectomy machine tubing causing toxicity. It is recommended to be cautious while using ETO sterilized instruments for cataract surgery.

An exploratory study of effectiveness with ethylene oxide treatment for removing DNA contamination / 中国法医学杂志

Objective This exploratory study aimed to assess effectiveness with ethylene oxide treatment for removing DNA contamination. Methods 98 different spiked samples such as saliva, dander, skin cell, hair, blood and cartilage were conducted with ethylene oxide treatment. After extraction of samples, the dna was amplified and then the STR analysis was performed with 3130xl or 3500xl. Results A 6h EO treatment results showed that two saliva stains of 44 samples STR profile were detected; Just one hair of 54 samples treated with ethylene oxide was detected contaminating DNA with EO treatment for 8 hours. Conclusion This work suggested that it was more successful to reduce DNA contamination by using ethylene oxide treatment.

retention of poloxamer-basedhydrogels for vaginal application in mouse and rat models

The purpose of this study is to evaluate theretention capabilities of poloxamer-basedhydrogels for vaginal application with nonoxinol-9 as the model drug. Twohydrogel formulations, which contained 18% poloxamer 407 plus 1% poloxamer 188 (GEL1, relative hydrophobic) or 6% poloxamer 188 (GEL2, relative hydrophilic), were compared with respect to the rheological properties,hydrogel erosion and drug release. The vaginal retention capabilities of these hydrogel formulations were further determined in two small animal models, including drug quantitation of vaginal rinsing fluid in mice and isotope tracing withTc in rats. The two formulations exhibited similar phase transition temperatures ranging from 27 to 32 °C. Increasing the content of poloxamer 188 resulted in higher rheological moduli under body temperature, but slightly accelerated hydrogel erosion and drug release. When compared, GEL1 was eliminated significantly slower in rat vagina than GEL2, while the vaginal retention of these two hydrogel formulations behaved similarly in mice. In conclusion, increases in the hydrophilic content of formulations led to faster hydrogel erosion, drug release and intravaginal elimination. Rats appear to be a better animal model than mice to evaluate thehydrogel for vaginal application.

Reversible Cerebral Vasoconstriction Syndrome Complicated with Cerebral Infarct after Inhaling Ethylene Oxide Gas

Reversible cerebral vasoconstriction syndrome (RCVS) is characterized by thunderclap headache and multiple reversible intracranial vasoconstrictions. Here we report a case of RCVS after exposure to ethylene oxide (EO) gas, which is a widely used sterilant. A 34-year-old woman presented with aphasia, right-arm weakness, and severe headache after inhaling EO gas. Brain imaging revealed multiple infarcts and multiple intracranial stenoses. The stenotic lesions completely regressed on follow-up CT angiography. This is the first report of RCVS after exposure to EO gas.

Different disinfection solution on the disinfection effect analysis of the fiberoptic bronchoscopy biopsy forceps / 中国医学装备

Objective: Discuss different sterilization solution on the disinfection effect of fiberoptic bronchoscopy biopsy forceps. Methods:To ethylene oxide sterilization, glutaraldehyde immersion disinfection and high pressure steam sterilization of three methods of fiberoptic bronchoscopy biopsy forceps disinfection sterilization rate, the contamination rate and use fixed number of year for effect comparison. Results: Qualification rate of epoxy ethane sterilizing method were higher than in glutaraldehyde soaking method and high pressure steam sterilization disinfection method, and the pollution rate is significantly lower than the other two groups, the service life of the equipment increase. Conclusion:Low-temperature ethylene oxide sterilization of fiberoptic bronchoscopy biopsy forceps sterilization effect is good, and the pollution rate is low, service life is longer.

Citotoxicidade de tubos de PVC esterilizados em óxido de etileno após exposição à radiação gama / Cytotoxicity of PVC tubes sterilized in ethylene oxide after gamma radiation exposure / Citotoxicidad de tubos de PVC esterilizados en óxido de etileno luego de exposición a la radiación gamma

Materiais esterilizados em raios gama, ao serem re-esterilizados em óxido de etileno (EO), formam substâncias tóxicas? Esta questão norteou o objetivo deste estudo, que foi investigar o potencial efeito citotóxico do PVC esterilizado em radiação gama e re-esterilizado em EO pelo método da difusão em ágar em culturas celulares. Nove tubos de PVC foram submetidos à esterilização em radiação gama e re-esterilizados em EO. Os tubos foram divididos em um total de 81 unidades de análise, que foram testadas de forma a representar as superfícies internas, externas e massa de cada tubo. Concluiu-se que os materiais de PVC esterilizados em Radiação Gama e consecutivamente re-esterilizados em EO não são citotóxicos.

Do materials sterilized using gamma rays become toxic when re-sterilized in ethylene oxide? This question guided the objective of this study, which was to investigate the potential cytotoxic effect of PVC sterilized by gamma radiation and re-sterilized with EO by the agar diffusion method in cell cultures. Nine PVC tubes were subjected to gamma radiation sterilization and were re-sterilized in EO. The tubes were divided into a total of 81 units of analysis that were tested so as to represent the internal and external surfaces and mass of each tube. It was concluded that the PVC materials sterilized in gamma radiation and re-sterilized in EO are not cytotoxic.

Los materiales esterilizados con rayos gama, al ser re-esterilizados en óxido de etileno (EO), ¿forman substancias tóxicas? Esta pregunta orientó el objetivo del presente estudio, que fue investigar el potencial efecto citotóxico del PVC esterilizado en radiación gamma y re-esterilizado en EO por el método de difusión en agar en cultivos celulares. Nueve tubos de PVC fueron sometidos a esterilización por radiación gamma y re-esterilizados en EO. Se les aplicaron en total 81 unidades de análisis, las cuales fueron testeadas de manera tal de representar las superficies internas, externas y la masa de cada tubo. Se concluyó en que los materiales de PVC esterilizados con Radiación Gamma y, posteriormente, con EO, no son citotóxicos.

Tejido óseo esponjoso esterilizado con gas óxido de etileno / Spongy bone tissue sterilized with ethylene oxide gas / Tissu osseux spongieux stérilisé à l'oxyde d'éthylène gazeux

Objetivo: comprobar las propiedades esterilizantes del gas óxido de etileno sobre el hueso esponjoso empleado como implante en la clínica médica, fundamentalmente su eficacia para determinados microorganismos y el tiempo necesario de su uso en autoclave industrial. Métodos: se prepararon 54 porciones de tejido óseo esponjoso en forma de cubo separados en 3 grupos de 18 porciones cada uno. El primer grupo se empleó para evaluar un método de contaminación bacteriológica con cepas de microorganismos conocidos. El segundo y tercer grupo una vez contaminados con los microorganismos conocidos se sometieron a la acción del gas óxido de etileno en subgrupos de 6, durante 60, 90 y 120 min. Resultados: en el primer grupo el 100 % de las muestras contaminadas se presentaron positivas. En los grupos segundo y tercero la efectividad del gas óxido de etileno resultó de 100 % a los 120 min. Conclusión: este método es seguro, por lo que es apropiado para el empleo en la clínica médica.

Objective: verify the sterilizing properties of ethylene oxide gas over the spongy bone used for implants in medical practice, mainly its efficacy against certain microorganisms and the time required for sterilization in industrial autoclaves. Methods: 54 cube-shaped spongy bone tissue samples were prepared and distributed into 3 groups, each with 18 samples. The first group was used to evaluate a bacteriological contamination method with strains of known microorganisms. Upon contamination with the known microorganisms, the second and third groups were subjected to the effect of ethylene oxide gas in subgroups of 6 samples during 60, 90 and 120 minutes. Results: in the first group 100 % of the samples contaminated were positive. In the second and third groups, the effectiveness of ethylene oxide gas was 100 % at 120 minutes. Conclusion: this is a safe method appropriate for use in medical practice.

Objectif: confirmer les propriétés stérilisantes de l'oxyde d'éthylène gazeux sur l'os spongieux utilisé comme implant dans la clinique médicale, notamment son efficacité contre certains microorganismes, et le temps nécessaire pour l'utiliser dans un autoclave industriel. Méthodes: cinquante-et-quatre portions de tissu osseux spongieux ont été préparées sous forme de cube, et séparées en 3 groupes de dix-huit portions chacun. Le premier groupe a été utilisé pour évaluer une méthode de contamination bactériologique à souches de microorganismes connus. Une fois contaminés par des microorganismes connus, les deuxième et troisième groupes ont été soumis à l'action de l'oxyde d'éthylène gazeux en sous-groupes de 6 au cours de 60, 90 et 120 minutes. Résultats: dans le premier groupe, 100 % des échantillons contaminés ont été positifs. Dans les deuxième et troisième groupes, l'efficacité de ce gaz a réussi 100 % à 120 minutes. Conclusion: cette méthode est sure, donc appropriée, pour la clinique médicale.

The use of vancomycin-loaded poly-l-lactic acid and poly-ethylene oxide microspheres for bone repair: an in vivo study

OBJECTIVE: The aim of this study was to investigate bone repair after the implantation of vancomycin-loaded poly-L-lactic acid/poly-ethylene oxide microspheres compared with vancomycin-unloaded poly-L-lactic acid/poly-ethylene oxide microspheres. METHODS: Poly-L-lactic acid/poly-ethylene oxide microspheres were implanted in rat tibiae and evaluated for periods of 2, 4, 8, and 12 days and 4, 8, 16, and 32 weeks. The groups implanted with vancomycin-loaded and vancomycin-unloaded microspheres were compared. Histopathologic (semi-quantitative) and histomorphometric analyses were performed to evaluate the bone formation process. RESULTS: During the first period (second day), fibrin and hemorrhaging areas were observed to be replaced by granulation tissue around the microspheres. Woven bone formation with progressive maturation was observed. All of the histopathological findings, evaluated by a semi-quantitative assay and a quantitative analysis (percentage of bone formation), were similar between the two groups. CONCLUSION: Vancomycin-loaded poly-L-lactic acid/poly-ethylene oxide microspheres are a good bone substitute candidate for bone repair. Local antibiotic therapy using vancomycin-loaded poly-L-lactic acid/poly-ethylene oxide microspheres should be considered after the microbiological evaluation of its efficacy.

Apósito biológico esterilizado con gas óxido de etileno / A biological dressing sterilized using ethylene oxide gas

Objetivo: se presentó el resultado de una investigación preclínica dirigida a comprobar el poder esterilizante del gas óxido de etileno sobre la piel porcina empleada como apósito biológico. Métodos: se contaminaron 2 grupos de 60 muestras cada uno, de piel porcina liofilizada con una cepa de estafilococo coagulasa positivo y Pseudomona aeruginosa, respectivamente. El 25 por ciento de las muestras de cada grupo se envió al laboratorio de microbiología para comprobar la efectividad del método de contaminación. El 75 por ciento restante se trató durante diferentes períodos en una cámara de gas óxido de etileno y, posteriormente, se enviaron al laboratorio de microbiología para comprobar el grado de esterilidad. Resultados: se demostró la alta efectividad del gas óxido de etileno para esterilizar la piel porcina que es empleada como apósito biológico. Conclusiones: este método es seguro, por lo que es apropiado para el empleo en la clínica médica

Objective: to present the result from a preclinical research aimed to verify the sterilizing power of ethylene oxide gas on the porcine skin used as a biological dressing. Methods: two groups of 60 samples each of lyophilized porcine skin were contaminated with a strain of positive-coagulase staphylococcus and Pseudomona aeruginosa, respectively. The 25 percent of samples of each group was sent to microbiology laboratory to verify the effectiveness of contamination method. The remainder 75 percent was treated in different periods in a chamber of ethylene oxide gas and later, was sent to the above laboratory to verify the sterility degree. Results: it was demonstrated the effectiveness of the ethylene oxide gas to sterilize the porcine skin, which is used as a biological dressing. Conclusions: this method is safe, therefore it is appropriate to use in the medical clinic

Sterilization of single-use helical stone baskets: an experimental study / Esterilização de cestas helicoidais descartáveis extratoras de cálculo: um estudo experimental

Objectives: To experimentally evaluate the efficacy of a standard sterilization protocol employed during reuse of disposable helical stone baskets. Methods: Study performed on 20 helical stone baskets: 10 were used in the initial validation process, contaminated with Escherichia coli ATCC 25922 and imprinted on Müeller-Hinton media; 10 catheters were contaminated with Geobacillus stearothermophilus ATCC 7953, processed, inoculated in TSB and incubated in a water bath at a temperature of 55ºC. Bacterial growth was evaluated after 1, 3, 5 and 7 days. After sterilization, stone baskets were also opened and closed 40 times to check for functional problems. All plastic and basket parts were carefully checked for damages. Results: After the 72-hour incubation period, there was growth of E. coli ATCC 25922 in 100% of imprints. After the sterilization process and up to 7 days incubation period on a blood agar plate, there was no growth of G. stearothermophilus ATCC 7953 or any other bacteria. There were no functional problems or damage to baskets after the sterilization process. Conclusion: The ethylene oxide system is efficacious and safe for sterilization of disposable helical stone baskets. However, further clinical studies are required and should provide more safety information.

Objetivo: Avaliar experimentalmente a eficácia de um protocolo padrão de esterilização de cestas helicoidais descartáveis extratoras de cálculo. Métodos: Estudo realizado com 20 cestas helicoidais descartáveis extratoras de cálculo: 10 foram utilizadas no processo inicial de validação do método, contaminadas com Escherichia coli ATCC 25922 e semeadas em meio de Müeller-Hinton; 10 foram contaminadas com Geobacillus stearothermophilus ATCC 7953, processadas, inoculadas em TSB e incubadas em banho maria, a 55 ºC. O crescimento bacteriano foi avaliado depois de 1, 3, 5 e 7 dias. Após a esterilização, as cestas helicoidais descartáveis extratoras de cálculo foram abertas e fechadas 40 vezes para avaliar problemas funcionais. Todas as partes plásticas foram avaliadas quanto a danos. Resultados: Após as 72 horas de incubação, observou-se crescimento de E. coli ATCC 25922 em todos os meios. Após a esterilização e até 7 dias de incubação, não houve crescimento de G. stearothermophilus ATCC 7953 ou de qualquer outra bactéria. Não foram observados problemas funcionais ou danos nas cestas após a esterilização. Conclusão: O processo de esterilização com óxido de etileno é seguro e eficaz para re-esterilizar cestas helicoidais descartáveis extratoras de cálculo descartáveis. Contudo, são necessários mais estudos clínicos para fornecer mais informações sobre segurança.

Risk Factors for Breast Cancer, Including Occupational Exposures

The knowledge on the etiology of breast cancer has advanced substantially in recent years, and several etiological factors are now firmly established. However, very few new discoveries have been made in relation to occupational risk factors. The International Agency for Research on Cancer has evaluated over 900 different exposures or agents to-date to determine whether they are carcinogenic to humans. These evaluations are published as a series of Monographs (www.iarc.fr). For breast cancer the following substances have been classified as "carcinogenic to humans" (Group 1): alcoholic beverages, exposure to diethylstilbestrol, estrogen-progestogen contraceptives, estrogen-progestogen hormone replacement therapy and exposure to X-radiation and gamma-radiation (in special populations such as atomic bomb survivors, medical patients, and in-utero exposure). Ethylene oxide is also classified as a Group 1 carcinogen, although the evidence for carcinogenicity in epidemiologic studies, and specifically for the human breast, is limited. The classification "probably carcinogenic to humans" (Group 2A) includes estrogen hormone replacement therapy, tobacco smoking, and shift work involving circadian disruption, including work as a flight attendant. If the association between shift work and breast cancer, the most common female cancer, is confirmed, shift work could become the leading cause of occupational cancer in women.

Compatibilidades e incompatibilidades entre radiação gama e óxido de etileno como métodos sucessivos de esterilização / Compatibilities and incompatibilities between gamma rays and ethylene oxide as consecutive sterilization methods / Compatibilidades e incompatibilidades entre rayos gama y óxido de etileno como métodos sucesivos de esterilización

A dúvida sobre a questão da re-esterilização de artigos confeccionados com cloreto de polivinila (PVC), esterilizados em radiação gama (RG) e posteriormente em óxido de etileno (EO) persiste até os dias atuais. Por meio da revisão integrativa da literatura, este artigo analisou estudos que evidenciaram compatibilidades e incompatibilidades entre os processos de esterilização com RG e EO quando utilizados como métodos sucessivos de esterilização. Foram analisados 7 estudos. Constatou-se que há influência multifatorial na segurança do procedimento e que o método analítico da cromatografia empregado na maioria dos estudos produziu resultados controversos. Esse fato indica a necessidade da realização de novos estudos sobre o assunto, utilizando-se métodos analíticos mais sensíveis do que a cromatografia gasosa, como o teste de reatividade biológica em culturas celulares, que poderá dirimir em nosso meio a crônica dúvida da compatibilidade ou incompatibilidade de se esterilizar em EO materiais previamente gamairradiados.

The doubt regarding the re-sterilization of articles made of polyvinyl chloride (PVC) sterilized with gamma radiation (GR) and subsequently with ethylene oxide (EO) persists to date. Through a systematic literature review, this article analyzed studies that demonstrated compatibilities and incompatibilities between the sterilization processes with GR and EO, when used as consecutive sterilization methods. Seven studies were analyzed. It was verified that there is a multifactor influence regarding the safety of the procedure and that the chromatography analytical method employed by most studies yielded controversial results. This fact indicates the need for further studies on the issue, using more sensitive analytical methods than gas chromatography, such as the biological reactivity test in cell cultures, in an attempt to clarify the chronic doubt regarding the adequacy or inadequacy of sterilizing previously gamma-irradiated materials with EtO.

La duda sobre la cuestión de la reesterilización de artículos confeccionados con policloruro de vinilo (PVC) esterilizados con Rayos Gamma (RG) y posteriormente en óxido de etileno (EO) persiste hasta la actualidad. A través de la revisión integradora de la literatura, este artículo analizó estudios que evidenciaron compatibilidades e incompatibilidades entre los procesos de esterilización con RG y EO, cuando se utilizan en forma sucesiva. Fueron analizados 7 estudios. Se constató que hay influencia multifactorial en la seguridad del procedimiento y que el método analítico de cromatografía empleado en la mayoría de los estudios generó resultados controversiales. Este hecho indica la necesidad de realizar nuevos estudios sobre el asunto, utilizando métodos analíticos más sensibles que la cromatografía gaseosa, tales como el test de reactividad biológica en cultivos celulares para dirimir en nuestro medio la crónica duda de la compatibilidad o incompatibilidad de esterilizar en EO materiales previamente irradiados con Rayos Gamma.

Health Effects of Chemicals used in hospitals among Healthcare Workers

Healthcare workers are exposed to a variety of chemical agents used in many different areas and purposes. The chemicals could cause health problems to healthcare workers using them. Glutaraldehyde is a kind of disinfectant and used for endoscopes, catheters, and many kinds of operating apparatus. It may cause allergic contact dermatitis. Formaldehyde is another disinfectant and can be used for fixing tissues. Formaldehyde was classified to a Group 1 carcinogen by IARC and it may cause lung or nasal cancer. Ethylene Oxide gas is the most popular disinfectant these days and may be applied to many health care sets or linens. EO gas may cause allergic contact dermatitis and breast cancer or leukemia. It is also classified as Group 1 carcinogen despite limited evidence for human cancers. Anesthetics are related to genotoxicities, sister chromatid exchange, and might be related to spontaneous abortion, stillbirth or birth defects. Some of the anti-neoplastic drugs such as Busulfan, Chlorambucil, cyclophosphamide, melphalan are Group 1 carcinogens. They could cause nausea, pruritus, or decreasing leukocytes or platelets. Other miscellaneous chemical agents are heavy metals such as elementary mercury or lead and organic solvents such as toluene, xylene and acetone. Although some of these chemical agents including EO gas have occasionally exceeded to permissible level, air levels of most above chemicals in Korean hospitals were relatively low. However, we have to make every effort to reduce the exposure level of these chemicals.

Evaluation of the sterilization efficacy of domestic electric drills used in orthopaedic surgeries / Avaliação da eficácia da esterilização de furadeiras elétricas domésticas utilizadas em cirurgias ortopédicas

It is estimated that electric drills (ED) have been used in orthopaedic surgeries for bone drilling for more than 50 years in Brazilian hospitals. It is an electric, thermosensitive equipment, not indicated for surgical use, which has not been previously evaluated regarding the sterilization efficacy, being suspect of infection risk. This study evaluated the efficacy of sterilization by ethylene oxide (EtO) of new drills that were intentionally contaminated with Bacillus atrophaeus spores. An experimental, laboratory, randomized applied research was developed, where 16 electric drills were analyzed, in addition to positive and negative controls. All the previously cleaned and sterilized equipment were submitted to contamination by spores. The experimental group was submitted to cleaning and sterilization by EtO and test of sterility by filtration through a 0.45 µm membrane. The membranes were cultivated and Gram and Wirtz-Conklin staining were carried out in positive results for spore visualization. An efficacy of 99.99999881 percent of the process of sterilization by EtO was confirmed, with a probability of survival of 1.19 x 10-8. Under the development conditions of the experiment, the efficacy of the sterilization of ED by EtO was confirmed.

Estima-se que há mais de 50 anos, as furadeiras elétricas têm sido empregadas em cirurgias ortopédicas nos hospitais brasileiros para a perfuração óssea. Trata-se de equipamento elétrico, termossensível, não indicado para uso cirúrgico, não avaliado anteriormente quanto à eficácia da esterilização, suspeitando-se de risco para infecções. Esse estudo avaliou a eficácia da esterilização por óxido de etileno (ETO) de furadeiras novas intencionalmente contaminadas com esporos de Bacillus atrophaeus. Foi desenvolvida pesquisa experimental, laboratorial, randomizada e aplicada onde foram analisadas 16 furadeiras elétricas, além de controle positivo e negativo. Todos os equipamentos previamente limpos e esterilizados foram submetidos à contaminação com esporos. O grupo experimental foi submetido à limpeza e esterilização por ETO e teste de esterilidade por filtração por membrana de 0,45 µm. As membranas foram cultivadas e para resultados positivos foram realizadas coloração de Gram e Wirtz-Conklin para visualização dos esporos. Foi comprovada a eficiência de 99,99999881 por cento do processo de esterilização por ETO, com a probabilidade de sobrevivência de 1,19 x 10-8. Nas condições do desenvolvimento do experimento, a eficácia da esterilização das FE por ETO foi comprovada.

Aductos de hemoglobina y micronúcleos en trabajadores hospitalarios expuesto a óxido de etileno: Venezuela / Hemoglobin adducts and micronuclei in hospital workers exposed to ethylene oxide: Venezuela

El óxido de etileno (OE) es un cancerígeno genotóxico con habilidad para reaccionar con macromoléculas biológicas, como la Hemoglobina y Acido desoxirribonucléico (ADN), formando N-(2-hidroxietil)valina (HEV) y 7-(2-hidroxietil)-guanina (7-HEG) respectivamente, compuestos llamados aductos. Estudio descriptivo, cuyo propósito fue evaluar trabajadores del área de esterilización de un hospital público expuestos a OE, mediante la determinación de aductos de hemoglobina, micronúcleos en linfocitos (MN), tioeteres en orina y parámetros hematológicos. La muestra estuvo conformada por 10 individuos expuestos (GE) entre 24 y 56 años y 9 sujetos control (GC) con el mismo rango de edad de una universidad pública. El valor medio de N-(2-hidroxietil)valina (HEV) (pmol/g globina), en el GE fue 6758,5 ± 4143,6 y de 465,7 ± 484,5 en el GC (p < 0,0001), para MN x 1000 células, en el GE el valor medio fue de 4,8 ± 2,5 y de 0,7 ± 0,8 en el GC (p < 0,0001); Para la concentración de tioéter (mmolesSH/mol de creatinina), se obtuvo en el GE 38,5 ± 22,6 y en el GC 23,2 ± 8,8, encontrándose diferencias significativa al 5% (p=0,04), entre ambos grupos. Los parámetros hematológicos estudiados en GE y GC, puso en evidencia disminución de hemoglobina y hematocrito en el GE con una diferencia significativa entre las medias, de la hemoglobina (p=0,03) y en el hematocrito (p=0,04). Concluyéndose que los resultados son consistentes con algunos estudios previos de biomonitoreo ocupacional, demostrándose la importancia de disponer de una batería de biomarcadores en la evaluación de la exposición al OE.

Ethylene oxide (EO) is a genotoxic carcinogen, able to react with biological macromolecules such as hemoglobin and deoxyrebonucleic acid (DNA) to form N-(2-hydroxyethyl)valine (HEV) and 7-(2-hydroxyethyl)-guanine (7-HEG), respectively; these compounds are known as adducts. We evaluated biomarkers of effect and exposure workers from the central sterilization unit of a public hospital. The purpose of this descriptive study was to evaluate 10 EO-exposed employees (GE), ranging in age from 24 to 56 years, and 9 control workers from a public university (GC) of similar age.. The mean value of N-(2-hydroxyethyl)valine (HEV)(pmol/mol globin) in the GE group was 6758.6 ± 4143.6 and 465.7 ± 484.5 in the GC group; for micronuclei (MN) in lymphocytes (MNx1000 cells), the mean value in GE was 4.8 ± 2.5 and for GC it was 0.7 ± 0.8 in GC (p< 0,0001). Thioether concentrations (mmoles SH/mol creatinine), were also significantly higher in GE (38.5 ± 22.6) than in GC (23.2±8.8) (p=0,04). Standard hematological indices (hemoglobin and hematocrit) were lower in GE than in GC (p=0.03 and 0.04, respectively). These results agreed with some prior occupational biomonitoring studies that demonstrate the importance of using biomarker batteries in the evaluation of exposure to EO.