Avaliação da segurança da esterilização por peróxido de hidrogênio vaporizado nas práticas atuais do centro de material e esterilização / Safety Assessment of Vaporized Hydrogen Peroxide Sterilization in the Current Practices of Central Sterile Service Departments

Introdução: O recente avanço das técnicas cirúrgicas demandou a utilização de métodos de esterilização a baixa temperatura, tal como o peróxido de hidrogênio vaporizado (VH2O2), para possibilitar a esterilização de produtos para saúde (PPS) termossensíveis. Embora amplamente utilizado nos Centros de Material e Esterilização (CME), os problemas relacionados à esta tecnologia são muitos, tais como: baixa difusibilidade do VH2O2, ausência de normas construtivas e de validação, limitação das tecnologias para medir a concentração do agente esterilizante, validação e monitoramento dos ciclos, além de práticas inadequadas de carregamento e esterilização de PPS. Objetivo: Avaliar, por meio de indicadores físicos (IF) e biológicos (IB), se as práticas atuais do CME, na escolha das cargas e do carregamento, interferem na segurança dos esterilizadores de VH2O2: Sterrad® 100S ciclo curto, Sterrad® 100NX ciclo padrão e Vpro® Max ciclo sem lúmen. Método: Pesquisa de campo, exploratória e descritiva, realizada em hospitais que utilizam os equipamentos supracitados na rotina. Os dados foram coletados após aprovação do Comitê de Ética e Pesquisa e autorização dos hospitais participantes. Foram avaliados três esterilizadores de cada modelo de CMEs distintos, sendo que a escolha dos ciclos para coleta dos dados deu-se pela maior criticidade e frequência de utilização nos locais de estudo. Os IB foram posicionados, unitariamente, em envelopes duplos de Tyvek® (considerados pacote-teste), com fechamento por selagem térmica. Em cada esterilizador, foi realizado um ensaio vazio em meio ciclo, com três pacotes-testes nas seguintes posições: superior/anterior; superior/centro e inferior/posterior. Sequencialmente, foram realizados ensaios com a mesma carga em triplicata, compostos pelos PPS que representam um desafio à rotina, também, em meio ciclo. Internamente, adicionaram-se IB, além de dois pacotes-testes posicionados na parte superior/anterior e inferior /posterior, sendo o primeiro colocado no ponto mais próximo da entrada do agente esterilizante, e o segundo colocado no ponto mais distante. Resultados: do total de 9 ensaios com carga para cada modelo de esterilizador, obtemos IB positivos em 22% dos ensaios do modelo 100S, 33% no modelo 100NX e 100% no modelo V-pro. Os IB positivos foram relacionados à sobreposição de pacotes, à presença de tapete imantado, às bandejas de acondicionamento sem instrução de uso do fabricante (IUF) para o método e, principalmente, à difusibilidade do VH2O2 prejudicada em pontos mais distantes da entrada do VH2O2 na câmara de esterilização. Outras hipóteses que podem ter contribuído para o resultado foram a falta de IUF dos PPSs para o método e o uso de massa adicional que consome o VH2O2. Não foi possível correlacionar os resultados dos IB positivos aos parâmetros físicos do esterilizador, bem como ao total de peso da carga. Conclusão: O presente estudo pode afirmar que as cargas e o carregamento interferem na segurança dos esterilizadores por VH2O2. As IUF validadas dos esterilizadores, dos PPSs, dos sistemas de barreira estéril e das bandejas de acondicionamento devem ser respeitadas, como também a qualificação dos equipamentos com carga que representem um desafio da rotina utilizando-se IB em meio ciclo. Este procedimento pode detectar a insuficiência de exposição dos PPSs ao agente esterilizante para atender o Nível de Segurança de Esterilidade (SAL - Sterility Assurance Level) de 10-6 . Atualmente, o monitoramento de rotina de todos os ciclos com IB é o procedimento mais seguro para este método de esterilização.

Introduction: The recent advances in surgical techniques have required the use of low- temperature sterilization methods, such as vaporized hydrogen peroxide (VH2O2), to enable the sterilization of thermo-sensitive health care products. Although widely applied in Central Sterile Service Departments (CSSD), problems related to this technology are many such as: low diffusivity, lack of constructive and validation standards, technology limitation to measure the concentration of the sterilizing agent, cycle validation and monitoring, as well as inadequate loading and sterilization practices for health care products. Objective: Evaluating, through physical (PI) and biological (BI) indicators, whether the current practices of Central Sterile Service Departments, when choosing the load and the loading processes, interfere with the safety of VH2O2 sterilizers: Sterrad® 100S short cycle, Sterrad® 100NX standard cycle and Vpro® Max lumenless cycle. Method: Field, exploratory and descriptive research study performed in hospitals that use the aforementioned equipment in the working routine. Data were collected after approval by the Research Ethics Committee and authorization of the participating hospitals. Three sterilizers from each model and from different CSSD were evaluated, and the choice of cycles for data collection followed the criticality and frequency of use in the study sites. The BIs were unitarily positioned in double-Tyvek® (test-package) envelopes, with heat-sealing closure. In each sterilizer, a half-cycle no-loading test was performed, with three testing-packages in the following positions: upper/anterior; upper/center and lower/posterior. Subsequently, triplicate assays were performed with the same load, containing health care products that represent a routine challenge, also, in half cycle. BIs were added internally, in addition to two testing-packages, positioned in the upper/anterior and inferior/posterior area, the first placed at the point closest to the entrance of the sterilizing agent in the chamber, and the second at the farthest point. Results: For total of 9 assays with load from each sterilizers model, positive BIs 22% on assays in the 100S model test, 33% in the 100NX model and 100% in the V-pro model. The positive BIs were related to package overlapping; presence of magnetic mat; packaging trays, without the recommendations of the equipment manufacturers; and impaired diffusion of the VH2O2 sterilizing agent in the sterilization chamber, especially at points distant from the agent entrance. Other hypotheses that may have contributed to the result were the lack of IFU of the health care products for the method, as well as the use of additional mass consuming VH2O2. It was not possible to correlate the positive BI results to the physical parameters of the sterilizer, as well as to the total weight of the load. Conclusion: The current research study can conclude that the loads and the loading interfere in the safety of the sterilizers by VH2O2. The validated instructions for use of sterilizers manufacturers, health care products, sterile barrier systems and packaging trays must be respected, as well as the qualification of loading equipment, representing a challenge to the routine using BI in half cycle. This procedure can detect the insufficient exposure of health care products to the sterilizing agent to meet the Sterility Assurance Level (SAL) of 10-6 . Currently, routine monitoring of all cycles with BIs is the safest procedure for this sterilization method.

Application of vaporized hydrogen peroxide in field of disinfection / 医疗卫生装备

The vaporized hydrogen peroxide had its applicability, mechanism and generation mode introduced, and its application was analyzed in the hospitals, bio-safety labs and etc in foreign countries and China. It's pointed out that emphases in China had to be placed on vaporized hydrogen peroxide concentration real-time monitoring when used for disinfection.The relationship was determined between vaporized hydrogen peroxide concentration and disinfection effect,and the studies were carried out on domestic production and automation of the vaporized hydrogen peroxide equipment. The vaporized hydrogen peroxide was indicated to gain a brilliant application prospect in the field of disinfection.

Design and evaluation of a disinfection device for infant incubator terminal / 中国医学装备

Objective:To design Disinfection device of Infant incubator to address the existing infant incubator terminally sterilized in the presence of ultraviolet light disinfectant wipe and disinfection effect is not complete. Methods:Using vaporized hydrogen peroxide to kill spores of principle, to design a PLC and touch screen technologies such as infant incubator terminal disinfection device, mainly by vaporized hydrogen peroxide generator to accommodate infant incubator stainless steel tanks, gas communication piping, etc., through clean and dry after the infant incubator, pushed into stainless steel tanks, a key parameter set to start after the end of the introduction of the incubator to disinfection, disinfection by chemical and biological indicator discoloration indicator kill situation to judge. Results:The disinfection device for gas distribution, no disinfection dead, low-temperature sterilization effect is good and easy to verify, infant incubator for material compatibility, safe, reliable, easy to operate, chemical indicator from green to yellow, biological indicator Bacillus stearothermophilus cultured for 7 days, sterile growth. Conclusion:The device is easy to verify the sterilization effect, material compatibility, safety and reliability, reduce labor intensity in clinical neonatology and critical sections infant incubator terminal disinfection areas have higher promotion and application value.

Evaluation of vaporized hydrogen peroxide fumigation as a method for the bio-decontamination of the high efficiency particulate air filter unit / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To evaluate the performance of vaporized hydrogen peroxide (VHP) for the bio-decontamination of the high efficiency particulate air (HEPA) filter unit.</p><p><b>METHODS</b>Self-made or commercially available bioindicators were placed at designated locations in the HEPA filter unit under VHP fumigation. The spores on coupons were then extracted by 0.5 h submergence in eluent followed by 200- time violent knocks.</p><p><b>RESULTS</b>Due to the presence of HEPA filter in the box, spore recovery from coupons placed at the bottom of the filter downstream was significantly higher than that from coupons placed at the other locations. The gap of decontamination efficiency between the top and the bottom of the filter downstream became narrower with the exposure time extended. The decontamination efficiency of the bottom of the filter downstream only improved gently with the injection rate of H2O2 increased and the decontamination efficiency decreased instead when the injection rate exceeded 2.5 g/min. The commercially available bioindicators were competent to indicate the disinfection efficiency of VHP for the HEPA filter unit.</p><p><b>CONCLUSION</b>This assay developed can detect all 16 β-lactams demanded by the European Union (EU). The whole procedure takes only 45 min and can detect 42 samples and the standards with duplicate analysis.</p>