Comparison of waste anesthetic gases in operating rooms with or without an scavenging system in a Brazilian University Hospital / Comparação de resíduos de gases anestésicos em salas de operação com ou sem sistema de exaustão em hospital universitário brasileiro

Abstract Background and objectives Occupational exposure to waste anesthetic gases in operating room without active scavenging system has been associated with adverse health effects. Thus, this study aimed to compare the trace concentrations of the inhalational anesthetics isoflurane and sevoflurane in operating room with and without central scavenging system. Method Waste concentrations of isoflurane and sevoflurane were measured by infrared analyzer at different locations (near the respiratory area of the assistant nurse and anesthesiologist and near the anesthesia station) and at two times (30 and 120 min after the start of surgery) in both operating room types. Results All isoflurane and sevoflurane concentrations in unscavenged operating room were higher than the US recommended limit (2 parts per million), regardless of the location and time evaluated. In scavenged operating room, the average concentrations of isoflurane were within the limit of exposure, except for the measurements near the anesthesia station, regardless of the measurement times. For sevoflurane, concentrations exceeded the limit value at all measurement locations and at both times. Conclusions The exposure to both anesthetics exceeded the international limit in unscavenged operating room. In scavenged operating room, the concentrations of sevoflurane, and to a lesser extent those of isoflurane, exceeded the recommended limit value. Thus, the operating room scavenging system analyzed in the present study decreased the anesthetic concentrations, although not to the internationally recommended values.

Resumo Justificativa e objetivos A exposição ocupacional aos resíduos de gases anestésicos em salas de operação (SO) sem sistema ativo de exaustão tem sido associada a efeitos adversos à saúde. Assim, o objetivo do estudo foi comparar os resíduos dos anestésicos inalatórios isoflurano e sevoflurano em SO com e sem sistema de exaustão. Método Concentrações residuais de isoflurano e sevoflurano foram mensuradas por analisador infravermelho em diferentes locais (próximo à área respiratória do auxiliar de enfermagem e do anestesiologista e próximo à estação de anestesia) e em dois momentos (30 e 120 min após o início da cirurgia) em ambos os tipos de SO. Resultados Todas as concentrações de isoflurano e sevoflurano nas SO sem sistema de exaustão foram mais elevadas em relação ao valor limite recomendado pelos EUA (2 partes por milhão), independentemente do local e momento avaliados. Nas SO com sistema de exaustão, as concentrações médias de isoflurano ficaram dentro do limite de exposição, exceto para as mensurações próximas à estação de anestesia, independentemente dos momentos avaliados. Para o sevoflurano, as concentrações excederam o valor limite em todos locais de medição e nos dois momentos. Conclusões A exposição a ambos os anestésicos excedeu o limite internacional nas SO sem sistema de exaustão. Nas SO com sistema de exaustão, as concentrações de sevoflurano, e em menor extensão, as de isoflurano excederam o valor limite recomendado. Dessa forma, o sistema de exaustão das SO analisado no presente estudo diminuiu as concentrações dos anestésicos, embora não tenha reduzido a valores internacionalmente recomendados.

Effect of laurus nobilis L. essential oil and its main components on alpha-glucosidase and reactive oxygen species scavenging activity

The present study was designed to determine the effects of the essential oil of Laurus nobilis L. [Lauraceae] and its three main components on alpha-glucosidase and reactive oxygen species scavenging activity. The chemical composition of the essential oil from Laurus nobilis L. leaves was analyzed by GC/GC-MS and resulted in the identification of 29 compounds, representing 99.18% of the total oil. 1,8-cineole [68.82%], 1-[S]-alpha-pinene [6.94%], and R-[+]-limonene [3.04%] were determined to be the main components. The antioxidant features of the essential oil and its three main components were evaluated using inhibition of 2,2-diphenyl-1-picrylhydrazyl, hydroxyl, and superoxide radicals, inhibition of hydrogen peroxide and lipid peroxidation assays. The results show that the DPPH, hydroxyl, and superoxide radical as well as hydrogen peroxide scavenging activities of the essential oil are greater than the positive controls and the three main components of the oil when tested independently. The inhibition of lipid peroxidation by the oil occurred less frequently than with 1,8-cineole and R-[+]-limonene alone, but the effects were more pronounced than those seen with 1-[S]-alpha-pinene and the positive controls. An alpha-glucosidase inhibition assay was applied to evaluate the in-vitro antidiabetic activity of the essential oil. IC[50]-values were obtained for laurel essential oil, 1, 8-cineole, 1-[S]-alpha-pinene, and R-[+]-limonene: 1.748 micro L/mL, 1.118 micro L/mL, 1.420 micro L/mL and 1.300 micro L/mL, respectively. We also found that laurel essential oil and 1, 8-cineole inhibited the alpha-glucosidase competitively while 1-[S]-alpha-pinene and R-[+]-limonene were uncompetitive inhibitors

Introduces a novel scavenger for waste anesthetic gas / 中国医疗器械杂志

This article introduces a novel scavenger for waste anesthetic gas which makes use of negative pressure in operating room. This setting can scavenge the exhaust gas absolutely without affection the normal work of anaesthesia.

A survey of the anesthesia scavenging systems in a teaching hospital.

Pollution by anesthetic gases can be a problem in operating theaters. More than 90 per cent of this pollution can be reduced by using a scavenging system. Such systems increase the complexity, and thus the hazards of administering anesthesia. A case of pneumothorax prompted an investigation of the active scavenging systems currently used in a teaching hospital by using a pre-use check up protocol. Thirty-eight closed-reservoir active scavenging systems were included. Ten systems (26.3%) were assembled incorrectly. All systems passed a negative pressure relief valve test. Seventeen systems (44.7%) failed to pass a positive pressure relief valve test because high pressure (over 10 cmH2O) developed during an O2 flush, but direct measurement of the pressure at the scavenging interface revealed that these defects were caused by a problem with the adjustable pressure limiting (APL) valves, not with the positive pressure relief valves of the system. We suggest that routine pre-use check up together with regular maintenance of equipment should be emphasized and all personnel should be encouraged to learn more about safety precautions.

Evaluación química de un sistema de extracción de gases anestésicos residuales para el control de la contaminación en salones de operaciones / Chemical evaluation of a system for the extraction of residual anesthetic gases to control pollution in operating rooms

Se estudia la eficiencia de un sistema de extracción local de gases anestésicos residuales el cual fue propuesto con la finalidad de controlar, mediante un método sencillo y económico, la contaminación por este tipo de sustancias en los salones de operaciones del país

Uso del Sistema de ventilación BAIN: Hospital Antonio Lenin Fonseca Martínez / System use of BAIN ventilation: Hospital Antonio Lenin Fonseca Martínez

Se realizó estudio prospectivo, descriptivo en 29 pacientes sometidos a anestesia general ventilados con sistema BAIN, alimentado a flujos de gases frescos de 70 y 80 ml/kg/min. para ventilación controlado y 100 ml/kg/min. Para ventilación expontánea. Se realizarón mediciones de gases arteriales en los periódos pre y transanestésicos, por medio de esto se analizaron los estados A/B de cada paciente de acuerdo a valores normales, relacionándose ambos períodos de anéstesia y comparandose los resultados en los diferentes flujos usados....