Proposta de padronização para aferição de equipamentos de fototerapia

Abstract

Objective: to propose a method to evaluate and maintain the efficiency of equipment commonly used in Brazil in order to obtain uniform results in phototherapy treatments in different services.Material and methods: the radiometer/photometer used to measure spectral irradiance is locally manufactured and fulfills basic requirements. Measure standardization seeks to be applicable and reproducible to phototherapy devices employed in Brazil. The material necessary for measurements can be easily assembled by the neonatology staff, except for the radiometer. We searched Medline for papers relevant to this review published throughout the last 10 years.Results: irradiance in phototherapy issues should be referred to as "medium spectral irradiance". We describe how to obtain medium spectral irradiance using fluorescent and halogen phototherapies.Comments: the components of a radiometer/photometer are described. This knowledge is fundamental to understanding sensibility variations and to justifying differences in irradiance when ranges of radiometer recording are a little different. The standardization of this device will certainly simplify the comparison between results in different services.We also analyzed characteristics of different equipment used in phototherapy that might interfere with their irradiance.J Pediatr (Rio J) 2001; 77 (2): 67-74: phototherapy, radiometry, equipment. ResumoObjetivo: propor método de avaliação e manutenção da eficiên-cia dos equipamentos mais comumente usados em nosso meio, de maneira a uniformizar os resultados obtidos em tratamentos fototerápicos por diferentes serviços.Material e métodos: o radiômetro/fotômetro utilizado na medida da irradiância espectral é de fabricação nacional e atende aos requisitos básicos indispensáveis. As padronizações de medida procuram ser facilmente aplicáveis e reprodutíveis aos aparelhos de fototerapia em uso no país. O material necessário às aferições, excetuando-se o radiômetro, pode ser facilmente confeccionado em qualquer serviço de neonatologia. Procuramos nos trabalhos publicados nos últimos 10 anos no Medline os pertinentes a esta revisão.Resultado: propõe-se que a irradiância relatada nos trabalhos de fototerapia seja fornecida como Irradiância Espectral Média e descreve-se como obtê-la, tanto em fototerapias com fontes fluorescentes como halógenas.Comentários: são descritos os componentes dos radiômetros/ fotômetros, cuja compreensão é importante para que possamos perceber variações na sensibilidade e diferenças significativas na irradância quando as faixas de leitura dos radiômetros são um pouco diferentes. A adoção de um tipo de equipamento padrão facilitaria muito a comparação de resultados obtidos por diferentes serviços. São ainda comentadas as características de diferentes equipamentos de fototerapia que podem interferir na mensuração da irradiância dos mesmos.J Pediatr (Rio J) 2001; 77 (2): 67-74: fototerapia, radiometria, equipamento. Proposta de padronização para aferição de equipamentos de fototerapia Standardizing the calibration...

Irradiance of phototherapy equipment in maternity wards in Maceió

“…These devices present an irradiance two to three times higher than that observed in devices with white bulbs (6,8) . This kind of bulb is not made in Brazil and its importation is hindered by administrative bureaucracy and high costs (9) .…”

“…There was a predominance of Bilispot ® 006-BP devices, which is evidenced by its dichroic configuration, in which only 40% of the value accompanies the light beam (6) . The device has irradiance above that emitted by the conventional type, but its distribution is irregular, which diminishes its efficacy in relation to the irradiance value.…”

“…The bilirrubin molecule absorbs visible light ranging from 400 and 500nm, with peaks around 460 nm (5) . Irradiance is considered the amount of energy emitted on a certain surface, by its unit of area (6) .…”

“…The conventional or common phototherapy uses from six to eight white fluorescent bulbs (day light) (6) ; some devices already have interspersed blue bulbs, at least two. The minimum irradiance of this device is 4mw/ cm 2 /nm (5)(6)(7)(8) .…”

“…The average therapy used was in accordance to each evaluated device. Aware that there is no consensus regarding values that would define phototherapy as efficient (6) , the following spectral averages were used as parameter: for the conventional type, the average was 4 mw/cm2/nm to 35cm from the newborn; for the Bilispot ® 006-BP type, the used average was 5 to 8 mw/cm2/nm to 50cm from the newborn and for the Bilitron type, the average of 10 mw/cm2/nm to 35cm from the newborn. arithmetic average of these nine portions is considered the average spectral irradiance, which the newborn under treatment is subject to (6) .…”