Barry P W, O'Callaghan C
Dept of Child Health, University of Leicester, UK.
Eur Respir J. 1998 Aug;12(2):463-6. doi: 10.1183/09031936.98.12020463.
The objective of this study was to determine whether current regulatory methods for assessing the output of nebulizers are appropriate for the delivery of nebulized steroid suspensions to patients. We studied a conventional jet nebulizer (the Intersurgical Cirrus), an open-vent nebulizer (the Medicaid Sidestream) and a breath-enhanced nebulizer (the Pari LC Plus), using a constant sampling flow or a sinusoidal pump to represent the breathing pattern of children from 6 months to adulthood. Recovery of budesonide released from the nebulizers onto filters was reduced when using breathing simulation compared with constant flow, and this reduction was greatest for the conventional nebulizer (Cirrus, 103 microg with constant flow to 4.4 microg with a 50 mL tidal volume; Pari, 176 microg to 25 microg). The open-vent nebulizer deposited very little budesonide on the filter at lower tidal volumes (4.5 microg with a 50 mL tidal volume), possibly because the enhanced flow of aerosol laden air was greater than the inspiratory flow from the breathing simulator. The output of the LC plus was reduced at high flow, from 176 microg at 20 L x min(-1) to 93 microg at 60 L x min(-1). Overall, the measured output varied by up to 700%, depending on the method used. These results suggest that breathing patterns dramatically alter the measured output of different nebulizers and that breathing simulation should be included as part of their assessment.
本研究的目的是确定当前评估雾化器输出量的监管方法是否适用于向患者输送雾化类固醇混悬液。我们研究了一种传统喷射雾化器（英特外科Cirrus）、一种开放式通气雾化器（医疗补助侧流雾化器）和一种呼吸增强型雾化器（帕里LC Plus），使用恒定采样流量或正弦泵来模拟6个月至成年儿童的呼吸模式。与恒定流量相比，使用呼吸模拟时从雾化器释放到滤器上的布地奈德回收率降低，传统雾化器（Cirrus，恒定流量时为103微克，潮气量50毫升时为4.4微克；帕里，176微克至25微克）的这种降低最为明显。在较低潮气量（50毫升潮气量时为4.5微克）下，开放式通气雾化器在滤器上沉积的布地奈德非常少，这可能是因为载有气溶胶的空气增强流量大于呼吸模拟器的吸气流量。LC plus在高流量时输出量降低，从20 L·min⁻¹时的176微克降至60 L·min⁻¹时的93微克。总体而言，根据所使用的方法，测量的输出量变化高达700%。这些结果表明，呼吸模式会显著改变不同雾化器的测量输出量，呼吸模拟应作为其评估的一部分。
