Clinical Pharmacy Department, Faculty of Pharmacy, Beni-suef University, Beni-suef, Egypt.
Clinical Pharmacology Department, Faculty of Medicine, Beni-suef University, Beni-suef, Egypt.
Respir Care. 2019 Dec;64(12):1508-1515. doi: 10.4187/respcare.06639. Epub 2019 Aug 6.
A new holding chamber was designed to be used with a vibrating mesh nebulizer to increase the total inhalable dose for patients. It facilitates intermittent and continuous nebulization as well as the optional supply of supplemental oxygen via a T-piece with a mouthpiece adapter. This study aimed to evaluate the effect of oxygen introduction in the new holding chamber on aerosol delivery using a vibrating mesh nebulizer.
The study was divided into 2 parts. First, the total inhalable dose of 1 mL of a respirable solution (nominal dose of 5,000 μg-salbutamol) was determined using a breathing simulator set to provide a tidal volume of 500 mL, a breathing frequency of 15 breaths/min, and an inspiratory:expiratory ratio of 1:1 for adults as a quiet-breathing pattern. Three experimental nebulizer setups were used: a vibrating mesh nebulizer with the holding chamber and oxygen set at 6 L/min, a vibrating mesh nebulizer with the holding chamber and no oxygen, and a vibrating mesh nebulizer with the T-piece. Aerodynamic particle size characterizations were determined using cooled Andersen cascade impaction at an inhalation flow of 15 L/min. Second, we performed an in vivo study involving 12 healthy non-smoking subjects (6 female) who were > 18 y old with an average FEV > 90% of predicted. Using normal tidal breathing, subjects inhaled 1 mL of nebulized salbutamol (5,000 μg) through the vibrating mesh nebulizer with the holding chamber with and without oxygen and through the vibrating mesh nebulizer with a T-piece. To analyze salbutamol content, urine samples were obtained 30 min after dosing as an index of lung deposition, and their urine was cumulatively collected for 24 h as an index of systemic absorption.
The holding chamber significantly increased the total inhalable dose or amount of salbutamol excreted in the first 30 min, as well as the amount of salbutamol excreted over a 24-h period compared to the dose received with the vibrating mesh nebulizer with a T-piece ( = .005, = .034, and = .02, respectively), and relatively decreased the mass median aerodynamic diameter, although the difference was not significant. However, when oxygen was introduced in the holding chamber, the total inhalable dose, or amount of salbutamol excreted in the first 30 min, significantly decreased compared to use without oxygen ( = .003, = .03 respectively). No significant difference was found between the vibrating mesh nebulizer with the holding chamber with oxygen and the vibrating mesh nebulizer with a T-piece.
The vibrating mesh nebulizer with a holding chamber and without oxygen resulted in much better aerosol delivery compared to vibrating mesh nebulizer with a holding chamber and with oxygen delivery and to the vibrating mesh nebulizer with a T-piece. The use of oxygen with the holding chamber significantly decreased aerosol delivery and its benefit, and recommended flow should be reevaluated.
为了增加患者的总可吸入剂量，设计了一种新的储雾室，与振动网孔式雾化器一起使用。它可以方便间歇和连续雾化，以及通过带咬嘴适配器的 T 型件可选地供应补充氧气。本研究旨在评估在新的储雾室内引入氧气对使用振动网孔式雾化器输送气溶胶的影响。
研究分为两部分。首先，使用呼吸模拟器确定 1 毫升可吸入溶液（名义剂量为 5000μg沙丁胺醇）的总可吸入剂量，呼吸模拟器设置为提供 500 毫升潮气量、15 次/分钟呼吸频率和 1:1 吸气:呼气比作为安静呼吸模式。使用了三种实验性的雾化器设置：带储雾室和 6 L/min 氧气的振动网孔式雾化器、带储雾室和无氧气的振动网孔式雾化器以及带 T 型件的振动网孔式雾化器。使用 15 L/min 的吸入气流通过冷却的 Andersen 级联撞击器进行空气动力学颗粒大小特征测定。其次，我们进行了一项涉及 12 名健康不吸烟的受试者（6 名女性）的体内研究，这些受试者年龄均>18 岁，平均 FEV 占预计值的>90%。使用正常的潮式呼吸，受试者通过带储雾室的振动网孔式雾化器吸入 1 毫升沙丁胺醇（5000μg），有或没有氧气，以及通过带 T 型件的振动网孔式雾化器吸入。为了分析沙丁胺醇含量，在给药后 30 分钟收集尿液样本作为肺部沉积的指标，并累积收集 24 小时的尿液作为全身吸收的指标。
与带 T 型件的振动网孔式雾化器相比，储雾室显著增加了总可吸入剂量或前 30 分钟内沙丁胺醇的排泄量，以及 24 小时内沙丁胺醇的排泄量（=.005，=.034，=.02，分别），并且相对降低了质量中值空气动力学直径，尽管差异不显著。然而，当在储雾室内引入氧气时，与不使用氧气相比，总可吸入剂量或前 30 分钟内沙丁胺醇的排泄量显著减少（=.003，=.03，分别）。带储雾室和带氧气的振动网孔式雾化器与带 T 型件的振动网孔式雾化器之间没有发现显著差异。
与带储雾室和带氧气输送的振动网孔式雾化器以及带 T 型件的振动网孔式雾化器相比，不带氧气的带储雾室的振动网孔式雾化器可实现更好的气溶胶输送。在储雾室内使用氧气会显著降低气溶胶输送及其益处，并且建议重新评估推荐流量。
