Chuffart A A, Sennhauser F H, Wildhaber J H
Department of Respiratory Medicine, University Children's Hospital, Zürich, Switzerland.
Swiss Med Wkly. 2001 Jan 12;131(1-2):14-8. doi: 10.4414/smw.2001.05897.
The main objective of this study was to compare the in vitro delivery of salbutamol from a chlorofluorocarbon(CFC)-propelled pressurised metered-dose inhaler (pMDI) versus a newly developed hydrofluoroalkane(HFA)-propelled pMDI through various spacers. In addition, we aimed to study the effect on bronchodilator response when using an optimal pMDI/spacer combination for aerosol delivery compared to a suboptimal combination.
Particle size distribution and output from salbutamol pMDIs containing either CFC propellants (Ventolin) or HFA propellants (Airomir) were measured using a multistage liquid impinger (MSLI) and compared to that through both detergent-coated (non-static) or untreated (static) large volume (Nebuhaler, Volumatic) and small volume (Aerochamber) plastic spacers. Flow-volume curves (FEV1) were obtained from twelve asthmatic children with known significant bronchodilator response (8 males), aged 13-17 years, randomly inhaling salbutamol from a CFC-pMDI through a static spacer (Nebuhaler) and from an HFA-pMDI through a non-static spacer (Nebuhaler).
In vitro output of particles in the respirable range (< 6.8 microns) from HFA-pMDIs was significantly higher than that from CFC-pMDIs using various spacers. Removal of electrostatic charge increased output from CFC- and HFA-pMDIs through all spacers by 17-82%. The mean (SD) bronchodilator response after inhalation of salbutamol from a CFC-pMDI through a static spacer was 7.1% (6.3%) compared to 17.5% (7.9%) after inhalation from an HFA-pMDI through a non-static spacer (p = 0.002).
Use of a newly developed HFA-propelled pMDI greatly improves drug delivery through spacers compared to a CFC-propelled pMDI. However, electrostatic charge in plastic spacers remains the key determinant limiting delivery of salbutamol from a pMDI through spacers, and can be reduced by soaking the spacer in a household detergent. Using an optimal pMDI/spacer combination leads to a significantly improved bronchodilator response.
本研究的主要目的是比较氯氟烃（CFC）推进的定量吸入气雾剂（pMDI）与新开发的氢氟烷烃（HFA）推进的pMDI通过各种储雾罐的沙丁胺醇体外递送情况。此外，我们旨在研究与次优组合相比，使用最佳pMDI/储雾罐组合进行气雾剂递送时对支气管扩张反应的影响。
使用多级液体冲击器（MSLI）测量含有CFC推进剂（万托林）或HFA推进剂（奥克斯都保）的沙丁胺醇pMDI的粒径分布和输出量，并与通过洗涤剂涂层（非静电）或未处理（静电）的大容量（耐保生、Volumatic）和小容量（爱全乐储雾罐）塑料储雾罐的情况进行比较。从12名已知有显著支气管扩张反应的哮喘儿童（8名男性）中获得流量-容积曲线（FEV1），这些儿童年龄在13至17岁之间，随机通过静电储雾罐（耐保生）从CFC-pMDI吸入沙丁胺醇，并通过非静电储雾罐（耐保生）从HFA-pMDI吸入沙丁胺醇。
使用各种储雾罐时，HFA-pMDI在可吸入范围内（<6.8微米）的颗粒体外输出量显著高于CFC-pMDI。去除静电荷使CFC-和HFA-pMDI通过所有储雾罐的输出量增加了17%-82%。通过静电储雾罐（耐保生）从CFC-pMDI吸入沙丁胺醇后的平均（标准差）支气管扩张反应为7.1%（6.3%），而通过非静电储雾罐（耐保生）从HFA-pMDI吸入后的反应为17.5%（7.9%）（p = 0.002）。
与CFC推进的pMDI相比，使用新开发的HFA推进的pMDI可大大改善通过储雾罐的药物递送。然而，塑料储雾罐中的静电荷仍然是限制沙丁胺醇从pMDI通过储雾罐递送的关键决定因素，可通过将储雾罐浸泡在家用洗涤剂中来减少。使用最佳pMDI/储雾罐组合可显著改善支气管扩张反应。
