Ward R J, Reid D W, Leonard R F, Johns D P, Walters E H
Dept of Respiratory Medicine, Alfred Hospital and Monash Medical School, Melbourne, Victoria, Australia.
Eur Respir J. 1998 Apr;11(4):937-41. doi: 10.1183/09031936.98.11040937.
Conventional gravimetric (weight loss) calibration of jet nebulizers overestimates their aerosol output by up to 80% due to unaccounted evaporative loss. We examined two methods of measuring true aerosol output from jet nebulizers. A new adaptation of a widely available clinical assay for lithium (determined by flame photometry, LiCl method) was compared to an existing electrochemical method based on fluoride detection (NaF method). The agreement between the two methods and the repeatability of each method were examined. Ten Mefar jet nebulizers were studied using a Mefar MK3 inhalation dosimeter. There was no significant difference between the two methods (p=0.76) with mean aerosol output of the 10 nebulizers being 7.40 mg x s(-1) (SD 1.06; range 5.86-9.36 mg x s(-1)) for the NaF method and 7.27 mg x s(-1) (SD 0.82; range 5.52-8.26 mg x s(-1)) for the LiCl method. The LiCl method had a coefficient of repeatability of 13 mg x s(-1) compared with 3.7 mg x s(-1) for the NaF method. The LiCl method accurately measured true aerosol output and was considerably easier to use. It was also more repeatable, and hence more precise, than the NaF method. Because the LiCl method uses an assay that is routinely available from hospital biochemistry laboratories, it is easy to use and, thus, can readily be adopted by busy respiratory function departments.
由于未考虑蒸发损失，传统的喷射雾化器重量法（失重法）校准会使其气溶胶输出量高估多达80%。我们研究了两种测量喷射雾化器真实气溶胶输出量的方法。将一种广泛应用的锂临床检测方法（通过火焰光度法测定，LiCl法）的新改进方法与一种基于氟化物检测的现有电化学方法（NaF法）进行了比较。考察了两种方法之间的一致性以及每种方法的重复性。使用Mefar MK3吸入剂量计对10台Mefar喷射雾化器进行了研究。两种方法之间无显著差异（p = 0.76），10台雾化器的平均气溶胶输出量，NaF法为7.40 mg x s(-1)（标准差1.06；范围5.86 - 9.36 mg x s(-1)），LiCl法为7.27 mg x s(-1)（标准差0.82；范围5.52 - 8.26 mg x s(-1)）。LiCl法的重复性系数为13 mg x s(-1)，而NaF法为3.7 mg x s(-1)。LiCl法能准确测量真实的气溶胶输出量，且使用起来要容易得多。它也比NaF法更具重复性，因此更精确。由于LiCl法使用的检测方法医院生化实验室常规可得，所以易于使用，因此忙碌的呼吸功能科可以很容易地采用。
