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 · s-1 (su 1.06; range 5.86-9.36 mg · s-1) for the NaF method and 7.27 mg · s-1 (SD 0.82; range 5.52-8.26 mg · s-1) for the LiCl method. The LiCl method had a coefficient of repeatability of 13 mg · s-1 compared with 3.7 mg · 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.

Item Type:	Refereed Article
Research Division:	Medical and Health Sciences
Research Group:	Cardiorespiratory Medicine and Haematology
Research Field:	Respiratory Diseases
Objective Division:	Health
Objective Group:	Clinical Health (Organs, Diseases and Abnormal Conditions)
Objective Field:	Respiratory System and Diseases (incl. Asthma)
Author:	Reid, DW (Dr David Reid)
Author:	Johns, DP (Associate Professor David Johns)
Author:	Walters, EH (Professor Haydn Walters)
ID Code:	35873
Year Published:	1998
Web of Science® Times Cited:	4
Deposited By:	Medicine (Discipline)
Deposited On:	2005-09-12
Last Modified:	2005-09-12
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