Improved efficacy of aerosol delivery to distal  [ Return towards  Scientific information  ]

Wednesday, 14th June 2006

STUDY ACCEPTED AND PRESENTED AT THE 25TH CONGRESS OF EAACI (European Academy of Allergology and Clinical Immunology); Vienna, 10-14 June 2006

Improved efficacy of aerosol delivery to distal airways in paediatric subjects using a new spacer mouth-mask

AUTHORS

Luigi Di Berardino (Paediatrician and Allergologist, Milan); Hasan Yüksel (Dept. of Paediatric Allergy, Celal Bayar University, Turkey); Zeynep Burak and Diydem Yüksel (Dept. of Nuclear Medicine, Ege University, Turkey)

INTRODUCTION

Aerosol therapy is a method that has been used for over fifty years to treat respiratory diseases. Although it is applied using different methods and means, the devices used for delivering steroids and bronchodilatators can all be considered equally efficient.
The aim of this study was to compare the efficacy of a conventional mask and that of a new spacer mouth-mask (Nebula, Markos Mefar S.p.A.).

METHOD

Six healthy subjects without evident respiratory disease were included in the study.
The first group initially performed aerosol inhalation using a traditional face-mask and then, one week later, using the new spacer mouth-mask.
A conventional mask was used in the first stage, and the test was repeated a week later using a spacer mouth-mask.
One 2-ml dose saline solution containing 20 Mci of 99mTc-DTPA - acid diethylenetriamine-pentaacetic (Amersham) was administered to volunteers undergoing one-minute aerosol therapy with spontaneous current volume respiratory pattern.
Initially a series of scintigraphic front/rear ventilation images was obtained to determine aerosol deposition in the oropharynx and lungs.
Since the study last only 12 minutes, there was no need to calculate the 99mTc half-life.

RESULT

As shown in the images, oropharyngeal deposition was less (432 ± 158 vs 370 ± 37 cpm, p < 0.05) using the new spacer mouth-mask, and peripheral lung deposition was greater (690 ± 120 vs 965 ± 89 cpm p <0.001).

CONCLUSIONS

This result appears to confirm the efficacy of the spacer mouth-mask in short-term aerosol therapy.
The resulting effect is probably due to the rate of atomisation (1.2 ± 0.2 vs 0.4 ± 0.1 m/sec), as stated by the manufacturers.
In the past, the efficacy of MDIs was improved by using a spacer. Today, this new mask and recently gained knowledge of the efficacy of short-term treatment allow the spacer mouth-mask to be used instead of the old spacer.