Abstract:
:Modelling of inhaled particle deposition in the lungs potentially offers data relevant to assessing hazards from toxic inhaled particles, to studying mucus clearance or lung permeability by aerosol techniques, and to achieving better utilisation of drugs administered as aerosols. Analysis of published modelling studies is complicated by differing approaches to the quantitative estimation of physical factors determining deposition and by differing choices of anatomical data. Published formulae for predicting aerosol particle impaction are compared by applying them to the deposition of 5 micron particles in the human conducting airways using the morphological data of Weibel together with information from other sources about airways branching angles. The results indicate the range of deposition estimates that may be obtained from currently available impaction formulae. All but one of the formulae considered agree in indicating maximum deposition by impaction in, or close to, the segmental or subsegmental bronchi. Data are presented to indicate how the principal physical determinants of deposition depend on particle size, inhalation flow rate and lung volume during inhalation.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Agnew JE,Pavia D,Clarke SWdoi
10.1088/0031-9155/29/7/001subject
Has Abstractpub_date
1984-07-01 00:00:00pages
767-77issue
7eissn
0031-9155issn
1361-6560journal_volume
29pub_type
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