Bl. Laube et al., Targeting aerosol deposition in patients with cystic fibrosis - Effects ofalterations in particle size and inspiratory flow rate, CHEST, 118(4), 2000, pp. 1069-1076
Citations number
15
Categorie Soggetti
Cardiovascular & Respiratory Systems","Cardiovascular & Hematology Research
Study objective: To determine if aerosolized medications can be targeted to
deposit in the smaller, peripheral airways or the larger, central airways
of adult cystic fibrosis (CF) patients by varying particle size and inspira
tory flow rate,
Design: Randomized clinical trial,
Setting: Outpatient research laboratory,
Patients: Nine adult patients with CF.
Interventions: Patients inhaled an aerosol comprised of 3.68 +/- 0.04 mum s
aline solution droplets (two visits) or 1.01 +/- 0.2 mum saline solution dr
oplets (two visits) for 30 s, starting from functional residual capacity an
d breathing at a slow or faster inspiratory flow rate. On all visits, the s
aline solution was admired with the radioisotope Tc-99m, Immediately after
inhalation, a gamma camera recorded the deposition pattern of the radioaero
sol in the lungs, Deposition images were analyzed in terms of the inner:out
er zone (I:O) ratio, a measure of deposition in an inner zone (large, centr
al ah-ways) vs an outer zone (small airways and alveoli).
Measurements and results; For the 3.68-mum aerosol, I:O ratios averaged 2.2
9 +/- 1.45 and 2.54 +/- 1.48 (p > 0.05), indicating that aerosol distributi
on within the lungs was unchanged while breathing at 12 +/- 2 L/min vs 31 /- 5 L/min, respectively, For the 1.01-mum aerosol, I:O ratios averaged 2.0
9 +/- 0.96 and 3.19 +/- 1.95 (p < 0.05), indicating that deposition was pre
dominantly in the smaller airways while breathing at 18 <coproduct> 5 L/min
and in the larger airways while breathing at 38 +/- 8 L/min, respectively,
Conclusions: These results suggest that the targeted delivery of an aerosol
to the smaller, peripheral airways or the larger, central airways of adult
CF patients may be achieved by generating an aerosol comprised of approxim
ately 1.0-mum particles and inspiring from functional residual capacity at
approximately 18 L/min and similar to 38 L/min, respectively.