The effect of breathing frequency on deposition of drug aerosol using an inhalation‐synchronized dosimeter in healthy adults

Abstract

The deposition of inhaled drug aerosol between the tongue, the upper and lower respiratory tract, the lungs and the gastrointestinal tract (GI tract) in 11 healthy adults was studied by using a nebulizer with an inhalation-synchronized dosimeter. The effect of breathing frequency on deposition was studied using radioaerosol (mixture of salbutamol and technetium bound to diethylenetriamine pentacetate, [99mTc]DTPA) and a gamma-camera. In healthy subjects who were breathing at their own frequency (16 +/- 5 breaths min-1, mean +/- SD), the proportion of inhaled aerosol deposited in the lungs was 48 +/- 14 (mean percentage +/- SD). The proportion deposited in the upper airway tract and the GI tract was 19 +/- 13 and 25 +/- 9 respectively, and the remainder was deposited on the tongue (6 +/- 4) and in the lower airway tract (3 +/- 2). Guided, slower breathing frequency (11 +/- 5 breaths min-1) changed the deposition remarkably. The proportion of the pulmonary deposition of the inhaled dose increased significantly (P < 0.004) to 60 +/- 17, and the proportion of the upper airway tract deposition decreased significantly (P < 0.005) by half of the initial deposition. We conclude that a slow controlled breathing frequency is an important factor if we want to increase the drug deposition in the lungs. It is also essential in decreasing the variation in the deposition of the lungs.

Comparison of Lung Deposition in Two Types of Nebulization

“…At variance with previous data from the literature, 25 we did not observe a relationship between RF and IPD with either device. This may be due to interindividual anthropometric variability and to the small number of volunteers studied.…”

Contemporary Formulation Development for Inhaled Pharmaceuticals

“…63e65 In a study using a jet nebuliser, it has been shown in human adults that, compared to their own breathing frequency (16 ± 5 breaths per minute), slower guided breathing (11 breaths per minute) increased pulmonary deposition significantly. 66 In another study, the significance of breath-hold time was studied in COPD patients. 67 The study compared the lung dose of six commercial inhalers after no breath-hold and a breath-hold of 5 s and 25 s. The lung dose was enhanced by as much as 26% and 53% after a breath-hold of 5 s and 25 s, respectively.…”

Mucoviscidose et traitements inhalés : quoi de neuf en 2013 ?

“…L'idée n'est pas nouvelle puisque des nébuliseurs adaptatifs, tel Halolite, ont déjà existé dans le passé. On sait depuis longtemps que la fréquence respiratoire et le volume inspiratoire influencent le dépôt pulmonaire [3][4][5][6]. En effet, celui-ci peut être multiplié par cinq en augmentant le volume inspiratoire [5,6].…”