Purpose: To quantify distribution of albuterol aerosol generated by a pneumatic nebulizer within the nose and lungs of a model of a 9-month-old child (SAINT) and aerosol loss to the environment, during simulated breathing at increasing tidal volumes (TVs).
Methods: (99m)technetium-labeled albuterol aerosol was generated by an IPI nebulizer with face-mask. Deposition was quantified as a percentage of emitted dose using gamma scintigraphy.
Results: Lung deposition was similar for all TVs, averaging 7.17 +/- 0.01%, 9.34 +/- 0.01% and 9.41 +/- 0.02% at 50, 100 and 200 mL TV, respectively. In contrast, nose deposition increased significantly with TV, averaging 4.40 +/- 0.02%, 11.39 +/- 0.02% and 22.12 +/- 0.02% at 50 mL, 100 mL and 200 mL TV, respectively (all p < 0.0167). Aerosol loss to the environment was significantly lower at 200 mL TV (53.81 +/- 0.04%), compared to 50 mL (71.99 +/- 0.02%) (p < 0.0167).
Conclusions: Our results suggest that nasal deposition of albuterol aerosol generated by a pneumatic nebulizer in 9-month-old infants may be significantly affected by changes in TV, ranging between 50 to 200 mL, whereas total lung deposition may not be affected. These results also predict that environmental losses would be highest when administering to a child breathing at 50 mL TV. These data should be useful to companies who are working to improve aerosol delivery systems to treat infants.