Aerosol drug delivery to the lungs during nasal high flow therapy: An in vitro study

Research output: Contribution to journalJournal articleResearchpeer-review


  • Martin Wallin
  • Patricia Tang
  • Rachel Yoon Kyung Chang
  • Yang, Mingshi
  • Warren H. Finlay
  • Hak Kim Chan

Background: Aerosol delivery through a nasal high flow (NHF) system is attractive for clinicians as it allows for simultaneous administration of oxygen and inhalable drugs. However, delivering a fine particle fraction (FPF, particle wt. fraction < 5.0 μm) of drugs into the lungs has been very challenging, with highest value of only 8%. Here, we aim to develop an efficient nose-to-lung delivery system capable of delivering improved quantities (FPF > 16%) of dry powder aerosols to the lungs via an NHF system. Methods: We evaluated the FPF of spray-dried mannitol with leucine with a next generation impactor connected to a nasopharyngeal outlet of an adult nasal airway replica. In addition, we investigated the influence of different dispersion (20-30 L/min) and inspiratory (20-40 L/min) flow rates, on FPF. Results: We found an FPF of 32% with dispersion flow rate at 25 L/min and inspiratory flow rate at 40 L/min. The lowest FPF (21%) obtained was at the dispersion flow rate at 30 L/min and inspiratory flow rate at 30 L/min. A higher inspiratory flow rate was generally associated with a higher FPF. The nasal cannula accounted for most loss of aerosols. Conclusions: In conclusion, delivering a third of inhalable powder to the lungs is possible in vitro through an NHF system using a low dispersion airflow and a highly dispersible powder. Our results may lay the foundation for clinical evaluation of powder aerosol delivery to the lungs during NHF therapy in humans.

Original languageEnglish
Article number42
JournalBMC Pulmonary Medicine
Issue number1
Publication statusPublished - 15 Feb 2019

    Research areas

  • Aerosol, Inhalable drugs, Lungs, Nasal cannula, Nasal high flow, Powders, Pulmonary disease, chronic obstructive

Number of downloads are based on statistics from Google Scholar and

No data available

ID: 221825339