@article {Berlinskirespcare.05782, author = {Ariel Berlinski and Dirk von Hollen and John N Pritchard and Ross HM Hatley}, title = {Delay Between Actuation and Shaking of a Hydrofluoroalkane Fluticasone Pressurized Metered-Dose Inhaler}, elocation-id = {respcare.05782}, year = {2017}, doi = {10.4187/respcare.05782}, publisher = {Respiratory Care}, abstract = {BACKGROUND: Inhaled corticosteroids are used to treat pediatric asthma. The shaking of a pressurized metered-dose inhaler (pMDI) is required to ensure consistency of emitted dose. Delays between shaking and actuating the pMDI are frequent during administration of aerosols to children where a valved holding chamber is used.METHODS: In a recent clinical trial, we used a monitoring device to record shaking and actuation of the pMDI and the inhalation profiles of children with asthma while they were inhaling fluticasone hydrofluoroalkane from a valved holding chamber onto an external filter. During the procedure, in vitro and transport samples were generated without a delay between shaking and actuating the pMDI. Emitted dose, expressed as percentage of ex-actuator nominal dose, obtained from the second actuation following a recorded shake-actuation interval for subjects and from in vitro/transport samples (no delay) were compared.RESULTS: The mean emitted dose was 158.6\% (95\% CI 150.1{\textendash}167.2\%) (subjects) and 106.8\% (95\% CI 104.7{\textendash}108.9\%) (in vitro + transport) of the ex-actuator nominal dose (P \< .001). The mean delay between shaking and actuating the pMDI was 12.9s (95\% CI 11.9{\textendash}13.9s) for the subject samples. A strong correlation was observed between shake and actuation delay and the emitted dose of the second actuation following the delay (Spearman correlation coefficient = 0.61). A 10-, 20-, and 30-s delay resulted in an emitted dose of the second actuation following the delay of 147, 187, and 227\% of the ex-actuator nominal dose, respectively.CONCLUSIONS: Delays between shaking and actuating a corticosteroid suspension pMDI resulted in an increase in the emitted dose of the second actuation following the delay. This can be a common occurrence when doses are administered by a caregiver to a patient via a holding chamber. This should be addressed by practitioners educating patients and parents on proper inhaler use.}, issn = {0020-1324}, URL = {https://rc.rcjournal.com/content/early/2017/11/21/respcare.05782}, eprint = {https://rc.rcjournal.com/content/early/2017/11/21/respcare.05782.full.pdf}, journal = {Respiratory Care} }