Ability of preschool children to use dry powder inhalers as evaluated by In-Check Meter

Background: Although current guidelines recommend the pressurized metered-dose inhaler with a spacer for preschool children with asthma, dry powder inhalers (DPI) may be a valuable treatment alternative. Methods: To evaluate the ability of preschool children to inhale through DPI, peak inspiratory flow rates (PIFR) of 57 healthy children aged 3-6 years were measured with In-Check Meter after practising with an instructor. Two different calibrated resistances were attached to the Meter to mimic the internal resistance of each inhaler; Diskus and Turbuhaler. Results: The ability of children to generate adequate inspiratory flow increased with age. The percentages of the 3-, 4-, 5-, and 6-year-old children who were able to inhale reliably through the devices were 30% (3/10), 79.0% (15/19), 100% (16/16), and 100% (12/12), respectively. In these children, 100%, 93.3%, 100%, and 100% achieved an adequate PIFR for the Diskus (30 L/min). In contrast, 66.7%, 66.7%, 62.5%, and 91.7% generated an adequate PIFR for the Turbuhaler (60 L/min). Conclusions: The In-Check Meter is a useful device to assess the ability of preschool children to generate adequate PIFR for each inhaler. Most children aged ≥5 years could use DPI.