Clinical evaluation of the peak inspiratory flow generated by asthmatic children through the Novolizer

STUDY OBJECTIVE: To assess whether asthmatic children may generate sufficient peak inspiratory flow through the Novolizer, a novel multiple dose dry powder inhaler with acoustic and optical feedback mechanisms for correct inhalation. PATIENTS AND METHODS: 137 children (median age 7 years, range 4-2) with mild to moderate persistent asthma (FEV1 < 90% predicted or pre-treated with low-dose steroids) participated in this open, multi-centre study. After assessment of FEV1 and peak inspiratory flow (without inhalator device, PIF), the children were instructed to inhale with the Novolizer (PIF through inhaler, PIF-N). All assessments were done in triplicate and the mean out of three attempts analysed. RESULTS: Mean PIF was 128 +/- 61 l/min and mean PIF-N was 69 +/- 18 l/min. This is distinctly above the rate necessary to overcome the Novolizer's trigger threshold. PIF performance through the Novolizer was linear in the age interval of 4-8 years, no further increase was observed beyond 8 years. CONCLUSIONS: The medium to low intrinsic resistance of the Novolizer permits a relatively high PIF through this device. Together with the feedback mechanisms, this makes the Novolizer particularly valuable for inhalation therapy in asthmatic children with drugs such as salbutamol, formoterol, or budesonide.