Lung delivery of salbutamol by dry powder inhaler (Turbuhaler®) and small volume antistatic metal spacer (Airomir® CFC-free MDI plus NebuChamber®)

Abstract

As a worldwide ban on the use of chlorofluorocarbons (CFCs) in inhaler devices approaches, considerable attention has been focused on the production of CFC-free delivery devices. The aim of our study was to compare the delivery of salbutamol by dry powder inhaler (DPI), Turbuhaler® and a CFC- free metered-dose inhaler (MDI), Airomir®, used with a novel small volume metal spacer (NebuChamber®). Ten healthy volunteers, mean (SEM) age 21 (0.7) yrs were studied in a randomized, single (investigator)-blind cross-over design. Single doses of 1,200 μg salbutamol, from Turbuhaler® DPI and Airomir® CFC-free MDI via a NebuChamber®, were given as 12 sequential 100 μg inhalations over 6 min. The lung delivery of salbutamol was assessed by measuring the plasma salbutamol profile over the first 20 rain after inhalation. Plasma salbutamol concentration was expressed as maximal (Cmax) and average (Cav) value. Significant differences (p<0.001) were found between the NebuChamber® (N) and the Turbuhaler® (T) for salbutamol Cmax and Cav. This amounted to a 1.89 fold difference (95% CI 1.56-2.22) between these devices for Cmax, and a 1.78 fold difference (95% CI 1.42-2.15) for Cav. We have demonstrated that, in vivo, salbutamol from a chlorofluorocarbon-free metered-dose inhaler given via a small volume metal spacer (NebuChamber®) produces significantly greater delivery than from an efficient dry powder inhaler (Turbuhaler®).