Dose-response to salbutamol via a novel palm sized nebuliser (Aerodose(R) Inhaler), conventional nebuliser (Pari LC Plus) and metered dose inhaler (Ventolintrade mark Evohalertrade mark) in moderate to severe asthmatics.

摘要

Aims The Aerodose(R) inhaler is a novel, palm-sized, breath actuated device which requires little patient coordination. This study compared the dose-response of salbutamol delivered by the Aerodose(R) Inhaler (Aerogen Inc., Mountain View, USA) vs Pari LC Plus jet nebulizer (Pari LC Plus; Pari GmbH, Starnberg, Germany) and Ventolintrade mark Evohalertrade mark HFA pMDI (Evohaler; Allen & Hanburys [GlaxoSmithkline], Uxbridge, UK). Methods Twenty-two moderate to severe asthmatic patients, mean (s.d.) age: 44.7 (9.4), FEV(1): 58.1 (12.0), received 4 cumulative doubling doses of salbutamol in a randomised, investigator blind, balanced crossover design. Spirometry and systemic safety variables (heart rate, blood pressure, T wave amplitude, QTc interval and potassium) were measured at baseline and after each dose. Results Parallel regression analysis revealed that microgram relative potency ratios for the Aerodose(R) Inhaler to be five times more efficient for FEV(1) than either the Pari LC Plus (0.202, 90% CI: 0.189-0.216) or the Evohaler (0.202, 90% CI: 0.189-0.216), while there was no difference between Pari LC Plus vs Evohaler. Similarly, Aerodose(R) Inhaler vs. Pari LC Plus showed approximately five-fold greater potency for all systemic parameters, except blood pressure. As compared to the Evohaler, Aerodose(R) Inhaler had equivalent potency for plasma potassium and T wave amplitude, but demonstrated greater potency for heart rate and QT(c) interval. Conclusions This study has indicated therefore, that Aerodose(R) Inhaler is approximately five times as efficient as the Pari LC Plus and Evohaler in relative lung delivery of salbutamol in moderate to severe asthmatics.