Relative lung deposition of salbutamol following inhalation from a spacer and a Sidestream jet nebulizer following an acute exacerbation

BACKGROUND Studies comparing inhalation methods in acute exacerbations have not assessed lung deposition. METHODS Five 100-mu g salbutamol doses were inhaled from a metered dose inhaler plus spacer (MDI + SP) and 5 mg was nebulized (NEB) following acute exacerbation hospitalization. Urinary salbutamol excretion was determined at 30 min (USAL0.5) and over 24 h (USAL24) postinhalation together with forced expiratory volume in 1 s (FEV1). RESULTS The USAL0.5 mean ratio (90% confidence interval) post MDI + SP and NEB [n = 19 asthma, 11 chronic obstructive pulmonary disease (COPD)] was 1.01 (0.81, 1.26). USAL24 was less (P < 0.001) following MDI + SP, whereas FEV1 was similar. Only a small difference between asthmatics and COPD patients was observed for the MDI + SP in that the USAL0.5 was higher in the asthmatics for the spacer method. CONCLUSION The relative lung deposition after inhaling 500 mu g salbutamol from MDI + SP is similar to 5 mg from a Sidestream nebulizer following an acute exacerbation.