Objective: To determine the efficacy of a metered-dose inhaler (MDI) with a large spacer device as compared to nebulized wet aerosols in the treatment of an unselected population with severe airflow limitation.
Design: Randomized, double blind, placebo-controlled trial.
Setting: University Hospital Department of Emergency Medicine (DEM).
Patients: Fifty patients, referred to the DEM between October 1, 1994 and March 31, 1995 with a severe, acute obstructive pulmonary event. Thirteen patients were diagnosed as having COPD; 37 patients were diagnosed as having asthma.
Intervention and results: Patients received either placebo MDI through a 750-mL cone-shaped spacer (Glaxo) [2 puffs] and nebulized salbutamol aerosol 0.5 mL in 1.5 mL saline solution (group 1, n=25) or salbutamol MDI and 0.5 mL saline solution in 1.5 mL saline solution administered in the same manner as above (group 2, n=25). The above treatment was repeated three times every 15 min, unless side effects appeared. Upon enrollment into the study, the FEV1 in group 1 was 0.78±0.7 L (mean±SD), 32% of predicted, and in group 2, 0.74±0.51 L, 29% of predicted (p=0.83). The FEV1 values after the first, second, and third interventions were as follows: in group 1, 1.18±0.99 L, 1.40±0.8, and 1.47±0.79, respectively, and in group 2, 1.17±0.99 L, 1.46±1.01, and 1.54±0.79 (p=0.83, 0.36, and 0.48, respectively). We observed no difference in spirometric measurements between the two groups at any time.
Conclusion: Even in the setting of the unselected group of patient referrals to the DEM for episodes of severe airflow limitation, the clinical and the objective bronchodilator responses to the administration of salbutamol are independent of the method of delivery: MDI with a large spacer vs aerosol nebulization.