Metered-dose inhalers and nebulizers in the acute setting

This article evaluates the current literature comparing beta-adrenergic agonists administered via metered-dose inhalers (MDIs) with nebulizer devices in adult and pediatric patients. These studies focus on the acute treatment of asthma or chronic obstructive pulmonary disease in the emergency department and other acute care settings.

English-language journal articles published between 1980 and 1991.

Eight studies that compared beta-adrenergic agonists administered via an MDI or an MDI with a spacing device versus a nebulizer were identified. All of the studies were either poorly designed or had few subjects. By consensus of the authors, all were included in the review.

Studies were assessed according to methodologic strength (e.g., prospective, comparative).

Five studies found no differences between administration methods, one study found metered-dose inhalation to be superior, and another found nebulization to be superior based on observed improvements in pulmonary function tests. There were no significant differences in adverse-reaction rates. When surveyed, subjects preferred MDIs to nebulizers. There were marked variations in doses administered within and between studies. There was no consideration given to doses potentially delivered to the lungs.

There is no significant difference between nebulizers and MDIs plus a spacer with regard to the administration of beta-agonists in the treatment of acute asthma. There are insufficient data to conclusively support the role of spacers in this setting. The choice of a specific delivery method at this time must be determined on an individual basis, taking into account the issues of cost, timeliness of administration, and personnel availability.