Bronchodilator therapy for patients who are hospitalized for acute exacerbations of COPD includes theophylline, inhaled p-sympathomimetic drugs, and often corticosteroids. Most commonly, inhaled bronchodilator drugs are administered to inpatients via gas-powered nebulizers. In contrast, MDIs, rather than nebulizers, are the standard method of delivery of inhaled (3-sympathomimetics for stable outpatients, as most studies have shown little or no advantage for therapy via a nebulizer. In patients whose condition is stable, equivalent bronchodilation is produced with a much smaller dose of medication when delivery is by MDI, rather than nebulizer.
Nevertheless, adequate technique is required if use of an MDI is to result in optimum retention of the drug in the lungs. Most authors have recommended that this consists of MDI actuation during a slow, deep inspiration followed by breath-holding for 10 s. This pattern is very difficult for patients with acute exacerbations of COPD, as they are usually quite dyspneic and tachypneic. Many patients have difficulty activating the MDI at the appropriate time. For these reasons, delivery of medication and its retention in the lungs may be suboptimal. Therefore, many practitioners have prescribed p-sympathomimetic administration via hand-held gas-powered nebulizers for patients hospitalized for acute exacerbations of COPD. These devices allow delivery of medication over many tidal breaths; however, in addition to the cost of the equipment for nebulization, respiratory therapists often administer these “breathing treatments,” adding to the cost of care. whitening gel
The use of spacer (reservoir) devices has been recommended for outpatients who have difficulty using MDIs. These devices eliminate the need for precise lung-hand coordination, result in decreased impaction of particles in the upper airway, and some allow rebreathing, making breath-holding less critical. Multiple studies have assessed the utility of these devices in stable COPD. Some have shown that spacers enhanced bronchodilation when used with MDIs; however, these devices probably offer little advantage if patients are able to use MDIs correctly. In contrast, the MDI-spacer system might be especially useful in the setting of an acute exacerbation of airflow obstruction.
Few studies have assessed the relative efficacy of an MDI or MDI-spacer and nebulizer systems in acute exacerbations of COPD. In one study the patients were not blinded to the method of active drug delivery. The recent double-blind study of Turner et al found M Di-spacer and nebulizer systems to be equally effective in improving spirometric data and reducing dyspnea in a group of patients with COPD treated with an intensive regimen in the emergency room. Patients were treated with metaproterenol every 30 minutes for three treatments with both devices, but active drug was randomly assigned to only one device, and no crossover limb was employed. We undertook a study to investigate the relative efficacy of nebulizer and MDI-spacer treatments with albuterol in patients hospitalized with acute exacerbations of COPD using a more typical inpatient schedule of drug administration with a randomized double-blind crossover protocol.