Twenty patients admitted through the emergency room to medical wards for an acute exacerbation of COPD were studied. One additional subject was recruited for the study but was excluded when he was unable to perform adequate spirometry. All patients had a long history of chronic airflow obstruction and cigarette smoking. Patients with acute respiratory acidosis (pH<7.30) were excluded. Subjects were studied within 24 h of admission to the hospital. The project was approved by our institutional review board for human studies, and informed written consent was obtained from each subject prior to initiation of the study. generic zoloft
Standard therapy included intravenous aminophylline, intravenous corticosteroids, and inhaled or oral sympathomimetics. Such therapy was left to the discretion of the primary-care physicians. Inhaled bronchodilator therapy and oral p-adrenergic agonists were withheld for 4 h before starting the study, and for the next 8 h, no nonprotocol sympathomimetics were allowed.
Subjects were instructed in the use of a spacer (InspirEase). This is a 700-ml collapsible reservoir-bag device fitted with a reed that vibrates if inspiratory flow exceeds 0.3 L/s.- Subjects were instructed to inflate the bag, discharge the MDI into the bag, and then inhale slowly from the spacer so that the reed did not make a sound until the reservoir bag was empty. They then held their breath for 5 s, exhaled into the bag, and inhaled slowly again, followed by 5 s of breath-holding. Nebulizer therapy was administered via a nebulizer (Airlife Misty Nebulizer) powered by compressed air at a flow rate of 6 to 8 L/min.
An outline of the protocol is illustrated in Figure 1. In each treatment block, subjects first received four puffs of albuterol (0.36 mg) or placebo via the MDI-spacer as follows: puff 1 —► (one minute) —► puff 2 —> (five minutes) —> puff 3 —> (one minute) —► puff 4. After a five-minute period, either albuterol (2.5 mg) or placebo (2.5 ml of physiologic saline solution) was administered via the nebulizer over 10 to 15 minutes. Four hours after starting the nebulizer therapy, the process was repeated (treatment block 2). Administration by MDI-spacer and nebulizer, in that order, was used for each treatment block, but active drug was administered by only one device. Active drug was administered by the alternate device in the second treatment block. The order with which active drug was given by MDI-spacer (first or second treatment block) was randomized. Order-1 patients received active drug by MDI-spacer in treatment block 1 and nebulizer in treatment block 2.
Figure 1. Schematic of protocol. Treatment blocks 1 and 2 were separated by 4 h. ALB, Albuterol.