One of these two subjects was also using inhaled corticosteroids. One subject was taking only an inhaled p-agonist, and a second subject was taking only oral terbutaline. In all of the subjects, there was documented acute onset of increasing respiratory distress. This was manifested by the short duration of symptoms: cough, 4.7 ±2.1 days; overt wheeze, 2.5 ±0.9 days; and dyspnea, 2.2 ±0.5 days.
Test Method
A brief medical history, patients height and weight, and room temperature were obtained prior to the commencement of the study. Pulse, blood pressure, respiratory rate, physical examination of the lungs, and spirometry were performed with the patient sitting upright before and 30 minutes after completion of aerosol treatments. A minimum of three spirometric curves of at least 4-s duration was obtained using a dry rolling seal spirometer (Ohio Medical Products, Houston, TX). The spirometric curves were required to have a smooth continuous contour and to be reproducible such that the FVC did not vary by 5 percent or 100 ml, whichever was greater. The FVC, FEV,, and FEF25-75 were calculated from the spirogram with the largest FVC. The spirometer was calibrated daily. Predicted normal values for spirometric parameters were determined using the data of Crapo et al.