The SaOa was measured noninvasively by pulse oximetry when the patients were awake and breathing room air. On disposition from the ER, the SaO measurement was made at least 30 minutes after the final treatment with nebulized albuterol.
The patients in the study were independently assessed and treated by pediatric residents, under the supervision of staff physicians, all of whom were unaware of the results of the clinical score, pulmonary function, or Sa02 measurements. Neither the treatment, duration of ER care, nor hospitalization/discharge decisions were governed by protocol. However, the first-line treatment for acute asthma at this institution consists of one or more inhalations of a 0.5 percent solution of albuterol (0.03 ml/kg, maximum 1 ml/dose) in 3 ml normal saline solution, delivered by nebulizer at an oxygen rate of 6 to 8 L/min. The use of parenteral theophylline or corticosteroids in the present study was at the discretion of the ER physicians. In general, the decision to admit or discharge a patient was made within 2 to 4 h of arrival in the ER.
The parents of children who were discharged home from the ER were contacted by telephone seven days later, and information was obtained regarding the need for additional ER care and/or hospitalization.