Intravenous albuterol effective for acute severe asthma

ABSTRACT

BACKGROUND: Bolus intravenous (IV) albuterol (salbutamol) improved outcomes in pediatric patients with severe asthma exacerbations in 1 earlier small study. Previous studies demonstrated that the addition of nebulized ipratropium bromide to initial emergency department therapy improves pulmonary function, but it is unclear whether combining the therapies results in earlier hospital discharge. This study compared these 2 approaches to determine their relative benefit in children with acute severe asthma.

POPULATION STUDIED: The researchers studied 55 children (aged 1–14 years) presenting with severe acute asthma to the emergency department of a ter-tiary children’s hospital in Sydney, Australia. Children were classified as having severe asthma if they had all 4 features of respiratory distress (wheezing, sternal retraction, accessory muscle use, and dyspnea) or had any of the absolute criteria (cyanosis, pulsus paradoxus, altered consciousness, or a silent chest auscultation). Baseline demographics and clinical characteristics were similar. Children who were excluded included those with life-threatening asthma, age younger than 12 months, presence of heart disease, family history of Wolff-Parkinson-White or past supraventricular tachycardia, other respiratory disease, or pneumonia, and those who had received inhaled ipratropium bromide that day.

STUDY DESIGN AND VALIDITY: This was a randomized, double-blind, double-dummy trial. The enrolling physician, treating physician, and assessor of outcome were all blinded. All children received 1 dose of nebulized albuterol 2.5 or 5 mg, then were assessed for asthma severity. Children meeting inclusion criteria received oxygen as needed, 1 mg/kg IV bolus methylprednisolone, and nebulized albuterol every 20 minutes for the first hour. The frequency of nebulized albuterol was then decreased based on clinical improvement. Patients were then randomized to receive IV albuterol (15 μg/kg); IV saline and inhaled ipratropium bromide (250 mg) every 20 minutes; or IV albuterol (15 μg/kg) and inhaled ipratropium bromide (250 μg) every 20 minutes. Asthma severity was assessed at 1 and 2 hours into the study using the clinical assessment scale and pulmonary index score. All 55 children completed the study.

OUTCOMES MEASURED: The primary outcomes for this study were mean recovery time (time from randomization to when patients no longer needed nebulized albuterol of a given frequency) and mean discharge time from the hospital. Secondary outcomes included clinical signs of moderate to severe asthma 2 hours after randomization and incidence of medication-related side effects.

RESULTS: Children treated with IV albuterol showed a significant benefit over those treated with inhaled ipratropium in recovery at 90, 120, and 180 minutes (P = .007, .01, and .004, respectively). Children in the IV albuterol group were ready for discharge 28.0 hours earlier than those in the ipratropium group (48.3 vs 76.3 hours; P = .005). The combination of IV albuterol and ipratropium showed a significant benefit over ipratropium alone in recovery time at 90 and 120 minutes (P = .02 and .008, respectively). However, no significant difference was evident between the combination and ipratropium alone in time to discharge (57.6 vs 76.3 hours, respectively; P = .2). The combination demonstrated no significant benefit over IV albuterol for any outcome. No significant adverse effects were documented in any of the patients, including tachycardia of more than 200 beats per minute for at least 5 minutes.