Original ContributionsAlbuterol nebulized in heliox in the initial ED treatment of pediatric asthma: a blinded, randomized controlled trial☆
Introduction
Asthma is a common, potentially life-threatening condition affecting many children in the United States. It accounts for 1.7 million pediatric ED visits annually [1]. Despite current available therapy with use of bronchodilators and corticosteroids, alleviation of obstruction may not occur rapidly enough to prevent ventilatory failure and endotracheal intubation.
Helium is a biologically inert gas that was first isolated from atmospheric air by Ramsay in 1895. The clinical use of helium mixed with oxygen was recognized and investigated in 1935 by Barach [2], [3], [4] who advocated its use in the treatment of obstructive disorders of the trachea, larynx, and bronchi.
Heliox, a mixture of helium and oxygen, has been shown to successfully reverse airway obstruction in patients unresponsive to conventional therapy [5], [6]. Heliox is an inert gas that is one third as dense as air. When used for asthma therapy, it has been shown to improve oxygenation, increase carbon dioxide elimination, increase expiratory flow, decrease work of breathing, and enhance delivery of aerosolized medications to the peripheral alveoli [6], [7], [8], [9], [10], [11], [12]. To date, most heliox studies involve adult or hospitalized patients.
We undertook a blinded, randomized controlled trial to determine if the delivery of continuous nebulized albuterol with heliox led to greater clinical improvement over nebulized albuterol delivered with oxygen.
Section snippets
Methods
The study was performed in the pediatric ED of a tertiary care, urban, university-based children's hospital following CONSORT recommendations [13]. We selected children 3 to 16 years of age who presented to the ED between September 1, 1998, to November 30, 1998, with the principal complaint of asthma exacerbation. Inclusion criteria included a previous history of asthma as defined by at least 3 prior episodes of reversible bronchospasm and a modified dyspnea index of 4 or higher on presentation
Results
Forty-one patients aged 3 to 16 years were approached for enrollment in the study. No patients refused enrollment or needed to be withdrawn before completion of the study (Fig. 1). Twenty patients were randomized to receive heliox, and 21 patients received 30% oxygen. There was no clinical or statistical differences in baseline characteristics between the study groups (Table 2). Blinding was maintained. No child spoke to the study investigator assigning the modified dyspnea index scores, and
Discussion
This is the first prospective randomized blinded study that we are aware of evaluating the early use of continuous albuterol nebulized with heliox in the pediatric ED. Our results demonstrate that heliox offered no clinical benefit over standard therapy in the initial treatment of moderately severe asthma in the ED.
Literature to date strongly supports the use of heliox for treatment of obstructive conditions of the upper airway [2], [3], [4], [5], [6]. It has also been found to be beneficial in
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2014, Annals of Allergy, Asthma and ImmunologyCitation Excerpt :Most studies enrolled children and adults with acute severe asthma. Four studies used a helium–oxygen mixture of 80:20,18,19,23,26 6 used a 70:30 mixture,17,20–22,24,25 and 1 used a 79:21 mixture.21 In 5 studies, β2-agonists were administered in a continuous form.18,22,24,25
Childhood asthma. A guide for pediatric emergency medicine providers
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Asthma Diagnosis and Management
2012, Emergency Medicine Clinics of North America
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Departmental funds were the sole support for this project.