Original Contributions
Albuterol nebulized in heliox in the initial ED treatment of pediatric asthma: a blinded, randomized controlled trial

A poster presentation of an abstract of this work was presented at the Pediatric Academic Societies annual meeting, San Francisco, Calif, May 1999, and at the annual meeting of the American Academy of Pediatrics Section of Pediatric Emergency Medicine, Washington, DC, October 1999.
https://doi.org/10.1016/j.ajem.2005.06.007Get rights and content

Abstract

Objective

A prospective blinded, randomized controlled trial was undertaken to compare the initial response of albuterol nebulized in heliox or control in the treatment of moderately severe asthma in children presenting to a pediatric ED.

Methods

Patients were randomized to receive heliox (n = 20) or control (n = 21). The primary outcome was to compare a modified dyspnea index score at 10 and 20 minutes after randomization. Secondary outcomes were to determine if heliox decreased admission rates or endotracheal intubation.

Results

There was no statistically significant difference found at 10 or 20 minutes after randomization with heliox (P = .169 and P = .062, respectively). No statistical difference in admission rate was found, and no patients required endotracheal intubation in either group.

Conclusions

Our results demonstrate that albuterol nebulized with heliox offered no clinical benefit over standard therapy in the initial treatment of moderately severe asthma in the ED.

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

References (24)

  • J.D. Tobias

    Heliox in children with airway obstruction

    Pediatr Emerg Care

    (1997)
  • M. Anderson et al.

    Deposition in asthmatics of particles inhaled in air or helium-oxygen

    Am Rev Respir Dis

    (1993)
  • Cited by (49)

    • Improving Management of Severe Asthma: BiPAP and Beyond

      2018, Clinical Pediatric Emergency Medicine
    • Pediatric Respiratory Emergencies

      2016, Emergency Medicine Clinics of North America
    • Heliox-driven β<inf>2</inf>-agonists nebulization for children and adults with acute asthma: A systematic review with meta-analysis

      2014, Annals of Allergy, Asthma and Immunology
      Citation 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

      2013, Emergency Medicine Clinics of North America
    • Pediatric Status Asthmaticus

      2013, Critical Care Clinics
      Citation Excerpt :

      Unfortunately, the literature regarding the effectiveness of this therapy in children with acute asthma has been mixed.56–59 Randomized controlled studies of helium-oxygen therapy in this population have been contradictory and have not demonstrated efficacy in terms of shortening durations of exacerbation or improving outcomes.56–59 Furthermore, to significantly reduce airways resistance, 60% to 80% helium is needed in the gas mixture.

    • Asthma Diagnosis and Management

      2012, Emergency Medicine Clinics of North America
    View all citing articles on Scopus

    Departmental funds were the sole support for this project.

    View full text