Helium-oxygen therapy for infants with bronchiolitis: a randomized controlled trial.

OBJECTIVE To compare nebulized racemic epinephrine delivered by 70% helium and 30% oxygen or 100% oxygen followed by helium-oxygen inhalation therapy via high-flow nasal cannula (HFNC) vs oxygen inhalation via HFNC in the treatment of bronchiolitis. DESIGN Prospective, randomized, controlled, single-blind trial. SETTING This study was conducted from October 1, 2004, through May 31, 2008, in the emergency department of an urban, tertiary care children's hospital. Patients Infants aged 2 to 12 months with a Modified Wood's Clinical Asthma Score (M-WCAS) of 3 or higher. INTERVENTIONS Patients initially received nebulized albuterol treatment driven by 100% oxygen. Patients were randomized to the helium-oxygen or oxygen group and received nebulized racemic epinephrine via a face mask. After nebulization, humidified helium-oxygen or oxygen was delivered by HFNC. After 60 minutes of inhalation therapy, patients with an M-WCAS of 2 or higher received a second delivery of nebulized racemic epinephrine followed by helium-oxygen or oxygen delivered by HFNC. Main Outcome Measure Degree of improvement of M-WCAS for 240 minutes or until emergency department discharge. RESULTS Of 69 infants enrolled, 34 were randomized to the helium-oxygen group and 35 to the oxygen group. The mean change in M-WCAS from baseline to 240 minutes or emergency department discharge was 1.84 for the helium-oxygen group compared with 0.31 for the oxygen group (P < .001). The mean M-WCAS was significantly improved for the helium-oxygen group compared with the oxygen group at 60 minutes (P = .005), 120 minutes (P < .001), 180 minutes (P < .001), and 240 minutes (P < .001). CONCLUSION Nebulized racemic epinephrine delivered by helium-oxygen followed by helium-oxygen inhalation therapy delivered by HFNC was associated with a greater degree of clinical improvement compared with that delivered by oxygen among infants with bronchiolitis. Trial Registration clinicaltrials.gov Identifier: NCT00116584.