High-flow oxygen helpful in hospitalized infants with bronchiolitis

Reference

Franklin D, Babl FE, Schlapbach LJ, et al. A randomized trial of high-flow oxygen therapy in infants with bronchiolitis. N Engl J Med 2018;378(12):1121-1131.

Synopsis

This study identified infants younger than 12 months with clinically diagnosed bronchiolitis and hypoxemia with supplemental oxygen required to keep their oxygen saturation at 92% or higher. Children with serious comorbid cardiopulmonary disease and those who required initial intensive care unit (ICU) admission were excluded. Infants were randomized with concealed allocation to high-flow oxygen (2 liters/kg/minute) or standard-flow oxygen (up to 2 liters/minute). Weaning off oxygen was allowed as long as an oxygen saturation of at least 92% was maintained. An important limitation of the study is that the study, including outcome assessment and the decision to escalate care, was not masked. Of the more than 20,000 infants screened for the study, only 2271 were eligible (most excluded patients either didn't require oxygen or didn't have bronchiolitis), 1638 underwent randomization, and 1472 were included in the analysis. The groups were balanced at the start of the study, with a mean age of 6 months, 23% of patients having a patient history of wheeze, and slightly more than 50% of patients with bronchiolitis caused by respiratory syncytial virus (RSV). Of the 733 infants originally randomized to receive standard oxygen, 167 crossed over to high-flow oxygen because of clinical deterioration according to study protocol. However, 61% responded and did not require further escalation. The primary outcome was treatment failure requiring an escalation in care, defined as meeting at least 3 of the following 4 criteria: heart rate unchanged or increased, respiratory rate unchanged or increased, oxygen requirement to maintain 92% oxygen saturation required more oxygen than was allowed by the assigned group, or a hospital "early warning system" in the form of a clinical score triggered a review. Treatment failure was less likely in the high-flow group (12% vs 23%; 95% CI -15% to -7% for the difference between groups; number needed to treat = 9 to prevent one treatment failure). The treatment was equally effective regardless of age or whether the infection was caused by RSV. However, there was no difference in length of stay, mortality, or need for ICU admission or intubation. There were no serious treatment-related adverse events, with one pneumothorax in each group.