Researchers from multiple institutions compared the time to weaning off oxygen in young children with bronchiolitis who were hospitalized at a single Australian institution when treated with high-flow warm humidified oxygen (HFWHO) or standard low-flow nasal cannula. Children were eligible if they were <24 months old, presented to the emergency department or were admitted to the ward with a clinical diagnosis of bronchiolitis of moderate severity (with severity determined by using an Australian clinical practice guideline), and required supplemental oxygen (defined as having one of the following: abnormal heart rate, abnormal respiratory rate, decreased oxygen saturation of ≤94%, or increased work of breathing). Demographics, medical history, and clinical symptoms were documented at baseline. Child participants were randomized to HFWHO (maximum flow of 1 L/kg/min to a limit of 20 L/min for a maximum FIO2 of 0.6) or standard therapy (cold wall oxygen 100% at low flow to a maximum of 2 L/min). Participants in both treatment arms were started on maximum oxygen therapy for a minimum of 3 hours, at which point weaning was permitted by using a standardized protocol developed for the trial, which incorporated clinical respiratory symptoms, heart rate, respiratory rate, oxygen saturation, and ability to feed.
The primary study outcome was time to weaning off oxygen. Secondary outcomes included the proportion of patients who experienced treatment failure 24 hours after enrollment, with failure defined as critically abnormal observations of the standardized protocol while on maximum therapy (eg, SpO2 <90% or other vital sign deterioration), along with a clinical decision by the treating physician that the current treatment was insufficient to reverse the deterioration. Outcomes were compared among children in the 2 treatment groups.
There were 202 participants enrolled, with 101 in each group. Baseline characteristics were balanced between groups. In intention-to-treat analysis, time to weaning off oxygen did not differ significantly between the HFWHO and standard therapy groups (median times, 20 vs 24 hours, respectively; P = .61). Per-protocol results were similar. However, significantly more standard therapy participants experienced treatment failure at 24 hours than did HFWHO participants.
The researchers conclude that there is no difference in the time to weaning off oxygen between HFWHO and standard therapy for young children with moderate bronchiolitis. However, use of HFWHO may reduce the number of children who experience treatment failure.
Dr. Lesser has disclosed no financial relationship relevant to this commentary. This commentary does not contain a discussion of an unapproved/investigative use of a commercial product/device.
Use of HFWHO to support children with bronchiolitis who are hospitalized outside of the intensive care unit has become increasingly common in tertiary care centers. Most practitioners would probably agree that the goals of respiratory support in bronchiolitis include...