Oxygen saturation targets in infants with bronchiolitis could be lowered, the first randomised trial of its kind shows, but Australian experts say a nagging question still remains.
The double-blind randomized equivalence Bronchiolitis of Infancy Discharge Study (BIDS) involved 615 infants aged between 6 weeks and 12 months who were admitted with bronchiolitis to one of eight paediatric hospitals in the UK.
The infants were assigned to monitoring with a standard oximeters or a modified oximeter that had a skewed algorithm displaying an Sp02 reading of 94% when the measured value was 90%. Supplemental oxygen was given to all infants with an Sp02 reading of lower than 94% on their oximeter.
The study’s primary outcome of median time to resolution of cough was 15 days for both groups, the researchers reported in the Lancet.
Fewer infants in the modified oximeter group needed supplemental oxygen (56% vs 73%). Those that did required it for a significantly shorter duration (5·7 h vs 27·6 h) compared to the standard group.
The infants in the modified oximeter group were also fit for discharge significantly earlier, returned to adequate feeding sooner, and had fewer readmissions to hospital within 28 days compared with those in the standard group.
Overall 35 serious adverse events occurred in 32 infants in the standard care group and 25 serious adverse events in 24 infants in the modified care group.
“Management of infants with bronchiolitis to an oxygen saturation target of 90% or higher is as safe and clinically effective as one of 94% or higher,” the authors concluded.
Writing in an accompanying editorial Claire Wainwright and Nitin Kapur from the Lady Cilento Children’s Hospital in Brisbane noted that the primary outcome chosen by the authors was unusual for clinical trials of bronchiolitis.
“The association between duration of cough and degree of hypoxaemia is not established, and it is interesting to speculate whether the results of cough duration would have been any different if an even lower saturation cut-off was chosen,” they wrote.
Although the study provided evidence that reduced oxygen saturation targets in bronchiolitis were safe in the short term, the longer term neurocognitive and behavioural outcomes were unknown, they said.
“We urge consideration of long-term neurobehavioural follow-up of randomised trials such as BIDS to shed light on the nagging question that remains”, she concluded.
In practice target oxygen saturations in Australia varied between institutions, Dr Wainwright told the limbic.
“The Royal Children’s Hospital in Melbourne say there is no oxygen requirement when saturations are >93% and that probably reflected the majority of hospital practices,” she said.