Published: 08 April 2022
A commonly used means of delivering additional oxygen to children in intensive care is not as effective as many clinicians assume, according to new NIHR-funded research.
The FIRST-ABC trial, published in the Journal of the American Medical Association, was led by experts at Imperial College London and sponsored by Great Ormond Street Hospital for Children (GOSH).
It was the first to compare the types of breathing support given to children when they come off mechanical ventilation, to help them transition to breathing unaided.
The study compared High-Flow Nasal Cannula therapy (HFNC) – where oxygen is delivered through tubes into the nostrils – with Continuous Positive Airwave Pressure (CPAP) – for which patients wear an oxygen mask. HFNC has become increasingly popular in paediatric intensive care units, as it is seen as more comfortable for children to tolerate.
However, when the two methods were compared, the researchers found that children on HFNC needed breathing support for up to 18 hours longer than those using CPAP.
Dr Padmanabhan Ramnarayan, a Reader in Paediatric Critical Care who also works as a consultant in paediatric intensive care at Imperial College Healthcare NHS Trust, led the trial. He said: “We know that HFNC can’t deliver the same levels of breathing support as CPAP, but it’s been assumed that the reduced effectiveness is a price worth paying for the additional comfort it provides. Our results show that may not be the case.”
Researchers recruited 600 children, ranging from newborn to age 15, in 22 paediatric intensive care units across the UK. Half of the children were randomised to move to HFNC following ventilation and the other half to CPAP.
The team set a maximum threshold of no more than 16 hours of additional time on breathing support with HFNC, given the extra comfort it provides. This limit was based on an earlier pilot study and focus groups with parents.
The trial showed that children on average spent 43 hours on breathing support with CPAP, and 51 with HFNC, eight hours longer. However, for some, the additional time was as much as 18 hours, breaching the trial’s upper limit.
Only 10 percent of children who started on CPAP following ventilation failed to tolerate it, and were moved to HFNC as a result. The team also found that these findings were consistent irrespective of the age of the child and the conditions for which they were hospitalised.
Dr Ramnarayan added: “Most paediatricians have tended to prefer HFNC, but these results are likely to make them more cautious.
“While the choice of breathing support is specific to each patient, my own preference now is to start with CPAP, and if children struggle to tolerate it, only then to use HFNC as the next option.”
The team is currently analysing the data from a second trial, following the same format, which compares CPAP and HFNC when used as the first breathing support provided in children who have not yet been put onto a ventilator. The findings will be published later this year.
FIRST-ABC was funded by NIHR’s Health Technology Assessment (HTA)Programme.