• Neonatology
• Resuscitation
• Respiratory

Like sneezing baby pandas, ice bucket challenges and Susan Boyle, nasal high-flow (nHF) use in neonatology is ‘going viral’.

One can only hope that the Archives servers have sufficient capacity to cope with the increased traffic that the article on nHF use in the delivery room by Reynolds and colleagues1 is sure to generate.

Humidified, heated, nHF devices have been commercially available for more than a decade. Over that time, the use of nHF to treat preterm infants around the world has dramatically increased as it has been perceived as an easier-to-use, gentler, alternative ‘non-invasive’ support to nasal continuous positive airway pressure (CPAP). For example, in 2013 in the Australian and New Zealand Neonatal Network, 24% of all tertiary neonatal intensive care unit (NICU) registrants received nHF, a marked increase from about 8% in 2009.2 In this cohort, nHF use was predominantly in very preterm infants born <30 weeks gestation: about 60% of this group received nHF during their hospital admission. Anecdotally, some tertiary NICUs around the world have replaced CPAP with HF as their preferred mode of respiratory support for preterm infants.

As the popularity of nHF increases, there is accumulating evidence from clinical trials that it may be safely used to provide respiratory support for preterm infants in some clinical scenarios. Currently, in the neonatal population, most evidence is available for nHF as an alternative to CPAP for postextubation support for preterm infants in the NICU,3–5 although caution is recommended in extremely preterm infants where little data are available. While treatment failure rates after extubation favour CPAP over HF, without reaching statistical significance, rates of reintubation are no different due to several studies allowing ‘rescue’ CPAP when nHF failed.

The number of newborn infants randomised to nHF as ‘first line’ or early respiratory support in the NICU remains small, and there is substantial uncertainty about its usefulness in this setting, particularly for the most immature infants. Should nHF be shown to be efficacious and safe as primary respiratory support for newborn infants, it is a promising therapy for non-tertiary settings and potentially low-income and middle-income countries due to its ease of use for nursing staff.

Reynolds and colleagues from St Peter's Hospital, Surrey, UK, present the results of a case series of 28 very preterm infants born <30 weeks gestation in whom the intent was to use nHF for delivery room stabilisation and transfer to the NICU. This is the first study to report the use of nHF for this clinical indication, and they are to be commended for their efforts, particularly for recruiting such an immature cohort.

About 90% of infants were successfully stabilised and transferred to the NICU on nHF. Three of the four infants born at 23 or 24 weeks required intubation and ventilation in the delivery room. About half the infants that remained on nHF required surfactant treatment. The authors conclude that it is feasible to stabilise very preterm infants born <30 weeks gestation with nHF in the delivery room and transfer them to the NICU where nHF treatment may continue.

Stabilisation of preterm infants in the delivery room is a unique clinical scenario—even if nHF is a useful early respiratory support modality in the NICU, it may not be sufficient to aid transition in the first minutes of life. Current standard practice in the delivery room is to apply CPAP pressures of up to 8 cm of water in order to open the airway and establish and maintain functional residual capacity; pressures this high may not be achieved with nHF at gas flows up to 8 L/min, the current recommended maximum. The use of CPAP in the delivery room to stabilise preterm infants has been well studied, and practice should not change without evidence of benefit, or at least non-inferiority, of nHF from well-powered randomised trials.

While the study by Reynolds is promising, it has limitations that are appropriately acknowledged by the authors, and the results should be considered hypothesis-generating. It is a pilot study conducted in a single centre with 8 years experience using nHF in premature infants. There is the potential for bias favouring nHF because staff were familiar with its use and because treatment failure criteria were not objective. Limited information is available on why nHF treatment failed in some infants: it would be nice to know, for example, whether nHF failure was due to apnoea, increased work of breathing or high supplemental oxygen requirement.

The generalisability of the results is limited to neonatal units with experience using nHF, and by the fact that only 38% of eligible infants born during the study period were able to be included in the study. A prototype, mobile version of the Vapotherm Precision Flow nHF system was used, and while there is currently no evidence that any heated, humidified nHF system is superior to another, other nHF systems will also need to be tested.

It is interesting that the results of this study are available while other studies of nHF as early respiratory support in the neonatal unit (after stabilisation in the delivery room with CPAP if required) are ongoing. If these studies show that nHF is better or worse than CPAP, will there still be the desire to undertake a randomised trial of nHF in the delivery room?

While nHF has several potential advantages over CPAP, and undoubtedly has an important place in the care of preterm infants, the neonatal nHF ‘pandemic’ must be contained pending further evidence from randomised clinical trials.

Until then, neonatologists must control their FOMO.

Google it, peeps.