Heated Humidified High-Flow Nasal Cannula: Impact on Neonatal Outcomes.

The use of heated humidified high-flow nasal cannula (HFNC) as an alternative to CPAP in neonates has increased in recent years and seems to have gone viral.1 HFNC as a method of respiratory support to aid in extubation has increased in popularity following randomized controlled trials showing no difference in extubation failure rates or other outcomes between HFNC and CPAP in neonates at 26 weeks’ gestation.2-4 Campbell et al,5 however, have shown CPAP to be superior. HFNC is now used for reasons other than as a method to aid in extubation and as an alternative to CPAP. This is because of the impression that HFNC is easier to use in terms of application and maintenance, there is less nasal trauma, and infant tolerance is good.1,6,7 However, unpredictable distending pressures during HFNC raise justifiable concerns. Studies, although inconsistent and highly variable, have demonstrated pressures as high as 6 cm H2O with a flow as low as 2 L/min in neonates.8,9 A randomized controlled trial revealed that weaning neonates from CPAP to HFNC was associated with an increased oxygen exposure and duration of respiratory support.10 Other cohort studies similarly reported an increased duration of respiratory support and chronic lung disease in the post-HFNC era and hypothesized that variable distending pressures may promote progressive atelectasis,11 whereas a more recent publication also showed a higher risk of death or chronic lung disease/bronchopulmonary dysplasia, increased respiratory morbidities, delayed oral feeding, and increased length of stay.12 This increased respiratory support was also confirmed in a Cochrane review, but there was no increase in chronic lung disease.13 In this issue of RESPIRATORY CARE, a retrospective study by Hoffman et al14 of 163 neonates at 33 weeks’ gestation compared 2 eras of respiratory management, the first from April 2011 to April 2012 (pre-HFNC era) and the second from August 2012 to August 2013 (post-HFNC era). The results led the investigators to reassess their use of HFNC. With the introduction of HFNC in 2012, 68% of neonates received HFNC, and of those who received HFNC, 95% also received CPAP. The use of HFNC often followed CPAP, suggesting a preference for HFNC during the weaning period rather than an alternative method for primary respiratory support.