Impact of Duration of Nasal High Flow Therapy on Respiratory Outcomes in Very Preterm Infants: A Propensity Score...

Nasal high flow therapy (nHFT) is being used earlier and for longer than in the past as an alternative to nasal Continuous Positive Airway Pressure (nCPAP) for preterm neonates. The aim of the present study was to evaluate the effect of the proportion of nHFT on respiratory outcomes.

This was a single-centre retrospective study of preterm infants born <32 weeks' gestational age from 2016 to 2025. Propensity score weighting analysis was used to explore the effect of the duration of nHFT expressed as a percentage of the total duration of nHFT or nCPAP (nHFT%). The primary outcome was the total duration of respiratory support; secondary outcomes were the development of bronchopulmonary dysplasia (BPD) and the length of hospitalisation.

Three hundred and forty two infants were included. Infants received nHFT for a median (Q1, Q3) of 70 (46, 85) % of the duration of nHFT or nCPAP (nHFT%). After adjusting for residual confounders, the weighted nHFT% presented a significant positive association with the total duration of respiratory support (β = 0.007, p < 0.001), oxygen requirement (β = 0.006, p = 0.027), and the length of hospitalisation (β = 0.002, p = 0.007). The risk for BPD tended to increase with increasing nHFT% (OR = 1.01, p = 0.287).

The prolonged use of nHFT as an alternative to nCPAP was associated with a longer duration of respiratory support and hospitalisation, but not with a higher risk for BPD.