Cannula With Long and Narrow Tubing ("Ram") vs Short Binasal Prongs for Noninvasive Ventilation in Preterm Infants: Noninferiority Randomized Clinical Trial

Background: Ram cannula use has gained increasing popularity in applying noninvasive respiratory support for newborn infants thanks to ease of use, perceived patient comfort and reduced nasal trauma. However, there is concern that this long thin interface delivers reduced and suboptimal support.

Methods: In this dual center, randomized, controlled, noninferiority trial, we assigned 166 preterm infants (gestational age [GA] 240 to 336) who needed noninvasive ventilation to nasal intermittent positive ventilation (NIPPV) with either Ram cannula or short binasal prongs/mask (SPM) interface. The primary outcome was the need for intubation within 72 hours after NIPPV treatment initiation. The chosen margin of noninferiority was 15 percentage difference.

Results: Infants characteristics and clinical condition (including FiO2, pCO2, pH) were comparable at recruitment in the Ram (n=83) and the SPM (n=83) groups: mean (SD) GA- 29.3 (2.2) weeks vs. 29.2 (2.5) weeks, birth weight- 1237 (414) g vs. 1254 (448) g; respectively. Intubation within 72 hours occurred in 12 infants (14.5%) in the Ram cannula group and in 15 infants (18.1%) in the SPM group (risk difference -3.6%; 95% confidence-interval, -14.8 to 7.6 [within the noninferiority margin], chi-square p value=0.53). Moderate to severe nasal trauma was significantly less common in the Ram cannula group compared to the SPM group (5% vs. 17%, p=0.01). There was no difference in other adverse events or in the neonatal course.

Conclusion: In this study, Ram cannula was noninferior to short binasal prongs or mask in providing NIPPV for preterm infants, while causing significantly less nasal trauma.