What CPAP to use in the delivery room? Bench comparison of two methods to provide continuous positive airways pressure in neonates.

Background: Continuous positive airway pressure (CPAP) is a recommended first-line therapy for infants with respiratory distress at birth. Resuscitation devices incorporating CPAP delivery can have significantly different imposed resistances affecting airway pressure stability and work of breathing.

Aim: To compare CPAP performance of two resuscitation devices (Neopuff T-piece resuscitator and rPAP) in a neonatal lung model simulating spontaneous breathing effort at birth.

Methods: The parameters assessed were variation in delivered pressures (∆P), tidal volume (VT), inspiratory effort (model pressure respiratory muscle (PRM)) and work of breathing (WOB). Two data sequences were required with Neopuff and one with rPAP: (1) set PRM with changes in VT and (2) constant VT (preterm 6 mL, term 22 mL) with increased effort. Data were collected at CPAP settings of 5, 7 and 9 cmH₂O using a 1 kg preterm (Compliance: 0.5 mL/cmH₂O) and 3.5 kg term (1.0 mL/cmH₂O) model.

Results: 2298 breaths were analysed (760 rPAP, 795 Neopuff constant VT, 743 Neopuff constant PRM). With CPAP at 9 cmH₂O and set VT the mean ∆P (cmH₂O) rPAP vs Neopuff 1.1 vs 5.6 (preterm) and 1.9 vs 13.4 (term), WOB (mJ) 4.6 vs 6.1 (preterm) and 35.3 vs 44.5 (term), and with set PRM mean VT (ml) decreased to 6.2 vs 5.2 (preterm) and 22.3 vs 17.5 (term) p<0.001. Similar results were found at pressures of 5 and 7 cmH₂O.

Conclusion: rPAP had smaller pressure swings than Neopuff at all CPAP levels and was thus more pressure stable. WOB was higher with Neopuff when VT was held constant. VT reduced with Neopuff when respiratory effort was constant.